Claims
- 1. A method of inhibiting mammalian leukotriene biosynthesis or action which comprises administering a composition containing a pharmaceutical carrier and an effective amount of a compound of Formula I: ##STR87## wherein: X is Se, S, SO, SO.sub.2 or O;
- R.sup.1 is H; C.sub.1 to C.sub.6 alkyl; C.sub. to C.sub.6 acyl; lower acyloxy-lower alkyl; lower alkoxy-lower alkyl ##STR88## wherein substituted phenyl is as defined in the definition of R.sub.16 ; carbamoyl; ##STR89## SO.sub.2 -C.sub.6 H.sub.4 -p-CH.sub.3 ; SO.sub.2 CH.sub.3 ; an acyl group such that R.sup.1 -OH is an essential amino acid; benzyl; phenethyl; (CH.sub.2).sub.n OR.sup.a wherein R.sup.a is C.sub.1 to C.sub.6 alkyl or phenyl and n is 1 to 5; (CH.sub.2).sub.n COOR.sup.6 wherein n is 0 to 2; or lower acyloxy-lower alkoxy carbonyl;
- R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are independently selected hydrogen,
- (1) hydrogen;
- (2) alkyl having 1 to 6 carbon atoms;
- (3) alkenyl having 2 to 6 carbon atoms; and
- (4) --(CH.sub.2).sub.n M
- wherein n is 0 to 6 and M is
- (a) --OR.sup.16 ;
- (b) halogen;
- (c) --CF.sub.3 ;
- (d) --SR.sup.16 ;
- (e) phenyl or substituted phenyl wherein substituted phenyl is as defined in the definition of R.sup.16 ;
- (f) COOR.sup.6 ;
- (g) ##STR90## (h) tetrazole; (i) ##STR91## (j) --NR.sup.8 R.sup.9 ; (k) --NHSO.sub.2 R.sup.10 wherein R.sup.10 is OH, C.sub.1 to C.sub.6 alkyl, C.sub.1 or C.sub.6 alkoxy, or phenyl;
- (l) ##STR92## (m) --SOR.sup.11 wherein R.sup.11 is C.sub.1 to C.sub.6 alkyl; phenyl; substituted phenyl wherein substituted phenyl is as defined in the definition of R.sup.16 ; (CH.sub.2).sub.m COOR.sup.6 wherein m is 1 to 6, CN;formyl; or perfluoro-C.sub.1 to C.sub.4 alkyl; --CONR.sup.8 R.sup.9 ;
- (n) --CONR.sup.8 R.sup.9 ;
- (o) --SO.sub.2 NR.sup.8 R.sup.9 ;
- (p) --SO.sub.2 R.sup.13 wherein R.sup.13 is OH; C.sub.1 to C.sub.6 alkyl; H; phenyl; substituted phenyl wherein substituted phenyl is as defined in the definition of R.sup.16 ; (CH.sub.2).sub.m COOR.sup.6 wherein m is 1 to 6; CN; formyl; or perfluoro-C.sub.1 to C.sub.4 alkyl;
- (q) --NO.sub.2 ;
- (r) ##STR93## (s) ##STR94## (t) --CN; each R.sup.6 is independently H, phenyl or C.sub.1 to C.sub.6 alkyl;
- each R.sup.7 is independently C.sub.1 to C.sub.6 alkyl, benzyl, phenyl or C.sub.1 to C.sub.6 acyloxy-C.sub.1 to C.sub.6 alkyl;
- each R.sup.8 and each R.sup.9 is independently H, C.sub.1 to C.sub.4 acyl, phenyl, or substituted phenyl wherein the substituted phenyl is as defined in the definition of R.sub.16, or an R.sup.8 and an R.sup.9 may be joined through the N to which they are attached to form a heterocycloalkyl group of 5 to 8 ring atoms;
- each R.sup.14 is independently H, (CH.sub.2).sub.n COOR.sup.6 wherein n is 0 to 4, C.sub.1 to C.sub.6 alkyl; C.sub.1 to C.sub.6 alkoxy; C.sub.1 to C.sub.6 acyloxy-C.sub.1 to C.sub.6 alkoxy; phenyl; substituted phenyl wherein the substituted phenyl is as defined in the definition of R.sup.16 ; or C.sub.1 to C.sub.6 aminoalkyl such that R.sup.14 COOH is an essential amino acid;
- each R.sup.16 is indepentently H; lower alkoxy-lower alkyl; C.sub.1 to C.sub.6 alkyl; benzyl; lower acyloxy-lower alkyl; phenyl; substituted phenyl wherein the substituents are selected from C.sub.1 to C.sub.3 alkyl, halogen, CN, CF.sub.3, COOR.sup.6, CH.sub.2 COOR.sup.6, (CH.sub.2).sub.n NR.sup.8 R.sup.9 wherein n is 0 to 2, C.sub.1 to C.sub.3 alkoxy, or OH; --(CH.sub.2).sub.m COOR.sup.6, wherein m is 0 to 6; CN; formyl; perfluoroallkyl; or CH.sub.2 --R.sup.12 wherein R.sup.12 is C.sub.1 to C.sub.5 alkyldimethylamino or phenyl;
- and T is hydrogen or --OR.sup.15, where R.sup.15 is hydrogen, C.sub. to C.sub.6 alkyl, C.sub.1 to C.sub.6 alkylacyl, phenylacyl, or substituted phenyl-acyl wherein substituted phenyl is as defined in the definition of R.sup.16 or arylsulfonyl;
- and pharmaceutically acceptable salts thereof.
Mouse Macrophase Assay
This is a division of application Ser. No. 654,991 filed 9-26-84, now U.S. Pat. No. 4,666,907, which in turn is a continuation-in-part of U.S. Ser. No. 539,342, filed Oct. 5, 1983, now abandoned.
Phenothiazine derivatives and analogs thereof are useful as inhibitors of the biosynthesis of mammalian leukotrienes. As such, these compounds are useful therapeutic agents for treating allergic conditions, asthma, cardiovascular disorders, inflammation and certain skin diseases.
The leukotrienes are a novel group of biologically active substances derived from arachidonic acid through the action of the 5-lipoxygenase enzyme system. There are two groups of leukotrienes derived from a common unstable precursor Leukotriene A.sub.4. The first of these are the peptido-lipid leukotrienes, the most important being Leukotrienes C.sub.4 and D.sub.4. These compounds collectively account for the biologically active material known as the slow reacting substance of anaphylaxis.
