Patents by Inventor Toichi Takenaka

Toichi Takenaka 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: 5616715
    Abstract: A process is provided for producing diastereoisomer A or a pharmaceutically acceptable acid addition salt of 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-(1-benzylpyrrolidin-3-yl) ester 5-methyl ester which comprises subjecting a mixture of diastereoisomers A and B of 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-(1-benzylpyrrolidin-3-yl) ester 5-methyl ester to column chromatography using silica gel as a carrier and a mixture of ethyl acetate and acetic acid as an eluant, and then separating the acetate of diastereoisomer A from the eluate, or treating the acetate with a base, or further treating the resulting diastereoisomer A with a pharmaceutically acceptable acid.
    Type: Grant
    Filed: June 19, 1995
    Date of Patent: April 1, 1997
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuharu Tamazawa, Tadao Kojima, Hideki Arima, Yukiyasu Murakami, Yasuo Isomura, Minoru Okada, Toichi Takenaka, Kiyoshi Takanobu
  • Patent number: 5591757
    Abstract: Pharmaceutical composition of certain dihydropyridine compounds and salts thereof are provided which exhibit both Ca.sup.2+ -antagonistic and adrenergic beta-receptor blocking activities and therefore are useful for the treatment of ischemic heart diseases and hypertension. The pharmaceutical compositions contains either 4-(2-hydroxy-3-phenoxy-propylamino)-butyl methyl 2,6-dimethyl-4-(m-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate or 6-(2-hydroxy-3-phenoxypropylamino) hexyl methyl 2,6-dimethyl-4-(m-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate or their pharmaceutically acceptable salts.
    Type: Grant
    Filed: April 6, 1995
    Date of Patent: January 7, 1997
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Takashi Fujikura, Noriki Ito, Yuzo Matsumoto, Masaharu Asano, Toichi Takenaka
  • Patent number: 5463064
    Abstract: A dextro-rotatory optical isomer of diastereoisomer A of (.+-.)-2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-(1-benzylpyrrolidin-3-yl)ester 5-methyl ester is provided having the formula ##STR1## and wherein the melting point of the hydrochloride of the dextro-rotatory optical isomer is 223.degree. to 230.degree. C. (decomp.), or a pharmaceutically acceptable acid addition salt thereof.
    Type: Grant
    Filed: May 5, 1994
    Date of Patent: October 31, 1995
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuharu Tamazawa, Tadao Kojima, Hideki Arima, Yukiyasu Murakami, Yasuo Isomura, Minoru Okada, Kiyoshi Takanobu, Toichi Takenaka
  • Patent number: 5364872
    Abstract: The diastereoisomer A of a dihydropyridine-3,5-dicarboxylic acid ester derivative is provided as well as its pharmaceutically acceptable acid addition salts. The invention further discloses a process for producing the compounds and their use as medicaments in imparting vasodilating activity.
    Type: Grant
    Filed: January 23, 1992
    Date of Patent: November 15, 1994
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuharu Tamazawa, Tadao Kojima, Hideki Arima, Yukiyasu Murakami, Yasuo Isomura, Minoru Okada, Toichi Takenaka, Kiyoshi Takanobu
  • Patent number: 5198587
    Abstract: Phenethylamine derivatives shown by the general formula ##STR1## wherein Ro represents a lower alkyl group; R.sub.1 represents a lower alkyl group or a lower alkoxy group; R.sub.2 represents hydrogen atom or a hydroxyl group; R.sub.3 and R.sub.4 each represents hydrogen atom or a lower alkyl group; R.sub.5 represents hydrogen atom or a lower alkoxy group; X represents oxygen atom or a methylene group; m is an integer of 1-3; and n is an integer of 0-2 and the acid addition salts thereof.These compounds exhibit a strong .alpha.-adrenergic blocking action and are useful as an antihypertensive agent.
