4,7-dihydropyrazolo(3,4-b) pyridine derivatives

Abstract
Novel Ca-blockers, 4,7-dihydropyrazolo[3,4-b]pyridine derivatives having potent antihypertensive and coronary vasodilating actions and useful in treatment for diseases in circulatory system, but without systole inhibitory action.
Description

BACKGROUND OF THE INVENTION
(1) Field of the Invention
The compounds this invention provides are novel Cablocker-type cardiovascular agents having potent antihypertensive and coronary vasodilating effects, and useful in treatment for cardiovascular diseases such as angina pectoris, hypertension, cerebrovascular dysfunction, arrhythmia or the like.
(2) Prior Art
Compounds having Ca-blocking effect have commonly been used for treatment of cardiovascular diseases such as angina pectoris, hypertention, cerebrovascular dysfunction, arrhythmia or the like, and have become well-known because of their high efficacy. In particular, a series of 1,4-dihydropyridine derivatives have been investigated extensively and developed as Ca-blocker. Examples of useful Ca-blockers are Nifedipine (U.S. Pat. Nos. 3,485,847 and 3,644,627), Nisoldipine (Japanese Patent Publication No. 56-47185), 2-amino-1,4-dihydropyridine derivatives (JPN Pat. Pub. No. 57-20306), Nicardipine (JPN Unexamined Pat. Pub. No. 49-109384), 2-pyridyl-1,4-dihydropyridine derivatives (JPN Unexam. Pat. Pub. No. 54-48796), 2-methyldihydropyridine derivatives (JPN Unexam. Pat. Pub. No. 55-62065) and the like. Some examples of pyrazolodihydropyridine derivatives, the production thereof and their Ca-blocking action are disclosed in JPN Pat. Application Nos. 57-176763 and 58-166258 by the present inventors.
SUMMARY
The present invention relates to novel 4,7-dihydropyrazolo[3,4-b]pyridine derivatives and agents for treating cardiovascular diseases. More particularly it relates to 4,7-dihydropyrazolo[3,4-b]pyridine derivatives represented by the formula: ##STR1## wherein X and X' each is hydrogen, nitro, or halogen which may be located at the position or positions 2, 3, and/or 6; R.sup.1 is (a) straight or branched chain C.sub.1 -C.sub.8 alkyl, (b) C.sub.4 -C.sub.6 cycloalkyl which may be substituted by lower alkyl, (c) C.sub.3 -C.sub.7 cycloalkyl(C.sub.1 -C.sub.4)alkyl, (d) C.sub.1 -C.sub.4 alkoxy(C.sub.1 -C.sub.4)alkyl, (e) C.sub.4 -C.sub.7 cycloalkyloxy(C.sub.1 -C.sub.4)alkyl, (f) phenoxy(C.sub.1 -C.sub.4)alkyl, (g) C.sub.1 -C.sub.4 alkylthio(C.sub.1 -C.sub.4)alkyl, (h) C.sub.4 -C.sub.7 cycloalkylthio(C.sub.1 -C.sub.4)alkyl, (i) phenylthio(C.sub.1 -C.sub.4)alkyl, (j) C.sub.1 -C.sub.4 monoalkylamino or C.sub.2 -C.sub.8 dialkylamino-substituted (C.sub.1 -C.sub.4)alkyl, (k) tetrahydrofuryl(C.sub.1 -C.sub.4)alkyl, (l) phenyl(C.sub.1 -C.sub.3)alkyl, which may have one or more substituents of halogen, C.sub.1 -C.sub.4 alkoxy, or trifluoroalkyl, (m) N-benzylpyrrolidinyl, or (n) N-benzylpiperidinyl; R.sup. 2 is hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.4 -C.sub.6 cycloalkyl, or phenyl; and R.sup.3 is hydrogen, C.sub.1 -C.sub.8 straight or branched chain alkyl, C.sub.3 -C.sub.7 cycloalkyl which may be substituted by C.sub.1 -C.sub.4 alkyl, phenyl which may be substituted by chlorine, trifloromethyl, cyano, methoxy, methoxycarbonyl or ethoxycarbonyl, C.sub.7 -C.sub.9 aralkyl, C.sub.1 -C.sub.4 alkoxycarbonyl or 5-or 6-membered heterocyclic group consisting of a .alpha.-pyridyl, .beta.-furyl and 1-methylimidazol-2-yl; or pharmaceutically acceptable acid addition salts thereof.
The objective compounds (I) of this invention are prepared through the Michael addition between heterocyclic amines and .alpha., .beta.-unsaturated ketones accompanied by cyclization reaction. More particularly, the compounds (I) can be produced by the process comprising reacting a compound represented by the formula: ##STR2## wherein R.sup.1 has the same meaning as defined above, with a compound represented by the formula: ##STR3## wherein R.sup.2 and R.sup.3 each has the same meaning as defined above.
Incidentally, the compounds of this invention have the advantage that they have no systole inhibitory action as an adverse reaction usually seen in the use of the analogous known compounds.
DESCRIPTION OF THE PREFERRED ENBODIMENT
In the definition in the formulae (I) to (III), halogen means fluorine, chlorine, bromine, and iodine and, particularly, chlorine is preferred.
Straight or branched chain C.sub.1 -C.sub.8 alkyl includes, for example, methyl, ethyl, i-propyl, t-butyl, n-pentyl, isopentyl, sec-pentyl, neo-pentyl, tert-pentyl, 3-methylpent-3-yl, n-hexyl, iso-hexyl, sec-hexyl, neo-hexyl, tert- hexyl, n-heptyl, iso-heptyl, sec-heptyl, neo-heptyl, tert- heptyl, n-octyl, iso-octyl, sec-octyl, and the like.
C.sub.4 -C.sub.6 Cycloalkyl which may be substituted by lower alkyl includes, for example, cyclobutyl, cyclopentyl, cyclohexyl, 2-i-propyl-4-methylcyclohexyl and the like.
C.sub.3 -C.sub.7 Cycloalkyl includes cyclopropyl, cyclobutyl, cyclohexyl, cycloheptyl and the like.
C.sub.1 -C.sub.4 Alkoxy includes methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, iso-butoxy, tert-butoxy and the like.
C.sub.4 -C.sub.7 cycloalkyloxy includes cyclobutyloxy, cyclopentyloxy, cyclohexyloxy and the like.
C.sub.1 -C.sub.4 Alkylthio includes methylthio, ethylthio, n-propylthio, iso-propylthio, n-butylthio, iso-butylthio, secbutylthio, tert-butylthio and the like.
C.sub.4 -C.sub.7 Cycloalkylthio includes cyclobutylthio, cyclopentylthio, cyclohexylthio, cycloheptylthio and the like.
C.sub.1 -C.sub.4 Monoalkylamino includes methylamino, ethylamino, n-propylamino, iso-propylamino, n-butylamino, iso-butylamino, sec-butylamino, tert-butylamino and the like and C.sub.2 -C.sub.8 dialkylamino includes dimethylamino, methylethylamino, methyl(n-propyl)amino, methyl(iso-propyl)amino, diethylamino, methyl(n-butyl)amino, methyl(iso-butyl)amino, methyl(secbutyl)amino, methyl(tert-butyl)amino, ethyl(n-propyl)amino, ethyl(iso-propyl)amino, ethyl(n-butyl)amino, ethyl(iso-butyl)amino, ethyl(sec-butyl)amino, ethyl(tert-butyl)amino, dipropylamino, n-propyl(n-butyl)amino, n-propyl(iso-butyl)amino, n-propyl(sec-butyl)amino, n-propyl(tert-butyl)amino, iso-propyl(n-butyl)amino, iso-propyl(iso-butyl)amino, isopropyl(sec-butyl)amino, iso-propyl(tert-butyl)amino, dibutylamino and the like.
Tetrahydrofuryl(C.sub.1 -C.sub.4)alkyl includes, for example, 2-tetrahydrofurylmethyl, 3-tetrahydrofurylethyl, and the like.
Phenyl(C.sub.1 -C.sub.3)alkyl which may have one or more substituents of halogen, (C.sub.1 -C.sub.4)alkoxy, or trifluoroalkyl includes, for example, benzyl, phenetyl, 3-phenylpropyl, tolylmethyl, 4-fluorophenethyl, 4-chlorophenethyl, 4-bromophenethyl, 4-iodophenethyl, 3,4-dimethoxyphenethyl, 1-methoxy-2-phenethyl and the like.
Particularly, --NO.sub.2 is the most preferable substituent for X in formulae (I) and (II) and is preferably substituted at the 2 or 3 position of the phenyl.
A preferred group of compounds according to the present invention are 4,7-dihydropyrazolo[3,4-b]pyridine derivatives represented by the formula: ##STR4## wherein X and X.sup.1 each is hydrogen, nitro, or halogen which may be located at the position or positions 2, 3, and/or 6;
R.sup.1 is C.sub.1 -C.sub.4 alkyl; R.sup.2 is hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.4 -C.sub.6 cycloalkyl, or phenyl;
R.sup.3 is hydrogen, C.sub.1 -C.sub.8 straight or branched chain alkyl, C.sub.3 -C.sub.7 cycloalkyl which may be substituted by C.sub.1 -C.sub.3 alkyl, phenyl which may be substituted by chlorine, trifluoromethyl, cyano, methoxy, methoxycarbonyl or ethoxycarbonyl, C.sub.7 -C.sub.9 aralkyl or C.sub.1 -C.sub.4 alkoxycarbonyl; or pharmaceutically acceptable acid addition salts thereof.
Also, a particularly preferred group of compounds according to the present invention are 4,7-dihydropyrazolo[3,4-b]-pyridine derivatives represented by the formula: ##STR5## wherein R.sup.1 is (a) straight or branched chain C.sub.5 -C.sub.8 alkyl, (b) C.sub.4 -C.sub.6 cycloalkyl which may be substituted by lower alkyl, (c) C.sub.3 -C.sub.7 cycloalkyl (C.sub.1 -C.sub.4)alkyl, (d) C.sub.1 -C.sub.4 alkoxy-(C.sub.1 -C.sub.4)alkyl, (e) C.sub.4 -C.sub.7 cycloalkyloxy(C.sub.1 -C.sub.4)alkyl, (f) phenoxy(C.sub.1 -C.sub.4)alkyl, (g) C.sub.1 -C.sub.4 alkylthio(C.sub.1 -C.sub.4)alkyl, (h) C.sub.4 -C.sub.7 cycloalkylthio(C.sub.1 -C.sub.4)alkyl, (i) phenylthio(C.sub.1 -C.sub.4)-alkyl, (j) C.sub.1 -C.sub.4 monalkylamino or C.sub.2 -C.sub.8 dialkylamino-substituted (C.sub.1 -C.sub.4)alkyl, (k) tetrahydrofuryl(C.sub.1 -C.sub.4)alkyl, (l) phenyl(C.sub.1 -C.sub.3)alkyl, which may have one or more substituents of halogen or C.sub.1 -C.sub.4 alkoxy, (m) N-benzylpyrrolidinyl, or (n) N-benzylpiperidinyl; R.sup.2 is C.sub.1 -C.sub.4 alkyl; and R.sup.3 is C.sub.4 -C.sub.6 cycloalkyl or C.sub.3 -C.sub. 7 cycloalkyl-(C.sub.1 -C.sub.4)alkyl; and the pharmaceutically acceptable acid addition salts thereof.
The invention also contemplates agents for treating cardiovascular diseases containing at least one of said compounds described above and a pharmaceutically acceptable carrier.
The compound (I) of the present invention can, as shown in the following scheme, be readily produced by the reaction of .alpha.,.beta.-unsaturated ketone reagent (II) with a 5-aminopyrazole (III), ##STR6## wherein X, X', R.sup.1, R.sup.2 and R.sup.3 each has the same meaning as identified above.
The reaction may be accomplished in the absence or presence of any solvent. Such a solvent as employed for this reaction includes alcohols such as methanol, ethanol, isopropanol, tert-butanol, ethylene glycol and the like; hydrocarbons such as benzene, toluene, xylene and the like; ethers such as ether, tetrahydrofuran, dioxane, glyme, diglyme and the like; halogenohydrocarbons such as dichloromethane, chloroform, dichloroethane, carbon tetrachloride and the like; esters such as ethyl acetate; acetic acid; dimethylformaminde; pyridine; and the like. An acid, an organic base or the like is employed as a catalyst, if necessary. Such an acid includes inorganic acids e.g., sulfuric acid, hydrochloric acid, phosphoric acid and the like; para-toluenesulfonic acid, acetic acid, formic acid and the like as an organic acid; and boron trifluoride, zinc chloride, alminium chloride, magnesium chloride, tin chloride and the like as a Lewis acid. Such a base includes organic base catalysts e.g., triethylamine, pyridine, pyrrolidine, piperidine and the like.
The reaction is completed after a few hours or a few days at room temperature (1.degree.-30.degree. C.) or under heating (30.degree.-100.degree. C.).
The starting compounds, 5-aminopyrazole and .alpha.,.beta.-unsaturated ketone reagents, both of which are employed in the reaction, may be prepared in the manners as shown below, respectively.
