Patents by Inventor Baldev Singh
Baldev Singh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 4431651Abstract: 3,4-Dihydro-3-R.sub.1 -4-R.sub.2 -5-Q-6-R-2(1H)-pyridinones (I), where R.sub.1 and R.sub.2 are each hydrogen or methyl, R is lower-alkyl, and Q is 4(or 3)-hydroxyphenyl, 4(or 3)-methoxyphenyl, 4(or 3)-pyridinyl or 4(or 3)-pyridinyl having one or two lower-alkyl substituents, or acid-addition salts thereof, and their preparation are shown. Also shown is the cardiotonic use of I where Q is 4(or 3)-hydroxyphenyl, 4(or 3)-pyridinyl or 4(or 3)-pyridinyl having one or two lower-alkyl substituents.Type: GrantFiled: November 18, 1982Date of Patent: February 14, 1984Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh, Philip M. Carabateas
-
Patent number: 4415578Abstract: 3-Methyl-4-(4-pyridinyl)benzeneamines, useful as cardiotonic agents, are prepared by reaction of pyridine, benzoyl chloride and an appropriate 3-methyl-N,N-di-lower-alkylbenzeneamine in the presence of copper powder and decomposing the reaction mixture with alkali and, if desired, reacting a resulting 3-methyl-4-(4-pyridinyl)-N,N-di-lower-alkylbenzeneamine with hydrogen bromide and pyridine to obtain 3-methyl-4-(4-pyridinyl)benzeneamine.Type: GrantFiled: February 8, 1982Date of Patent: November 15, 1983Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4415580Abstract: 1-R"-3-Q-4-R'-5-R-1,6-naphthyridin-2(1H)-ones (I) or salts thereof, where R is lower-alkyl, R' is hydrogen or methyl, R" is hydrogen or lower-alkyl, and Q is hydrogen, hydroxy, amino, cyano, carbamyl, carboxy or aminocarbamyl, are useful as cardiotonic agents (I, Q is hydrogen, hydroxy, amino, cyano or carbamyl) and/or intermediates therefor (I, Q is carboxy, aminocarbamyl, hydrogen, amino, cyano or carbamyl). Also shown are 3-Q"-4-R'-5-(RCO)-6-[2-(di-lower-alkylamino)ethenyl]-2(1H)-pyridinones (II) or salts thereof, where R and R' are as above and Q' is hydrogen or cyano, which are useful as cardiotonics (II, Q' is hydrogen) and/or intermediates (II, Q' is cyano or hydrogen). Processes for preparing the compounds of formulas I and II are shown.Type: GrantFiled: August 2, 1982Date of Patent: November 15, 1983Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4413127Abstract: The invention resides in a process for preparing cardiotonically active 1,2-dihydro-6-(lower-alkyl)-2-oxo-5-(pyridinyl)nicotinonitriles (III) which comprises reacting a pyridinylmethyl lower-alkyl ketone (I) with tri-(lower-alkyl) orthoformate, acetic anhydride and acetic acid to produce 2-(lower-alkoxy)-1-(pyridinyl)ethenyl lower-alkyl ketone (II) and then reacting II with malononitrile in a lower-alkanol, where pyridinyl is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents.Type: GrantFiled: May 24, 1982Date of Patent: November 1, 1983Assignee: Sterling Drug Inc.Inventor: Baldev Singh
-
Patent number: 4412077Abstract: 4-R.sub.2 -5-(Lower-alkanoyl)-6-(lower-alkyl)-2(1H)-pyridinones (I), useful as cardiotonics, where R.sub.2 is hydrogen or methyl, are prepared by reacting 2-(lower-alkanoyl)-1-(lower-alkyl)ethenamine (II) with lower-alkyl 2-propynoate or 2-butynoate respectively or by hydrolyzing 4-R.sub.2 -5-(lower-alkanoyl)-6-(lower-alkyl)-1,2-dihydro-2-oxonicotinonitrile (III, Q is CN) or corresponding 4-R.sub.2 -5-(lower-alkanoyl)-6-(lower-alkyl)-1,2-dihydro-2-oxonicotinamide to produce the corresponding 5-(lower-alkanoyl)-6-(lower-alkyl)-1,2-dihydro-2-oxonicotinic acid and decarboxylating said substituted nictotinic acid to produce I. Also disclosed and claimed are cardiotonic uses of 3-Q-4-R.sub.2 -5-(lower-alkanoyl)-6-(lower-alkyl)-2(1H)-pyridinones where Q is hydrogen or cyano and R.sub.2 is hydrogen or methyl (III). Also shown and claimed is methyl 4-acetyl-5-amino-2,4-hexadienoate or acid-addition salt thereof, useful as intermediate or cardiotonic.Type: GrantFiled: March 15, 1982Date of Patent: October 25, 1983Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4366319Abstract: 5-PY-benzoxazol-2(3H)-ones, cardiotonic