    Type: Grant
    Filed: July 30, 1991
    Date of Patent: March 30, 1993
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuo Imai, Kunihiro Niigata, Takashi Fujikura, Shinichi Hashimoto, Toichi Takenaka, Kazuo Honda
  • Patent number: 5110820
    Abstract: Dihydropyridine compounds and salts thereof are provided which exhibit both Ca.sup.2+ -antagonistic and adrenergic beta-receptor blocking activities and therefore are useful for the treatment of ischemic heart diseases and hypertension. The compounds have the formula ##STR1## wherein A represents a straight or branched carbon chain alkylene group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom(s); R.sup.1 and R.sup.4, which may be the same or different, each represents a lower alkyl group; R.sup.2 represents an amino group, ##STR2## R.sup.3 represents a straight or branched carbon chain alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom(s), or ##STR3## R.sup.5 and R.sup.6, which may be the same or different, each represents a hydrogen atom, a nitro group, a halogen atom, a trifluoromethyl group, a cyano group, a lower alkyl group, a lower alkoxy group or a lower alkenyloxy group; R.sup.
    Type: Grant
    Filed: November 13, 1990
    Date of Patent: May 5, 1992
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Takashi Fujikura, Noriki Ito, Yuzo Matsumoto, Masaharu Asano, Toichi Takenaka
  • Patent number: 5063246
    Abstract: Phenethylamine derivatives shown by the general formula ##STR1## wherein Ro represents a lower alkyl group; R.sub.1 represents a lower alkyl group or a lower alkoxy group, R.sub.2 represents hydrogen atom or a hydroxyl group; R.sub.3 and R.sub.4 each represents hydrogen atom or a lower alkyl group; R.sub.5 represents hydrogen atom or a lower alkoxy group; X represents oxygen atom or a methylene group; m is an integer of 1-3; and n is an integer of 0-2and the acid addition salts thereof.These compounds exhibit a strong .alpha.-adrenergic blocking action and are useful as an antihypertensive agent.
    Type: Grant
    Filed: August 21, 1990
    Date of Patent: November 5, 1991
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuo Imai, Kunihiro Niigata, Takashi Fujikura, Shinichi Hashimoto, Toichi Takenaka, Kazuo Honda
  • Patent number: 4880841
    Abstract: Phenethylamine derivatives shown by the general formula ##STR1## wherein Ro represents a lower alkyl group; R.sub.1 represents a lower alkyl group or a lower alkoxy group; R.sub.2 represents hydrogen atom or a hydroxyl group; R.sub.3 and R.sub.4 each represents hydrogen atom or a lower alkyl group; R.sub.5 represents hydrogen atom or a lower alkoxy group; X represents oxygen atom or a methylene group; m is an integer of 1 -3; and n is an integer of 0-2 and the acid addition salts thereof.These compounds exhibit a strong .alpha.-adreneregic blocking action and are useful as an antihypertensive agent.
    Type: Grant
    Filed: February 3, 1989
    Date of Patent: November 14, 1989
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuo Imai, Kunihiro Niigata, Takashi Fujikura, Shinichi Hashimoto, Toichi Takenaka, Kazuo Honda
  • Patent number: 4868216
    Abstract: Novel sulfamoyl-substituted phenethylamine derivatives which exhibit .alpha.-adrenergic blocking action and are useful as an antihypertensive agent and an agent for the treatment of congestive heart failure.
    Type: Grant
    Filed: February 14, 1989
    Date of Patent: September 19, 1989
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuo Imai, Kunihiro Niigata, Takashi Fujikura, Shinichi Hashimoto, Toichi Takenaka
  • Patent number: 4727082
    Abstract: A dihydropyridine compound of the following general formula (I) or a salt thereof: ##STR1## wherein R.sup.1 and R.sup.2, which are the same or different, each represents a C.sub.1 to C.sub.10 alkyl group, a lower alkyl group which is interrupted by oxygen atom(s), or a lower alkyl group substituted by C.sub.3 to C.sub.6 alicyclic group(s); R.sup.3 and R.sup.4, which are the same or different, each represents a lower alkyl group; R.sup.5 and R.sup.6, which are the same or different, each represents a hydrogen atom, a nitro group, a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkylthio group, a lower alkylsulfonyl group, or a lower alkylsulfinyl group; R.sup.7 and R.sup.8, which are the same or different, each represents a hydrogen atom, a halogen atom, a cyano group, a lower alkoxy group, or a lower alkanoylamino group, or R.sup.7 may combine with R.sup.8 to form a naphthyl group together with the adjacent phenyl group; A represents a single bond, a vinylene group (--CH.dbd.