(i) Preparation of 5-aminopyrazole (III);
A 5-aminopyrazole (III) can be produced according to the reaction sequence as shown below. In other words, it can be prepared in a high yield by the cyclization of a hydrazine (VI) with a .beta.-ketonitrile (VII). ##STR7## wherein R.sup.2 and R.sup.3 each has the same meaning as defined above, R represents halogen or an ester residue, and M represents an alkali metal.
In the above reaction sequence, the 5-aminopyrazole compounds (III) wherein R.sup.3 is hydrogen may be prepared according to the process A from the compounds (IV) by tosylation and introduction of R.sup.2 followed by elimination of the tosyl group with a base [Chem. Ber. 98, 3368 (1965)]. The compounds (III) wherein R.sup.3 is neither hydrogen nor alkoxycarbonyl may be prepared according to the process B by cyclization reaction of hydrazine or methyl- or phenyl-hydrazines (VI) with a member of .beta.-ketonitriles (VII). The .beta.-ketonitriles (VI) are prepared by reaction of a member of acid chrolides (VIII) with an alkali metal salt of acetonitrile (XII). The compounds (III) wherein R.sup.3 is alkoxycarbonyl are prepared by cyclization reaction of a member of hydrazines (VI) with the alkali metal salt of alkyl 3-cyanopyruvates (X).
(ii) Preparation of .alpha.,.beta.-unsaturated ketone reagents (II):
.alpha.,.beta.-Unsaturated ketone reagents (II) are prepared, as shown in the following scheme, by the condensation reaction of an aldehyde (XI) with an acetoacetic ester (IX); the manner of the reaction is disclosed in J. Chem. Soc., 81, 1212(1902); Chem. Ber., 29, 172(1896); Ann., 218, 170 (1883); J. Chem. Soc., 3092 (1962). ##STR8## wherein X, X', and R.sup.1 each has the same meaning as defined above.
The acetoacetic esters are prepared, in the presence of an acid-(hydrochloric acid, sulfuric acid, phospholic acid and the like) or base-(pyridine, pyrrolidine, piperidine and the like) catalyst, through the reaction of a diketene (XIII) with an alcohol (XIV).
The typical compounds of the present invention, which are prepared by the reaction of the above-obtained .alpha.,.beta.-unsaturated ketone reagents (II) with a 5-aminopyrazole (III), are as follows.
(Compounds list part 1)
Ethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-isopropyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-(n-butyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-cyclobutyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5carboxylate,
Methyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Isopropyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-cyclopentyl-1,6-dimethyl-4-(2-chlorophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-cyclopentyl-1,6-dimethyl-4-(2,6-dichlorophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-cyclohexyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-benzyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-phenyl-6-methyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 1,3-diphenyl-6-methyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-phenyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-phenyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-phenyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-(3-chlorophenyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-(3,5-dichlorophenyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-(3,5-dichlorophenyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-(3-trifluoromethylphenyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-(3-cyanophenyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-(3-methoxycarbonylphenyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-(3-ethoxycarbonylphenyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-(.alpha.-pyridyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-(.beta.-furyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-methoxycarbonyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-ethoxycarbonyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-isopropoxycarbonyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Ethyl 3-(4-methoxyphenyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 1,3-dicyclopentyl-6-methyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-isobutyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-(t-butyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-(n-pentyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-(3-methylpent-3-yl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-cyclopropyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-cyclohexyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-cycloheptyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-(4-methylcyclohexyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-(1-ethylcyclohexyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
Methyl 3-(1-methylimidazol-2-yl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate, (Compounds list part 2)
(1) 2-Methoxyethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(2) 2-Methoxyethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(3) 2-Methoxyethyl 3-cyclohexyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(4) 2-Methoxyethyl 3-cyclopentylmethyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(5) 2-Isopropoxypropyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(6) 2-Cyclopentyloxyethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(7) 2-Cyclohexyloxyethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(8) 2-Tetrahydrofurylmethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(9) 2-Phenoxyethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(10) 2-Phenoxyethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(11) 2-Phenoxyethyl 3-cyclohexyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(12) 2-Methylthioethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(13) 3-dimethylaminopropyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(14) N-Benzylpyrrolidin-3-yl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(15) N-Benzylpiperidin-4-yl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(16) n-Pentyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(17) Phenethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(18) 4-Chlorophenethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(19) 3,4-Dimethoxyphenethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(20) 1-Methoxy-2-phenylethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(21) 2-Isopropyl-4-methylcyclohexyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(22) 2-Phenylthioethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(23) 2-Isopropylthioethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(24) 2-Cyclopentylthioethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(25) 2-Cyclopentylethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(26) Cyclohexylmethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate,
(27) Cyclopentyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate, and
(28) Cyclohexyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate.
In addition, the acid addition salts, which can be obtained from the above-listed compounds, can be used as an active ingredient in this invention. Some examples of the acids capable to form such salts are inorganic acids such as hydrohalogenic acid (hydrochloric acid, hydrobromic acid or the like), sulfuric acid, nitric acid, phospholic acid or the like; and organic acids such as acetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, malic acid, maleic acid, fumaric acid, citric acid, benzoic acid, methanesulfonic acid or the like.
[Effect and Use]
The novel compounds of the present invention have the advantage that they have excellent antihypertensive and coronary vasodilating actions derived from Ca-blocking action, but have no systole inhibitory action which is one of adverse reactions and have been a defect of the conventional Ca-blockers. The biological tests of the following compounds were performed as explained below.
(Compounds Tested: Part 1)
(A): Nifedipine
(B-1): Methyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(C-1): Ethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate hydrochloride
(Compounds Tested: Part 2)
(A): Nifedipine
(B-2): 2-Methoxyethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(C-2): 2-Methoxyethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(D): 2-Methoxyethyl 3-cyclohexyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(E): 2-Methoxyethyl 3-cyclopentylmethyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(F): 3-Isopropoxypropyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(G): 2-Cyclopentyloxyethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(H): 2-Tetrahydrofurylmethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(I): 2-Phenoxyethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(J): 2-Methylthioethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(K): Phenethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(L): 4-Chlorophenethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(M): 3,4-Dimethoxyphenethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate
(Test Method)
(1) Antihypertensive Action:
Female Spontaneously Hypertensive Rats(hereinafter referred to as SHR) with 160 mmHg of systolic pressure were employed without anaesthetization. The systolic pressure was, after SHRs were kept warm at 50.degree. C. for 2 to 3 minutes, bloodlessly measured by the tail-cuff method [Japan J. Pharmacol., 28, 617 (1978)] using a Physiograph and an Electrosphygmomanometer (DMP-4B, PE-300, Narco Biosystems, Inc., Houston). Each compound was intraperitoneally administered to SHR at a dose of 3 mg per kilogramm.
(Result)
TABLE 1______________________________________(Part 1) Maximum Hypotension Duration of EffectCompounds (mmHg) (hours)______________________________________(A) 45 6(B-1) 66 16(C-1) 42 14______________________________________
(2) Coronary Vasodilating Action and Systole Inhibitory Action:
Guinea pigs with 400-800g of body weight were hit strongly on their heads and the cartoid artery of each Guinea pigs was cut down in order to make them bloodless. The heart was isolated and perfused with at a constant pressure (50 cm H.sub.2 O) by the Langendorff method [Basic Pharmacology & Therapeutics, 9(4), 181 (1981)]. Krebs-Ringer bicarbonate solution (27.degree. C.) containing 0.5% defibrinated blood was employed as a perfusate, into which a mixed gas of 95% oxygen and 5% carbon dioxide was continuously introduced. The flowing perfusate was led into a drop counter, and the changes of the flow i.e. increase and decrease are regarded as the respective indications for coronary vasodilation and vasoconstriction. The isomeric contraction of apex and the number of drops of the coronary perfusate were recorded on a Recticorder (RJG 3006, Nihon Koden) by way of an F-D Pick-up (SB-IT, Nihon Koden). Each of the test compounds at a dose of 0.1 .mu.g was administered through the short rubber tube connecting the aorta and the cannula.
(Results)
Antihypertensive action is shown in a maximal decrease of blood pressure, i.e. a maximum difference between systolic pressures after and before the administration of the test compound; along with which the duration period is also shown.
Coronary vasodilating action is shown in changes of the quantiy of the perfusate, and systole inhibitory action is shown in those of inotropic tension.
(Result)
TABLE 2______________________________________Coronary vasodilating action(Part 1) Perfusion Flow Change (%)Compounds 0.1 .mu.g 1 .mu.g 10 .mu.g______________________________________(A) +38 +100(B-1) +26 +73 +180(C-1) +40 +79 +93______________________________________
TABLE 3______________________________________Negative inotropic action(Part 1) Change of Contractile Tension (%)Compounds 0.1 .mu.g 1 .mu.g 10 .mu.g______________________________________(A) -15 -57(B-1) 0 0 0(C-1) 0 0 0______________________________________
TABLE 1__________________________________________________________________________(Part 2)Antihypertensive action, coronary vasodilating action andsystole inhibitory action: Perfusion Maximum Duration of Flow Change of Con-Com- Hypertension Effect Change tractile Tensionpound (mmHg) (hours) (%) (%)__________________________________________________________________________(A) 45 6 +38 -15(B-2) 45 6 +28 0(C-2) 36 6 +15 0(D) 65 6 +32 0(E) 26 6 +20 0(F) 53 6 +65 0(G) 53 6 +67 0(H) 0 -- +34 0(I) 74 6 +43 0(J) 20 6 +68 0(K) 75 6 +63 0(L) 74 6 -- --(M) 86 6 -- --__________________________________________________________________________
(3) Acute Toxicity:
In female DS mice (body weight: about 20g), LD.sub.50 value after the intravenous administration of the compounds was calculated by the Brownlee's up and down method [J. Am. Sat. As., 48, 262 (1953)].
TABLE 4______________________________________(Part 1)Compounds LD.sub.50 (mg/kg)______________________________________(A) 10.7(B-1) 31.5(C-1) 50.6______________________________________
Since the compounds of this invention, as clearly seen from the above-listed results, show the highly antihypertensive and coronary vasodilating actions but no systole inhibitory action with low acute toxicity, they can be used as a cardiovascular agent with lesser adverse reactions to human or animals.
The compounds of this invention and the acid addition salts thereof can orally or pareterally be administered to human or animals and can be manufactured in various formulations in compliance with the usage. They, for instance, can be in a formulation of tablets, capsules, pills, granules, fine granules, aqueous solutions, emulsions or the like. In the course of the formulation, conventional carriers or diluents such as lactose, sucrose, starch, cellulose, talc, magnesium stearate, magnesium oxide, calcium sulfate, powdered gum arabic, gelatin, sodium arginate, sodium benzoate, stearic acid and the like are employed. Injections used may be in a formulation of a solution with distilled water, saline solution, Ringer solution or the like, or a suspension in sesame oil.
The compounds of this invention may be administered to an adult orally at a dose of about 1-50 mg a day, or intravenously at about 0.5-20 mg a day.
The present invention is further described in the following Examples and Preparations.





EXAMPLE 1 (Part 1)
Preparation of ethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate ##STR9##
A mixture of 0.83 g (5 mmol) of 5-amino-3-cyclopentyl-1-methylpyrazole 1 and 1.32 g (5 mmol) of ethyl 3-nitrobenzylidene acetate 2 in 10 ml of t-butanol is heated at 80.degree. C. under nitrogen gas for 3 days. The mixture is concentrated under reduced pressure, and the resulting residue is dissolved in chloroform, washed with an aqueous sodium bicarbonate solution and then with an a aqueous sodium chloride solution. The solution is dried with magnesium sulfate and chromatographed on a column of silica gel. The chloroform-ethyl acetate (20:1) fraction gives 2 g of the objective compound as an yellow oily material.
IR: .nu..sub.max.sup.Nujol 3270, 3150, 1690, 1350 cm.sup.-1
NMR: .delta..sup.CDCl 3 1.17 (3H, t), 1.00-2.80 (9H, m), 2.38, 3.67 (3H.times.2, s), 4.03 (2H, q), 5.25 (1H, s), 7.13-8.10 (4H, m)
The objective compound (2 g) is converted into the hydrochloride on treatment with an ether-hydrochloric acid mixture, which is recrystallized from acetone to give 1.75 g of the hydrochloride. (Yield: 78.4%) m.p. 170.degree.-173.degree. C.
Elemental analysis
Calcd (%): C, 59.12; H, 6.09; N, 12.54 (for C.sub.22 H.sub.26 N.sub.4 O.sub.4.HCl)
Found (%): C, 58.90; H, 6.10; N, 12.57
IR: .nu..sub.max.sup.Nujol 2630, 2550, 1680, 1347 cm.sup.-1
NMR: .delta..sup.CDCl 3 0.93-2.90 (9H, m), 1.17 (3H, t), 2.61 (3H, s) 4.03 (2H, q), 6.03 (1H), 5.22 (1H, s), 7.23-8.17 (4H, m)
EXAMPLES 2-42 (Part 1)
In the same manner as in Example 1, the compounds described in Table 5 can be prepared. Tables 6 and 7 show the data of each product, i.e. physical constants, elemental analysis, IR spectra, and NMR spectra.