agents, are prepared by reacting 2-amino-4-PY-phenol with a carbonylating agent, e.g., carbonyldiimidazole, where PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents. 5-PY-benzoxazol-2(3H)-ones or pharmaceutically-acceptable acid-addition or cationic salts thereof are disclosed as active components in cardiotonic compositions for increasing cardiac contractility and in the method for increasing cardiac contractility in a patient requiring such treatment.Type: GrantFiled: June 15, 1981Date of Patent: December 28, 1982Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4347363Abstract: A process for preparing cardiotonically active 1,2-dihydro-6-methyl-2-oxo-5-(pyridinyl)nicotinonitriles which comprises reacting a pyridinylmethyl methyl ketone with ethoxymethylenemalononitrile, where pyridinyl is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents.Type: GrantFiled: September 17, 1981Date of Patent: August 31, 1982Assignee: Sterling Drug Inc.Inventor: Baldev Singh
-
Patent number: 4346221Abstract: 4-Amino-2-R-6-PY-3(2H)-pyridazinones (I) or salts thereof, which are useful as cardiotonics, where R is hydrogen, lower-alkyl or lower-hydroxyalkyl, and PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents are prepared by: (a) reaction of 2-R-6-PY-3(2H)-pyridazinone (II) with hydrazine; (b) conversion from 2,3-dihydro-2-R-3-oxo-6-PY-4-pyridazinecarboxamide (III); or, (c) conversion form 2,3-dihydro-2-R-3-oxo-6-PY-4-pyridazinecarboxylic acid hydrazide (IV). Also shown are: the use of I or salts as cardiotonic agents; and, the preparation of intermediates.Type: GrantFiled: March 2, 1981Date of Patent: August 24, 1982Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, William B. Dickinson, Baldev Singh
-
Patent number: 4335132Abstract: 5-(Py-Y)-1H-benzimidazol-2-ol or 5-(Py-Y)-1H-benzimidazole-2-thiol or lower-alkyl ethers or thioethers thereof or pharmaceutically-acceptable acid-addition salts thereof, useful as cardiotonics, are prepared by reacting 4-(Py-Y)-1,2-benzenediamine with urear or carbonyldiimidazole to produce 5-(Py-Y)-1H-benzimidazol-2-ol or with thiourea, an alkali metal lower-alkyl xanthate or thiocarbonyldiimidazole to produce 5-(Py-Y)-1H-benzimidazole-2-thiol and by reacting 5-(Py-Y)-1H-benzimidazole-2-thiol with a lower-alkylating agent to produce 2-(lower-alkylthio)-5-(Py-Y)-1H-benzimidazole. 2-(Lower-alkoxy)-5-(Py-Y)-1H-benzimidazole is prepared by reacting 4-(Py-Y)-1,2-benzenediamine with tetra-(lower-alkoxy)methane.Type: GrantFiled: December 29, 1980Date of Patent: June 15, 1982Assignee: Sterling Drug, Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4331671Abstract: 2-R-5-(Py-Y)-1H-benzimidazole or pharmaceutically-acceptable acid-addition salt thereof, useful as a cardiotonic, is prepared by reacting 4-(Py-Y)-1,2-benzenediamine with a tri-(lower-alkyl)ortho-(lower-alkanoate) of the formula R--C(OR.sub.1).sub.3, where R is hydrogen or lower-alkyl, Y is a direct linkage or lower-alkylene having one or two carbon atoms, and Py is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents, or with dimethylformamide dimethyl acetal or dimethylacetamide dimethyl acetal to produce said 2-R-5-(Py-Y)-1H-benzimidazole where R is methyl or ethyl respectively. The same compound where R is lower-alkyl is prepared in two steps by first reacting 4-(Py-Y)-1,2-benzenediamine with an alkanoylating agent providing alkanoyl of the formula ##STR1## to produce N.sub.2 --[R'--C(.dbd.O)]-4-(Py-Y)-1,2-benzenediamine and heating the latter compound to produce said 2-R'-5-(Py-Y)-1H-benzimidazole, where R' is lower-alkyl.Type: GrantFiled: January 9, 1981Date of Patent: May 25, 1982Assignee: Sterling Drug Inc.Inventors: George V. Lesher, Baldev Singh
-