    Type: Grant
    Filed: September 17, 1986
    Date of Patent: February 23, 1988
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Takashi Fujikura, Noriki Ito, Yuzo Matsumoto, Yasuo Isomura, Masaharu Asano, Toichi Takenaka
  • Patent number: 4703063
    Abstract: Novel sulfamoyl-substituted phenethylamine derivatives which exhibit .alpha.-adrenergic blocking action and are useful as an antihypertensive agent and an agent for the treatment of congestive heart failure.
    Type: Grant
    Filed: July 18, 1985
    Date of Patent: October 27, 1987
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuo Imai, Kunihiro Niigata, Takashi Fujikura, Shinichi Hashimoto, Toichi Takenaka
  • Patent number: 4558156
    Abstract: Novel sulfamoyl-substituted phenethylamine derivatives which exhibit .alpha.-adrenergic blocking action and are useful as an antihypertensive agent and an agent for the treatment of congestive heart failure.
    Type: Grant
    Filed: July 18, 1984
    Date of Patent: December 10, 1985
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuo Imai, Kunihiro Niigata, Takashi Fujikura, Shinichi Hashimoto, Toichi Takenaka
  • Patent number: 4373106
    Abstract: Novel sulfamoyl-substituted phenethylamine derivatives which exhibit .alpha.-adrenergic blocking action and are useful as an antihypertensive agent and an agent for the treatment of congestive heart failure.
    Type: Grant
    Filed: February 4, 1981
    Date of Patent: February 8, 1983
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuo Imai, Kunihiro Niigata, Takashi Fujikura, Shinichi Hashimoto, Toichi Takenaka
  • Patent number: 4220649
    Abstract: 1,4-Dihydropyridine-3,5-dicarboxylic acid ester derivatives shown by the formula ##STR1## wherein R represents a lower alkyl group and R' represents a hydrogen atom, a lower alkyl group or an aralkyl group, and the therapeutically non-toxic salts thereof.These compounds possess a vasodilative activity and an antihypertensive activity.
    Type: Grant
    Filed: January 31, 1979
    Date of Patent: September 2, 1980
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Tadao Kojima, Toichi Takenaka
  • Patent number: 4217305
    Abstract: Novel phenylethanolamine derivatives represented by the formula ##STR1## wherein R represents a hydrogen atom, a halogen atom, a hydroxyl group, a lower alkyl group, a lower alkoxy group, a lower alkylthio group, an amino group, a lower acylamino group, a lower alkylsulfonyl group, or a lower alkylsulfonylamino group; R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which may be the same or different, each represents hydrogen or a lower alkyl group; R.sub.5 represents an aryl group which may have a substituent, a benzodioxane ring group which may have a substituent, an aryloxy group which may have a substituent, or an arylthio group which may have a substituent; said R.sub.5 being, however, a benzodioxane ring group which may have a substituent, an aryloxy group which may have a substituent, or an arylthio group which may have a substituent when R is a hydroxyl group; and n represents 0 or an integer of 1-3 and the acid addition salts thereof.The compounds of this invention exhibit .alpha.- and .beta.