TABLE 5__________________________________________________________________________ ##STR10##Ex. R.sup.1 R.sup.2 R.sup.3 X, X' Yield (%)__________________________________________________________________________2 C.sub.2 H.sub.5 CH.sub.3 H 3-NO.sub.2,H 47.43 CH.sub.3 " " 2-NO.sub.2,H 42.14 " " i-C.sub.3 H.sub.8 3-NO.sub.2,H 92.6*5 " " n-C.sub.4 H.sub.9 " 96.76 " " ##STR11## " 68.57 " " ##STR12## 2-NO.sub.2,H 77.68 " " " 3-NO.sub.2,H 60.69 i-C.sub.3 H.sub.8 " " " 68.2*10 C.sub.2 H.sub.5 " " 2-Cl,H 59.0*11 " " " 2,6-Cl.sub.2 15.712 CH.sub.3 " ##STR13## 3-NO.sub.2,H 71.7*13 " " ##STR14## " 71.4*14 C.sub.2 H.sub.5 H ##STR15## " 99.015 " ##STR16## " " 79.216 CH.sub.3 CH.sub.3 ##STR17## 3-NO.sub.2,H 91.117 C.sub.2 H.sub.5 " " " 83.718 CH.sub.3 " " 2-NO.sub.2,H 84.219 C.sub.2 H.sub.5 " ##STR18## 3-NO.sub.2,H 94.520 CH.sub.3 " ##STR19## " 84.521 C.sub.2 H.sub.5 " " " 51.322 " " ##STR20## " 74.123 " " ##STR21## " 68.324 " " ##STR22## " 78.325 " " ##STR23## " 81.026 " " ##STR24## " 75.727 CH.sub.3 " ##STR25## " 77.728 " " COOCH.sub.3 " 59.829 C.sub.2 H.sub.5 " COOC.sub.2 H.sub.5 " 58.930 CH.sub.3 " COOi-C.sub.3 H.sub.8 " 56.531 C.sub.2 H.sub.5 " ##STR26## " 80.432 CH.sub.3 ##STR27## ##STR28## " 71.833 " CH.sub.3 i-C.sub.4 H.sub.9 " 59.034 " " t-C.sub.4 H.sub.9 " 38.835 " " n-C.sub.5 H.sub.11 " 85.7*36 " " ##STR29## " 57.4*37 " " ##STR30## " 73.738 " " ##STR31## 2-NO.sub.2,H 79.639 " " ##STR32## 3-NO.sub.2,H 95.240 " " ##STR33## " 53.241 " " ##STR34## " 59.6*42 " " ##STR35## " 76.8__________________________________________________________________________ *Hydrochloride
TABLE 6__________________________________________________________________________(Part 1) Elemental AnalysisAppear- Solvent in Calcd. Found.Ex. ance* Recrystallization M.P. (.degree.C.) Molecular Formula C H N C H N__________________________________________________________________________2 YP Ethyl acetate 153-154 C.sub.17 H.sub.18 N.sub.4 O.sub.4 59.64 5.30 16.37 59.68 5.25 16.333 " Isopropanol 213-214 C.sub.16 H.sub.16 N.sub.4 O.sub.4 58.53 4.91 17.07 58.68 4.89 17.144 " Methanol 214-220 C.sub.20 H.sub.24 N.sub.4 O.sub.4.HCl 57.21 5.76 13.34 56.93 5.97 13.365 OP Ether 129-132 C.sub.20 H.sub.24 N.sub.4 O.sub.4 62.48 6.29 14.58 62.52 6.31 14.466 YP Ethyl acetate 183-185 C.sub.20 H.sub.22 N.sub.4 O.sub.4 62.81 5.80 14.65 62.63 5.83 14.587 " Ethanol 208-213 C.sub.21 H.sub.24 N.sub.4 O.sub.4 63.62 6.10 14.13 63.50 6.15 14.108 " Isopropyl ether 172-173 C.sub.21 H.sub.24 N.sub.4 O.sub.4 63.62 6.10 14.13 63.42 6.08 14.079 CP Isopropanol 170-190 (dec.) C.sub.23 H.sub.25 N.sub.4 O.sub.4.HCl.1/2H.su b.2 O 59.29 5.84 12.03 59.72 6.31 12.0310 " Methanol-Acetone 160-170 (dec.) C.sub.22 H.sub.26 N.sub.3 O.sub.2 Cl.HCl 60.55 6.24 9.63 60.63 6.31 9.7511 " Isopropyl ether 146-148 C.sub.22 H.sub.25 N.sub.3 O.sub.2 Cl.sub.2.1/ 2H.sub.2 O 59.60 5.91 9.47 59.56 6.04 9.4112 YP Methanol 195-230 (dec.) C.sub.22 H.sub.26 N.sub.4 O.sub.4.HCl 59.13 6.09 12.54 58.76 6.09 12.5013 CP Methylene chloride- 124-126 C.sub.23 H.sub.22 N.sub.4 O.sub.4.HCl.1/2H.su b.2 O 59.54 5.22 12.07 59.35 5.36 11.83 Ether14 YP Benzene 233-234 C.sub.22 H.sub.20 N.sub.4 O.sub.4 65.33 4.99 13.86 65.23 4.83 13.9315 " Ethyl acetate 214-215 C.sub.28 H.sub.24 N.sub.4 O.sub.6 69.99 5.03 11.66 70.28 5.09 11.6816 OP " 209-210 C.sub.22 H.sub.20 N.sub.4 O.sub.4 65.23 4.99 13.86 65.42 4.91 13.8917 YN Methylene chloride- 157-158 C.sub.23 H.sub.22 N.sub.4 O.sub.4 66.01 5.30 13.39 65.94 5.16 13.33 Ether18 OP Chloroform 205-206 C.sub.22 H.sub.20 N.sub.4 O.sub.4.1/2H.sub.2 O 63.91 5.12 13.55 64.17 5.06 13.6419 YP Ethanol 214-216 C.sub.23 H.sub.21 N.sub.4 O.sub.4 Cl 61.00 4.67 12.37 61.03 4.43 12.3820 " Tetrahydrofuran- 263-264 C.sub.22 H.sub.18 N.sub.4 O.sub.4 Cl.sub.2 55.82 3.83 11.84 55.80 3.82 11.74 Ethanol21 " Methylene chloride- 222-224 C.sub.23 H.sub.20 N.sub.4 O.sub.4 Cl.sub.2 56.68 4.14 11.50 56.32 4.22 11.43 Ether22 " Methanol 217-218 C.sub.24 H.sub.21 N.sub.4 O.sub.4 F.sub.3 59.25 4.35 11.52 59.31 4.39 11.5623 YN " 211-214 C.sub.24 H.sub.21 N.sub.5 O.sub.4 65.00 4.77 15.79 64.87 4.89 15.6724 OP Ethanol 182-183 C.sub.25 H.sub.24 N.sub.4 O.sub.6 63.01 5.08 11.76 62.93 5.11 11.8025 YN Methanol 225-227 C.sub.26 H.sub.26 N.sub.4 O.sub.6 63.66 5.34 11.42 63.42 5.36 11.3926 YP Isopropanol 213-214 C.sub.22 H.sub.21 N.sub.5 O.sub.4 63.00 5.05 16.70 63.16 4.94 16.6327 " Ethanol 195-198 C.sub.20 H.sub.18 N.sub.4 O.sub.5 60.91 4.60 14.21 60.85 4.70 14.0828 " Ethyl acetate 206-209 C.sub.18 H.sub.18 N.sub.4 O.sub.6 55.95 4.70 14.50 55.91 4.71 14.4029 YN " 133-135 C.sub.20 H.sub.22 N.sub.4 O.sub.6 57.96 5.35 13.52 57.29 5.34 12.9730 YP " 180-182 C.sub.20 H.sub.22 N.sub.4 O.sub.6 57.96 5.35 13.52 57.73 5.36 13.3031 " " 159-161 C.sub.24 H.sub.24 N.sub.4 O.sub.5 64.27 5.39 12.49 64.33 5.42 12.4832 OP Ethanol 175-177 C.sub.25 H.sub.30 N.sub.4 O.sub.4 66.66 6.71 12.44 66.68 6.68 12.4433 YP Ethyl acetate 110-115 C.sub.20 H.sub.24 N.sub.4 O.sub.4 62.48 6.29 14.58 62.12 6.12 14.7634 " " 153-154 C.sub.20 H.sub.24 N.sub.4 O.sub.4.1/2H.sub.2 O 61.06 6.40 14.24 61.25 6.52 13.8835 " Ethanol 140-155 C.sub.21 H.sub.26 N.sub.4 O.sub.4.HCl 58.00 6.26 12.88 58.03 6.37 12.7136 CP Acetone 172-175 C.sub.22 H.sub.28 N.sub.4 O.sub.4.HCl 58.86 6.51 12.48 58.59 6.47 12.4637 YP Ethyl ether 100-102 C.sub.19 H.sub.20 N.sub.4 O.sub.4 61.94 5.47 15.21 61.84 5.56 15.0538 " Methyl cyanide 215-219 C.sub.22 H.sub.26 N.sub.4 O.sub.4 64.37 6.39 13.65 64.21 6.31 13.5239 " Ethyl ether 199-200 C.sub.23 H.sub.28 N.sub.4 O.sub.4 65.07 6.65 13.20 65.13 6.77 13.1040 " Isopropanol 197-198 C.sub.23 H.sub.28 N.sub.4 O.sub.4 65.07 6.65 13.20 65.09 6.60 13.0541 PL Ethanol 175-176 C.sub.24 H.sub.30 N.sub.4 O.sub.4.HCl 60.69 6.58 11.80 60.35 6.43 11.7742 YN Methanol 207-208 (dec.) C.sub.20 H.sub.20 N.sub.6 O.sub.4.CH.sub.3 OH 57.00 5.92 19.00 57.10 5.48 19.05__________________________________________________________________________ *YP = Yellow prisms, CP = Colorless prisms, OP = Orange prisms, YN = Yellow needles, PL = Colorless plates
TABLE 7__________________________________________________________________________(Part 1)IR (.nu..sub.max.sup.cm.spsp.-1)Ex. NH CO NO.sub.2 NMR (.delta..sup.CDCl 3)__________________________________________________________________________2 3340 1690 1343 1.10(3H,t), 2.45(3H,s), 3.70(3H,s), 4.00(2H,q), 5.30(1H,s), 7.00(1H,s), 7.20(1H,bs), 7.30-8.10(4H,m)3 3280 3175 1680 1350 2.45(3H,s), 3.40(3H,s), 3.70(3H,s), 5.70(1H,s), 6.80(1H,bs), 7.30-7.85(4H,m)4 3430 3290 1690 1350 0.90(3H,d), 1.10(3H,d), 1.20(3H,t), 2.40(3H,s), 2.20-2.80(1H,m), 3.70(3H,s), 4.05(2H,m), 5.30(1H,s), 6.90(1H,bs), 7.35-8.10(4H,m)5 3350 1693 1345 0.53-1.53(7H,m), 2.20(2H,m), 2.40(3H,s), 3.59(3H,s), 3.68(3H,s), 5.25(1H,s), 7.44(1H,bs), 7.23-8.13(4H,m)6 3375 1705 1350 2.10-3.07(7H,m), 2.37(3H,s), 3.56(3H,s), 3.65(3H,s), 5.16(1H,s), 7.37-7.90(5H,m)7 3290 1673 1353 0.87-3.10(9H,m), 2.32(3H,s), 3.32(3H,s), 3.67(3H,s), 5.62(1H,s), 7.10-14 7.83(4H,m)8 3375 1700 1380 1.17-2.83(9H,m), 2.27(3H,s), 3.58(3H,s), 3.67(3H,s), 5.25(1H,s), 6.70(1H,bs), 7.27-8.10(4H,m)9 2560 1693 1353 *1.03(3H,d), 1.25(3H,d), 1.53-2.60(9H,m), 2.38(3H,s), 3.65(3H,s), 4.90(2H,q), 5.23(1H,s), 7.40-7.93(5H,m)10 2360 1701 *1.17(3H,t), 1.60-2.80(9H,m), 2.38(3H,s), 3.52(3H,s), 4.02(2H,q), 5.62(1H,s), 7.13-8.10(5H,m)11 3470 3280 1670 1.07(3H,t), 0.80-3.27(9H,m), 2.30(3H,s), 3.57(3H,s), 3.99(2H,q), 6.08(1H,s), 6.90-7.80(5H,m)12 2495 1699 1352 *0.77-2.57(11H,m), 2.42(3H,s), 3.62(3H,s), 3.70(3H,s), 5.30(1H,s), 7.26(1H,bs), 7.43-8.02(3H,m)13 3200 1690 1350 2.30(3H,s), 3.52(3H,s), 3.60(5H,s), 5.00(1H,s), 6.73-8.23(4H,m)14 3200 3110 1705 1347 **1.15(3H,t), 2.50(3H,s), 4.03(2H,q), 6.17(1H,bs), 6.45(1H,s), 7.10-8.17(9H,m), 10.33(1H,bs)15 3360 1698 1345 **1.13(3H,t), 2.43(3H,t), 4.02(2H,q), 5.62(1H,s), 6.90(1H,bs), 7.13-8.03(9H,m)16 3350 1665 1373 **2.42(3H,s), 3.50(3H,s), 3.80(3H,s), 5.52(1H,s), 7.03-7.93(14H,m), 9.57(1H,bs)17 3280 1678 1350 1.18(3H,t), 2.49(3H,s), 3.77(3H,s), 4.07(2H,q), 5.50(1H,s), 