The invention relates to inhibitors of 11β-hydroxysteroid dehydrogenase. The inhibitors include, for example, aryl sulfonyl piperidines and are useful for the treatment of diseases such as type II diabetes mellitus and metabolic syndrome.
All documents cited or relied upon below are expressly incorporated herein by reference.
Diabetes mellitus is a serious illness that affects an increasing number of people across the world. Its incidence is escalating parallel to the upward trend of obesity in many countries. The serious consequences of diabetes include increased risk of stroke, heart disease, kidney damage, blindness, and amputation.
Diabetes is characterized by decreased insulin secretion and/or an impaired ability of peripheral tissues to respond to insulin, resulting in increased plasma glucose levels. There are two forms of diabetes: insulin-dependent and non-insulin-dependent, with the great majority of diabetics suffering from the non-insulin-dependent form of the disease, known as type 2 diabetes or non-insulin-dependent diabetes mellitus (NIDDM). Because of the serious consequences, there is an urgent need to control diabetes.
Treatment of NIDDM generally starts with weight loss, a healthy diet and an exercise program. These factors are especially important in addressing the increased cardiovascular risks associated with diabetes, but they are generally ineffective in controlling the disease itself. There are a number of drug treatments available, including insulin, metformin, sulfonylureas, acarbose, and thiazolidinediones. However, each of these treatments has disadvantages, and there is an ongoing need for new drugs to treat diabetes.
Metformin is an effective agent that reduces fasting plasma glucose levels and enhances the insulin sensitivity of peripheral tissue. Metformin has a number of effects in vivo, including an increase in the synthesis of glycogen, the polymeric form in which glucose is stored [R. A. De Fronzo Drugs 1999, 58 Suppl. 1, 29]. Metformin also has beneficial effects on lipid profile, with favorable results on cardiovascular health—treatment with metformin leads to reductions in the levels of LDL cholesterol and triglycerides [S. E. Inzucchi JAMA 2002, 287, 360]. However, over a period of years, metformin loses its effectiveness [R. C. Turner et al. JAMA 1999, 281, 2005] and there is consequently a need for new treatments for diabetes.
Thiazolidinediones are activators of the nuclear receptor peroxisome-proliferator activated receptor-gamma. They are effective in reducing blood glucose levels, and their efficacy has been attributed primarily to decreasing insulin resistance in skeletal muscle [M. Tadayyon and S. A. Smith Expert Opin. Investig. Drugs 2003, 12, 307]. One disadvantage associated with the use of thiazolidinediones is weight gain.
Sulfonylureas bind to the sulfonylurea receptor on pancreatic beta cells, stimulate insulin secretion, and consequently reduce blood glucose levels. Weight gain is also associated with the use of sulfonylureas [S. E. Inzucchi JAMA 2002, 287, 360] and, like metformin, they lose efficacy over time [R. C. Turner et al. JAMA 1999, 281, 2005]. A further problem often encountered in patients treated with sulfonylureas is hypoglycemia [M. Salas J. J. and Caro Adv. Drug React. Tox. Rev. 2002, 21, 205-217].
Acarbose is an inhibitor of the enzyme alpha-glucosidase, which breaks down disaccharides and complex carbohydrates in the intestine. It has lower efficacy than metformin or the sulfonylureas, and it causes intestinal discomfort and diarrhea which often lead to the discontinuation of its use [S. E. Inzucchi JAMA 2002, 287, 360]
Because none of these treatments is effective over the long term without serious side effects, there is a need for new drugs for the treatment of type 2 diabetes.
The metabolic syndrome is a condition where patients exhibit more than two of the following symptoms: obesity, hypertriglyceridemia, low levels of HDL-cholesterol, high blood pressure, and elevated fasting glucose levels. This syndrome is often a precursor of type 2 diabetes, and has a high estimated prevalence in the United States of 24% (E. S. Ford et al. JAMA 2002, 287, 356). A therapeutic agent that ameliorates the metabolic syndrome would be useful in potentially slowing or stopping the progression to type 2 diabetes.
In the liver, glucose is produced by two different processes: gluconeogenesis, where new glucose is generated in a series of enzymatic reactions from pyruvate, and glycolysis, where glucose is generated by the breakdown of the polymer glycogen.
Two of the key enzymes in the process of gluconeogenesis are phosphoenolpyruvate carboxykinase (PEPCK) which catalyzes the conversion of oxalacetate to phosphoenolpyruvate, and glucose-6-phosphatase (G6Pase) which catalyzes the hydrolysis of glucose-6-phosphate to give free glucose. The conversion of oxalacetate to phosphoenolpyruvate, catalyzed by PEPCK, is the rate-limiting step in gluconeogenesis. On fasting, both PEPCK and G6Pase are upregulated, allowing the rate of gluconeogenesis to increase. The levels of these enzymes are controlled in part by the corticosteroid hormones (cortisol in human and corticosterone in mouse). When the corticosteroid binds to the corticosteroid receptor, a signaling cascade is triggered which results in the upregulation of these enzymes.
The corticosteroid hormones are found in the body along with their oxidized 11-dehydro counterparts (cortisone and 11-dehydrocorticosterone in human and mouse, respectively), which do not have activity at the glucocorticoid receptor. The actions of the hormone depend on the local concentration in the tissue where the corticosteroid receptors are expressed. This local concentration can differ from the circulating levels of the hormone in plasma, because of the actions of redox enzymes in the tissues. The enzymes that modify the oxidation state of the hormones are 11beta-hydroxysteroid dehydrogenases forms I and II. Form I (11β-HSD1) is responsible for the reduction of cortisone to cortisol in vivo, while form 11 (11β-HSD2) is responsible for the oxidation of cortisol to cortisone. The enzymes have low homology and are expressed in different tissues. 11β-HSD1 is highly expressed in a number of tissues including liver, adipose tissue, and brain, while 11β-HSD2 is highly expressed in mineralocorticoid target tissues, such as kidney and colon. 11β-HSD2 prevents the binding of cortisol to the mineralocorticoid receptor, and defects in this enzyme have been found to be associated with the syndrome of apparent mineralocorticoid excess (AME).
Since the binding of the 11β-hydroxysteroids to the corticosteroid receptor leads to upregulation of PEPCK and therefore to increased blood glucose levels, inhibition of 11β-HSD1 is a promising approach for the treatment of diabetes. In addition to the biochemical discussion above, there is evidence from transgenic mice, and also from small clinical studies in humans, that confirm the therapeutic potential of the inhibition of 11β-HSD1.
Experiments with transgenic mice indicate that modulation of the activity of 11β-HSD1 could have beneficial therapeutic effects in diabetes and in the metabolic syndrome. For example, when the 11β-HSD1 gene is knocked out in mice, fasting does not lead to the normal increase in levels of G6Pase and PEPCK, and the animals are not susceptible to stress- or obesity-related hyperglycemia. Moreover, knockout animals which are rendered obese on a high-fat diet have significantly lower fasting glucose levels than weight-matched controls (Y. Kotolevtsev et al. Proc. Natl. Acad Sci. USA 1997, 94, 14924). 11β-HSD1 knockout mice have also been found to have improved lipid profile, insulin sensitivity, and glucose tolerance (N. M. Morton et al. J. Biol. Chem. 2001, 276, 41293). The effect of overexpressing the 11β-HSD1 gene in mice has also been studied. These transgenic mice displayed increased 11β-HSD1 activity in adipose tissue, and they also exhibit visceral obesity which is associated with the metabolic syndrome. Levels of the corticosterone were increased in adipose tissue, but not in serum, and the mice had increased levels of obesity, especially when on a high-fat diet. Mice fed on low-fat diets were hyperglycemic and hyperinsulinemic, and also showed glucose intolerance and insulin resistance (H. Masuzaki et al. Science, 2001, 294, 2166).
The effects of the non-selective 11β-hydroxysteroid dehydrogenase inhibitor carbenoxolone have been studied in a number of small trials in humans. In one study, carbenoxolone was found to lead to an increase in whole body insulin sensitivity, and this increase was attributed to a decrease in hepatic glucose production (B. R. Walker et al. J. Clin. Endocrinol. Metab. 1995, 80, 3155). In another study, decreased glucose production and glycogenolysis in response to glucagon challenge were observed in diabetic but not healthy subjects (R. C. Andrews et al. J. Clin. Enocrinol. Metab. 2003, 88, 285). Finally, carbenoxolone was found to improve cognitive function in healthy elderly men and also in type 2 diabetics (T. C. Sandeep et al. Proc. Natl. Acad. Sci USA 2004, 101, 6734).
A number of non-specific inhibitors of 11β-HSD1 and 11β-HSD2 have been identified, including glycyrrhetinic acid, abietic acid, and carbenoxolone. In addition, a number of selective inhibitors of 11β-HSD1 have been found, including chenodeoxycholic acid, flavanone and 2′-hydroxyflavanone (S. Diederich et al. Eur. J. Endocrinol. 2000, 142, 200 and R. A. S. Schweizer et al. Mol. Cell. Endocrinol. 2003, 212, 41).
WO 2004089470, WO 2004089416 and WO 2004089415 (Novo Nordisk A/S) disclose compounds with a number of different structural types as inhibitors of 11bHSD1 useful for the treatment of metabolic syndrome and related diseases and disorders.
WO 0190090, WO 0190091, WO 0190092, WO 0190093, WO 03043999 (Biovitrum AB) disclose compounds as inhibitors of 11β-HSD1. These compounds are different in structure to the compounds of the current invention. WO 2004112781 and WO 2004112782 disclose the method of use of some of these compounds for the promotion of wound healing.
WO 0190094, WO 03044000, WO 03044009, and WO 2004103980 (Biovitrum AB) disclose compounds as inhibitors of 11β-HSD1. These compounds are different in structure to the compounds of the current invention. WO 2004112785 discloses the method of use of some of these compounds for the promotion of wound healing.
WO 03065983, WO 03075660, WO 03104208, WO 03104207, US2004013301 1, WO 2004058741, and WO 2004106294 (Merck & Co., Inc.) disclose compounds as inhibitors of 11β-HSD1. These compounds are different in structure to the compounds of the current invention. US2004122033 discloses the combination of an appetite suppressant with inhibitors of 11β-HSD1 for the treatment of obesity, and obesity-related disorders.