The leukotrienes are potent smooth muscle contracting agents, particularly on respiratory smooth muscle but also on other tissues (e.g., gall bladder). In addition, they promote mucous production, modulate vascular permeability changes and are potent inflammatory agents in human skin. The most important compound in the second group of leukotrienes is Leukotriene B.sub.4, a dihydroxy fatty acid. This compound is a potent chemotactic agent for neutrophils and eosinophils. It also effects other cell types such as lymphocytes and for example may modulate the action of T-suppressor cells and natural killer cells. When injected in vivo, in addition to promoting the accumulation of leukocytes, Leukotriene B.sub.4 is also a potent hyperalgesic agent and can modulate vascular permeability changes through a neutrophil dependent mechanism. See: D. M. Bailey and F. B. Casey, Ann. Rpts. Med. Chem. 17, 203 (1982).
As indicated above, the leukotrienes have been implicated in numerous disease states. Inhibition of leukotriene biosynthesis and/or antagonism of leukotriene action, will therefore provide a therapeutic benefit to patients suffering from leukotriene mediated disease states. These disease states include, but are not limited to; asthma; allergic conditions such as allergic rhinitis; skin diseases including psoriasis and atopic dermatitis; inflammation; gouty arthritis; gall bladder spasms; and cardiovascular disorders such as angina.
Phenothiazine derivatives of the general Formula II are known compounds: ##STR2## See for example; "Progress in Drug Research", Volume 5, E. Tucker, ed., Birkhauser Verlag, Basel Switzerland (1963) pages 274-383; V. A. Rigas et al., Prostaglandins Med. 183 (1981); J. M. Perel et al., Neurotoxicoloqy, Raven Press, New York, 1977, pp. 9-13; V. Fishman et al., J. Pharm. Exp. Ther. 150 165 (1965); Arch. Intern. Pharm. Ther. 74 314 (1947); N. Bhargava et al., Gazz. Chim. Ital. 109 201 (1979); V. F. Garry et al., Biochem. Pharm. 21 2801 (1972); S. C. Mitchell et al., Drug Met. Disp. 7 399 (1979); T. Akera et al., Biochem. Pharm. 27 995 (1978); I. Creese et al., Europ. J. Pharm., 47 291 (1978); S. C. Mitchell, Drug Met. Rev., 13 319 (1982); T. Ellison et al., Am. J. Vet. Res. (7) 519 (1957); K. P. Singh et al., Asian Med. J. 19 296 (1976) and H. B. Collier, Can. J. Med. Sci. 31 195 (1953).
Several derivatives of phenothiazine are known to be inhibitors of enzymes, including the 15-lipoxygenase enzyme isolated from soybeans. However, none of the compounds of Formula A are taught to have leukotriene biosynthesis inhibiting ability via the inhibition of the mammalian 5-lipoxygenase enzyme system.
It has been discovered that compounds of the Formula A type and analogs thereof are effective inhibitors of mammalian leukotriene biosynthesis and are thus useful in the treatment of conditions such as asthma, allergies, inflammation, psoriasis, and the like in mammals, especially in humans.
Compounds of the Formula A type and analogs thereof may also be used to treat or prevent mammalian (especially, human) disease states such as erosive gastritis; erosive esophagitis; inflammatory bowel disease; ethanol-induced hemorrhagic erosions; hepatic ischemia; noxious agent induced damage or necrosis of hepatic, pancreatic, renal, or myocardial tissue; liver parenchymal damage caused by hepatoxic agents such as CCl.sub.4 and D-galactosamine; ischemic renal failure; disease-induced hepatic damage; bile salt induced pancreatic or gastric damage; trauma- or stress-induced cell damage; and glycerol-induced renal failure.
The present invention relates to pharmaceutical compositions containing a compound of the general Formula I and a pharmaceutically acceptable carrier; a method of treatment using compounds of Formula I; and certain novel compounds of Formula I: ##STR3## wherein: X is Se, S, SO, SO.sub.2 or O; R.sup.1 is H; C.sub.1 to C.sub.6 alkyl; C.sub.1 to C.sub.6 acyl; lower acyloxylower alkyl (e.g. --CH(CH.sub.3)OCOC(CH.sub.3).sub.3); lower alkoxy-lower alkyl (e.g. --CH(CH.sub.3)OC.sub.2 H.sub.5); ##STR4## wherein substituted phenyl is as defined in the definition of R.sup.16 ; carbamoyl; ##STR5## SO.sub.2 -C.sub.6 H.sub.4 -p-CH.sub.3 ; SO.sub.2 CH.sub.3 ; an acyl group such that R.sup.1 -OH is an essential amino acid; benzyl; phenethyl; (CH.sub.2).sub.n OR.sup.a wherein R.sup.a is C.sub.1 to C.sub.6 alkyl or phenyl and n is 1 to 5; (CH.sub.2).sub.n COOR.sup.6 wherein n is 0 to 2; or lower acyloxy-lower alkoxy carbonyl (e.g. --COOCH(O.sub.2 CCH.sub.3)CH.sub.3); R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are independently selected from:
The numbers surrounding Formula I designate the substituent positions, and R.sup.2, R.sup.3, R.sup.4, R.sup.5 and T may be positioned anywhere in the structure except at position 10.
The term alkyl, unless otherwise indicated, includes straight chain, branched chain and cycloalkyl groups of the number of carbon atoms shown. The term halogen, unless otherwise indicated, includes Cl, Br, I and F.
The term lower as applied to the terms alkyl, acyl, alkoxy, acyloxy, and the like, means a group having 1 to 6 carbon atoms and preferably 1 to 4 carbon atoms. The term phenylacyl means a group having the formula ##STR11##
The term aryl includes cyclic structures having the requisite degree of unsaturation to show a characteristic "aromatic" downfield proton NMR spectrum. Examples include phenyl, substituted phenyl (as defined above in the definition of R.sup.16) naphthyl, anthracenyl, and the like, and include heteroaryl species containing one or more of the heteroatoms selected from O, N or S.
The term essential amino acid is employed to include the following amino acids; lysine, tryptophan, histidine, phenylalanine, leucine, isoleucine, threonine, methionine, valine, arginine, alanine, proline, glycine, serine, cysteine, tyrosine, asparagine, glutamine, aspartic acid and glutamic acid.