6.78(1H,bs), 7.13-8.03(9H,m)18 3315 1675 1375 2.32(3H,s), 3.35(3H,s), 3.80(3H,s), 6.05(1H,s), 7.07-7.77(9H,m), 9.60(1H,bs)19 3340 1690 1346 1.20(3H,t), 2.45(3H,s), 3.80(3H,s), 4.10(2H,q), 5.50(1H,s), 6.55(1H,bs), 7.10-8.10(9H,m)20 3355 1683 1350 2.40(3H,s), 3.53(3H,s), 3.83(3H,s), 5.47(1H,s), 7.20-8.00(8H,m), 9.60(1H,bs)21 3350 1692 1350 1.25(3H,s), 2.43(3H,s), 3.80(3H,s), 4.12(2H,q), 5.48(1H,s), 7.03-810(7H,m)22 3340 1692 1348 1.22(3H,t), 2.45(3H,s), 3.80(3H,s), 4.08(2H,q), 5.50(1H,s), 6.45(1H,bs), 7.17-8.02(7H,m)23 3350 1692 1348 1.20(3H,t), 2.45(3H,s), 3.82(3H,s), 4.07(2H,q), 5.50(1H,s), 7.12(1H,bs), 7.18-8.05(8H,m)24 3330 1723 1694 1343 1.22(3H,t), 2.43(3H,s), 3.80(3H,s), 3.93(3H,s), 4.09(2H,q), 5.60(1H,s), 7.18(1H,bs), 7.12-8.22(8H,m)25 3270 1712 1668 1350 1.20(3H,t), 1.40(3H,t), 2.47(3H,s), 3.83(3H,s), 4.09(2H,q), 4.40(2H,q), 5.60(1H,s), 6.60(1H,bs), 7.07-8.23(8H,m)26 3360 1695 1355 1.20(3H,t), 2.45(3H,s), 3.70(3H,s), 4.05(2H,q), 5.80(1H,s), 6.80(1H,bs), 7.00-8.70(8H,m)27 3360 1701 1350 2.39(3H,s), 3.64(3H,s), 3.74(3H,s), 5.36(1H,s), 6.50-8.63(8H,m)28 3320 1725 1700 1355 2.39(3H,s), 3.58(3H,s), 3.75(3H,s), 3.78(3H,s), 5.50(1H,s), 7.26-7.88(7H,m), 7.60(1H,bs)29 3220 3120 1735 1693 1350 1.20(3H,t), 1.30(3H,t), 2.42(3H,s), 3.80(3H,s), 4.07(2H,q), 4.29(2H,q), 5.58(1H,s), 7.45(1H,bs), 7.18-8.15(4H,m)30 3370 1725 1693 1350 1.20(3H,d), 1.32(3H,d), 2.38(3H,s), 3.63(3H,s), 3.78(3H,s), 5.17(1H,m), 5.58(1H,s), 7.35-8.02(4H,m), 8.07(1H,bs)31 3290 1630 1350 1.18(3H,t), 2.43(3H,s), 3.77(6H,s), 4.07(2H,q), 5.50(1H,s), 6.67-8.07(9H,m)32 3350 1695 1340 1.22-2.20(16H,m), 2.40(3H,s), 2.62(1H,m), 3.58(3H,s), 4.35(1H,m), 5.25(1H,s), 4.35(1H,bs), 7.30-8.13(4H,m)33 3220 1690 1347 0.70, 0.84(6H,d), 1.82(3H,m), 2.40, 3.57, 3.67(9H,s), 5.20(1H,s), 7.08(1H,bs), 7.62(4H,m)34 3300 1700 1350 1.08(9H,s), 2.42, 3.72, 3.78(9H,s), 5.45(1H,s), 6.57(1H,bs), 7.67(4H,m)35 2560 1701 1347 0.53-1.62(9H,m), 2.22(2H,m), 2.37, 3.55, 3.63(9H,s), 5.20(1H,s), 7.12-8.20(4H,m) 2.73(1H,bs)36 2640 1710 1350 0.33, 0.58(6H,d), 1.07, 2.34, 3.68, 3.73(12H,s), 1.49(4H,m), 5.32(1H,s) 7.13(1H,bs), 7.65(4H,m)37 3225 1695 1350 0.27-1.67(5H,m), 2.40, 3.57, 3.60(9H,s), 5.28(1H,s), 7.02(1H,bs), 7.15-8.07(4H,m)38 3320 1685 1360 0.70-2.87(11H,m), 2.37, 3.50, 3.67(9H,s), 5.87(1H,s), 7.12(1H,bs), 7.00-7.83(4H,m)39 3355 1700 1350 1.07-2.62(13H,m), 2.40, 3.58, 3.67(9H,s), 5.25(1H,s), 6.97(1H,bs), 7.28-8.12(4H,m)40 3340 1695 1340 0.70-2.35(10H,m), 0.84(3H,d), 2.41, 3.59, 3.68(9H,s), 5.27(1H,s), 6.79(1H,bs) 7.30-8.15(4H,m)41 2600 1666 1344 0.33(3H,t), 0.73-2.53(12H,m), 2.36, 3.68, 3.73(9H,s), 5.30(1H,s), 6.88(1H,bs) 7.11-8.01(4H,m)42 1667 1347 2.65, 3.18, 3.44, 3.60(12H,s), 5.38(1H,s), 6.82-7.88(6H,m), 8.65(1H,bs)__________________________________________________________________________ *Free base **in DMSOd.sub.6
EXAMPLE 43 (Part 1)
Component (Tablet)
______________________________________Ethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo-[3,4-b]pyridine-5-carboxylate 10 mgCorn starch 50 mgGelatin 7.5 mgAvicel (microcrystalline cellulose) 25 mgMagnesium stearate 2.5 mgTotal 95 mg______________________________________
The above composition is formulated into one tablet.
Reference example 1 (Part 1)
(i) Preparation of 5-amino-3-isopropyl-1-methylpyrazole ##STR36##
A mixture of 8.0 g (72 mmol) of 1-cyano-3-methyl-2-butanone 4 and 3.4 g (73.8 mmol) of methylhydrazine 5 in 2 ml of ethanol is stirred at room temperature for an hour, and concentrated under reduced pressure. The resulting residue is chromatographed on silica gel. The chloroform fraction is recrystallized from carbon tetrachloride to give 8.48 g (84.6% yield) of the titled compound as colorless prisms.
m.p. 111.degree.-112.degree. C.
NMR: .delta..sup.CDCl 3 1.20 (6H, d), 2.60-3.10 (1H, m), 3.40 (2H, bs), 3.60 (3H, s), 5.30 (1H, s)
(ii) Preparation of 1-cyano-3-methyl-2-butanone ##STR37##
To a solution (100 ml) of 0.2 mol of n-butyllithium in anhydrous tetrahydrofuran is added dropwise a solution of 8.2 g (0.2 mmol) of acetonitrile in 12 ml of tetrahydrofuran under nitrogen gas at -70.degree. C. within 30 minutes; after 2 hours, a solution of 10.65 g (0.1 mmol) of isobutyrylchloride in 18 ml of tetrahydrofuran is added dropwise thereto. After an hour, the reaction mixture is acidified with 10% hydrochloric acid and extracted with ether, and the extract is washed with an aqueous sodium chloride solution, dried with magnesium sulfate, and evaporated. The residue is distilled to give 8.05 g (72.5% yield) of the objective compound.
m.p. 62.degree.-65.degree. C.
NMR: .delta..sup.CDCl 3 1.2 (6H, d), 2.6-3.1 (1H, m), 3.5 (2H, m)
Reference examples 2-19 (Part 1)
In the same manner as in Reference example 1, the compounds described in Table 8 can be prepared.
TABLE 8__________________________________________________________________________Ref. Yield M.P.Ex. R.sup.2 R.sup.3 (%) (.degree.C.) NMR (.delta.CDCl.sub.3)__________________________________________________________________________2 CH.sub.3 n-C.sub.4 H.sub.9 89.1 0.70-2.00(7H,m), 2.60(2H,t), 3.54(3H,s), 5.29(1H,s)3 " ##STR38## 68.2 117-118 1.50-3.33(7H,m), 3.54(3H,s), 3.60(2H,bs), 5.38(1H,s)4 " ##STR39## 74.4 149-150 1.33-2.20(8H,m), 2.60-3.10(1H,m), 3.57(5H,s), 5.32(1H,s)5 " ##STR40## 71.7 173-174 0.90-2.77(11H,m), 3.43(2H,bs), 3.57(3H,s), 5.32(1H,s)6 " ##STR41## 89.2 130-131 3.40(2H,bs), 3.53(3H,s), 3.78(2H,s), 5.22(1H,s), 7.23(5H,s)7 H ##STR42## 94.3 110-111 4.75(2H,bs), 5.80(1H,s), 7.10-7.77(5H,m) ##STR43## " 78.0 130-131 5.83(1H,s), 7.20-7.80(5H,m)9 CH.sub.3 " 92.4 130-131 3.58(3H,s), 3.50(2H,bs), 5.73(1H,s), 7.15-7.78(5H,m)10 " ##STR44## 31.0 127-128 3.65(3H,s), 5.80(1H,s), 7.10-7.80(4H,m)11 " ##STR45## 99.1 155-156 3.63(3H,s), 3.63(2H,bs), 5.72(1H,s), 7.07-7.67(3H,m)12 " ##STR46## 62.2 91-92 3.58(2H,bs), 3.68(3H,s), 5.85(1H,s), 7.30-8.07(4H,m)13 " ##STR47## 79.1 179-181 3.55(2H,bs), 3.69(3H,s), 5.81(1H,s), 7.48-7.85(4H,m)14 " ##STR48## 76.8 101-102 3.63(2H,bs), 3.68(3H,s), 3.90(3H,s), 5.88(1H,s), 7.42-8.37(4H,m)15 CH.sub.3 ##STR49## 77.9 113-114 1.38(3H,t), 3.62(2H,bs), 3.68(3H,s), 4.38(2H,q), 5.88(1H), 7.40-8.36(4H,m)16 " ##STR50## 53.5 186-187 3.65(2H,bs), 3.70(3H,s), 6.15(1H,s), 7.00-8.00(4H,m)17 " ##STR51## 14.2 118-120 3.52(2H,bs), 3.65(3H,s), 5.63(1H,s), 6.68-7.69(3H,m)18 " ##STR52## 75.1 140-141 3.65(3H,s), 3.78(3H,s), 5.75(1H,s), 6.73-7.67(4H,m)19 ##STR53## ##STR54## 71.5 92-93 1.2-2.33(16H,m), 2.97(1H,m), 3.42(2H,bs), 4.35(1H,m),__________________________________________________________________________ 5.33(1H,s)
Reference example 20 (Part 1)
Preparation of ethyl 5-amino-1-methylpyrazole-3-carboxylate ##STR55##
A mixture of 10 g (61.3 mmol) of the sodium salt of ethyl 3-cyanopyruvate 10 and 9.0 g (61.3 mmol) of methylhydrazine sulfate 9 in 100 ml of methanol is stirred at room temperature for 3 days, and then concentrated under reduced pressure. To the resulting residue are added an aqueous sodium bicarbonate solution and an aqueous sodium chloride solution, and the mixture is extracted 6 times with chloroform, dried with magnesium sulfate, and chromatographed on a column of silica gel. The ethyl acetate eluate gives 6.54 g (62.9% yield) of the objective compound 11 as an yellow oil.
NMR: .delta..sup.CDCl 3 1.35 (3H, t), 3.71 (3H, s), 3.76 (2H, bs), 4.35 (2H, q), 6.03 (1H, s)
Reference example 21 (Part 1)
Preparation of methyl 5-amino-1-methylpyrazole-3-carboxylate
To a solution of 48 mg (2.1 mmol) of sodium in 40 ml of methanol is added 2.0 mg (11.8 mmol) of 5-amino-3-ethoxycarbonyl-1-methylpyrazole, and the mixture is refluxed over night, and distilled under reduced pressure. To the resulting residue are added a small amount of water and sodium chloride, and the mixture is extracted 6 times with chloroform. The extract is dried with magnesium sulfate, chromatographed on a column of silica gel and eluted with ethyl acetate to give 1.37 g (74.1% yield) of the objective compound.
m.p. 101.degree.-102.degree. C.