WO 2004065351 (Novartis); WO 2004056744 and WO 2004056745 (Janssen Pharmaceutica N. V.); and WO 2004089367 and WO 2004089380 (Novo Nordisk A/S) discloses compounds as inhibitors of 11β-HSD1. These compounds are different in structure to the compounds of the current invention.
WO 2004089415 (Novo Nordisk A/S) discloses the use of an inhibitor of 11β-HSD1 in combination with an agonist of the glucocorticoid receptor for the treatment of diseases including cancer and diseases involving inflammation. Several different classes of 11β-HSD1 inhibitors are disclosed including amino-ketones, benzimidazoles, carboxamides, 2,3-dihydrobenzofuran-7-carboxamides, indoles, methylenedioxyphenyl-carboxamides, oxazole-4-carboxamides, oxazole-5-carboxamides pyrazolo[1,5-a]pyrimidines, pyrazole-4-carboxamides, thiazole-4-carboxamides, thiazole-5-carboxamides, and 1,2,4-triazoles. WO 2004089416 (Novo Nordisk A/S) discloses the use of an inhibitor of 11β-HSD1 in combination with an antihypertensive agent for the treatment of diseases including insulin resistance, dyslipidemia and obesity. WO 2004089470 (Novo Nordisk A/S) discloses substituted amides as inhibitors of 11β-HSD1.
WO 2004089471 (Novo Nordisk A/S) discloses pyrazolo[1,5-a]pyrimidines as inhibitors of 11β-HSD1; WO 2004089896 (Novo Nordisk A/S) discloses compounds as inhibitors of 11β-HSD1; WO 2004037251A1 (Sterix Limited) discloses sulfonamides as inhibitors of 11β-HSD1; WO 2004027047A2 (Hartmut Hanauske-Abel) discloses compounds as inhibitors of 11β-HSD1; and WO 2004011410, WO 2004033427, and WO 2004041264 (AstraZeneca UK Limited) disclose compounds as inhibitors of 11β-HSD1. These compounds are different in structure to the compounds of the current invention.
WO 02076435A2 (The University of Edinburgh) claims the use of an agent which lowers levels of 11β-HSD1 in the manufacture of a composition for the promotion of an atheroprotective lipid profile. Agents mentioned as inhibitors of 11β-HSD1 include carbenoxolone, 11-oxoprogesterone, 3α,17,21-trihydroxy-5β-pregnan-3-one, 21-hydroxy-pregn-4-ene-3,11,20-trione, androst-4-ene-3,11,20-trione and 3β-hydroxyandrost-5-en-17-one. None of these compounds is similar in structure to the compounds of the current invention.
WO 03059267 (Rhode Island Hospital) claims a method for treating a glucocorticoid-associated state by the administration of a 11β-HSD1 inhibitor such as 11-ketotestosterone, 11-keto-androsterone, 11-keto-pregnenolone, 11-keto-dehydro-epiandrostenedione, 3α,5α-reduced-11-ketoprogesterone, 3α,5α-reduced-11-ketotestosterone, 3α,5α-reduced-11-keto-androstenedione, or 3α,5α-tetrahydro-11β-dehydro-corticosterone. None of these compounds is similar in structure to the compounds of the current invention.
WO 9610022 (Zeneca Limited) discloses 1-[[1-(2-naphthalenylsulfonyl)-3-piperidinyl]carbonyl]-4-(4-pyridinyl)-piperazine as an antithrombotic or anticoagulant agent.
WO 2004018428 (Pharmacia & Upjohn) discloses 5-cyano-2-[[[4-[[3-[(diethylamino)carbonyl]-1-piperidinyl]sulfonyl]-5-methyl-2-thienyl]carbonyl]amino]-benzoic acid as an antibacterial agent
WO 2004018414 (Pharmacia & Upjohn) discloses 5-cyano-2-[[3-[[3-[(diethylamino)carbonyl]-1-piperidinyl]sulfonyl]benzoyl]amino]-benzoic acid and 5-cyano-2-[[4-[[3-[(diethylamino)carbonyl]-1-piperidinyl]sulfonyl]benzoyl]amino]-benzoic acid as antibacterial agents
WO 2002020015 (Merck & Co., Inc.) discloses N-[(1R)-1-(4-cyano-3-fluorophenyl)-1-(1-methyl-1H-imidazol-5-yl)ethyl]-1-[(3-methoxyphenyl)sulfonyl]-3-piperidinecarboxamide and N-[(1R)-1-(4-cyano-3-fluorophenyl)-1-(1-methyl-1H-imidazol-5-yl)ethyl]-1-[(3-hydroxyphenyl)sulfonyl]-3-piperidinecarboxamide as intermediates in the preparation of macrocyclic inhibitors of prenyl-protein transferase.
US 2004029883 (Bayer, A. G., Germany) discloses compounds as inhibitors of inflammatory, autoimmune and immune diseases. These compounds are different in structure to the compounds of the current invention.
GB 2351733 and C. Zhou et al. Bioorg. Med. Chem. Lett. 2001, 11, 415 disclose (βS)—N-[[1-[(4-fluorophenyl)sulfonyl]-3-piperidinyl]carbonyl]-β-methyl-D-tryptophyl-L-Lysine, 1,1-dimethylethyl ester, monoacetate, (βS)—N-[[1-[(3,4-dimethoxyphenyl)sulfonyl]-3-piperidinyl]carbonyl]-β-methyl-D-tryptophyl-L-Lysine, 1,1-dimethylethyl ester, and (βS)-β-methyl-N-[[1-(2-thienylsulfonyl)-3-piperidinyl]carbonyl]-D-tryptophyl-L-Lysine, 1,1-dimethylethyl ester as somatostatin receptor 2 agonists for the treatment and prevention of diabetes, cancer, acromegaly, depression, chronic atrophic gastritis, Crohn's disease, ulcerative colitis, retinopathy, arthritis, pain both visceral and neuropathic and to prevent restenosis. These compounds are different in structure to the compounds of the current invention.
WO 2001012186 (Biogen, Inc.) discloses (2S)-4-[[(2S)-4-methyl-2-[methyl[[4-[[[2-methylphenyl)amino]carbonyl]amino]phenyl]acetyl]amino]-1-oxopentyl]amino]-2-[[[(3S)-1-(phenylsulfonyl)-3-piperidinyl]carbonyl]amino]-butanoic acid as a cell adhesion inhibitor. This compound is different in structure to the compounds of the current invention.
WO 2001007440 (Boehringer Ingelheim Pharmaceuticlas, Inc.) discloses 1-[[(3R)-3-[(4-bromophenyl)methyl]-1-(3,5-dichlorophenyl)-2,3-dihydro-3-methyl-2-oxo-1H-imidazo[1,2-a]imidazol-5-yl]sulfonyl]-N,N-diethyl-3-piperidinecarboxamide as an anti-inflammatory agent.
WO 2000048623 (Kaken Pharmaceutical Co., Ltd) discloses N-[(1R)-2-[(3-aminopropyl)amino]-1-(2-naphthalenylmethyl)-2-oxoethyl]-1-(phenylsulfonyl)-3-piperidinecarboxamide, monohydrochloride (9CI) as a growth hormone.
U.S. Pat. No. 5,817,678 (Merck & Co., Inc.) discloses (3S)—N-[2-[1-[(4-cyanophenyl)methyl]-1H-imidazol-5-yl]ethyl]-1-(phenylsulfonyl)-3-piperidinecarboxamide, (3S)—N-[2-[1-[(4-cyanophenyl)methyl]-1H-imidazol-5-yl]ethyl]-1-(naphthalenesulfonyl)-3-piperidinecarboxamide, (3S)-1-[(3-chlorophenyl)sulfonyl]-N-[2-[1-[(4-cyanophenyl)methyl]-1H-imidazol-5-yl]ethyl]-3-piperidinecarboxamide, and (3S)—N-[2-[1-[(4-cyanophenyl)methyl]-1H-imidazol-5-yl]ethyl]-1-[(3,5-dichlorophenyl)sulfonyl]-3-piperidinecarboxamide as farnesyl-protein transferase inhibitors.
WO 9910523, WO 9910524, WO 9910525 and WO 2000016626 (Merck & Co., Inc.) also disclose (3S)—N-[2-[1-[(4-cyanophenyl)methyl]-1H-imidazol-5-yl]ethyl]-1-[(3,5-dichlorophenyl)sulfonyl]-3-piperidinecarboxamide as an inhibitor of prenyl protein transferases for cancer treatment.
Scozzafava et al. Eur. J. Med. Chem. 2000, 35, 31 discloses N-[2-(1H-imidazol-4-yl)ethyl]-1-[(4-methylphenyl)sulfonyl]-3-piperidinecarboxamide as an activator of carbonic anhydrase isoenzymes I, II and IV.
DE 19827640 (Bayer A.-G.) discloses 1-[[3-(7-cyclopentyl-1,4-dihydro-5-methyl-4-oxoimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxyphenyl]sulfonyl]-N,N-diethyl-3-piperidinecarboxamide, 1-[[3-(7-cycloheptyl-1,4-dihydro-5-methyl-4-oxoimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxyphenyl]sulfonyl]-N,N-diethyl-3-piperidinecarboxamide, and, 1-[[4-ethoxy-3-(7-hexyl-1,4-dihydro-5-methyl-4-oxoimidazo[5,1-f][1,2,4]triazin-2-yl)phenyl]sulfonyl]-N,N-diethyl-3-piperidinecarboxamide as phosphodiesterase inhibitors
WO 9964004 (Bristol-Myers Squibb Company) discloses 1-[[1-[[3-(5,8-dihydro-8-oxo-1H-imidazo[4,5-g]quinazolin-6-yl)-4-propoxyphenyl]sulfonyl]-3-piperidinyl]carbonyl]-4-methyl-piperazine as an inhibitor of cGMP phosphodiesterase.
A need exits in the art, however, for additional 11β-HSD1 inhibitors that have efficacy for the treatment of diseases such as type II diabetes mellitus and metabolic syndrome. Further, a need exists in the art for 11β-HSD1 inhibitors having IC50 values less than about 1 μM.