In those instances when asymmetric centers are present, more than one stereoisomer is possible, and all possible isomeric forms are deemed to be included within the planar structural representations shown. Optically active (R) and (S) isomers may be resolved using conventional techniques known to the skilled artisan.
A preferred composition is comprised of compounds of the Formula I wherein:
More preferred compounds for use in the compositions of the present invention are those of the Formula I wherein:
Most preferred compounds for use in the compositions of the present invention are compounds of the Formula I wherein:
C.sub.1 to C.sub.6 alkyl;
Another preferred group of compounds for use in the compositions of the present invention are compounds of the Formula I wherein:
Another particularly preferred group of compounds for use in the compositions of the present invention are compounds of Formula III: ##STR31## wherein: R.sup.1 is H, C.sub.1 to C.sub.4 acyl, lower acyloxy-lower alkyl, or lower acyloxy-lower alkoxycarbonyl;
Examples of the Formula I compounds useful in the present compositions are tabulated below. In Table I, the number preceding the R.sup.2 -R.sup.5 and T definitions signifies that groups position on the ring system. Standard abbreviations are used, for example, Ph for phenyl, Bz for benzoyl, Ts for p-toluenesulfonyl, Me for methyl, Bu for butyl, Et for ethyl and Ac for acetyl.
The compounds of the Formula I have unexpected activity as inhibitors of the mammalian biosynthesis of both leukotrien B.sub.4, as well as leukotrienes C.sub.4, D.sub.4, E.sub.4 and F.sub.4, the active elements of slow reacting substance of anaphylaxis (SRS-A). This inhibition of the biosynthesis of leukotrienes indicates that the compositions would be useful to treat, prevent or ameliorate, in mammals and especially in humans (1) pulmonary conditions including diseases such as asthma, (2) allergies and allergic reactions such as allergic rhinitis, contact dermatitis, allergic conjunctivitis and the like (3) inflammation such as arthritis, (4) pain, (5) skin conditions such as psoriasis and the like and (5) cardiovascular conditions such as angina and the like.
Representative compounds of Formula I have been tested using one or more of the following assays to determine their mammalian leukotriene biosynthesis inhibiting activity and other relevant activities.
Mouse peritoneal macrophages were treated sequentially with arachidonic acid (labelled with tritium); the compound being evaluated as an inhibitor, and a stimulator (zymosan). Metabolites derived from arachidonic acid (PGE.sub.2, 6-Keto PG-F.sub.1@ and Leukotriene C.sub.4) were separated from the incubation medium by extraction and chromatography, and then quantitated by determining the amount of radioactivity (cpm) associated with each of them. Inhibitors caused a reduction in the amount of radioactivity (cpm) associated with a given metabolite. (This protocol is identical to that described in the reference except that the radioactivity herein associated with the LTC.sub.4 was determined by counting an aliquot of the final aqueous solution directly rather than chromatographing it first).
Reference: Humes J.L. et al.. J. Biol. Chem. 257. 1591-4 (1982).
Male guinea pigs weighing 300-350 g were sensitized by injecting (i.p.) 0.5 ml of a suspension containing 0.4 mg of egg albumin (Ovalbumin, Grade V, Sigma Chemical Co.) and 4.0 g aluminum hydroxide in 19.6 ml of saline. Two weeks were permitted for sensitization to occur.
Three sensitized guinea pigs were stunned and exsanguinated. The tracheas were removed, freed of adhering tissue and divided longitudinally by cutting through the cartilaginous tissue directly opposite the muscle insertion. Each opened trachea was then transected between every second cartilage. Four of the cut sections were tied together, end to end in a series with No. 0.7 silk thread ensuring that the tracheal muscles were all in the same vertical plane. Thus, each chain consisted of tissue from three different animals.
The chain so formed was then suspended under 1 g of tension (by silk ties at each end) in a 20 ml organ bath containing 10 ml of modified.sup.1 Krebs-Henseleit buffer solution gassed with 95% O.sub.2 and 5% CO.sub.2 at 37.degree. C. Mepyramine (0.55 .mu.g/ml) and indomethacin (2.67 .mu.g/ml were added to the buffer to avoid the contribution of histamine receptors and cyclooxygenase products to the contraction. To record responses one end of the tracheal chain was attached to a Gould Statham UC-2 force displacement transducer which was connected to a Beckman Type R-dynograph. The preparations were allowed to equilibrate for one hour during which time the tissues were automatically washed (10 ml volume displacement) every 6 minutes.
After the equilibration period the tissues primed with methacholine (3 .mu.g/lml; 1.5.times.10.sup.-5 M), washed and allowed to recover to baseline. The tissues were treated again with a second dose of methacholine, washed, allowed to return to baseline and washed for an additional hour.
Two chains were used as a control. These were incubated in a concentration of egg albumin sufficient to induce an average contraction of 50-80% of the methacholine response.
Each compound to be tested was added to two other baths (at a final concentration in each bath of 10 .mu.g/ml or lower) 15 minutes prior to challenging the fresh chains with egg albumin.
The response of the challenged tissue was expressed as a percentage of the methacholine maximum. The % inhibition for each compound was then calculated. Compounds which at 10 .mu.g/ml (final concentration) inhibited the egg albumin response by 50% or more were retested at a lower concentration.
Rats under ether anesthesia are injected (i.p.) with 8 ml of a suspension of sodium caseinate (6 grams in ca. 50 ml water). After 15-24 hours the rats are sacrificed (CO.sub.2) and the cells from the peritoneal cavity are recovered by lavage with 20 ml of buffer (Eagles MEM containing 30 mM HEPES adjusted to pH 7.4 with NaOH). The cells are pelleted (350.times. g, 5 min.), resuspended in buffer with vigorous shaking, filtered through lens paper, recentrifuged and finally suspended in buffer at a concentration of 10 cells/ml. A 500 .mu.l aliquot of PMN suspension and test compound are preincubated for 2 minutes at 37.degree. C., followed by the addition of 10 .mu.M A-23187. The suspension is stirred for an additional 4 minutes then bioassayed for LTB.sub.4 content by adding an aliquot to a second 500 .mu.l portion of the PMN at 37.degree. C. The LTB.sub.4 produced in the first incubation causes aggregation of the second PMN, which is measured as a change in light transmission. The size of the assay aliquot is chosen to give a submaximal transmission change (usually -70%) for the untreated control. The percentage inhibition of LTB.sub.4 formation is calculated from the ratio of transmission change in the sample to the transmission change in the compound-free control.