Patent number: 4310531Abstract: 5-PY-benzoxazol-2(3H)-ones, cardiotonic agents, are prepared by reacting 2-amino-4-PY-phenol with a carbonylating agent, e.g., carbonyldiimidazole, where PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents. 5-PY-benzoxazol-2(3H)-ones or pharmaceutically-acceptable acid-addition or cationic salts thereof are disclosed as active components in cardiotonic compositions for increasing cardiac contractility and in the method for increasing cardiac contractility in a patient requiring such treatment.Type: GrantFiled: November 24, 1980Date of Patent: January 12, 1982Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4305943Abstract: 4-Amino-2-R-6-PY-3(2H)-pyridazinones (I) or salts thereof, which are useful as cardiotonics, where R is hydrogen, lower-alkyl or lower-hydroxyalkyl, and PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents are prepared by: (a) reaction of 2-R-6-PY-3(2H)-pyridazinone (II) with hydrazine; (b) conversion from 2,3-dihydro-2-R-3-oxo-6-PY-4-pyridazinecarboxamide (III); or, (c) conversion form 2,3-dihydro-2-R-3-oxo-6-PY-4-pyridazinecarboxylic acid hydrazide (IV). Also shown are: the use of I or salts as cardiotonic agents; and, the preparation of intermediates.Type: GrantFiled: April 28, 1980Date of Patent: December 15, 1981Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, William B. Dickinson, Baldev Singh
-
Patent number: 4302462Abstract: 4(or 3)-(3,4-Dihydroxyphenyl)pyridine, a cardiotonic agent, is prepared by demethylating 4(or 3)-(3,4-dimethoxyphenyl)pyridine, preferably by heating with aqueous hydrogen bromide. 4(or3)-[3,4-di-(OR)-phenyl]pyridine, where R is hydrogen or methyl, or pharmaceutically-acceptable acid-addition salt thereof is disclosed as the active component in a cardiotonic composition for increasing cardiac contractility and in the method for increasing cardiac contractility in a patient requiring such treatment. The novel isomeric 2-[3,4-di-(OR)-phenyl]pyridine, where R is hydrogen or methyl, is shown for comparative purposes.Type: GrantFiled: August 4, 1980Date of Patent: November 24, 1981Assignee: Sterling Drug Inc.Inventors: Joseph C. Collins, George Y. Lesher, Baldev Singh
-
Patent number: 4297363Abstract: 2-Amino-3(4 or 5)-PY-phenol, a cardiotonic agent, is prepared by reducing 2-nitro-3(4 or 5)-PY-phenol, where PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents. 2-Amino-3(4 or 5)-PY-phenol or pharmaceutically-acceptable acid-addition salt thereof is disclosed as the active component in a cardiotonic composition for increasing cardiac contractility and in the method for increasing cardiac contractility in a patient requiring such treatment. The novel isomeric 4-amino-5-(4-pyridinyl)phenol is shown for comparative purposes.Type: GrantFiled: July 21, 1980Date of Patent: October 27, 1981Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4297362Abstract: 4-(3,4-Diaminophenyl)pyridine, a cardiotonic agent, is prepared by reducing 4-(4-amino-3-nitrophenyl)pyridine or preferably by reacting 4-(4-acetylamino-3-nitrophenyl)pyridine or 4-(3-acetylamino-4-nitrophenyl)pyridine with stannous chloride and hydrochloric acid. 4-(3,4-diaminophenyl)pyridine or pharmaceutically-acceptable acid-addition salt thereof is disclosed as the active ingredient in a cardiotonic composition for increasing cardiac contractility and in the method for increasing cardiac contractility in a patient requiring such treatment.Type: GrantFiled: July 28, 1980Date of Patent: October 27, 1981Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4118571Abstract: Compounds useful as anti-allergic agents are 2-Q-4-[XZC.dbd.C(R)NH]-5-R.sub.1 -6-R.sub.2 -pyrimidines (I), where Q is 4- or 3- or 2-pyridinyl or 4- or 3- or 2-pyridinyl having one or two lower-alkyl substituents or N-oxide thereof, R is hydrogen or lower-alkyl, R.sub.1 is hydrogen, lower-alkyl or cyano, R.sub.2 is hydrogen, lower-alkyl, hydroxy or halo, X and Z are the same or different and are each selected from lower-carbalkoxy, lower-alkanoyl, carbamyl and cyano, or ##STR1## is ##STR2## where R.sub.3 and R.sub.4 are each lower-alkyl, or X is hydrogen, are prepared by reacting 4-amino-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidine (II where Q' is amino) with R'O--C(R).dbd.CXZ (III). Preparations of II are given. Also shown as intermediates and/or anti-allergic agents are 4-(AcNH)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (IV) and 4-(R.sub.5 R.sub.6 N)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (V) where Ac is lower-alkanoyl or lower-carbalkoxy, R.sub.5 is hydrogen, lower-alkyl or lower-hydroxyalkyl, and R.sub.Type: GrantFiled: November 30, 1977Date of Patent: October 3, 1978Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4109092Abstract: The process of reacting a PY-carboxamidine with .alpha.