In one embodiment of the present invention, a pharmaceutical composition comprising a therapeutically effective amount of a compound according to formula (I) is provided:
wherein
In another embodiment of the present invention, a method for the treatment of type II diabetes in a patient in need thereof is provided, comprising administering to said patient a therapeutically effective amount of a compound according to formula (I).
The present invention pertains to inhibitors of 11β-HSD1. In a preferred embodiment, the invention provides for pharmaceutical compositions comprising sulfonyl piperidines of the formula I:
as well as pharmaceutically acceptable salts thereof, that are useful as inhibitors of 11β-HSD1.
It is to be understood that the terminology employed herein is for the purpose of describing particular embodiments, and is not intended to be limiting. Further, although any methods, devices and materials similar or equivalent to those described herein can be used in the practice or testing of the invention, the preferred methods, devices and materials are now described.
In this specification the term “aryl” is used to mean a mono- or polycyclic aromatic ring system, in which the rings may be carbocyclic or may contain one or more atoms selected from O, S, and N. Examples of aryl groups are phenyl, pyridyl, benzimidazolyl, benzofuranyl, benzothiazolyl, benzothiophenyl, cinnolinyl, furyl, imidazo[4,5-c]pyridinyl, imidazolyl, indolyl, isoquinolinyl, isoxazolyl, naphthyl, [1,7]naphthyridinyl, oxadiazolyl, oxazolyl, phthalazinyl, purinyl, pyidazinyl, pyrazolyl, pyrido[2,3-d]pyrimidinyl, pyrimidinyl, pyrimido[3,2-c]pyrimidinyl, pyrrolo[2,3-d]pyrimidinyl, pyrrolyl, quinazolinyl, quinolinyl, quinoxalinyl, tetrazolyl, thiadiazolyl, thiazolyl, thiophenyl, triazolyl, and the like.
As used herein, the term “alkyl” means, for example, a branched or unbranched, cyclic or acyclic, saturated or unsaturated (e.g. alkenyl or alkynyl) hydrocarbyl radical which may be substituted or unsubstituted. Where cyclic, the alkyl group is preferably C3 to C12, more preferably C5 to C10, more preferably C5 to C7. Where acyclic, the alkyl group is preferably C1 to C10, more preferably C1 to C6, more preferably methyl, ethyl, propyl (n-propyl or isopropyl), butyl (n-butyl, isobutyl or tertiary-butyl) or pentyl (including n-pentyl and isopentyl), more preferably methyl. It will be appreciated therefore that the term “alkyl” as used herein includes alkyl (branched or unbranched), substituted alkyl (branched or unbranched), alkenyl (branched or unbranched), substituted alkenyl (branched or unbranched), alkynyl (branched or unbranched), substituted alkynyl (branched or unbranched), cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, cycloalkynyl and substituted cycloalkynyl.
As used herein, the term “lower alkyl” means, for example, a branched or unbranched, cyclic or acyclic, saturated or unsaturated (e.g. alkenyl or alkynyl) hydrocarbyl radical wherein said cyclic lower alkyl group is C5, C6 or C7, and wherein said acyclic lower alkyl group is C1, C2, C3 or C4, and is preferably selected from methyl, ethyl, propyl (n-propyl or isopropyl) or butyl (n-butyl, sec-butyl, isobutyl or tertiary-butyl). It will be appreciated therefore that the term “lower alkyl” as used herein includes lower alkyl (branched or unbranched), lower alkenyl (branched or unbranched), lower alkynyl (branched or unbranched), cycloloweralkyl, cycloloweralkenyl and cycloloweralkynyl.
The alkyl and aryl groups may be substituted or unsubstituted. Where substituted, there will generally be, for example, 1 to 3 substituents present, preferably 1 substituent. Substituents may include, for example: carbon-containing groups such as alkyl, aryl, arylalkyl (e.g. substituted and unsubstituted phenyl, substituted and unsubstituted benzyl); halogen atoms and halogen-containing groups such as haloalkyl (e.g. trifluoromethyl); oxygen-containing groups such as alcohols (e.g. hydroxyl, hydroxyalkyl, aryl(hydroxyl)alkyl), ethers (e.g. alkoxy, aryloxy, alkoxyalkyl, aryloxyalkyl), aldehydes (e.g. carboxaldehyde), ketones (e.g. alkylcarbonyl, alkylcarbonylalkyl, arylcarbonyl, arylalkylcarbonyl, arycarbonylalkyl), acids (e.g. carboxy, carboxyalkyl), acid derivatives such as esters(e.g. alkoxycarbonyl, alkoxycarbonylalkyl, alkylcarbonyloxy, alkylcarbonyloxyalkyl), amides (e.g. aminocarbonyl, mono- or di-alkylaminocarbonyl, aminocarbonylalkyl, mono-or di-alkylaminocarbonylalkyl, arylaminocarbonyl), carbamates (e.g. alkoxycarbonylamino, arloxycarbonylamino, aminocarbonyloxy, mono-or di-alkylaminocarbonyloxy, arylaminocarbonyloxy) and ureas (e.g. mono- or di-alkylaminocarbonylamino or arylaminocarbonylamino); nitrogen-containing groups such as amines (e.g. amino, mono- or di-alkylamino, aminoalkyl, mono- or di-alkylaminoalkyl), azides, nitriles (e.g. cyano, cyanoalkyl), nitro; sulfur-containing groups such as thiols, thioethers, sulfoxides and sulfones (e.g. alkylthio, alkylsulfinyl, alkylsulfonyl, alkylthioalkyl, alkylsulfinylalkyl, alkylsulfonylalkyl, arylthio, arysulfinyl, arysulfonyl, arythioalkyl, arylsulfinylalkyl, arylsulfonylalkyl); and heterocyclic groups containing one or more, preferably one, heteroatom, (e.g. thienyl, furanyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, oxazolyl, oxadiazolyl, thiadiazolyl, aziridinyl, azetidinyl, pyrrolidinyl, pyrrolinyl, imidazolidinyl, imidazolinyl, pyrazolidinyl, tetrahydrofuranyl, pyranyl, pyronyl, pyridyl, pyrazinyl, pyridazinyl, piperidyl, hexahydroazepinyl, piperazinyl, morpholinyl, thianaphthyl, benzofuranyl, isobenzofuranyl, indolyl, oxyindolyl, isoindolyl, indazolyl, indolinyl, 7-azaindolyl, benzopyranyl, coumarinyl, isocoumarinyl, quinolinyl, isoquinolinyl, naphthridinyl, cinnolinyl, quinazolinyl, pyridopyridyl, benzoxazinyl, quinoxalinyl, chromenyl, chromanyl, isochromanyl, phthalazinyl and carbolinyl).
The lower alkyl groups may be substituted or unsubstituted, preferably unsubstituted. Where substituted, there will generally be, for example, 1 to 3 substitutents present, preferably 1 substituent.
As used herein, the term “alkoxy” means, for example, alkyl-O— and “alkoyl” means, for example, alkyl-CO—. Alkoxy substituent groups or alkoxy-containing substituent groups may be substituted by, for example, one or more alkyl groups.
As used herein, the term “halogen” means, for example, a fluorine, chlorine, bromine or iodine radical, preferably a fluorine, chlorine or bromine radical, and more preferably a fluorine or chlorine radical.
As used herein, the term “pharmaceutically acceptable salt” means any pharmaceutically acceptable salt of the compound of formula (I). Salts may be prepared from pharmaceutically acceptable non-toxic acids and bases including inorganic and organic acids and bases. Such acids include, for example, acetic, benzenesulfonic, benzoic, camphorsulfonic, citric, ethenesulfonic, dichloroacetic, formic, fumaric, gluconic, glutamic, hippuric, hydrobromic, hydrochloric, isethionic, lactic, maleic, malic, mandelic, methanesulfonic, mucic, nitric, oxalic, pamoic, pantothenic, phosphoric, succinic, sulfuric, tartaric, oxalic, p-toluenesulfonic and the like. Particularly preferred are fumaric, hydrochloric, hydrobromic, phosphoric, succinic, sulfuric and methanesulfonic acids. Acceptable base salts include alkali metal (e.g. sodium, potassium), alkaline earth metal (e.g. calcium, magnesium) and aluminum salts.
The compounds of the present invention can be prepared by any conventional means. Suitable processes for synthesizing these compounds are provided in the examples. Generally, compounds of formula I can be prepared according to Scheme 1, Scheme 2 or Scheme 3 (see below). The sources of the starting materials for these reactions are also described.
Compounds of formula 1 can be prepared from nipecotic acid (2) according to Scheme 1 by sulfonylation to give a sulfonamide of formula 4 followed by an amide coupling reaction to give the compound of formula 1. The first reaction can be carried out by reacting the compound of formula 2 with a sulfonyl chloride of formula 3 in an inert solvent such as a halogenated hydrocarbon (such as methylene chloride) or an ether (such as tetrahydrofuran or dioxane) or an ester solvent such as ethyl acetate. The reaction is conveniently carried out in the presence of an organic base (such as triethylamine or diisopropylethylamine) or an inorganic base (such as sodium hydroxide or sodium carbonate). When an inorganic base is used, the reaction is conveniently carried out in the additional presence of water, and the co-solvent should be stable to the aqueous base. The reaction can be carried out at a temperature between about 0 degrees and about room temperature, preferably at around room temperature.