Results from the assays described above for several compounds of Formula I are shown in Table II.
In addition to the assay results described in Table II, the following assays were employed to determine the effectiveness of selected compounds of Formula I as antiasthma and analgesia agents.
Rats were obtained from an inbred line of asthmatic rats. Both female and male rats from 200 to 300 g were used.
Egg albumin (EA), grade V, crystallized and lyophilized, was obtained from Sigma Chemical Co., St. Louis. Bordetella pertussis vaccine, containing 30.times.10.sup.9 killed bacteria per ml was obtained from the Institut Armand-Frappier, Laval des Rapides, Quebec. Aluminum hydroxide was obtained from the Regeis Chemical Company, Chicago.
The challenge and subsequent respiratory recordings were carried out in a clear plastic box with internal dimensions 10.times.6.times.4 inches. The top of the box was removable; in use, it was held firmly in place by four clamps and an airtight seal was maintained by a soft rubber gasket. Through the center of each end of the chamber a Devilbiss nebulizer (No. 40) was inserted via an airtight seal and each end of the box also had an outlet. A Fleisch No. 0000 pneumotachograph was inserted into one end of the box and coupled to a Grass volumetric pressure transducer (PT5-A) which was then connected to a Beckman Type R Dynograph through appropriate couplers. While aerosolizing the antigen, the outlets were open and the pneumotachograph was isolated from the chamber. The outlets were closed and the pneumotachograph and the chamber were connected during the recording or the respiratory patterns. For challenge, 2 ml of a 3% solution of antigen in saline was placed into each nebulizer and the aerosol was generated with air from a small potter diaphragm pump operating at 10 psi and a flow of 8 liters/minutes.
Rats were sensitized by injecting (s.c.) 1 ml of a suspension containing 1 mg EA and 200 mg aluminum hydroxide in saline. Simultaneously, they received a injection (i.p.) of 0.5 ml of B. pertussis vaccine. They were used between days 14 and 18 postsensitization. In order to eliminate the serotonin component of the response, rats were pretreated intravenously 5 minutes prior to aerosol challenge with 30 gm kg.sup.-1 methylserzide. Rats were then exposed to an aerosol of 3% EA in saline for exactly 1 minute, then their respiratory profiles were recorded for a further 25-30 minutes. The duration of continuous dyspnoea was measured from the respiratory recordings.
Compounds were generally administered either intraperitoneally 1 hour prior to challenge or orally 11/2 hours prior to challenge. They were either dissolved in dimethylsulfoxide or suspended in 0.1% methocel and 0.5% Tween 80. The volume injected has 2 ml kg-1 (intraperitoneally) or 10 ml kg-1 (orally). Prior to oral treatment rats were starved overnight. Their activity was determined in terms of their ability to decrease the duration of symptoms of dyspnoea in comparison with a group of vehicle-treated controls. Usually, a compound was evaluated at a series of doses and an ED.sub.50 was determined. This was defined as the dose (mg/kg) which would inhibit the duration of symptoms by 50%.
Female Sprague-Dawley rats, 35-40 g were fasted overnight. Platelet activating factor, PAF, (L-lecithin B-acetyl O-alkyl) 1 .mu.g/0.1 ml was given by subplantar injection in the rat paw. The compounds to be evaluated were homogenized in aqueous Vehicle (0.9% benzyl alcohol, 0.5% Tween 80 and 0.4% methylcellulose) and administered orally in a volume of 0.1 ml, 30 minutes prior to PAF.
Animals were tested 1, 2, 3 and 4 hours after PAF administration. The vocalization threshold, defined as the pressure (mm Hg) needed to evoke a squeak response, was recorded for both the injected and contralateral paw. No animal was subjected to pressure greater than 60 mm Hg. Hyperalgesia is defined as a decrease in vocalization threshold as compared to a normal paw. Percent inhibition of hyperalgesia was calculated as the proportion of animals with vocalization thresholds greater than 200% of controls.
Results for the assays described above for several compounds of Formula I are shown in Table III.
The cytoprotective activity of a compound may be observed in both animals and man by noting the increased resistance of the gastrointestinal mucosa to the noxious effects of strong irritants, for example, the ulcerogenic effects of aspirin or indomenthacin. In addition to lessening the effect of non-steroidal anit-inflammatory drugs on the gastrointestinal tract, animal studies show that cytoprotective compounds will prevent gastric lesions induced by oral administration of strong acids, strong bases, ethanol, hypertonic saline solutions and the like.
Two assays can be used to measure cytoprotective ability. These assays are; (A) an ethanol-induced gastric ulcer assay and (B) an indomethacin-induced ulcer assay.
Twenty-four hour fasted Sprague-Dawley (S.D.) rats are perorally (p.o.) dosed with 1.0 ml absolute ethanol. Fifteen to thirty minutes prior to ethanol administration, groups of rats each receive either an aqueous vehicle (aqueous methylcellulose 5% wt.) or the test compound at various doses perorally. One hour later, the animals are sacrificed and stomach mucosae are examined for resulting lesions.
Indomethacin, 10 mg/kg p.o., is used to induce ulcers in 24 hour fasted S.D. rats. Fifteen minutes prior to indomethacin administration, groups of rats each receive either an aqueous vehicle (5% by weight methylcellulose) or the test compound at various doses perorally. Four hours later the animals are sacrificed and stomach mucosae are examined for resulting ulcers.
The pharmaceutical compositions will contain a sufficient amount of a compound of Formula I in a dosage form suitable for inhibiting the mammalian biosynthesis of leukotrienes or, for the treatment desired. The effective concentration of a Formula I compound in the composition will vary as required by the nature and the severity of the condition to be treated, the particular compound selected, the mode of administration, the dosage form and the pharmacological effect and level desired.
Any suitable route of administration may be employed for providing a mammal, especially a human with an effective dosage of a leukotriene antagonist. For example, oral, rectal, transdermal, parenteral, intramuscular, intravenous and the like may be employed. Dosage forms include tablets, troches, dispersions, suspensions, solutions, capsules and the like.