    Type: Grant
    Filed: September 27, 1978
    Date of Patent: August 12, 1980
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Kazuo Imai, Kunihiro Niigata, Takashi Fujikura, Shinichi Hashimoto, Toichi Takenaka
  • Patent number: 4145363
    Abstract: There are disclosed novel 4-substituted amino-.alpha.-aminomethylbenzyl alcohol derivatives represented by the formula: ##STR1## wherein X represents a halogen atom; Y represents a hydrogen atom or a halogen atom; R.sub.1 represents a lower alkyl group, a carbamoyl group, a mono- or di-lower alkyl-substituted carbamoyl group, a phenyl-substituted carbamoyl group, a lower alkoxycarbonyl group, a lower alkoxy-substituted lower alkoxycarbonyl group, a phenyl-substituted lower alkoxycarbonyl group, or a cycloalkyloxycarbonyl group; and R.sub.2 represents a lower alkyl group, a cycloalkyl group, or the group shown by the ##STR2## wherein R.sub.3 represents a hydrogen atom or a lower alkyl group and R.sub.4 represents a hydrogen atom, a hydroxy group, or a lower alkoxy group and the pharmaceutically acceptable nontoxic salts thereof.These compounds are antiasthmatic agents useful for the prophylaxis and treatment of asthma.
    Type: Grant
    Filed: June 27, 1977
    Date of Patent: March 20, 1979
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Masuo Murakami, Kozo Takahashi, Kiyoshi Murase, Toshiyasu Mase, Hisashi Ida, Toichi Takenaka
  • Patent number: 4127675
    Abstract: Novel indene derivatives represented by the general formula ##STR1## wherein R represents lower alkyl, phenylloweralkyl or lower cycloalkyl, and acid addition salts thereof useful as .beta.-receptor antagonists.
    Type: Grant
    Filed: October 21, 1976
    Date of Patent: November 28, 1978
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Masuo Murakami, Kiyoshi Murase, Kunihiro Niigata, Shiro Tachikawa, Toichi Takenaka
  • Patent number: 4063025
    Abstract: There are disclosed novel 4-substituted amino-.alpha.-aminomethylbenzyl alcohol derivatives represented by the formula: ##STR1## wherein X represents a halogen atom; Y represents a hydrogen atom or a halogen atom; R.sub.1 represents a lower alkyl group, a carbamoyl group, a mono- or di-lower alkyl-substituted carbamoyl group, a phenyl-substituted carbamoyl group, a lower alkoxycarbonyl group, a lower alkoxy-substituted lower alkoxycarbonyl group, a phenyl-substituted lower alkoxycarbonyl group, or a cycloalkyloxycarbonyl group; and R.sub.2 represents a lower alkyl group, a cycloalkyl group, or the group shown by the formula ##STR2## wherein R.sub.3 represents a hydrogen atom or a lower alkyl group and R.sub.4 represents a hydrogen atom, a hydroxy group, or a lower alkoxy group and the pharmaceutically acceptable nontoxic salts thereof.These compounds are antiasthmatic agents useful for the prophylaxis and treatment of asthma.
    Type: Grant
    Filed: January 23, 1976
    Date of Patent: December 13, 1977
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Masuo Murakami, Kozo Takahashi, Kiyoshi Murase, Toshiyasu Mase, Hisashi Ida, Toichi Takenaka
  • Patent number: 4045482
    Abstract: Novel indene derivatives represented by the general formula ##STR1## wherein R represents lower alkyl, phenylloweralkyl or lower cycloalkyl, and acid addition salts thereof useful as .beta.-receptor antagonists.
    Type: Grant
    Filed: April 14, 1975
    Date of Patent: August 30, 1977
    Assignee: Yamanouchi Pharmaceutical Co. Ltd.
    Inventors: Masuo Murakami, Kiyoshi Murase, Kunihiro Niigata, Shiro Tachikawa, Toichi Takenaka
  • Patent number: 4021434
    Abstract: Novel 1-substituted-1, 4-dihydropyridine derivatives, particularly diethyl 1-ethoxymethyl-4-(3-nitrophenyl)-2, 6-dimethyl-1, 4-dihydropyridine-3,5-dicarboxylate are provided. The novel derivatives have cerebral vascular dilator activity with low toxicity.
    Type: Grant
    Filed: August 21, 1975
    Date of Patent: May 3, 1977
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Masuo Murakami, Kozo Takahashi, Teruaki Ozasa, Kazuharu Tamazawa, Ryutaro Kawai, Toichi Takenaka, Norio Sato