Additionally, a number of aryl-sulfonyl-nipecotic acid derivatives of formula 4 are available commercially, and some of these are shown in the table:
The coupling of carboxylic acids of formula 4 with amines of formula 5, according to Scheme 1, can be achieved using methods well known to one of ordinary skill in the art. For example, the transformation can be carried out by reaction of carboxylic acids of formula 4 or of appropriate derivatives thereof such as activated esters, with amines of formula 5 or their corresponding acid addition salts (e.g., the hydrochloride salts) in the presence, if necessary, of a coupling agent, many examples of which are well known per se in peptide chemistry. The reaction is conveniently carried out by treating the carboxylic acid of formula 4 with the hydrochloride of the amine of formula 5 in the presence of an appropriate base, such as diisopropylethylamine, a coupling agent such as O-(benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate, and in the optional additional presence of a substance that increases the rate of the reaction, such as 1-hydroxybenzotriazole or 1-hydroxy-7-azabenzotriazole, in an inert solvent, such as a chlorinated hydrocarbon (e.g., dichloromethane) or N,N-dimethylformamide or N-methylpyrrolidinone, at a temperature between about 0 degrees and about room temperature, preferably at about room temperature. Alternatively, the reaction can be carried out by converting the carboxylic acid of formula 4 to an activated ester derivative, such as the N-hydroxysuccinimide ester, and subsequently reacting this with the amine of formula 5 or a corresponding acid addition salt. This reaction sequence can be carried out by reacting the carboxylic acid of formula 4 with N-hydroxysuccinimide in the presence of a coupling agent such as N,N′-dicyclohexylcarbodiimide in an inert solvent such as tetrahydrofuran at a temperature between about 0 degrees and about room temperature. The resulting N-hydroxysuccinimide ester is then treated with the amine of formula 5 or a corresponding acid addition salt, in the presence of a base, such as organic base (e.g., triethylamine or diisopropylethylamine or the like) in a suitable inert solvent such as N,N-dimethylformamide at around room temperature.
Compounds of the invention of formula 1 can also be prepared according to Scheme 2, which differs from Scheme 1 in the order of the incorporation of the aryl-sulfonyl and amine groups into the molecule. In this process, the nitrogen of the compound of formula 2 is protected to give a compound of formula 6 where PG represents a protective group, many appropriate examples of which are known to one of skill in the art, as discussed below. The compound of formula 6 is then converted to an amide of formula 7, the protective group is then cleaved to give an amine of formula 8 and this compound is then reacted with a sulfonyl chloride of formula 3 to give the compound of formula 1. It will be readily apparent to one of skill in the art that Scheme 2 affords the possibility to prepare compounds of the invention in which one of R1 or R2 represents hydrogen on solid-phase by using a resin-bound amine 5.
Many protective groups PG are known to those of skill in the art of organic synthesis. For example, several suitable protective groups are enumerated in “Protective Groups in Organic Synthesis” [Greene, T. W. and Wuts, P. G. M., 2nd Edition, John Wiley & Sons, N.Y. 1991]. Preferred protective groups are those compatible with the reaction conditions used to prepare compounds of the invention. Examples of such protective groups are tert-butoxycarbonyl (Boc), benzyloxycarbonyl (Cbz), and 9-fluorenylmethoxycarbonyl (Fmoc).
Some examples of intermediates of formula 6 are available commercially, as shown in the table below. Further examples of intermediates of formula 6 can be prepared as described in the subsequent paragraph.
Intermediates of formula 6 can be prepared by reacting the compound of formula 2 with an alkoxycarbonylating reagent such as di-tert-butyl dicarbonate, 2-(tert-butoxycarbonyloxyimino)-2-phenylacetonitrile, benzyl chloroformate, 9-fluorenylmethyl pentafluorophenyl carbonate, N-(9-fluorenylmethoxycarbonyloxy)succinimide, or the like, in the presence of a base which may be organic (for example, triethylamine) or inorganic (for example, sodium hydroxide, sodium or potassium carbonate, or sodium hydrogen carbonate) in an inert solvent such as water or dioxane or tetrahydrofuran, or in a mixture of inert solvents such as a mixture of water and acetone, water and dioxane, or water and tetrahydrofuran. The reaction is conveniently carried out at a temperature between about 0 degrees and about room temperature, preferably at about room temperature. Where the intermediate of formula 6 is not stable to basic conditions, as in the case of a compound of formula 6 in which PG represents Fmoc (9-fluorenylmethoxycarbonyl), care should be taken that this intermediate is not exposed to strongly basic conditions during attempts to prepare it. It will be readily apparent to one of skill in the art that the selection of protective group depends on the nature of the target compound 1, so that for example, the functionalities present in the NR1R2 moiety are compatible with the conditions used to accomplish the removal of the protective group in the conversion of the compound of formula 7 to the compound of formula 8. Because there exist a number of different choices for the protective group PG, with complementary methods of deprotection, there is no difficulty in selecting a protective group for the synthesis of any of the compounds of the invention according to Scheme 2.
The coupling of a carboxylic acid of formula 6 with an amine of formula 5, according to Scheme 2, can be achieved using methods well known to one of ordinary skill in the art. For example, the transformation can be carried out by reaction of a carboxylic acid of formula 6 or of an appropriate derivative thereof such as an activated ester, with an amine of formula 5 or its corresponding acid addition salt (e.g., the hydrochloride salt) in the presence, if necessary, of a coupling agent, many examples of which are well known per se in peptide chemistry. The reaction is conveniently carried out by treating the carboxylic acid of formula 6 with the hydrochloride of the amine of formula 5 in the presence of an appropriate base, such as diisopropylethylamine, a coupling agent such as O-(benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate, and in the optional additional presence of a substance that increases the rate of the reaction, such as 1-hydroxybenzotriazole or 1-hydroxy-7-azabenzotriazole, in an inert solvent, such as a chlorinated hydrocarbon (e.g., dichloromethane) or N,N-dimethylformamide or N-methylpyrrolidinone, at a temperature between about 0 degrees and about room temperature, preferably at about room temperature. Alternatively, the reaction can be carried out by converting the carboxylic acid of formula 6 to an activated ester derivative, such as the N-hydroxysuccinimide ester, and subsequently reacting this with the amine of formula 5 or a corresponding acid addition salt. This reaction sequence can be carried out by reacting the carboxylic acid of formula 6 with N-hydroxysuccinimide in the presence of a coupling agent such as N,N′-dicyclohexylcarbodiimide in an inert solvent such as tetrahydrofuran at a temperature between about 0 degrees and about room temperature. The resulting N-hydroxysuccinimide ester is then treated with the amine of formula 5 or a corresponding acid addition salt, in the presence of a base, such as organic base (e.g., triethylamine or diisopropylethylamine or the like) in a suitable inert solvent such as N,N-dimethylformamide at around room temperature.
The removal of the protective group in the conversion of the compound of formula 7 to the amine of formula 8 is carried out according to procedures that are well known in the arts of synthetic chemistry and peptide chemistry and which depend on the nature of the protective group PG. Many examples of suitable procedures are listed in “Protective Groups in Organic Synthesis” [Greene, T. W. and Wuts, P. G. M., 2nd Edition, John Wiley & Sons, N.Y. 1991]. For example, in the case where the protective group is Fmoc (9-fluorenylmethoxycarbonyl), the group can be conveniently removed by treating the compound of formula 7 with an organic base (such as piperidine, morpholine, or ethanolamine) in an inert solvent such as N,N-dimethylformamide or dichloromethane at about room temperature. In the case where the protective group is benzyloxycarbonyl (Cbz), the group can be removed under hydrogenolytic conditions, for example by hydrogenation in the presence of a noble metal catalyst such as palladium-on-carbon, or palladium black, in the presence of an inert solvent (for example, an alcohol such as ethanol) at about room temperature and under atmospheric pressure, or at elevated pressure (such as 50 PSI of hydrogen) if required. As a further example, in the case where the protective group is tert-butoxycarbonyl (Boc), the group can be removed by treatment of the compound of formula 7 with acid (either organic or inorganic) in an inert solvent. For example, the Boc group can be removed by treatment of the compound of formula 7 with trifluoroacetic acid in dichloromethane at about room temperature, or it can be removed by treatment of the compound of formula 7 with hydrochloric acid in an alcoholic solvent (e.g., methanol or ethanol) or an ether (e.g., dioxane) or ethyl acetate, also at about room temperature.
The compound of formula 8 is conveniently converted to the compound of the invention of formula 1 by sulfonylation with a sulfonylating reagent of formula 3. The reaction can be carried out by reacting the compound of formula 8 with a sulfonyl chloride of formula 3 in an inert solvent such as a halogenated hydrocarbon (such as methylene chloride) or an ether (such as tetrahydrofuran or dioxane) or an ester solvent such as ethyl acetate. The reaction is conveniently carried out in the presence of an organic base (such as triethylamine or diisopropylethylamine) or an inorganic base (such as sodium hydroxide or sodium carbonate). When an inorganic base is used, the reaction is conveniently carried out in the additional presence of water, and the co-solvent should be stable to the aqueous base. The reaction can be carried out at a temperature between about 0 degrees and about room temperature, preferably at around room temperature. Many sulfonyl chlorides of formula 3 are commercially available, or can be synthesized according to the many different processes as discussed above.
In the case where a resin-bound amine of formula 5 was used, an additional step is required for the conversion of the resin-bound compound of formula 1 into the compound of the invention; namely, the compound of the invention must be cleaved from the resin. This can be done using any conventional conditions, many of which are known to one of skill in the art of solid-phase organic synthesis, and which conditions will depend on the nature of the linker attaching the product to the solid support. For example, in the case where FMBP resin was used, the cleavage is conveniently effected by treating the resin-bound compound of formula 1 with an organic acid, preferably trifluoroacetic acid, in an inert solvent such as dichloromethane at room temperature.
Compounds of the invention of formula 1 can also be prepared according to Scheme 3, which differs from Scheme 1 in that there are an additional two steps in the sequence—a protection step and a deprotection step. In this process, the carboxyl group of the compound of formula 2 is protected to give a compound of formula 9 where R3 represents a protective group, many appropriate examples of which are known to one of skill in the art, as discussed below. The compound of formula 9 is then converted to sulfonamide of formula 10, the protective group is then cleaved to give a carboxylic acid of formula 4 and this compound is then coupled with an amine of formula 5 to give the compound of formula 1. It will be appreciated by one of skill in the art that Scheme 3 affords the possibility to carry out the sulfonylation reaction (the conversion of a compound of formula 9 to a compound of formula 10) on solid-phase by using a polymer-supported R3 group.