NMR: .delta..sup.CDCl 3 3.71 (3H, s), 3.86 (3H, s), 3.90 (2H, bs), 6.05 (1H, s)
Reference example 22 (Part 1)
Preparation of isopropyl 5-amino-1-methylpyrazole-3-carboxylate
In the same manner as in Reference example 19. the titled compound can be prepared. (Yield: 72.9%)
m.p. 86.degree.-87.degree. C.
NMR: .delta..sup.CDCl 3 1.37 (6H, d), 3.72 (3H, s), 3.75 (2H, bs), 5.23 (1H, m)
Reference example 23 (Part 1)
Preparation of methyl 2-nitrobenzylidene acetate ##STR56##
To 40 ml of benzene are added 11.6 g (0.1 mol) of methyl acetoacetate 13, 15 g (0.1 mol) of 2-nitrobenzaldehyde 12, 3 ml of acetic acid, and 0.8 ml of piperidine, and the mixture is kept at room temperature for 3 days, after which is added 12 g (0.1 mol) of magnesium sulfate thereto. The reaction mixture is stirred for 4 days, and filtered. Benzene is distilled off, and the residue is recrystallized from ethanol to give 22.5 g (90.0% yield) of the objective compound 14 as colorless prisms.
m.p. 100.degree.-101.degree. C.
NMR: .delta..sup.CDCl 3 2.47 (3H, s), 3.60 (3H, s), 7.23-8.37 (4H, m)
EXAMPLE 1 (Part 2)
Preparation of 2-methoxyethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate 3 ##STR57##
In 6 ml of tert-butanol are dissolved 0.90 g (3.05 mMol.) of 2-methoxyethyl 2-nitrobenzylideneacetoacetate 1 and 0.50 g (3.05 mMol.) of 3-cyclopentyl-5-amino-1-methylpyrazole 2, and the solution is allowed to react at 80.degree. C. for 3 hours, then evaporated under reduced pressure. The resulting residue is crystallized from ether, filtered and washed with a small amount of ether to give the 1.15 g of the titled compound 3. This is recrystallized from ethanol to give 0.92 g of yellow prisms in 59.6% yield, mp. 196.degree.-198.degree. C.
Elementary Analysis: Calcd. (%) for C.sub.23 H.sub.28 N.sub.4 O.sub.5 : C, 62.71; H, 6.41; N, 12.72. Found (%): C, 62.69; H, 6.20; N, 12.82. IR(Nujol) .nu. max: 3260(NH), 1690(C=O), 1360(NO.sub.2) cm.sup.-1. NMR(CDCl.sub.3) .delta. ppm: 0.97-2.03 (8H, m), 2.33, 3.27, 3.63 (3H.times.3, s), 2.92 (1H, m), 3.51 (2H, m), 4.13 (2H, m), 5.92 (1H, s), 6.67 (1H, br, s), 7.00-7.73 (4H, m).
EXAMPLES 2-33 (Part 2) ##STR58## wherein R.sup.1, R.sup.2 and R.sup.3 each has the same meaning as defined above.
A solution of compounds (II') and (III) in a solvent is allowed to react in nitrogen atmosphere at room temperature or under heating and then evaporated. The residue is crystallized from ether, or chromatographed on silica gel to give the objective compound (I'). This is, if needed, purified by recrystallization.
The objective compounds of the present invention can, which are listed in the following Table 2 (Part 2), be prepared in the manner commonly described above. Details of the reaction conditions are summarized in Table 3 (Part 2). Additionally, recrystallization solvents, appearance (crystal form, color), molecular formula and the result by elemental analysis in each compound or the acid addition salt are summarized in Table 4 (Part 2); and the IR- and NMR-spectrum data are shown in Table 5 (Part 2).
TABLE 2__________________________________________________________________________ ##STR59## (I')Example Position YieldNo. R.sup.1 R.sup.2 R.sup.3 of NO.sub.2 (%)__________________________________________________________________________2 CH.sub.2 CH.sub.2 OCH.sub.3 CH.sub.3 ##STR60## 3 97.53 " " ##STR61## 2 72.14 " " ##STR62## " 51.5 ##STR63## " ##STR64## " 75.46.sup.a ##STR65## " " " 77.07.sup.a ##STR66## " " " 78.98 ##STR67## " " " 81.59.sup.b ##STR68## " " " 81.910.sup.a " " " 3 89.711.sup.a " " ##STR69## 2 81.712.sup.b CH.sub.2 CH.sub.2 SCH.sub.3 " ##STR70## " 31.513.sup.b ##STR71## " " " 42.314 ##STR72## " " " 60.715.sup.b ##STR73## " " " 54.716.sup.a (CH.sub.2).sub.4.CH.sub.3 " " " 72.817 ##STR74## " " " 67.218.sup.a ##STR75## CH.sub.3 ##STR76## 2 76.019.sup.a ##STR77## " " " 74.820 ##STR78## " " 3 96.221.sup.a ##STR79## " " " 75.922.sup.a ##STR80## " " 2 71.423.sup.a ##STR81## " " " 77.524.sup.a ##STR82## " " " 77.825.sup.a ##STR83## " " " 72.826.sup.a ##STR84## " " " 76.827.sup.a ##STR85## " " " 67.028.sup.a ##STR86## " " " 64.329.sup.a ##STR87## " " 3 73.230.sup.a ##STR88## " " " 56.631.sup.a ##STR89## " " " 58.232.sup.a ##STR90## " " " 70.833.sup.a ##STR91## " " " 67.8__________________________________________________________________________ .sup.a Hydrochloride .sup.b Oxalate
TABLE 3__________________________________________________________________________ ##STR92## Amount used g (mmol.) Reaction ReactionExample No. Compd. (II') Compd. (III) Solvent (ml) Temp. (.degree.C.) Time (hrs.)__________________________________________________________________________2 0.88(3.01) 0.50(3.05) t-butanol (5) 80 33 0.88(3.01) 0.54(3.01) t-butanol (6) 80 34 0.88(3.01) 0.54(3.01) i-propanol (2) 70 725 0.67(2.0) 0.33(2.0) i-propanol (2) 80 156 0.57(1.64) 0.27(1.64) i-propanol (2) 80 247 1.04(2.87) 0.47(2.87) i-propanol (10) 80 208 0.64(2.0) 0.33(2.0) i-propanol (2) 80 249 0.71(2.0) 0.33(2.0) i-propanol (2) 80 2410 1.00(2.81) 0.47(2.87) i-propanol (10) 80 311 0.90(2.53) 0.45(2.53) i-propanol (9) 80 2012 0.62(2.0) 0.33(2.0) i-propanol (2) 80 2413 0.64(2.0) 0.33(2.0) i-propanol (4) 80 1814 2.01(5.08) 0.84(5.09) i-propanol (5) 80 1715 1.01(2.46) 0.41(2.48) i-propanol (25) 80 1916 0.89(2.92) 0.48(2.92) i-propanol (9) 80 1917 0.68(2.0) 0.33(2.0) i-propanol (2) 80 1618 0.95(2.54) 0.42(2.54) i-propanol (10) 80 2019 1.13(2.82) 0.47(2.82) i-propanol (10) 80 2020 3.39(9.19) 1.52(9.19) t-butanol (10) 80 221 4.09(10.9) 1.81(10.9) t-butanol (15) 80 322 1.0(2.7) 0.45(2.7) t-butanol (5) 80 1623 0.92(2.72) 0.45(2.7) i-propanol (5) 80 2024 1.08(2.96) 0.49(2.96) i-propanol (5) 80 2025 1.05(3.15) 0.52(3.15) i-propanol (5) 80 2026 1.33(4.0) 0.66(4.0) t-butanol (10) 80 2027 1.02(3.34) 0.55(3.34) i-propanol (5) 80 2028 1.01(3.19) 0.53(3.19) i-propanol (5) 80 1929 1.07(2.86) 0.47(2.86) i-propanol (8) 80 2.530 1.00(2.51) 0.42(2.51) i-propanol (6) 80 331 2.00(4.9) 0.81(4.9) i-propanol (10) 80 2432 1.67(4.0) 0.66(4.0) i-propanol (10) 70 4833 1.22(3.0) 0.50(3.0) i-propanol (10) 70 48__________________________________________________________________________
TABLE 4__________________________________________________________________________ ##STR93## (I') Solvent Elementary Analysis (%)Example Appear-.sup.c for Molecular Calcd. FoundNo. ance Recrystallization m.p. (.degree.C.) Formula C H N C H N__________________________________________________________________________2.sup.a YP ethanol 167-173 C.sub.23 H.sub.29 ClN.sub.4 O.sub.5 57.92 6.13 11.75 57.84 6.18 11.653 YP ethanol 200-202 C.sub.24 H.sub.30 N.sub.4 O.sub.5 63.42 6.65 12.33 63.26 6.41 12.364 YN i-propyl ether 148-149 C.sub.24 H.sub.30 N.sub.4 O.sub.5 63.42 6.65 12.33 63.37 6.57 12.395 YP i-propyl ether 101-103 C.sub.26 H.sub.34 N.sub.4 O.sub.5 64.71 7.10 11.61 64.89 7.07 11.536.sup.a YP acetone 119-121.sup.a C.sub.27 H.sub.35 ClN.sub.4 O.sub.5.H.sub.2 59.06 6.79 10.20 59.15 6.55 10.087.sup.a YP acetone/ether 115-118.sup.a C.sub.28 H.sub.37 ClN.sub.4 O.sub.5 61.70 6.84 10.28 61.61 6.85 10.018 YP i-propanol 153-154 C.sub.25 H.sub.30 N.sub.4 O.sub.5 64.36 6.48 12.01 64.25 6.47 11.909.sup.b YP methylene chloride 171-173.sup.b C.sub.30 H.sub.32 N.sub.4 O.sub.9.H.sub.2 59.01 5.61 9.18 58.59 5.20 8.7410.sup.a P acetone 145-150.sup.a C.sub.28 H.sub.31 ClN.sub.4 O.sub.5 62.39 5.80 10.39 62.17 5.81 10.3311.sup.a YP acetone 125-130.sup.a C.sub.29 H.sub.33 ClN.sub.4 O.sub.5.H.sub.2 61.00 6.18 9.81 60.59 5.99 9.6612 YP i-propyl ether 124-126.sup.b C.sub.25 H.sub.30 N.sub.4 O.sub.8 S.1/2H.sub.2 O 54.04 5.62 10.08 54.28 5.38 10.0513.sup.b YP acetone 134-136.sup.b C.sub.27 H.sub.35 N.sub.5 O.sub.8.2H.sub.2 54.63 6.62 11.80 54.73 6.21 11.8714 YA -- -- C.sub.33 H.sub.37 N.sub.5 O.sub.815.sup.b YP methanol 180- 182.sup.b C.sub.34 H.sub.39 N.sub.5 O.sub.8.1/2H.sub.2 62.37 6.16 10.70 62.23 6.15 10.7116.sup.a YP ethyl acetate 110-113.sup.a C.sub.24 H.sub.33 ClN.sub.4 O.sub.4 60.44 6.97 11.75 60.01 6.97 11.4517.sup.b YN acetone 180-182.sup.b C.sub.30 H.sub.32 N.sub.4 O.sub.8.H.sub.2 60.60 5.76 9.42 60.60 5.44 9.3318.sup.a YP acetone 166-170.sup.a C.sub.28 H.sub.30 Cl.sub.2 N.sub.4 O.sub.4 60.33 5.42 10.05 60.10 5.52 9.8519.sup.a YP acetone 128-130.sup.a C.sub.30 H.sub.35 ClN.sub.4 O.sub.6.1/2H.sub.2 O 60.86 6.13 9.46 61.02 6.20 9.1220 YA -- -- C.sub.29 H.sub.32 N.sub.4 O.sub.5 67.42 6.24 10.8521 Pl acetone 164-170.sup.a C.sub.30 H.sub.41 ClN.sub.4 O.sub.4 64.68 7.42 10.06 64.61 7.41 9.9822.sup.a YN acetone 125-127.sup.a C.sub.28 H.sub.31 ClN.sub.4 O.sub.4 60.58 5.63 10.09 60.60 5.91 9.6323.sup.a YP acetone 152-155.sup.a