A general daily dosage of a Formula I compound for anti-asthmatic, anti-allergic, anti-inflammatory and, generally, uses other than cytoprotection will range from about 10 .mu.g/kg to 20 mg/kg of body weight. A preferred daily dosage range is from 50 .mu.g/kg to 20 mg/kg and a most preferred dosage range is from 100 .mu.g/kg to 10 mg/kg.
The exact amount of a compound of the Formula I to be used as a cytoprotective agent will depend on, inter alia, whether it is being administered to heal damaged cells or to avoid future damage, on the nature of the damaged cells (e.g., gastro-intestinal ulcerations vs. nephrotic necrosis), and on the nature of the causative agent. An example of the use of a compound of the Formula I in avoiding future damage would be co-administration of a compound of the Formula I with a non-steroidal anti-inflammatory drug (for example, indomethacin) that might otherwise cause such damage. For such use, the compound of Formula I is administered from 30 minutes prior up to 30 minutes after administration of the NSAID. Preferably, it is administered prior to or simultaneously with the NSAID.
The effective daily dosage level for compounds of Formula I inducing cytoprotection in mammals, especially humans, will generally range from about 0.002 mg/kg to about 100 mg/kg, preferably from about 0.02 mg/kg to about 30 mg/kg. The dosage may be administered in single or divided individual doses.
The pharmaceutical compositions of the present invention comprise a compound of formula I as an active ingredient or a pharmaceutically acceptable salt thereof, and may also contain a pharmaceutically acceptable carrier and optionally other therapeutic ingredients. The term "pharmaceutically acceptable salts" refers to salts prepared from pharmaceutically acceptable non-toxic bases including inorganic bases and organic bases. Salts derived from inorganic bases include sodium, potassium, lithium, ammonium, calcium, magnesium, ferrous, zinc, copper, manganous, aluminum, ferric, manganic salts and the like. Particularly preferred are the ammonium, potassium, sodium, calcium and magnesium salts. Salts derived from pharmaceutically acceptable organic non-toxic bases include salts of primary, secondary, and tertiary amines, substituted amines including naturally occurring substituted amines, cyclic amines and basic ion exchange resins, such as isopropylamine, trimethylamine, diethylamine, triethylamine, tripropylamine, ethanolamine, 2-dimethylaminoethanol, 2-diethylaminoethanol, tromethamine, lysine, arginine, histidine, caffeine, procaine, hydrabamine, choline, betaine, ethylenediamine, glucosamine, methylglucamine, theobromine, purines, piperazine, piperidine, N-ethylpiperidine, N,N.sup.1 -dibenzylethylenediamine, morpholine, N-ethyl morpholine, polyamine resins and the like.
When the compound of Formula I is basic, salts may be prepared from pharmaceutically acceptable non-toxic acids, including inorganic and organic acids. Such acids include hydrochloric, hydrobromic, sulfuric, nitric, isethionic, methanesulfonic, ethanesulfonic, benzenesulfonic, p-toluenesulfonic, acetic, benzoic, camphorsulfonic, citric, fumaric, gluconic, glutamic, lactic, malic, maleic, mandelic, mucic, pamoic, pantothenic, phosphoric, succinic, tartaric acid and the like. Particularly preferred are hydrochloric, hydrobromic, citric, maleic, phosphoric, sulfuric and tartaric acids. For a helpful discussion of pharmaceutical salts see S. M. Berge et al., Journal of Pharmaceutical Sciences, 66, 1-19 (1977), the disclosure of which is hereby incorporated herein by reference.
The compositions include compositions suitable for oral, rectal, ophthalmic, pulmonary, nasal, dermal, topical or parenteral (including subcutaneous, intramuscular and intravenous) administration, although the most suitable route in any given case will depend on the nature and severity of the conditions being trated and on the nature of the active ingredient. They may be conveniently presented in unit dosage form and prepared by any of the methods well-known in the art of pharmacy.
For treating pulmonary conditions such as asthma, the mode of administration may be oral, parenteral, by inhalation, by suppository and the like. Suitable oral dosage forms are tablets, elixirs, emulsions, solutions, capsules, including delayed or sustained release capsules and the like. Parenteral dosage forms include solutions, emulsions and the like. Dosage forms for administration by inhalation including sprays, aerosols and the like. These inhalation formulations may be administered in metered doses ranging from about 0.1 .mu.g to about 200 .mu.g, administered as needed.
For treating allergies or allergic reactions, such as allergic conjunctivitis, allergic rhinitis and the like, the Formula I compound may be administered by any conventional mode, e.g. orally, parenterally, topically, subcutaneously, by inhalation and the like.
The oral and parenteral dosage forms are the same type as for the pulmonary treatment. The topical application dosage forms include ointments, salves, controlled release patches, emulsions, solutions, thixotropic formulations, powders, sprays and the like. For topical application, the percent by weight of the active ingredient (Formula I compound) may vary from about 0.001 to about 10%.
For treating inflammation the mode of administration may be oral, parenteral, by suppository and the like. The various dosage forms are the same as those described above.
For treating skin diseases such as psoriasis, atopic dermatitis and the like, oral, topical or parenteral administration is useful. For topical application to the diseased area salves, patches, controlled release patches, emulsions, etc., are convenient dosage forms.
For use as an analgesic, i.e. for treating pain, any suitable mode of administration may be used, e.g., oral, parenteral, by insufflation, by suppository and the like.
For treating cardiovascular conditions such as angina pectoris, etc., any suitable mode of administration, e.g. oral, parenteral, topical, insufflation, etc. and dosage form e.g. pills, liquid formulations, controlled release capsules, controlled release skin patches, etc. may be used.