Many protective groups R3 are known to those of skill in the art of organic synthesis. For example, several suitable protective groups are enumerated in “Protective Groups in Organic Synthesis” [Greene, T. W. and Wuts, P. G. M., 2nd Edition, John Wiley & Sons, N.Y. 1991]. Preferred protective groups are those compatible with the reaction conditions used to prepare compounds of the invention. Examples of such protective groups are lower alkyl straight-chain or branched esters (e.g., methoxy (R3═OCH3), ethoxy (R3═OCH2CH3), or tert-butoxy (R3═OC(CH3)3) esters), or the benzyl ester (R3═OCH2C6H5), or a resin commonly used in solid-phase synthesis (e.g., Wang resin or Rink resin), and these can be made by any conventional methods. For example, they may conveniently be made from the corresponding carboxylic acid of formula 2 by any esterification reaction, many of which are well known to one of ordinary skill in the art. For example, a compound of formula 9 in which R3 represents methoxy can be prepared from a compound of formula 2 by treatment with an ethereal solution of diazomethane. The reaction is conveniently carried out in an inert solvent such as an ether (e.g., diethyl ether or tetrahydrofuran) or an alcohol (e.g., methanol), at a temperature of between about 0 degrees and about room temperature, preferably at about 0 degrees. In the case where R3 represents the Wang resin, the compound of formula 9 is conveniently prepared by treating the resin with the compound of formula 2 in the presence of a coupling agent (such as diisopropylcarbodiimide) and in the presence of a catalytic amount of N,N-dimethylaminopyridine (DMAP) in an inert solvent such as N,N-dimethylformamide at about room temperature.
The sulfonylation reaction can be carried out by reacting the compound of formula 9 with a sulfonyl chloride of formula 3 in an inert solvent such as a halogenated hydrocarbon (such as methylene chloride) or an ether (such as tetrahydrofuran or dioxane) or an ester solvent such as ethyl acetate. The reaction is conveniently carried out in the presence of an organic base (such as triethylamine or diisopropylethylamine) or an inorganic base (such as sodium hydroxide or sodium carbonate). When an inorganic base is used, the reaction is conveniently carried out in the additional presence of water, and the co-solvent and protective group should be stable to the aqueous base. The reaction can be carried out at a temperature between about 0 degrees and about room temperature, preferably at around room temperature. Many sulfonyl chlorides of formula 3 are commercially available, or can be synthesized according to many different processes as discussed above.
For the removal of the protective group from a compound of formula 10 to give the carboxylic acid of formula 4, any conventional means can be used. For example, in the case where R3 represents an unbranched lower alkoxy group (e.g., methoxy), the reaction may be carried out by treating the compound of formula 10 with an alkali methyl hydroxide, such as potassium hydroxide, sodium hydroxide or lithium hydroxide, preferably lithium hydroxide, in an appropriate solvent, such as a mixture of tetrahydrofuran, methanol and water. The reaction is conveniently carried out at a temperature between about 0 degrees and about room temperature, preferably at about room temperature. In the case where R3 represents Wang resin or Rink resin, the cleavage can be effected using trifluoroacetic acid in dichloromethane at about room temperature.
The coupling of a carboxylic acid of formula 4 with an amine of formula 5 to give the compound of the invention of formula 1 according to Scheme 3, can be achieved as mentioned above, using methods well known to one of ordinary skill in the art. For example, the transformation can be carried out by reaction of carboxylic acids of formula 4 or of appropriate derivatives thereof such as activated esters, with amines of formula 5 or their corresponding acid addition salts (e.g., the hydrochloride salts) in the presence, if necessary, of a coupling agent, many examples of which are well known per se in peptide chemistry. The reaction is conveniently carried out by treating the carboxylic acid of formula 4 with the hydrochloride of the amine of formula 5 in the presence of an appropriate base, such as diisopropylethylamine, a coupling agent such as O-(benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate, and in the optional additional presence of a substance that increases the rate of the reaction, such as 1-hydroxybenzotriazole or 1-hydroxy-7-azabenzotriazole, in an inert solvent, such as a chlorinated hydrocarbon (e.g., dichloromethane) or N,N-dimethylformamide or N-methylpyrrolidinone, at a temperature between about 0 degrees and about room temperature, preferably at about room temperature. Alternatively, the reaction can be carried out by converting the carboxylic acid of formula 4 to an activated ester derivative, such as the N-hydroxysuccinimide ester, and subsequently reacting this with the amine of formula 5 or a corresponding acid addition salt. This reaction sequence can be carried out by reacting the carboxylic acid of formula 4 with N-hydroxysuccinimide in the presence of a coupling agent such as N,N′-dicyclohexylcarbodiimide in an inert solvent such as tetrahydrofuran at a temperature between about 0 degrees and about room temperature. The resulting N-hydroxysuccinimide ester is then treated with the amine of formula S or a corresponding acid addition salt, in the presence of a base, such as organic base (e.g., triethylamine or diisopropylethylamine or the like) in a suitable inert solvent such as N,N-dimethylformamide at around room temperature.
Racemic nipecotic acid is commercially from suppliers such as Aldrich Chemical Company, Inc., Milwaukee, Wisc.; TCI America, Portland, Oreg.; and Lancaster Synthesis Ltd., Lancashire, UK. The optically active nipecotic acids are also commercially available. For example, both (R)-(−)-nipecotic acid and (S)-(+)-nipecotic acid are available from the following suppliers:
In addition, the individual enantiomers of nipecotic acid can be prepared by chiral chromatography (see J. S. Valsborg and C. Foged, J. Labelled Compd. Radiopharm. 1997, 39, 401) or by resolution. The following publications describe methods for the preparation by resolution of (R)-(−)-nipecotic acid and (S)-(+)-nipecotic acid or their acid addition salts:
Sulfonyl chlorides of formula 3 can be purchased or they can be prepared using one of a large variety of different synthetic procedures well known in the field of organic synthesis, as outlined below. The synthetic approaches to sulfonyl chlorides are often complementary and offer access to sulfonyl chlorides with many different substitution patterns in the aryl ring system.
More than 100 sulfonyl chlorides of formula 3 are commercially available from suppliers such as Aldrich Chemical Company, Inc. (Milwaukee, Wisc.), Lancaster Synthesis Ltd. (Lancashire, UK), TCI America (Portland, Oreg.), and Maybridge plc (Tintagel, Cornwall, UK). For the purposes of illustration, a number of commercially available sulfonyl chlorides are shown in the table below. Many other examples can be found by consulting the Available Chemicals Directory (MDL Information Systems, San Leandro, Calif.) or SciFinder (Chemical Abstracts Service, Columbus, Ohio).
Sulfonyl chlorides of formula 3 can also be made by reactions that are well known in the field of organic synthesis, such as those outlined below.
For example, sulfonyl chlorides of formula 3 can be made from a sulfonic acid of formula 11 as shown in Scheme 4. The chlorination of an arylsulfonic acid, or a salt thereof, of formula 11 can be accomplished conveniently by treating it with a chlorinating agent such as thionyl chloride or phosphorus oxychloride or phosphorus pentachloride, in the optional additional presence of a catalytic amount of N,N-dimethylformamide, at a temperature between about 0 degrees and about 80 degrees depending on the reactivity of the chlorinating agent. Many examples of this reaction are known in the literature, such as those listed in the following table
Sulfonyl chlorides of formula 3 can be made by electrophilic aromatic substitution of an aromatic compound of formula 12 as shown in Scheme 5. As is known to one of average skill in the art, this process is suitable for the preparation of arylsulfonyl chlorides with particular substitution patterns, such as for example where there is an ortho/para directing substituent in a benzene ring ortho or para to the site of introduction of the sulfonyl group. The reaction is conveniently carried out by treating the aromatic compound of formula 12 with chlorosulfonic acid in the absence of solvent and then heating the mixture at a temperature between about 70 degrees and about 100 degrees. Many examples of this reaction are known in the literature, such as those listed in the following table
Sulfonyl chlorides of formula 3 can also be made from anilines of formula 13 by a diazotization/sulfonylation reaction sequence as shown in Scheme 6. The diazotization reaction is conveniently carried out by treating the aniline of formula 13 or an acid addition salt thereof (such as the hydrochloride salt) in aqueous solution in the presence of a mineral acid such as hydrochloric acid or sulfuric acid with an alkali metal nitrite salt such as sodium nitrite at a temperature less than 10 degrees, preferably around 0 degrees. The diazonium salt obtained in this way can be converted directly to the sulfonyl chloride using a variety of reagents and conditions which are known in the field of organic synthesis. Examples of suitable reagents include sulfur dioxide and copper(I) chloride or copper(II) chloride in acetic acid/water, or thionyl chloride and copper(I) chloride or copper(II) chloride in water, according to the procedure of P. J. Hogan (U.S. Pat. No. 6,531,605). For example, the sulfonylation reaction can be carried out by adding the solution of the diazonium salt, prepared as described above, to a mixture of sulfur dioxide and copper(II) chloride in a suitable inert solvent, such as glacial acetic acid, at a temperature around 0 degrees. Many examples of this reaction are known in the literature, such as those listed in the following table
Sulfonyl chlorides of formula 3 can also be made from an aryl benzyl sulfide of formula 14 by an oxidative chlorination reaction as shown in Scheme 7. The reaction is conveniently carried out by bubbling chlorine gas into a solution or suspension of the aryl benzyl sulfide of formula 14 in a suitable solvent such as a mixture of acetic acid and water at a temperature around room temperature.