C.sub.25 H.sub.33 ClN.sub.4 O.sub.4 S 57.63 6.38 10.75 57.43 6.43 10.6324.sup.a YP acetone 148-150.sup. a C.sub.27 H.sub.35 ClN.sub.4 O.sub.4 S 59.28 6.45 10.24 59.30 6.66 10.2125.sup.a YP acetone 145-150.sup.a C.sub.27 H.sub.35 ClN.sub.4 O.sub.4 62.97 6.85 10.88 62.64 6.97 10.8026.sup.a YP ethanol 179-184.sup.a C.sub.27 H.sub.35 ClN.sub.4 O.sub.4 62.96 6.85 10.88 62.78 6.81 10.7327.sup.a YP acetone 141-150.sup.a C.sub.25 H.sub.31 ClN.sub.4 O.sub.4 61.66 6.42 11.50 61.21 6.31 11.3028.sup.a YP acetone 150-155.sup.a C.sub.26 H.sub.33 ClN.sub.4 O.sub.4 62.33 6.64 11.18 62.10 6.46 11.2529.sup.a YP " 137-140.sup.a C.sub.28 H.sub.30 ClN.sub.4 O.sub.4 60.32 5.42 10.05 60.20 5.65 9.6830.sup.a YP ethanol 150-152.sup.a C.sub.30 H.sub.35 ClN.sub.4 O.sub.6 61.80 6.05 9.61 61.77 5.95 9.5431.sup.a YN " 124-126.sup.a C.sub.28 H.sub.29 ClN.sub.4 O.sub.4 1/3H.sub.2 O 56.23 5.02 9.36 56.66 5.42 8.9032.sup.a YP " 197-200.sup.a C.sub.28 H.sub.30 BrClN.sub.4 O.sub.4 55.82 4.98 9.30 55.62 4.90 9.3033.sup.a CP " 147-149.sup.a C.sub. 29 H.sub.30 ClF.sub.3 N.sub.4 O.sub.4 58.88 5.07 9.47 58.78 4.96 9.40__________________________________________________________________________ .sup.a Hydrochloride, .sup.b Oxalate .sup.c YP = Yellow prism; YN = Yellow Needles; YA = Yellow Amorphous; P = Colorless Prisms; Pl = Colorless Plates
TABLE 5__________________________________________________________________________Example IR (.nu..sub.max.sup.cm.sup.-1)No. NH CO NO.sub.2 NMR (.delta..sub.ppm.sup.CDCl.sbsp.3)*__________________________________________________________________________2 3440 1690 1350 1.25-1.92(8H, m), 2.38, 3.32, 3.63(3H .times. 3, s), 2.58(1H, m), 3.51(2H, m), 4.14(2H, m), 5.25(1H, s), 7.13-8.08(5H, m)3 3270 1695 1360 0.77-2.32(10H, m), 2.35, 3.28, 3.65(3H .times. 3, s), 2.50(1H, m), 3.50(2H, m), 4.13(2H, m), 5.95(1H, s), 7.00(1H, br.s), 7.13-7.80(4H, m)4 3270 1698 1378 0.83-1.77(9H, m), 2.27-2.48(2H, m), 2.38, 3.30, 3.67(3H .times. 3, s), 3.45(2H, t), 4.10(2H, t), 5.90(1H, s), 6.25(1H, br.s), 7.07-7.77(4H, m)5 3240 1692 1355 0.95-2.03(10H, m), 1.06(6H, d), 2.37, 3.67(3H .times. 2, s), 2.89(1H, m), 3.33(3H, m), 4.04(2H, t), 5.90(1H, s), 6.68(1H, br.s), 7.10-7.77(4H, m)6 3430 1690 1355 1.01-2.13(16H, m), 2.36, 3.66(3H .times. 2, s), 2.58-3.20(1H, m), 3.28-4.33(3H, m), 5.91(1H, s), 6.26(1H, br.s), 7.03-7.77(4H, m)7 2570- 1685 1365.sup.a 1.01-3.37(20H, m), 2.33, 3.65(3H .times. 2, s), 3.50(2H, t), 3.80-4.33(2H, m), 5.92(1H, s), 2690 6.90(1H, br.s), 7.07-7.73(4H, m)8 3250 1688 1360 0.93-2.17(12H, m), 2.33, 3.68(3H .times. 2, s), 2.67-3.13(1H, m), 3.47-4.27(5H, m), 5.93(1H, s), 7.00-7.83(5H, m)9 2300 1730 1378.sup.b 1.05-1.93(8H, m), 2.33, 3.63(3H .times. 2, s), 2.63-3.12(1H, m), 3.77-4.47(4H, m), 1700 5.95(1H, s), 6.70-7.78(4H, m)10 2530 1700 1360.sup.a 1.22-2.80(9H, m), 2.42, 3.67(3H .times. 2, s), 4.07, 4.37(2H .times. 2, m), 5.27(1H, s), 7.05(1H, br.s), 7.05-8.08(9H, m)11 2530- 1679 1357.sup.a 0.83-2.77(11H, m), 2.35, 3.63(3H .times. 2, s), 3.92-4.08(2H, m), 4.17-4.50(2H, m), 2650 3.91(1H, s), 6.90(1H, br.s), 6.75-7.70(9H, m)12 2300 1702 1378.sup.b 1.00-3.20(11H, m), 2.07, 2.35, 3.65(3H .times. 3, s), 3.83-4.33(2H, m), 5.90(1H, s), 7.00-8.03(4H, m)13 3430 1690 1355 1.10-2.58(11H, m), 2.22(6H, s), 2.38, 3.70(3H .times. 2, s), 2.72-3.23(2H, m), 3.57-4.30(2H, m), 5.91(1H, s), 6.95- 7.81(4H, m)14 3430 1685 1350 1.08-3.03(15H, m), 2.30, 3.58(3H .times. 2, s), 3.50(2H, s), 4.87-5.20(1H, m), 6.02(1H, s), 7.01-7.85(10H, m)15 3430 1680 1350 1.12-3.00(17H, m), 2.32, 3.63(3H .times. 2, s), 3.42(2H, s), 4.43-4.90(1H, m), 6.21 (1H, s), 7.10-7.86(9H, m)16 2570- 1697 1357.sup.a 0.77-3.16(18H, m), 2.34, 3.63(3H .times. 2, s), 3.75-4.07(2H, m), 5.92(1H, s), 6.98 2675 (1H, br.s), 7.07-7.73(4H, m)17 2300 1733 1375.sup.b 1.10-2.00(8H, m), 2.27, 3.62(3H .times. 2, s), 2.57-3.27(3H, m), 3.87-4.50(2H, m), 1700 5.93(1H, s), 7.00-8.27(9H, m)18 2370 1705 1360.sup.a 1.10-3.20(9H, m), 2.29, 3.67(3H .times. 2, s), 2.73(2H, t), 3.90-4.37(2H, m), 5.88(1H, s), 6.74(1H, br.s), 6.99-7.73(8H, m)19 2360 1699 1348.sup.a 1.11-3.18(9H, m), 3.30, 3.64(3H .times. 2, s), 2.70(2H, t), 3.82(6H, s), 3.93-4.29(2H, m), 5.90(1H, s), 6.72(3H, s), 6.83(1H, br.s), 7.07-7.73(4H, m)20 3430 1690 1350 1.10-2.77(9H, m), 2.37, 3.20, 3.24, 3.66(3H .times. 4, s), 3.97-4.50(3H, m), 5.22(1H, s) 6.92(1H, br.s), 7.12-8.08(9H, m)21 3425 1675 1340 0.37-2.70(27H, m), 4.67(1H, m), 2.38, 2.45, 3.66(3H .times. 3, s), 5.20, 5.27(1H, 2s), 6.80, 6.93(1H, 2 br.s), 7.20-8.12(4H, m)22 2700 1694 1352.sup.a 1.0-1.93(8H, m), 2.3(3H, s), 2.67-3.23(3H, m), 3.6(3H, s), 3.83-4.33(2H, m), 5.85(1H, s) 6.87-8.03(9H, m)23 2670 1705 1363.sup.a 1.0-3.20(9H, m), 1.23(3H .times. 2, d), 2.37, 3.67(3H .times. 2, s), 2.56(2H, t), 2.93(1H, sep), 3.83-4.30(2H, m), 5.90(1H, s), 7.0(1H, br.s), 7.12-7.77(4H, m)24 2480 1701 1359.sup.a 1.03-3.30(18H, m), 2.38, 3.68(3H .times. 2, s), 2.58(2H, t), 3.87-4.33(2H, m), 5.91(1H, s), 6.88(1H, br.s), 7.13-7.77(4H, m)25 2520 1700 1358.sup.a 0.77-3.10(20H, m), 2.33, 3.62(3H .times. 2, s), 3.73-4.17(2H, m), 5.90(1H, s), 6.83 (1H, br.s), 7.07-7.73(4H, m)26 2450 1701 1355.sup.a 0.53-2.30(19H, m), 2.38(3H, s), 2.71-3.20(1H, m), 3.50-4.28(2H, m), 3.68(3H, s), 5.94(1H, s), 6.52(1H, br.s), 7.10-7.81(4H, m)27 2530 1683 1358 1.03-3.17(17H, m), 2.32, 3.62(3H .times. 2, s), 5.03(1H, m), 6.03(1H, s), 6.90(1H, br.s), 7.10-7.82(4H, m)28 2525 1702 1355.sup.a 0.9-3.13(19H, m), 2.36, 3.63(3H .times. 2, s), 4.62(1H, m), 6.03(1H, s), 6.82(1H, br.s), 7.10-7.84(4H, m)29 3420 1685 1350 1.15-2.0(8H, m), 2.35(3H, s), 2.60(1H, m), 2.70-2.93(2H, m), 3.66(3H, s), 4.04-4.37 3270 (2H, m), 5.12(1H, s), 6.35(1H, s), 6.99-8.01(8H, m)30 3420 1685 1350 1.15-1.72(8H, m), 2.36(3H, s), 2.58(1H, m), 2.83(2H, m), 3.67(3H, s), 3.85(6H, s), 3280 4.24(2H, m), 5.20(1H, s), 6.63-8.05(8H, m)31 2670 1700 1375.sup.a 1.07-3.32(9H, m), 2.30(3H, s), 2.75(2H, t), 3.67(3H, s), 4.17(2H, t), 5.90(1H, s), 6.83-7.80(4H, m), 8.27(1H, s)32 2380 1713 1355.sup.a 1.07-2.0(8H, m), 2.27(3H, s), 2.72(2H, t), 2.72-3.18(1H, m), 3.62(3H, s), 5.87(1H, s), 6.83-7.83(8H, m)33 2680 1715 1338.sup.a 1.07-2.13(8H, m), 2.25(3H, s), 2.55-3.20(1H, m), 2.83(2H, t), 3.62(3H, s), 4.17(2H, t), 5.87(1H, s), 6.97-7.83(8H, m)__________________________________________________________________________ .sup.a Hydrochloride, .sup.b Oxalate *Data of NMR are shown as those on free bases.
EXAMPLE 34 (Part 2)
Components for tablet
______________________________________Phenethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate 10 mgCorn starch 50 mgGelatin 7.5 mgAvicel 25 mgMagnesium stearate 2.5 mgTotal 95 mg______________________________________
These substances are formulated into a tablet.
PREPARATION 1 (Part 2)
Preparation of 2-methoxyethyl 2-nitrobenzylideneacetoacetate 6 ##STR94##
A solution of 4.80 g (30.0 mMol) of methoxyethylacetoacetate 5, 4.53 g (30.0 mMol) of 2-nitrobenzaldehyde 4, 1.0 ml of acetic acid and 0.3 ml of piperidine in 25 ml of benzene is stirred at room temperature for 17 hours, and the mixture is refluxed for 2 hours in a condition of azeotropic distillation. The reaction mixture is washed with water, dried over magnesium sulfate, filtered, and evaporated. The residue is chromatographed on silica gel for purification to give 7.93 g (90.2% yield) of the titled compound 6 as an yellow oil [from the eluate with dichloromethane/ethyl acetate (95/5)]. NMR(CDCl.sub.3) .delta. ppm: 2.23, 2.48(3H, 2s), 3.17-3.80(2H, m), 3.22, 3.40(3H, 2s), 4.08-4.53(2H, m), 7.33-8.33(5H, m).
PREPARATIONs 2-30 (Part 2) ##STR95## wherein R.sup.1 has the same meaning as defined above.
A solution of the compound (XI') and a compound (IX) in a solvent is allowed to react in the presence of an organic base at room temperature or under heating, and then refluxed if needed. The reaction mixture is washed with water, dried, filtered, and evaporated. According to the requisition, the resulting residue is subjected to recrystallization or chromatography on silica gel in order to purify.
Each of the compounds (II') listed in the following Table 6 can be prepared in the above-depicted manner. The yield for a compound (II') is listed in Table 6 (Part 2). The process for production of the starting substances (IX) is depicted over the top of Table 6 (Part 2), the yield of which is also listed in Table 6 (Part 2). In addition, the detailes of the reaction conditions for the above reaction (Preparations 2-25 as Part 2) are summarized in Table 7 (Part 2). Data of melting point and NMR spectrum on each of the compounds (II') and the starting substances (IX) are summarized in Table 5 (Part 2).