In addition to the common dosage forms set out above, the compound of Formula I may also be administered for the various utilities and indications or for inhibiting leukotriene synthesis by controlled release means and/or delivery devices such as those described in U.S. Pat. Nos. 3,845,770; 3,916,899; 3,536,809; 3,598,123; 3,630,200 and 4,008,719. Dosage forms for application to treat the eye are also disclosed in U.S. 4,348,398. These disclosures are hereby incorporated herein by reference
For use where a composition for intravenous administration is employed, a suitable dosage range for anti-asthmatic, anti-inflammatory or anti-allergic use is from about 0.01 mg to about 20 mg (preferably from about 0.1 mg to about 10 mg) of a compound of formula I per kg of body weight per day and for cytoprotective use from about 0.002 mg to about 100 mg (preferably from about 0.02 mg to about 30 mg and more preferably from about 0.1 mg to about 10 mg) of a compound of Formula I per kg of body weight per day. In the case where an oral composition is employed, a suitable dosage range for anti-asthmatic, anti-inflammatory or anti-allergic use is, e.g. from about 1 to about 100 of a compound of formula I per kg of body weight per day, preferably from about 5 mg to about 40 mg per kg and for cytoprotective use from about 0.01 mg to about 100 mg (preferably from about 0.1 mg to about 30 mg and more preferably from about 0.1 mg to about 10 mg) of a compound of Formula I per kg of body weight per day.
For administration by inhalation, the compounds of the present invention are conveniently delivered in the form of an aerosol spray presentation from pressurized packs or a nebuliser. The preferred composition for inhalation is a powder which may be formulated as a cartridge from which the powder composition may be inhaled with the aid of a suitable device. In the case of a pressurized aerosol, the dosage unit may be determined by providing a valve to deliver a metered amount.
In practical use, leukotriene inhibitors of Formula I can be combined as the active ingredient in intimate admixture with a pharmaceutical carrier according to conventional pharmaceutical compounding techniques. The carrier may take a wide variety of forms depending on the form of preparation desired for administration, e.g., oral or intravenous. In preparing the compositions for oral dosage form, any of the usual pharmaceutical media may be employed, such as, for example, water glycols, oils, alcohols, flavoring agents, preservatives, coloring agents and the like in the case of oral liquid preparations, such as, for example, suspensions, elixirs and solutions; or carriers such as starches, sugars, diluents, granulating agents, lubricants, binders, disintegrating agents and the like in the case of oral solid preparations such as, for example, powders, capsules and tablets. Because of their ease of administration, tablets and capsules represent the most advantageous oral dosage unit form, in which case solid pharmaceutical carriers are obviously employed. If desired, tablets may be sugar coated or enteric coated by standard techniques.
Pharmaceutical compositions of the present invention suitable for oral administration and by inhalation in the case of asthma therapy may be presented as discrete units such as capsules, cachets or tablets each containing a predetermined amount of the active ingredient, as a powder or granules or as a solution or a suspension in an aqueous liquid, a non-aqueous liquid, an oil-in-water emulsion or a water-in-oil liquid emulsion. Such compositions may be prepared by any of the methods of pharmacy but all methods include the step of bringing into association the active ingredient with the carrier which constitutes one or more necessary ingredients. In general, the compositions are prepared by uniformly and intimately admixing the active ingredient with liquid carriers or finely divided solid carriers or both, and then, if necessary, shaping the product into the desired presentation. For example, a tablet may be prepared by compression or molding, optionally with one or more accessory ingredients. Compressed tablets may be prepared by compressing in a suitable machine, the active ingredient in a free-flowing form such as powder or granules, optionally mixed with a binder, lubricant, inert diluent, lubricating, surface active or dispersing agent. Molded tablets may be made by molding in a suitable machine, a mixture of the powdered compound moistened with an inert liquid diluent. Desirably, each tablet contains from about 25 mg to about 500 mg of the active ingredient and each cachet or capsule contains from about 25 to about 500 mg of the active ingredient.
The following are examples of representative pharmaceutical dosage forms for the leukotriene inhibitors of Formula I:______________________________________Injectable Suspension mg/ml______________________________________Compound of Formula I 2Methylcellulose 5.0Tween 80 0.5Benzyl alcohol 9.0Methyl paraben 1.8Propyl paraben 0.2Water for injection to a total volume of 1 ml______________________________________Tablet mg/tablet______________________________________Compound of Formula I 25.0Microcrystalline Cellulose 325.0Providone 14.0Microcrystalline Cellulose 90.0Pregelatinized Starch 43.5Magnesium Stearate 2.5 500______________________________________Capsule mg/capsule______________________________________Compound of Formula I 25Lactose Powder 573.5Magnesium Stearate 1.5 600______________________________________
In addition to the compounds of Formula I, the pharmaceutical compositions of the present invention can also contain other active ingredients, such as cyclooxygenase inhibitors, non-steroidal anti-inflammatory drugs (NSAIDs), peripheral analgesic agents such as zomepirac diflunisal and the like. The weight ratio of the compound of the Formula I to the second active ingredient may be varied and will depend upon the effective dose of each ingredient. Generally, an effective dose of each will be used. Thus, for example, when a compound of the Formula I is combined with an NSAID the weight ratio of the compound of the Formula I to the NSAID will generally range from about 1000:1 to about 1:1000, preferably about 200:1 to about 1:200. Combinations of a compound of the Formula I and other active ingredients will generally also be within the aforementioned range, but in each case, an effective dose of each active ingredient should be used.
NSAIDs can be characterized into five groups:
The propionic acid derivatives which may be used comprise: ibuprofen, ibuprufen aluminum, indoprofen, ketoprofen, naproxen, benoxaprofen, flurbiprofen, fenoprofen, fenbufen, ketoprofen, indoprofen, pirprofen, carprofen, oxaprozin, pranoprofen, miroprofen, tioxaprofen, suprofen, almino-profen, tiaprofenic acid, fluprofen and bucloxic acid. Structurally related propionic acid derivatives having similar analgesic and anti-inflammatory properties are also intended to be included in this group.
Thus, "propionic acid derivatives" as defined herein are non-narcotic analgesics/non-steroidal anti-inflammatory drugs having a free --CH(CH.sub.3)COOH or --CH.sub.2 CH.sub.2 COOH group (which optionally can be in the form of a pharmaceutically acceptable salt group, e.g., --CH(CH.sub.3)COO.sup.- Na.sup.+ or --CH.sub.2 CH.sub.2 COO.sup.- NA.sup.+), typically attached directly or via a carbonyl function to a ring system, preferably to an aromatic ring system.
The acetic acid derivatives which may be used comprise: indomethacin, which is a preferred NSAID, sulindac, tolmetin, zomepirac, diclofenac, fenclofenac, alclofenac, ibufenac, isoxepac, furofenac, tiopinac, zidometacin, acemetacin, fentiazac, clidanac, oxpinac, and fenclozic acid. Structurally related acetic acid derivatives having similar analgesic and anti-inflammatory properties are also intended to be encompassed by this group.