Sulfonyl chlorides of formula 3 can also be made as shown in Scheme 8 from an aryl bromide of formula 15 by metal-halogen exchange, followed by reaction of the organometallic intermediate with sulfur dioxide to give an arylsulfonate salt, followed by reaction with sulfuryl chloride to give the arylsulfonyl chloride. The reaction can be carried out by treating the aryl bromide with an organometallic reagent such as n-butyl lithium or preferably sec-butyl lithium, in the optional additional presence of tetramethylethylenediamine (TMEDA) in a suitable inert solvent such as tetrahydrofuran (THF) or diethyl ether at low temperature (for example, around −78 degrees) to give the aryllithium intermediate. This can then be reacted, without isolation, with a mixture of sulfur dioxide and a solvent such as diethyl ether, again at low temperature, such as for example between about -78 degrees and about −60 degrees. The resulting arylsulfonate salt can then be converted to the arylsulfonyl chloride, again without isolation of the intermediate, by treatment with sulfuryl chloride at a temperature around 0 degrees. Many examples of this reaction are known in the literature, such as those listed in the following table
Sulfonyl chlorides of formula 3 can be made from an aryl thiol of formula 16 by oxidation using chlorine as shown in Scheme 9. For example, the reaction can be carried out by treating the aryl thiol of formula 16 with a solution of chlorine in an inert solvent such as glacial acetic acid at a temperature around 0 degrees. For example, 4-(1H-tetrazol-1-yl)phenyl]sulfonyl chloride could be prepared using this procedure from the thiophenol 4-(1H-tetrazol-1-yl)-benzenethiol which is known (W. V. Curran et al. U.S. Pat. No. 3,932,440). Several examples of this reaction are known in the literature, such as those listed in the following table
Sulfonyl chlorides of formula 3 can be made from a phenol of formula 17 through a sequence of reactions outlined in Scheme 10. The phenol of formula 17 can be converted to the O-aryl-N,N′-dialkylthiocarbamate of formula 18 by reaction with an N,N′-dialkylthiocarbamoyl chloride in an inert solvent in the presence of a base. The resulting O-aryl-N,N′-dialkylthiocarbamate of formula 18 can be rearranged to the S-aryl-N,N′-dialkylthiocarbamate of formula 19 by heating neat at high temperature such as at around 250 degrees. The S-aryl-N,N′-dialkylthiocarbamate of formula 19 can then be converted to the sulfonyl chloride of formula 3 by oxidation using chlorine in a suitable inert solvent such as a mixture of formic acid and water at a temperature around 0 degrees. An example of the use of this process for the preparation of sulfonyl chlorides can be seen in V. Percec et al. J. Org. Chem. 2001, 66, 2104.
Amines of formula 5 can be purchased or they can be prepared using one of a large variety of different synthetic procedures well known in the field of organic synthesis, as outlined below.
Several thousand amines of formula 5 are commercially available from suppliers such as Aldrich Chemical Company, Inc. (Milwaukee, Wisc.), Lancaster Synthesis Ltd. (Lancashire, UK), TCI America (Portland, Oreg.), and Maybridge plc (Tintagel, Cornwall, UK). Other examples of amines are found in the Available Chemicals Directory (MDL Information Systems, San Leandro, Calif.) or SciFinder (Chemical Abstracts Service, Columbus, Ohio).
Amines of formula 5 can also be made by reactions that are well known in the field of organic synthesis, such as those outlined in “Comprehensive Organic Transformations: A Guide to Functional Group Preparations” [R. C. Larock, VCH Publishers, Inc., N.Y. 1989, pages 385-438] and in “Advanced Organic Chemistry” [J. March, 3rd Edition, Wiley Interscience, NY, 1985].
Resin-bound amines of formula 5 in which R2 represents a resin to which an amine can be attached can be prepared by reactions that are familiar to one of average skill in the art of solid-phase organic synthesis. For example, an amine of formula 5 where R2 represent the FMPB resin can be prepared according to Scheme 11 by treating FMPB resin (20) with a primary amine of formula 21 in the presence of a reducing agent such as sodium triacetoxyborohydride in an inert solvent such as a halogenated hydrocarbon (such as 1,2-dichloroethane) at room temperature.
Some examples of amines that can be prepared by known methods are shown in the table below:
In addition, a series of aminomethylpyrazoles can be prepared using the reductive amination procedure described by Borch et al (R. F. Borch et al. J. Am. Chem. Soc. 1971, 93, 2897), starting from pyrazole-carboxaldehydes that are commercially available, as shown in the table below:
General Synthesis of Adamantanamines
Amines of formula 5 in which R1 represents hydrogen and R2 represents unsubstituted or substittued adamantane are either commercially available or can be made by methods that are well known to one of average skill in the art. Examples of commercially available adamantan-1-yl-amines are shown in the table below.
Amines of formula 5 in which R1 represents hydrogen and R2 represents unsubstituted or substituted adamantane which are not commercially available can be made using a number of different reactions known in the literature. For example, 2-adamantanamine derivatives can be prepared from the corresponding adamantan-2-ones by conversion of the ketone to the oxime followed by reduction to the amine. Such reactions can be carried out using the procedures described in K. Banert et al. Chem. Ber. 1986, 119, 3826-3841. 2-Adamantanamines can also be prepared from 4-alkyl-4-protoadamantanols by a Ritter reaction with acetonitrile in the presence of sulfuric acid to give the acetamide which is then hydrolyzed to give the 2-adamantanamine, as described in D. Lenoir et al. J. Org. Chem. 1971, 36, 1821-1826.
Adamantanamines can be prepared from the corresponding 1-adamantane-carboxamides using a Hoffmann rearrangement or similar reaction. A variety of conditions for effecting this reaction are known in the art, and there have been a number of publications disclosing the application of this reaction for the preparation of 1-adamantanamines. Among these are the hypervalent iodine-mediated Hoffmann rearrangement described in R. M. Moriarty et al. Synth. Commun. 1988, 18, 1179 and G. Loudon et al. J. Org Chem. 1984, 49, 4272-4276, and the hypochlorite-mediated reaction reported in G. L. Anderson et al. Synth. Commun. 1988, 18, 1967. 1-Adamantanamines can also be prepared using the Ritter reaction starting from the corresponding 1-adamantanol and treating with chloro-acetonitrile under acidic conditions, followed by hydrolysis of the amide. The preparation of 1-adamantanamine using such a process has been described by A. Jirgensons et al. in Synthesis 2000, 1709-1712. Alternatively, 1-adamantanamines can be prepared from the corresponding 1-bromo-adamantanes using either Ritter-like conditions followed by hydrolysis (see K. Gerzon et al. J. Med. Chem. 1963, 6, 760-763 or O. Cervinka et al. Collect. Czech Chem. Commun. 1974, 39, 1592-1588), or by reaction of the 1-bromo-adamantanes with acetamide followed by hydrolysis (see K. Gerzon et al. J. Med. Chem. 1967, 10, 603-606). The 1-bromo-adamantanes are readily available by bromination of the hydroxy-adamantanes using bromine/triphenylphosphine or from the adamantane using bromine (see J. G. Henkel et al. J. Med Chem. 1982, 25, 51-56). 1-Adamantanamines can also be prepared from the corresponding 1-adamantanols by displacement of the hydroxy group by azide under acidic conditions, followed by reduction of the azide (see T. Sasaki et al. J. Org. Chem. 1977, 42, 3741-3743).
In the practice of the method of the present invention, an effective amount of any one of the compounds of this invention or a combination of any of the compounds of this invention or a pharmaceutically acceptable salt thereof, is administered via any of the usual and acceptable methods known in the art, either singly or in combination. The compounds or compositions can thus be administered orally (e.g., buccal cavity), sublingually, parenterally (e.g., intramuscularly, intravenously, or subcutaneously), rectally (e.g., by suppositories or washings), transdermally (e.g., skin electroporation) or by inhalation (e.g., by aerosol), and in the form or solid, liquid or gaseous dosages, including tablets and suspensions. The administration can be conducted in a single unit dosage form with continuous therapy or in a single dose therapy ad libitum. The therapeutic composition can also be in the form of an oil emulsion or dispersion in conjunction with a lipophilic salt such as pamoic acid, or in the form of a biodegradable sustained-release composition for subcutaneous or intramuscular administration.
Useful pharmaceutical carriers for the preparation of the compositions hereof, can be solids, liquids or gases; thus, the compositions can take the form of tablets, pills, capsules, suppositories, powders, enterically coated or other protected formulations (e.g. binding on ion-exchange resins or packaging in lipid-protein vesicles), sustained release formulations, solutions, suspensions, elixirs, aerosols, and the like. The carrier can be selected from the various oils including those of petroleum, animal, vegetable or synthetic origin, e.g., peanut oil, soybean oil, mineral oil, sesame oil, and the like. Water, saline, aqueous dextrose, and glycols are preferred liquid carriers, particularly (when isotonic with the blood) for injectable solutions. For example, formulations for intravenous administration comprise sterile aqueous solutions of the active ingredient(s) which are prepared by dissolving solid active ingredient(s) in water to produce an aqueous solution, and rendering the solution sterile. Suitable pharmaceutical excipients include starch, cellulose, talc, glucose, lactose, gelatin, malt, rice, flour, chalk, silica, magnesium stearate, sodium stearate, glycerol monostearate, sodium chloride, dried skim milk, glycerol, propylene glycol, water, ethanol, and the like. The compositions may be subjected to conventional pharmaceutical additives such as preservatives, stabilizing agents, wetting or emulsifying agents, salts for adjusting osmotic pressure, buffers and the like. Suitable pharmaceutical carriers and their formulation are described in Remington's Pharmaceutical Sciences by E. W. Martin. Such compositions will, in any event, contain an effective amount of the active compound together with a suitable carrier so as to prepare the proper dosage form for proper administration to the recipient.
The dose of a compound of the present invention depends on a number of factors, such as, for example, the manner of administration, the age and the body weight of the subject, and the condition of the subject to be treated, and ultimately will be decided by the attending physician or veterinarian. Such an amount of the active compound as determined by the attending physician or veterinarian is referred to herein, and in the claims, as an “effective amount”. For example, the dose of a compound of the present invention is typically in the range of about 10 to about 1000 mg per day.
The invention will now be further described in the Examples below, which are intended as an illustration only and do not limit the scope of the invention.
The following reagents were obtained from the vendors listed in the table, unless otherwise indicated in the experimental descriptions.
Chlorobenzenesulfonyl chloride (0.25 mL, 1.8 mmol) was added to a solution of (R)-(+)-nipecotic acid ethyl ester (available from Aldrich Chemical Company; Inc., Milwaukee, Wisc.; 250 mg, 1.6 mmol) and triethylamine (0.5 mL, 3.6 mmol) in dichloromethane (5 mL) under argon. An additional portion of dichloromethane (10 mL) was added and the solution was stirred for five days at room temperature. The reaction mixture was washed with water and the water layer was back-extracted with dichloromethane. The combined organic layers were washed with 80% saturated brine, dried (magnesium sulfate), filtered and evaporated to give (3R)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid ethyl ester (561 mg) as a colorless viscous oil, which was used directly in the next step. NMR indicated the presence of the desired product along with a small amount of dichloromethane.