TABLE 6__________________________________________________________________________ ##STR96## ##STR97## Yield of Position Yield ofPrepn. No. R' (IX) (%) of NO.sub.2 (II') (%)__________________________________________________________________________2 CH.sub.2 CH.sub.2 OCH.sub.3 Compd. 3 88.4 marketed ##STR98## 72.7 2 50.74 ##STR99## 68.1 " 84.05 ##STR100## 94.1 " 91.66 ##STR101## 74.6 " 79.47 ##STR102## 86.5 " 94.48 " " 3 75.99 CH.sub.2 CH.sub.2 SCH.sub.3 25.1 2 86.710 ##STR103## 79.0 " 53.111** ##STR104## 95.0 " 84.612 ##STR105## 81.0 " 62.213 (CH.sub.2).sub.4 CH.sub.3 77.0 " 89.014 ##STR106## 89.3 " 88.215 ##STR107## 95.8 " 96.016 ##STR108## 92.9 2 96.817 ##STR109## 89.6 3 87.518* ##STR110## 89.4 3 71.219 ##STR111## 99.6 2 84.220 ##STR112## 96.6 " 93.221 ##STR113## 92.1 " 92.422 ##STR114## 96.6 " 97.423 ##STR115## 94.5 " 85.524 ##STR116## 92.9 " 97.725 ##STR117## 93.5 " 97.326 ##STR118## vide supra 3 98.027 ##STR119## vide supra 3 90.428 ##STR120## 90.6 2 93.129 ##STR121## 98.1 2 76.530 ##STR122## 97.2 2 54.1__________________________________________________________________________ *(IX)-18: Disclosed in F. Korte, F. Wuesten, Liebigs Ann., 647, 18 (1961) **Material for (IX)11, ##STR123## Disclosed in E. Jaeger, J. H. Biel, J. Org. Chem, 30, 740 (1965) Ph = Phenyl
TABLE 7__________________________________________________________________________ ##STR124##Prepn. Amount used g (mmol.) Reaction ReactionNo. Compd.(XI') Compd.(IX) Solvent (ml) Temp. (.degree.C.) Time (hrs.)__________________________________________________________________________2 4.53(30.0) 4.80(30.0) benzene (25) r.t. 21 P(0.1), AcOH(0.3)3 2.04(13.5) 2.72(13.4) benzene (5) r.t. 100 P(0.1), AcOH(0.2) reflux 14 0.30(1.96) 0.42(1.96) benzene (2) r.t. 72 P(0.004), AcOH(0.01) reflux 25 1.51(10.0) 2.28(10.0) benzene (5) r.t. 72 P(0.05), AcOH(0.2) reflux 36 4.53(30.0) 5.58(30.0) benzene (10) r.t. 72 P(0.1), AcOH(0.4)7 4.76(31.5) 7.0(31.5) benzene (10) 40 100 P(0.05), AcOH(0.2) reflux 28 " " " " "9 3.78(25.0) 4.4(25.0) benzene (5) r.t. 72 P(0.1), AcOH(0.4)10 4.53(30.0) 5.62(30.0) benzene (10) r.t. 72 P(0.1), AcOH(0.4)11 0.91(6.01) 1.57(6.01) benzene (3) r.t. 48 P(0.01), AcOH(0.04) reflux 112 1.14(7.57) 2.08(7.57) benzene (4) reflux 4 P(0.01), AcOH(0.04)13 6.14(40.6) 7.00(40.6) benzene (10) 40 100 P(0.05), AcOH(0.2) reflux 214 4.53(30.0) 6.18(30.0) benzene (10) r.t. 72 P(0.1), AcOH(0.4) reflux 315 1.51(10.0) 2.41(10.0) benzene (5) r.t. 72 P(0.05), AcOH(0.2) reflux 216 1.51(10.0) 2.66(10.0) benzene (5) r.t. 72 P(0.05), AcOH(0.2) reflux 317 1.62(10.7) 2.53(10.7) benzene (2) r.t. 72 P(0.02), AcOH(0.1) reflux 718 4.0(26.5) 6.38(26.5) benzne (10) r.t. 72 P(0.05), AcOH(0.2) reflux 719 3.0(20.0) 4.76(20.0) benzne (20) r.t. 16 P(0.1), AcOH(0.2) reflux 220 4.89(32.3) 6.6(32.3) benzene (20) r.t. 16 P(0.15), AcOH(0.3) reflux 121 4.34(29.1) 6.7(29.1) benzene (20) r.t. 16 P(0.15), AcOH(0.3) reflux 122 3.58(23.7) 4.7(23.7) benzene (20) r.t. 16 P(0.3), AcOH(0.6) reflux 123 4.53(30.0) 5.95(30.0) benzene (10) r.t. 16 P(0.3), AcOH(0.6) reflux 124 2.66(17.6) 3.0(17.6) benzene (6) r.t. 16 P(0.05), AcOH(0.2) reflux 225 2.46(16.3) 3.0(16.3) benzene (6) r.t. 16 P(0.05), AcOH(0.2) reflux 226 2.78(18.38) 4.42(18.37) benzene (9) r.t. 96 P(0.036), AcOH(0.1) reflux 227 1.0(6.64) 1.77(6.64) benzene (4) r.t. 96 P(0.013), AcOH(0.038) reflux 228 1.51(10.0) 2.75(10.0) benzene (10) r.t. 20 P(0.1), AcOH(1.0) reflux 229 1.51(10.0) 2.85(10.0) benzene (10) r.t. 20 P(0.1), AcOH(1.0) reflux 230 1.51(10.0) 2.74(10.0) benzene (10) r.t. 20 P(0.1), AcOH(1.0) reflux 2__________________________________________________________________________ *P: Piperidine, AcOH: Acetic acid, r.t.: room temperature
TABLE 8__________________________________________________________________________Prepn. Boiling PointNo. .degree.C. (mmHg) NMR (.delta..sub.ppm.sup.COCl.sbsp.3)__________________________________________________________________________CH.sub.3 COCH.sub.2 COOR.sup.1 (IX)(IX)-3 90-91 (0.6) 1.12(6H,d), 1.93(2H,m), 2.55(3H,s), 3.33-4.02(3H,m), 3.45(2H,s), 4.23(2H,t)4 96-100 (0.1) 1.15-1.90(8H,m), 2.27(3H,s), 3.36-4.47(5H,m), 3.47(2H,s)5 118-120 (0.4) 1.15-2.07(10H,m), 2.26(3H,s), 3.25(1H,m), 3.45(2H,s), 3.63, 4.26(2H .times. 2,t)6 95-100 (0.9) 1.33-2.17(4H,m), 2.27(3H,s), 3.50(2H,s), 3.53-4.33(4H,m)7,8 140-143 (0.7) 2.20(3H,s), 3.43(2H,s), 4.03-4.60(4H,m), 6.73-7.43(5H,m)9 160-162 (25) 2.13, 2.27(3H .times. 2,s), 2.72(2H,t), 3.45(2H,s), 4.28(2H,t)10 138-141 (23) 1.40-2.98(4H,m), 2.20(6H,s), 2.23(3H,s), 3.45(2H,s), 4.18(2H,t)11 oil 1.63-2.98(6H,m), 2.23(3H,s), 3.42, 3.63(2H .times. 2,s), 5.24(1H,m), 7.31(5H,s)12 oil 1.48-2.82(8H,m), 2.23(3H,s), 3.40, 3.47(2H .times. 2,s), 4.83(1H,m), 7.27(5H,s)(IX)-13 106-111 (8) 0.67-2.17(9H,m), 2.27(3H,s), 3.45(2H,s), 4.13(2H,t)14 100-115 (0.8) 2.15(3H,s), 2.93(2H,t), 3.38(2H,s), 4.33(2H,t), 7.23(5H,s)15 155-158 (0.7) 2.18(3H,s), 2.90(2H,t), 3.39(2H,s), 4.30(2H,t), 7.10, 7.26(2H .times. 2,d)16 182-185 (0.8) 2.19, 3.82, 3.85(3H .times. 3,s), 2.88(2H,t), 3.40(2H,s), 4.42(2H,t), 6.75(3H,m)17 oil 2.23, 3.28(3H .times. 2,s), 3.46(2H,s), 4.37(3H,m), 7.28(5H,s)18 95-101 (0.3) 0.62-2.35(18H,m), 4.73(1H,m), 2.35(3H,s), 3.42(2H,s)19 oil 2.18(3H,s), 3.08(2H,t), 3.33(3H,s), 4.20(2H,t), 6.97-7.37(5H,m)20 oil 1.25(3H .times. 2,d), 2.27(3H,s), 2.75(2H,t), 3.02(1H,q), 3.43(2H,s), 4.23(2H,t)21 oil 1.13-2.23(8H,m), 2.47(3H,s), 2.73(2H,t), 2.93-3.27(1H,m), 3.43(2H,s), 4.23(2H,t)22 oil 1.03-2.0(11H,m), 2.23(3H,s), 3.4(2H,s), 4.3(2H,t)(IX)-23 oil 0.67-2.03(11H,m), 2.2(3H,s), 3.40(2H,s), 3.95(2H,d)24 103-106 (6) 0.96-2.10(8H,m), 2.28(3H,s), 3.43(2H,s), 5.25(1H,m)25 116-119 (6) 0.97-2.04(10H,m), 2.25(3H,s), 3.42(2H,s), 4.82(1H,m)(IX)-26 vide supra vide supra27 vide supra vide supra28 oil 2.18(3H,s), 2.90(2H,t), 3.40(2H,s), 4.30(2H,t), 6.90-7.43(3H,m)29 oil 2.18(3H,s), 2.88(2H,t), 3.40(2H,s), 4.32(2H,t), 6.93-7.53(4H,m)30 oil 2.20(3H,s), 3.02(2H,t), 3.42(2H,s), 4.37(2H,t), 7.43(4H,s) ##STR125## (II')(II)-2 mp. 43-45.degree. C. 2.43, 3.28(3H .times. 2,s), 3.50-3.75(2H,m), 4.30-4.55(2H,m), 7.33-8.33(5H,m)3 oil 1.08(6H,d), 1.52-2.07(2H,m), 2.47(3H,s), 3.12-4.48(5H,m), 7.27-8.25(5H,m)4 oil 1.07-1.84(8H,m), 2.23, 2.49(3H,2s), 3.17-4.47(5H,m), 7.36-8.31(5H,m)5 oil 0.77-2.10(10H,m), 2.22, 2.47(3H,2s), 3.17(1H,m), 3.43, 3.72(2H,2t), 4.17, 4.42 (2H,2t), 7.27-8.30(5H,m)6 oil 1.03-2.17(4H,m), 2.23, 2.47(3H,2s), 3.47-4.37(5H,m), 7.23-8.36(5H,m)7 oil 2.18, 2.42(3H,2s), 3.70-4.70(4H,m), 6.60-8.23(10H,m)8 mp.127-131.degree. C. 2.44(3H,s), 4.18, 4.65(2H .times. 2,t), 6.72-8.33(10H,m)(II')-9 oil 2.00, 2.17(3H,2s), 2.22, 2.48(3H,2s), 2.45, 2.83(2H,2t), 4.17, 4.45(2H,2t), 7.20-8.33(5H,m)10 oil 1.38-2.33(4H,m), 2.13(6H,s), 2.47(3H,s), 4.05, 4.33(2H,2t), 7.25-8.33(5H,m)11 oil 1.36-3.06(6H,m), 2.20, 2.45(3H,2s), 3.50, 3.65(2H,2s), 4.99-5.48(1H,m), 7.16-8.27(10H,m)12 oil 1.09-2.85(8H,m), 2.18, 2.46(3H,2s), 3.39, 3.51(2H,2s), 4.62-5.25(1H,m), 7.07-8.41(10H,m)13 oil 0.63-2.02(9H,m), 2.20, 2.47(3H,2s), 3.98, 4.27(2H,2t), 7.35-8.27(5H,m)14 oil 2.12, 2.40(3H,2s), 2.68, 3.00(2H,2t), 4.22, 4.47(2H,2t), 6.83-8.23(10H,m)15 oil 2.10, 2.43(3H,2s), 2.68, 3.00(2H,2t), 4.20, 4.48(2H,2t), 6.87-8.30(9H,m)16 oil 2.08, 2.40(3H,2s), 2.62, 2.93(2H,2t), 3.78, 3.83, 3.85(6H,3s), 4.18, 4.45(2H,2t) 6.43-8.30(8H,m)(II')-17 oil 2.33, 2.41(3H,2s), 3.20, 3.31(3H,2s), 4.43(3H,m), 7.28-8.27(10H,m)18 oil 0.48-2.48(18H,m), 4.90(1H,m), 2.38(3H,s), 7.38-8.35(5H,m)19 oil 2.17, 2.42(3H,s), 2.82, 3.18(2H,t), 4.12, 4.37(2H,t), 7.0-8.23(10H,m)20 oil 1.2, 1.32(3H .times. 2,d), 2.23, 2.5(3H,s), 2.5, 2.87(2H,t), 2.77-3.17(1H,m), 4.15, 4.42(2H,t), 7.23-8.33(5H,m)21 oil 1.07-2.11(8H,m), 2.23, 2.48(3H,s), 2.52, 2.87(2H,t), 2.73-3.33(1H,m), 4.17 4.4(2H,t), 7.27-8.37(5H,m)22 oil 0.67-2.0(11H,m), 2.2, 2.45(3H,s), 3.98, 4.27(2H,t), 7.23-8.3(5H,m)23 oil 0.5-2.0(11H,m), 2.2, 2.43(3H,s), 3.8, 4.07(2H,d), 7.27-8.33(5H,m)24 oil 1.17-2.07(8H,m), 2.20, 2.47(3H,s), 5.0-5.50(1H,m), 7.30-8.29(4H,m)25 oil 0.83- 2.17(10H,m), 2.22, 2.47(3H,s), 4.57-5.17(1H,m), 7.30-8.28(5H,m)(II')-26 oil 2.25, 2.37(3H,s), 2.80-3.09(2H,m), 4.35-4.57(2H,m), 6.91-8.29(9H,m)27 oil 2.27, 2.38(3H,s), 2.78-3.04(2H,m), 3.77, 3.80(3H,s), 3.83, 3.87(3H), 4.35-4.57(2H,m) 6.59-8.28(8H,m)28 oil 2.12, 2.43(3H,s), 2.67, 2.97(2H,t), 4.20, 4.45(2H,t), 6.72-8.27(7H,m)29 oil 2.12, 2.40(3H,s), 2.63, 2.95(2H,t), 4.18, 4.43(2H,t), 6.73-8.27(9H,m)30 oil 2.10, 2.40(3H,s), 2.77, 3.08(2H,t), 4.23, 4.48(2H,t), 7.10-8.27(9H,m)__________________________________________________________________________
PREPARATION 31 (Part 2)
(i) Preparation of 3-cyclopentylcarbonylacetonitrile 9 ##STR126##
To 20 ml of tetrahydrofuran is added 15.6 ml (26 mMol) of butyl lithium in an atmosphere at -78.degree. C., and 1.3 g (32 mMol) of acetonitrile is dropwisely added to the mixture over the period of 40 minutes. Two hours later, 3.43 g (25.9 mMol) of cyclopentylcarbonyl chloride 7 is further added dropwisely over a period of 40 minutes. The reaction mixture is, after being stirred for 2 hours, neutralized with 10% hydrochloric acid and extracted with ether. The extract solution is dried over magnesium sulfate, filtered, and then evaporated. The resulting residue is subjected to column chromatography to give 2.91 g (80.8% yield) of the titled compound 9 as an oil (from the chloroform layer).