Thus, "acetic acid derivatives" as defined herein are non-narcotic analgesics/non-steroidal anti-inflammatory drugs having a free --CH.sub.2 COOH group (which optionally can be in the form of a pharmaceutically acceptable salt group, e.g. --CH.sub.2 COO.sup.- Na.sup.+), typically attached directly to a ring system, preferably to an aromatic or heteroaromatic ring system.
The fenamic acid derivatives which may be used comprise: mefenamic acid, meclofenamic acid, flufenamic acid, niflumic acid and tolfenamic acid. Structurally related fenamic acid derivatives having similar analgesic and anti-inflammatory properties are also intended to be encompassed by this group.
Thus, "fenamic acid derivatives" as defined herein are non-narcotic analgesics/non-steroidal anti-inflammatory drugs which contain the basic structure: ##STR80## which can bear a variety of substituents and in which the free --COOH group can be in the form of a pharmaceutically acceptable salt group, e.g., --COO.sup.- Na.sup.+.
The biphenylcarboxylic acid derivatives which can be used comprise: diflunisal and flufenisal. Structurally related biphenylcarboxylic acid derivatives having similar analgesic and anti-inflammatory properties are also intended to be encompassed by this group.
Thus, "biphenylcarboxylic acid derivatives" as defined herein are non-narcotic analgesics/non-steroidal anti-inflammatory drugs which contain the basic structure: ##STR81## which can bear a variety of substituents and in which the free --COOH group can be in the form of a pharmaceutically acceptable salt group, e.g., --COO.sup.- Na.sup.+.
The oxicams which can be used in the present invention comprise: piroxicam, sudoxicam, isoxicam and 4-hydroxyl-1,2-benzothiazine 1,1-dioxide 4-(N-phenyl)-carboxamide. Structurally related oxicams having similar analgesic and anti-inflammatory properties are also intended to be encompassed by this group.
Thus, "oxicams" as defined herein are non-narcotic analgesics/non-steroidal anti-inflammatory drugs which have the general formula: ##STR82## wherein R is an aryl or heteroaryl ring system.
The following NSAIDs may also be used: acemetacin, alminoprofen, amfenac sodium, aminoprofen, anitrazafen, antrafenine, auranofin, bendazac lysinate, benzydamine, beprozin, broperamole, bufezolac, carprofen, cinmetacin, ciproquazone, clidanac, cloximate, dazidamine, deboxamet, delmetacin, detomidine, dexindoprofen, diacerein, di-fisalamine, difenpyramide, emorfazone, enfenamic acid, enolicam, epirizole, etersalate, etodolac, etofenamate, fanetizole mesylate, fenclofenac, fenclorac, fendosal, fenflumizole, fentiazac, feprazone, floctafenine, flunixin, flunoxaprofen, fluproquazone, fopirtoline, fosfosal, furcloprofen, furofenac, glucametacin, guaimesal, ibuproxam, isofezolac, isonixim, isoprofen, isoxepac, isoxicam, lefetamine HCl, leflunomide, lofemizole, lonazolac calcium, lotifazole, loxoprofen, lysin clonixinate, meclofenamate sodium, meseclazone, miroprofen, nabumetone, nictindole, nimesulide, orpanoxin, oxametacin, oxapadol, oxaprozin, perisoxal citrate, pimeprofen, pimetacin, piproxen, pirazolac, pirfenidone, pirprofen, pranoprofen, proglumetacin maleate, proquazone, pyridoxiprofen, sudoxicam, suprofen, talmetacin, talniflumate, tenoxicam, thiazolinobutazone, thielavin B, tiaprofenic acid, tiaramide HCl, tiflamizole, timegadine, tioxaprofen, tolfenamic acid, tolpadol, tryptamid, ufenamate, and zidometacin.
The following NSAIDs, designated by company code number, may also be used: 480156S, AA861, AD1491, AD1590, AFP802, AFP860, AHR6293, AI77B, AP504, AU8001, BAYo8276, BPPC, BW540C, BW755C, CHINOIN 127, CN100, CO893XX, CPP, D10242, DKA9, DV17, EB382, EGYT2829, EL508, F1044, FZ, GP53633, GP650, GV3658, HG/3, ITCl, ITF, ITF182, KB1043, KC8973, KCNTEI6090, KME4, LA2851, LT696, LU20884, M7074, MED15, MG18311, MR714, MR897, MY309, NO164, ONO3144, PR823, PV102, PV108, QZ16, R830, RS2131, RU16029, RU26559, RUB265, SCR152, SH440, SIR133, SIR136, SIR92, SPAS510, SQ27239, ST281, SX 1032, SY6001, SaH46798, TA60, TAI901, TEI615, TVX2706, TVX960, TZI615, U60257, UR2310, WY23205, WY41770, YM09561, YM13162, YS1033, and ZK31945.
Finally, NSAIDs which may also be used include the salicylates, specifically aspirin, and the phenylbutazones, and pharmaceutically acceptable salts thereof.
Pharmaceutical compositions comprising the Formula I compounds may also contain other inhibitors of the biosynthesis of the leukotrienes such as are disclosed in pending U.S. patent applications Ser. No. 539,342, filed Oct. 5, 1983, Ser. No. 459,924, filed Jan. 21, 1983, Ser. No. 539,215, filed Oct. 5, 1983, and Ser. No. 547,161, filed Oct. 31, 1983, which are hereby incorporated herein by reference.
The compounds of the Formula I may also be used in combination with leukotriene antagonists such as those disclosed in copending applications U.S. Ser. Nos. 520,051 and 520,052, filed Aug. 5, 1983 which are hereby incorporated herein by reference and others known in the art such as those disclosed in European Patent Application Nos. 56,172 and 61,800; and in U.K. Patent Specification No. 2,058,785, which are hereby incorporated herein by reference.