1 M Aqueous lithium hydroxide solution (3.5 mL) was added to a solution of (3R)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid ethyl ester (from Step 1; 560 mg) in tetrahydrofuran (10 mL). The reaction mixture was stirred overnight at room temperature, the solvent was evaporated, the residue was diluted with water and the solution was acidified to pH 1. The solution was extracted three times with ethyl acetate, and the combined organic layers were washed with 80% saturated brine, dried (magnesium sulfate), filtered and evaporated to give (3R)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (450 mg, 92%) as a colorless semisolid.
(3S)-1-(2-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid was prepared from 2-chlorobenzenesulfonyl chloride and (S)-(+)-nipecotic acid ethyl ester (available from Aldrich Chemical Company, Inc., Milwaukee, Wisc.; 166 mg, 1.1 mmol) using the procedure described for the preparation of Intermediate A1.
(rac)-1-(2-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid was prepared from 2-chlorobenzenesulfonyl chloride and (rac)-nipecotic acid ethyl ester using the procedure described for the preparation of Intermediate A1.
(3R)-1-(4-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid was prepared from 4-chlorobenzenesulfonyl chloride and (R)-(+)-nipecotic acid ethyl ester (available from Aldrich Chemical Company, Inc., Milwaukee, Wisc.) using the procedure described for the preparation of Intermediate A1.
(3S)-1-(2,4-Dichloro-benzenesulfonyl)-piperidine-3-carboxylic acid was prepared from 2,4-dichlorobenzenesulfonyl chloride and (S)-(−)-nipecotic acid ethyl ester (available from Aldrich Chemical Company, Inc., Milwaukee, Wisc.) using the procedure described for the preparation of Intermediate A1.
(3S)-1-(4-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid was prepared from 4-chlorobenzenesulfonyl chloride and (S)-(−)-nipecotic acid ethyl ester (available from Aldrich Chemical Company, Inc., Milwaukee, Wisc.) using the procedure described for the preparation of Intermediate A1.
(3R)-1-(Thiophene-2-sulfonyl)-piperidine-3-carboxylic acid was prepared from thiophene-2-sulfonyl chloride and (R)-(+)-nipecotic acid ethyl ester (available from Aldrich Chemical Company, Inc., Milwaukee, Wisc.; 166 mg, 1.1 mmol) using the procedure described for the preparation of Intermediate A1, with the following modification. A second equivalent of thiophene-2-sulfonyl chloride from a different bottle and a second equivalent of triethylamine were added to the reaction mixture because it was determined by NMR that the sulfonyl chloride had hydrolyzed.
(3S)-1-(Thiophene-2-sulfonyl)-piperidine-3-carboxylic acid was prepared from thiophene-2-sulfonyl chloride and (S)-(+)-nipecotic acid ethyl ester (available from Aldrich Chemical Company, Inc., Milwaukee, Wisc.; 166 mg, 1.1 mmol) using the procedure described for the preparation of Intermediate A1, with the following modification. A second equivalent of thiophene-2-sulfonyl chloride from a different bottle and a second equivalent of triethylamine were added to the reaction mixture because it was determined by NMR that the sulfonyl chloride had hydrolyzed.
A solution of 2-methylcyclopentanone (11 mL, 100 mmol), hydroxylamine hydrochloride (17.76 g, 250 mmol), and triethylamine (42.5 mL, 300 mmol) in ethanol (150 mL) was heated at reflux overnight. The solvent was evaporated and the residue was diluted with water and acidified to pH 1. The mixture was extracted three times with ethyl acetate, and the combined organic layers were washed with water and brine, dried (magnesium sulfate), filtered and evaporated to give 2-methylcyclopentanone oxime (10 g, 88%) as a pale yellow oil.
A solution of ethanolic HCl was prepared by adding acetyl chloride (2 mL) to ethanol (100 mL) at 5 degrees, then removing the cooling bath and allowing the solution to stir for 1 h at room temperature. 2-Methylcyclopentanone oxime (from Step 1, 550 mg) was added to this solution along with 10% palladium-on-carbon (two spatulas-full). The mixture was hydrogenated overnight at atmospheric pressure, and then filtered through Celite. The Celite was washed well with ethanol, and the solvents were removed under vacuum. Recrystallization from ethyl acetate gave 2-methyl-cyclopentylamine hydrochloride as a brown solid (330 mg, 50%).
Isoamylamine (0.12 mL, 1.0 mmol) was added to a solution of (3S)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A1; 248 mg, 0.8 mmol), 1-hydroxybenzotriazole hydrate (146 mg, 1.1 mmol), N,N-dimethylaminopyridine (202 mg, 1.7 mmol), and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (205 mg, 1.1 mmol) in dichloromethane (10 mL). The solution was stirred at room temperature for 5 days, and then diluted with dichloromethane, washed with 1 M HCl (20 mL) and then brine (30 mL), dried (magnesium sulfate), filtered and evaporated. The crude product was purified using an Isco Sg100c RS-40 column, eluting with 15-50% ethyl acetate/hexanes to give (3S)-1-(2-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (3-methyl-butyl)-amide (192 mg, 64%) as a white solid. Mass spectrum (ES) MH+=373.
(3R)-1-(2-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (3-methyl-butyl)-amide was prepared from (3R)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A2) and isoamylamine using the procedure described for the preparation of Example 1. White solid. Yield: 74%. Mass spectrum (ES) MH+=373.
(3R)-1-(2-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (3-methyl-butyl)-amide was prepared from (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A3) and 4-hydroxypiperidine using the procedure described for the preparation of Example 1. White solid. Yield: 67%. Mass spectrum (ES) MH+=387.
(3R)-1-(Thiophene-2-sulfonyl)-piperidine-3-carboxylic acid cyclopentylamide was prepared from (3R)-1-(thiophene-2-sulfonyl)-piperidine-3-carboxylic acid (of Intermediate A7) and cyclopentylamine using the procedure described for the preparation of Example 1. Off-white solid. Yield: 73%. Mass spectrum (ES) MH+=343.
(3S)-1-(Thiophene-2-sulfonyl)-piperidine-3-carboxylic acid cyclopentylamide was prepared from (3S)-1-(thiophene-2-sulfonyl)-piperidine-3-carboxylic acid (of Intermediate A8) and cyclopentylamine using the procedure described for the preparation of Example 1. Off-white solid. Yield: 73%. Mass spectrum (ES) MH+=343.
(3R)-1-(4-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid cyclopentylamide was prepared from (3R)-1-(4-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A4) and cyclopentylamine using the procedure described for the preparation of Example 1. White solid. Yield: 80%. Mass spectrum (ES) MH+=371.
(3S)-1-(4-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid cyclopentylamide was prepared from (3S)-1-(4-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A4) and cyclopentylamine using the procedure described for the preparation of Example 1. White solid. Yield: 69%. Mass spectrum (ES) MH+=371.
(rac)-[1-(2-Chloro-benzenesulfonyl)-piperidin-3-yl]-(octahydro-quinolin-1-yl)-methanone was prepared from (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A3) and decahydroquinoline using the procedure described for the preparation of Example 1. White solid. Yield: 87%. Mass spectrum (ES) MH+=425.
(rac)-Azepan-1-yl-[1-(2-chloro-benzenesulfonyl)-piperidin-3-yl]-methanone was prepared from (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A3) and hexamethyleneimine using the procedure described for the preparation of Example 1. White solid. Yield: 65%. Mass spectrum (ES) MH+=385.
(rac)-[1-(2-Chloro-benzenesulfonyl)-piperidin-3-yl]-(4-methyl-piperidin-1-yl)-methanone was prepared from (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A3) and 4-methylpiperidine using the procedure described for the preparation of Example 1. White solid. Yield: 77%. Mass spectrum (ES) MH+=385.
(rac)-[1-(2-Chloro-benzenesulfonyl)-piperidin-3-yl]-(4,4-dimethyl-piperidin-1-methanone was prepared from (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A3) and 4,4-dimethylpiperidine (prepared by the reduction of 3,3-dimethyl-glutarimide using lithium aluminum hydride; see D. Hoch and P. Karrer Helv. Chim. Acta 1954, 37, 397) using the procedure described for the preparation of Example 1. White solid. Yield: 82%. Mass spectrum (ES) MH+=399.
(3S)-1-(2,4-Dichloro-benzenesulfonyl)-piperidine-3-carboxylic acid cyclopentylamide was prepared from (3S)-1-(2,4-dichloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A5) and cyclopentylamine using the procedure described for the preparation of Example 1. White solid. Yield: 60%. Mass spectrum (ES) MH+=405.
(3S)-1-(2-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid adamantan-1-ylamide was prepared from (3S)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A2) and 1-adamantanamine using the procedure described for the preparation of Example 1. White solid. Yield: 86%. Mass spectrum (ES) MH+=437.
(3 S)-(7-Aza-bicyclo[2.2.1]hept-7-yl)-[1-(2-chloro-benzenesulfonyl)-piperidin-3-yl]-methanone was prepared from (3S)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A2) and 7-aza-bicyclo[2.2.1]heptane hydrochloride (Tyger Scientific Inc., Ewing, N.J.) using the procedure described for the preparation of Example 1. White solid. Yield: 76%. Mass spectrum (ES) MH+=383.
(3S)-[1-(2-Chloro-benzenesulfonyl)-piperidin-3-yl]-(octahydro-quinolin-2-yl)-methanone was prepared from (3S)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A2) and decahydroisoquinoline using the procedure described for the preparation of Example 1. White solid. Yield: 84%. Mass spectrum (ES) MH+=425.
(3S)-(4aR,8aS)-rel-[1-(2-Chloro-benzenesulfonyl)-piperidin-3-yl]-(octahydro-quinolin-2-yl)-methanone was prepared from (3S)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A2) and racemic-trans-decahydroisoquinoline (TCI America, Portland, Oreg.) using the procedure described for the preparation of Example 1. White solid. Yield: 90%. Mass spectrum (ES) MH+=425.