NMR(CDCl.sub.3) .delta. ppm: 1.43-2.2 (8H, m), 2.7-3.33 (1H, m), 3.53 (2H, s).
(ii) Preparation of 5-amino-3-cyclopentyl-1-methylpyrazole 11 ##STR127##
To a solution of 13.21 g (96.3 mMol) of 3-cyclopentylcarbonylacetonitrile 9 in 10 ml of dioxane is added 4.44 g (96.3 mMol) of methylhydrazine 10 under ice-cooling, and the mixture is stirred at room temperature for 17 hours. The reaction mixture is evaporated. The resulting residue is recrystallized from ethyl acetate/hexane (5/2) to give 12.9 g (80.8% yield) of the titled compound 11 as colorless needles, mp. 149.degree.-150.degree. C.
NMR(CDCl.sub.3) .delta. ppm: 1.33-2.20 (8H, m), 2.60-3.10 (1H, m), 3.57 (5H, s), 5.32 (1H, s).
PREPARATIONS 32 and 33 (Part 2) ##STR128## wherein R.sup.2 and R.sup.3 have the same meanings as defined above respectively.
A solution of compounds (VI) and (VII) in a solvent is allowed to react at room temperature, then evaporated, and the resulting residue is purified by recrystallization, if needed.
In the above-depicted manner, the compounds (III) can be prepared. Details of the reaction conditions are summarized in Table 9 (Part 2), and data such as yield, melting points, and NMR spectrum on the compounds are in Table 10 (Part 2).
TABLE 9__________________________________________________________________________ ##STR129## (III) ReactionPrepn. Amount used g(mmol.) Solvent TimeNo. R.sup.2 R.sup.3 Compd. (VI) Compd.(VII) (ml) (hrs.)__________________________________________________________________________32 CH.sub.3 ##STR130## 1.90(41.3) 6.05(40.0) ethanol (10) 2433 CH.sub.3 ##STR131## 1.43(31.0) 4.60(30.4) ethanol (8) 15__________________________________________________________________________
TABLE 10__________________________________________________________________________Prepn. Yield Melting PointNo. R.sup.2 R.sup.3 (%) (.degree.C.) NMR: .delta..sub.ppm.sup.CDCl.sbsp.3__________________________________________________________________________32 CH.sub.3 ##STR132## 71.7 172.about.174 0.90.about.2.77(11H, m), 3.43(2H, br, s), 3.57(3H, s), 5.32(1H, s)33 CH.sub.3 ##STR133## 64.9 106.about.107 0.93.about.2.32(9H, m), 2.47(2H, m), 3.51(3H, s), 3.60(2H, br, s), 5.28(1H,__________________________________________________________________________ s)
Claims
  • 1. A 4,7-dihydropyrazolo[3,4-b]-pyridine derivative represented by the formula: ##STR134## wherein R.sup.1 is (a) straight or branched chain C.sub.5 -C.sub.8 alkyl, (b) C.sub.4 -C.sub.6 cycloalkyl which may be substituted by lower alkyl, (c) C.sub.3 -C.sub.7 cycloalkyl (C.sub.1 -C.sub.4)alkyl, (d) C.sub.1 -C.sub.4 alkoxy-(C.sub.1 -C.sub.4)alkyl, (e) C.sub.4 -C.sub.7 cycloalkyloxy(C.sub.1 -C.sub.4)alkyl, (f) phenoxy(C.sub.1 -C.sub.4)alkyl, (g) C.sub.1 -C.sub.4 alkylthio(C.sub.1 -C.sub.4)alkyl, (h) C.sub.4 -C.sub.7 cycloalkylthio(C.sub.1 -C.sub.4)alkyl, (i) phenylthio(C.sub.1 -C.sub.4)alkyl, (j) C.sub.1 -C.sub.4 monalkylamino or C.sub.2 -C.sub.8 dialkylamino-substituted (C.sub.1 -C.sub.4)alkyl, (k) tetrahydrofuryl(C.sub.1 -C.sub.4)alkyl, (l) phenyl(C.sub.1 -C.sub.3)alkyl, which may have one or more substituents of halogen or C.sub.1 -C.sub.4 alkoxy, (m) N-benzylpyrrolidinyl, or (n) N-benzylpiperidinyl; R.sup.2 is C.sub.1 -C.sub.4 alkyl; and R.sup.3 is C.sub.4 -C.sub.6 cycloalkyl or C.sub.3 -C.sub.7 cycloalkyl(C.sub.1 -C.sub.4)alkyl; and the pharmaceutically acceptable acid addition salts thereof.
  • 2. A compound as claimed in claim 1 in which R' is a halogenphenyl (C.sub.1 -C.sub.3) alkyl.
  • 3. A compound claimed in claim 1, namely, cyclopentyloxyethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo-[3,4-b]pyridine-5-carboxylate.
  • 4. A compound claimed in claim 1, namely, methylthioethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate.
  • 5. A compound claimed in claim 1, namely, phenethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]-pyridine-5-carboxylate.
  • 6. A compound claimed in claim 1, namely, cyclopentylethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate.
  • 7. A compound claimed in claim 1, namely, (3-thienyl)ethyl 3-cyclopentyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate.
  • 8. A 4,7-dihydropyrazolo[3,4-b]pyridine derivative represented by the formula: ##STR135## wherein X and X.sup.1 each is hydrogen, nitro, or halogen which may be located at the position or positions 2, 3, and/or 6;
  • R.sup.1 is C.sub.1 -C.sub.4 alkyl; R.sup.2 is hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.4 -C.sub.6 cycloalkyl, or phenyl;
  • R.sup.3 is hydrogen, C.sub.1 -C.sub.8 straight or branched chain alkyl, C.sub.3 -C.sub.7 cycloalkyl which may be substituted by C.sub.1 -C.sub.3 alkyl, phenyl which may be substituted by chlorine, trifluoromethyl, cyano, methoxy, methoxycarbonyl or ethoxycarbonyl, C.sub.7 -C.sub.9 aralkyl or C.sub.1 -C.sub.4 alkoxycarbonyl; or pharmaceutically acceptable acid addition salts thereof.
  • 9. A compound claimed in claim 8 wherein X is nitro, X' is hydrogen, R.sup.1 is C.sub.1 -C.sub.4 alkyl, R.sup.2 is C.sub.1 -C.sub.4 alkyl, R.sup.3 is C.sub.1 -C.sub.8 straight or branched chain alkyl, or C.sub.3 -C.sub.7 cycloalkyl.
  • 10. A compound claimed in claim 9 wherein X is located at the 2 or 3 position of the phenyl.
  • 11. A compound claimed in claim 9 wherein R.sup.3 is cyclopentyl or cyclohexyl.
  • 12. A compound claimed in claim 8, namely, methyl 3-(n-butyl)-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate.
  • 13. A compound claimed in claim 8, namely, methyl 3-cyclobutyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate.
  • 14. A compound claimed in claim 8, namely, methyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate.
  • 15. A compound claimed in claim 8, namely, ethyl 3-cyclopentyl-1,6-dimethyl-4-(3-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate.
  • 16. A compound claimed in claim 8, namely, methyl 3-cyclohexyl-1,6-dimethyl-4-(2-nitrophenyl)-4,7-dihydropyrazolo[3,4-b]pyridine-5-carboxylate.
  • 17. An agent for treating cardiovascular diseases, comprising an effective amount for treating cardiovascular diseases of at least one substance selected from 4,7-dihydropyrazolo[3,4-b]pyridine derivatives represented by the formula: ##STR136## wherein R.sup.1 is (a) straight or branched chain C.sub.5 -C.sub.8 alkyl, (b) C.sub.4 -C.sub.6 cycloalkyl which may be substituted by lower alkyl, (c) C.sub.3 -C.sub.7 cycloalkyl (C.sub.1 -C.sub.4 )alkyl, (d) C.sub.1 -C.sub.4 alkoxy-(C.sub.1 -C.sub.4)alkyl, (e) C.sub.4 -C.sub.7 cycloalkyloxy(C.sub.1 -C.sub.4)alkyl, (f) phenoxy(C.sub.1 -C.sub.4)alkyl, (g) C.sub.1 -C.sub.4 alkylthio(C.sub.1 -C.sub.4)alkyl, (h) C.sub.4 -C.sub.7 cycloalkylthio(C.sub.1 -C.sub.4)alkyl, (i) phenylthio(C.sub.1 -C.sub.4)-alkyl, (j) C.sub.1 -C.sub.4 monalkylamino or C.sub.2 -C.sub.8 dialkylamino-substituted (C.sub.1 -C.sub.4)alkyl, (k) tetrahydrofuryl(C.sub.1 -C.sub.4)alkyl, (l) phenyl(C.sub.1 -C.sub.3)alkyl, which may have one or more substituents of halogen or C.sub.1 -C.sub.4 alkoxy, [or trifluoroalkyl,] (m) N-benzylpyrrolidinyl, or (n) N-benzylpiperidinyl; R.sup.2 is C.sub.1 -C.sub.4 alkyl; and R.sup.3 is C.sub.4 -C.sub.6 cycloalkyl or C.sub.3 -C.sub.7 cycloalkyl(C.sub.1 -C.sub.4)alkyl or the pharmaceutically acceptable acid addition salts thereof and a pharmaceutically acceptable carrier.
  • 18. An agent for treating cardiovascular diseases, comprising an effective amount for treating cardiovascular diseases of at least one substance selected from 4,7-dihydropyrazolo[3,4-b]pyridine derivatives represented by the formula: ##STR137## wherein X and X.sup.1 each is hydrogen, nitro, or halogen which may be located at the position or positions 2, 3, and/or 6; R.sup.1 is C.sub.1 -C.sub.4 alkyl; R.sup.2 is hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.4 -C.sub.6 cycloalkyl, or phenyl; R.sup.3 is hydrogen, C.sub.1 -C.sub.8 straight or branched chain alkyl, C.sub.3 -C.sub.7 cycloalkyl which may be substituted by C.sub.1 -C.sub.3 alkyl, phenyl which may be substituted by chlorine, trifluoromethyl, cyano, methoxy, methoxycarbonyl or ethoxycarbonyl, C.sub.7 -C.sub.9 aralkyl or C.sub.1 -C.sub.4 alkoxycarbonyl; or pharmaceutically acceptable acid addition salts thereof and a pharmaceutically acceptable carrier.
Priority Claims (2)
Number Date Country Kind
57-176763 Oct 1982 JPX
69-53118 Mar 1984 JPX
Parent Case Info

This is a CIP application of U.S. application Ser. No. 709,795 filed Mar. 8, 1985 now abandoned, and U.S. application Ser. No. 018,815, filed Feb. 19, 1987 now abandoned, the latter application being a continuation of U.S. application Ser. No. 527,733, filed Aug. 30, 1983 now abandoned.

US Referenced Citations (1)
Number Name Date Kind
4562256 Adachi et al. Dec 1985
Foreign Referenced Citations (2)
Number Date Country
0107619 May 1984 EPX
0114273 Aug 1984 EPX
Continuations (1)
Number Date Country
Parent 527733 Aug 1983
Continuation in Parts (2)
Number Date Country
Parent 709795 Mar 1985
Parent 18815 Feb 1987