Pharmaceutical compositions comprising the Formula I compounds may also contain as the second active ingredient, antihistaminic agents such as benadryl, dramamine, histadyl, phenergan and the like. Alternatively, they may include prostaglandin antagonists such as those disclosed in European Patent Application 11,067 or thromboxane antagonists such as those disclosed in U.S. Pat. No. 4,237,160. They may also contain histidine decarboxyase inhibitors such as .alpha.-fluoromethylhistidine, described in U.S. Pat. No. 4,325,961. The compounds of the Formula I may also be advantageously combined with an H.sub.1 or H.sub.2 -receptor antagonist, such as for instance cimetidine, ranitidine, terfenadine, famotidine, aminothiadiazoles disclosed in EP 81102976.8 and like compounds, such as those disclosed in U.S. Pat. Nos. 4,283,408; 4,362,736; 4,394,508; European Patent Application No. 40,696 and a pending application, U.S. Ser. No. 301,616, filed Sept. 14, 1981. The pharmaceutical compositions may also contain a K.sup.+ /H.sup.+ ATPase inhibitor such as omeprazole, disclosed in U.S. Pat. No. 4,255,431, and the like. Each of the references referred to in this paragraph is hereby incorporated herein by reference.
Another embodiment of the present invention are the novel compounds encompassed by Formula I and the pharmaceutically acceptable salts thereof. These novel compounds are indicated in Table IV.
Some of the compounds described herein contain one or more centers of asymmetry and may thus give rise to diastereoisomers and optical isomers. The present invention is meant to comprehend such possible diastereoisomers as well as their racemic and resolved, optically active forms.
Scheme I, below, illustrates the preparation of compounds of the formula I. ##STR85## where: R.sup.a is C.sub.1 to C.sub.4 alkyl or phenyl,
Reaction of a benzoquinone IV, optimally two equivalents, with 2-aminobenzenethiol V, in a solvent such as acetic acid, acetic acid-water, or a lower alkanol at from -20.degree. to +60.degree. C. for 0.25 to 6 hours yields the phenothiazin-3-one VI. Preferably, the solvent is methanol or ethanol, at 0.degree. to 25.degree. C. for 0.5 to 2 hours. Halogenation of VI to obtain VII may conveniently be carried out using chlorine or bromine in a lower alkanoic acid such as acetic acid at temperatures of 10.degree. to 50.degree. C. Reduction of VII to VIII is carried out with a reducing agent such as sodium hydrosulfite in a suitable solvent system by stirring at from 10.degree. to 50.degree. C. (preferably at room temperature) for 1 to 12 hours (preferably 1 to 4 hours). The solvent system may be a homogeneous one such as dimethylformamide-water or a two-phase system such as ethyl acetate-water or dichloromethane-water.
To prepare a carbamate derivative such as IX, compound VIII is reacted with the appropriate chloroformate reagent in a suitable solvent such as tetrahydrofuran, dioxane or preferably acetonitrile and the mixture heated to reflux for 4 to 24 hours. Reaction of the appropriate chloroalkylcarbamate IX with a metal salt of a carboxylic acid then yields the acyloxyalkoxycarbonyl compound XIV. Preferred salts are those of silver, mercury (II) or sodium, using the corresponding free acid as a solvent, and heating the reaction mixture at 0.degree. to 100.degree. C. for from 10 minutes to 2 hours.
To obtain the N,O-dimethylated compounds X, compound VIII is reacted with a methyl halide or a methyl sulfonate (preferably methyl iodide) in the presence of a strong base such as sodium hydride or potassium t-butoxide in a solvent such as tetrahydrofuran or dimethylformamide at 0.degree. to 60.degree. C. (preferably room temperature) for from 1 to 24 hours (preferably 1 to 10 hours). The O-methylated compounds X are obtained by substituting a weaker base such as Na.sub.2 CO.sub.3 or K.sub.2 CO.sub.3 for sodium hydride or potassium t-butoxide, and stirring at room temperature for 0.25 hours to 5 hours.
The O-acyl compounds XI are prepared by reacting compound VIII with the desired acid anhydride in pyridine at a temperature of from -25.degree. to +75.degree. C. (preferably 0.degree. to 50.degree. C.) for from 1 hour to 24 hours (preferably 4 to 15 hours). Compound XI is transformed into compound XV by reacting it with an acyl halide (bromide or chloride) in a solvent such as dichloromethane, 1,2-dichloroethane or chloroform (preferably dichloromethane) in the presence of 4 Angstrom molecular sieves for a period of 0.5 to 24 hours (preferably 1 to 6 hours) at a temperature of 0.degree. to 60.degree. (preferably room temperature). Hydrolysis of XV to XVI is carried out by reaction with a base such as LiOH, NaOH or KOH, in mixed solvent such as methanol-water or ethanol-water, at from 0.degree. to 60.degree. C. (preferably room temperature) for from 5 minutes to 180 minutes (preferably 10 minutes to 90 minutes). Alternatively, the N-acetyl compound XVI can be prepared from VIII by reacting the latter with an acyl halide, such as acetyl chloride, in a solvent such as dimethyl formamide at from 0.degree. to 50.degree. C. (preferably room temperature) for from 0.5 to 4 hours depending on the rate of reaction of the particular components.
The N,O-diacyl compound XV can also be prepared directly from VIII by treating a mixture of VIII and the appropriate acyl halide in a solvent such as dimethylformamide at from 50.degree. to 150.degree. C. (preferably 75.degree. to 100.degree. C.) for from 2 to 24 hours, preferably from 5 hours to 24 hours to ensure completion of the reaction.
The sulfoxide derivatives XII (n=1) are prepared by treating XI with a peracid such as peracetic acid or meta-chloroperbenzoic acid (MCPBA), in a solvent such as methylene chloride or methylene chloride-methanol for 0.5 to 4 hours at 0.degree. to 30.degree. C. The sulfones XII (n=2) are obtained by reacting XI with a peracid in methylene chloride-methanol, or preferably 1,2-dichloroethane-ethanol, at the reflux temperature of the mixture for 12 to 24 hours, depending upon the rate of reaction. Hydrolysis of XII to XIII is carried out in a manner similar to that described for the conversion of XV to XVI.
The following examples are provided to aid in the interpretation of the claims appearing below. They are not intended as a limitation upon the scope of said claims. Temperatures are in degrees Celsius.
Some of the 3H-phenothiazin-3-one derivatives used as starting materials are described in our co-pending applications U.S. Ser. No. 591,134, filed March 19, 1984 and European Patent Application 84300239.5, published on Aug. 8, 1984 under publication number 0115394. The disclosure of these applications is hereby incorporated herein by reference.
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Feb 1967 |
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Divisions (1)
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654991 |
Sep 1984 |
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Continuation in Parts (1)
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Patent Grant
4845083