(rac)-[1-(2-Chloro-benzenesulfonyl)-piperidin-3-yl]-morpholin-4-yl-methanone was prepared from (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A2) and morpholine using the procedure described for the preparation of Example 1. White foam. Yield: 56%. Mass spectrum (ES) MH+=373.
(3S)-([1-(2-Chloro-benzenesulfonyl)-piperidin-3-yl]-[(cis)-1,3,3a,4,7,7a-hexahydro-isoindol-2-yl]-methanone was prepared from (3S)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A2) and cis-2,3,3a,4,7,7a-hexahydro-1H-isoindole (prepared by the procedure described in R. D. Otzenberger et al. J. Org. Chem. 1974, 39, 319) using the procedure described for the preparation of Example 1. Pale yellow semi-solid. Yield: 41%. Mass spectrum (ES) MH+=409.
(3S)-1-(2-Chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (2-methyl-cyclopentyl)-amide was prepared from (3S)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A2) and 2-methyl-cyclopentylamine hydrochloride (of Intermediate B1) using the procedure described for the preparation of Example 1. Pale white solid. Yield: 35%. Mass spectrum (ES) MH+=385.
General Procedure
Step 1: Loading of Amine onto FMPB Resin
FMPB resin (Calbiochem-NovaBiochem Corp., San Diego, Calif.; 4-(4-formyl-3-methoxyphenoxy)butyryl AM resin, 50-100 mesh, loading 0.98 mmol/g) was loaded into the IRORI MiniKans (Discovery Partners International, San Diego, Calif.; 85 mg of resin per can). MiniKans to react with the same amine were combined together in one reaction vessel and suspended in a mixture of 1,2-dichloroethane, sodium triacetoxyborohydride (7 eq.), and the appropriate amine (7 eq.) and allowed to react overnight at room temperature. After the reaction solution was drained from each reaction vessel, MiniKans were washed twice with methanol and once with 10% (v/v) triethylamine/dichloromethane. At this stage all MiniKans from different reaction vessels (i.e. reacted with different amines) were combined together and washed sequentially with DMF (once), methanol (once), and dichloromethane (once), and then with DMF (twice), methanol (twice), and dichloromethane (twice). The MiniKans were dried under vacuum overnight.
Step 2: Coupling of Resin-Bound Amine with Fmoc-Nipecotic Acid
The MiniKans from the previous step were suspended in a 50/50 mixture of dichoromethane and DMF, and then N-Fmoc nipecotic acid (Chem-Impex International, Inc., Wood Dale, Ill.; 7 eq.), bromotris(pyrrolydino)phophonium hexafluorophosphate (PyBroP; Calbiochem-NovaBiochem Corp., San Diego, Calif.; 7 eq.) or O-Benzotriazole-N,N,N′,N′-tetramethyl-uronium-hexafluoro-phosphate (HBTU; Alfa Aesar, Ward Hill, Mass.; 7 eq.), and diisopropylethylamine (7 eq.) were added. The reaction was carried out at room temperature overnight. After the reaction solution was drained from the reaction vessel, MiniKans were washed and dried as described above.
Step 3: Capping Procedure
The MiniKans were suspended in DMF solution of acetic anhydride (3 eq.) and diisopropylethylamine (6 eq.) and allowed to react for 2 hours at room temperature. After 2 hours the capping solution was drained and MiniKans were washed and dried as described above.
Step 4: Removal of Fmoc Protective Group
The MiniKans were suspended in 20% (v/v) piperidine/DMF solution and allowed to react for 2 hours at room temperature. After 2 hours the reaction solution was drained and MiniKans were washed and dried as described above.
Step 5: Sulfonylation
The MiniKans were sorted on the IRORI sorter for the sulfonylation reaction. MiniKans to react with the same sulfonyl chloride were combined together in one reaction vessel and suspended in dichloromethane. Then the appropriate sulfonyl chloride (7 eq.) and diisopropylethylamine (7 eq.) were added and the reaction was allowed to go overnight at room temperature. After the reaction solution was drained from each reaction vessel, MiniKans were washed with dichloromethane in each individual reaction vessel. At this stage all MiniKans from different reaction vessels (i.e. reacted with different sulfonyl chlorides) were combined together and washed as described above. The MiniKans were then dried under vacuum overnight.
Step 6: Cleavage of Product from Solid Support
The MiniKans were sorted on the IRORI sorter for cleavage. The final products were cleaved from the solid support on the IRORI cleavage station as follows: TFA/dichloromethane (50/50, v/v; 3 mL) was added to each well. After 3 hours the solution was drained and collected, and each well containing a MiniKan was rinsed with dichloromethane (3 mL) for 20 minutes. The rinse was combined with the solution from the cleavage step and the combined solution was evaporated to dryness on the Genevac. The products were analyzed by LC-MS. Compounds with purity less than 85% were purified as follows:
Description of HT Purification
Samples were dissolved in mixtures of Methanol, ACN and DMSO and purified using the following instruments: Sciex 150 EX Mass Spec, Gilson 215 collector, Shimadzu prep HPLC system, Leap autoinjector. All compounds were purified using TFA buffers LC/MS in the positive ion detection: Solvent (A) 0.05% TFA/H20 (B) 0.035% TFA/ACN, using the appropriate linear gradient mode in 10 minutes, with a C-18 column, 2.0×10 cm eluting at 20 ml/min and mass directed collection
The following compounds were prepared by solid phase synthesis, using the amines and sulfonyl chlorides indicated:
3,5,7-Trimethyl-1-adamantanamine (which can be prepared by the procedure described in J. G. Henkel and J. T. Hane J. Med Chem. 1982, 25, 51-56) (approx. 1.0 equiv) is added to a solution of (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A1; approx. 0.8 equiv), 1-hydroxybenzotriazole hydrate (1.1 equiv), N,N-dimethylaminopyridine (approx. 1.7 equiv), and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (approx. 1.1 equiv) in dichloromethane (approx. 10 mL per equivalent). The solution is stirred for 24 h, and then diluted with dichloromethane, washed with 1 M HCl and then brine, dried (magnesium sulfate), filtered and evaporated. The crude product is purified by column chromatography, eluting with ethyl acetate/hexanes to give (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (3,5,7-trimethyl-adamantan-1-yl)-amide.
Amino-1-adamantanol (Aldrich Chemical Company, Inc., Milwaukee, Wisc.) (approx. 1.0 equiv) is added to a solution of (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (of Intermediate A1; approx. 0.8 equiv), 1-hydroxybenzotriazole hydrate (1.1 equiv), N,N-dimethylaminopyridine (approx. 1.7 equiv), and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (approx. 1.1 equiv) in dichloromethane (approx. 10 mL per equivalent). The solution is stirred for 24 h, and then diluted with dichloromethane, washed with 1 M HCl and then brine, dried (magnesium sulfate), filtered and evaporated. The crude product is purified by column chromatography, eluting with ethyl acetate/hexanes to give (rac)-1-(2-chloro-benzenesulfonyl)-piperidine-3-carboxylic acid (3-hydroxy-adamantan-1-yl)-amide.
The in vitro inhibition of 11β-HSD1 by compounds of the present invention were demonstrated by means of the following test:
Purified human HSD1 was diluted in 50 mM Tris-HCl, 100 mM NaCl, 0.1 mg/ml BSA, 0.02% Lubrol, 20 mM MgCl2, 10 mM glucose 6-phosphate, 0.4 mM NADPH, 60 U/ml glucose 6-phosphate dehydrogenase to a concentration of 1.5 ug/ml (Enzyme Solution). Cortisone (100 uM) in DMSO was diluted to 1 uM with 50 mM Tris-HCl, 100 mM NaCl (Substrate Solution). Testing compounds (40 uM) in DMSO was diluted 3 fold in series in DMSO and further diluted 20 fold in Substrate Solution. Enzyme Solution (10 ul/well) was added into 384 well microtiter plates followed by diluted compound solutions (10 ul/well) and mixed well. Samples were then incubated at 370 C for 30 min. EDTA/biotin-cortisol solution (10 ul/well) in 28 mM EDTA, 100 nM biotin-cortisol, 50 mM Tris-HCl, 100 mM NaCl was then added followed by 5 ul/well of anti-cortisol antibody (3.2 ug/ml) in 50 mM Tris-HCl, 100 mM NaCl, 0.1 mg/ml BSA and the solution was incubated at 37 degrees for 30 min. Five ul per well of Eu-conjugated anti-mouse IgG (16 nM) and APC-conjugated streptavidin (160 nM) in 50 mM Tris-HCl, 100 mM NaCl, 0.1 mg/ml BSA was added and the solution was incubated at room temperature for 2 hours. Signals were quantitated by reading time-resolved fluorescence on a Victor 5 reader (Wallac).
Percent inhibition of HSD1 activity by an agent at various concentrations was calculated by the formula % Inhibition=100*[1−(Fs−Fb)/(Ft−Fb)], where:
The inhibitory activities of test compounds were determined by the IC50s, or the concentration of compound that gave 50% inhibition.
The results of the in vitro inhibition of 11β-HSD1 by representative compounds of the present invention are shown in the following Table:
The in vivo inhibition of 11β-HSD1 by compounds of the present invention can be demonstrated by means of the following test:
The compound of the invention is formulated in 7.5% Modified Gelatin in water and is administered IP at 100 mg/kg to mice (male C57B1/6J, age ˜97 Days). After 30 minutes, cortisone formulated in gelatin is administered by s.c. injection at 1 mg/kg. After a further 40 minutes, blood samples are taken from the mice and are analyzed using LC-MS for the concentrations of cortisone, cortisol, and drug.
Percent inhibition of HSD1 activity by the inhibitor is calculated by the following formula:
% Inhibition=100*[1−(Cinh/Cveh)]
where:
It is to be understood that the invention is not limited to the particular embodiments of the invention described above, as variations of the particular embodiments may be made and still fall within the scope of the appended claims.
This application claims the benefit of U.S. Provisional Application No. 60/658,276, filed Mar. 3, 2005, which is hereby incorporated by reference in its entirety.
Number | Date | Country | |
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60658276 | Mar 2005 | US |