-chloroacrylonitrile in the presence of an acid-acceptor to produce 2-PY-4-pyrimidinamines where PY is 4- or 3- or 2-pyridinyl or 4- or 3- or 2-pyridinyl having one or two lower-alkyl substituents. The products produced by the process are useful as anti-allergic agents per se and, also, are useful as intermediates in the preparation of other anti-allergic agents, namely, dialkyl N-(2-PY-4-pyrimidinyl)-aminomethylenemalonates and analogs, as well as N-(2-PY-4-pyrimidinyl)ureas.Type: GrantFiled: October 7, 1976Date of Patent: August 22, 1978Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4086233Abstract: Compounds useful as anti-allergic agents are 2-Q-4-[XZC=C(R)NH]-5-R.sub.1 -6-R.sub.2 -pyrimidines (I), where Q is 4- or 3- or 2-pyridinyl or 4- or 3- or 2-pyridinyl having one or two lower-alkyl substituents or N-oxide thereof, R is hydrogen or lower-alkyl, R.sub.1 is hydrogen, lower-alkyl or cyano, R.sub.2 is hydrogen, lower-alkyl, hydroxy or halo, X and Z are the same or different and are each selected from lower-carbalkoxy, lower-alkanoyl, carbamyl and cyano, or ##STR1## is ##STR2## wherein R.sub.3 and R.sub.4 are each lower-alkyl, or X is hydrogen, are prepared by reacting 4-amino-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidine (II where Q' is amino) with R'O-C(R)=CXZ (III). Preparations of II are given. Also shown as intermediates and/or anti-allergic agents are 4-(AcNH)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (IV) and 4-(R.sub.5 R.sub.6 N)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (V) where Ac is lower-alkanoyl or lower-carbalkoxy, R.sub.5 is hydrogen, lower-alkyl or lower-hydroxyalkyl, and R.sub.Type: GrantFiled: February 3, 1977Date of Patent: April 25, 1978Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: 4053475Abstract: N--R.sub.3 --N--R.sub.4 --N'--(2--Q--5--R.sub.1 --6--R.sub.2 --4-Pyrimidinyl)ureas which are useful as anti-allergic agents are prepared by reacting a 2--Q--4--RNH--5--R.sub.1 --6--R.sub.2 -pyrimidine with an R.sub.4 '-isocyanate and reacting the intermediate product with 1,1'-carbonyldiimidasole.Type: GrantFiled: July 12, 1976Date of Patent: October 11, 1977Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh
-
Patent number: RE30024Abstract: Compounds useful as anti-allergic agents are 2-Q-4-[XZC.dbd.C(R)NH]-5-R.sub.1 -6-R.sub.2 -pyrimidines (I), where Q is 4- or 3- or 2-pyridinyl or 4- or 3- or 2-pyridinyl having one or two lower-alkyl substituents or N-oxide thereof, R is hydrogen or lower-alkyl, R.sub.1 is hydrogen, lower-alkyl or cyano, R.sub.2 is hydrogen, lower-alkyl, hydroxy or halo, X and Z are the same or different and are each selected from lower-carbalkoxy, lower-alkanoyl, carbamyl and cyano, or ##STR1## is ##STR2## where R.sub.3 and R.sub.4 are each lower-alkyl, or X is hydrogen, are prepared by reacting 4-amino-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidine (II where Q' is amino) with R'O--C(R).dbd.CXZ (III). Preparation of II are given. Also shown as intermediates and/or anti-allergic agents are 4-(AcNH)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (IV) and 4-(R.sub.5 R.sub.6 N)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (V) where Ac is lower-alkanoyl or lower-carbalkoxy, R.sub.5 is hydrogen, lower-alkyl or lower-hydroxyalkyl, and R.sub.Type: GrantFiled: June 5, 1978Date of Patent: June 5, 1979Assignee: Sterling Drug Inc.Inventors: George Y. Lesher, Baldev Singh