Patents by Inventor Chikara Murakata

Chikara Murakata 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: 5733924
    Abstract: DC107 derivatives represented by the formula (I): ##STR1## or pharmacologically acceptable slats thereof, ?wherein R.sup.1 is hydrogen, lower alkoxyalkyl, aralkyloxyalkyl, lower alkoxyalkoxyalkyl, lower alkoxyalkoxyalkoxyalkyl, aralkyl, tetrahydropyranyl, COR.sup.4 or the like; R.sup.2 represents hydrogen or COR.sup.5 ; R.sup.3 represents lower alkyl, lower alkenyl, aralkyl which may be substituted with substituted or unsubstituted aryl, lower alkoxyalkyl, aralkyloxyalkyl, substituted or unsubstituted aryloxyalkyl, lower alkoxycarbonylalkyl, lower alkanoyloxyalkyl, alicyclic alkanoyloxyalkyl or the like, or bonds to Y to represent a single bond; Y bonds to R.sup.3 to represent a single bond, or bonds to Z to represent a single bond; Z represents hydrogen or bonds to Y to represent a single bond; W represents oxygen or NR.sup.6, with the proviso that the compound wherein R.sup.1, R.sup.2 and Z each represents hydrogen, R.sup.3 bonds to Y to represent a single bond, and W represents oxygen (DC107) is excluded.
    Type: Grant
    Filed: April 17, 1997
    Date of Patent: March 31, 1998
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Yutaka Kanda, Yutaka Saitoh, Hiromitsu Saito, Tadashi Ashizawa, Kazuyo Sugiyama, Katsushige Gomi, Shingo Kakita, Yuichi Takahashi, Chikara Murakata
  • Patent number: 5728709
    Abstract: Described herein is a pyrrolocarbazole derivative and a pharmaceutically acceptable salt thereof having the following formula (I): ##STR1## wherein R.sup.1 is lower alkyl or aralkyl; R.sup.2 is hydrogen, substituted or unsubstituted lower alkyl, lower alkenyl, or substituted or unsubstituted aralkyl; R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 may be the same or different, and are hydrogen, halogen, nitro, substituted or unsubstituted lower alkanoyl, NR.sup.9 R.sup.10, or OR.sup.11 ; R.sup.8 is hydrogen or is combined with R.sup.3 to form --CONR.sup.12 --; and when R.sup.1 is benzyl; R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are not simultaneously hydrogen. A compound of the present invention stimulates platelet production and is useful for treatment of thrombocytopenia.
    Type: Grant
    Filed: November 8, 1996
    Date of Patent: March 17, 1998
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Yoji Ikuina, Chikara Murakata, Yutaka Saitoh, Yukimasa Shiotsu, Takako Iida, Tatsuya Tamaoki, Kinya Yamashita, Shiro Akinaga
  • Patent number: 5674867
    Abstract: The present invention relates to therapeutic agents for thrombocytopenia which contain an indolocarbazole derivative represented by the formula (I) given below or a pharmaceutically acceptable salt thereof as an active ingredient, and to novel indolocarbazole derivatives.
    Type: Grant
    Filed: May 18, 1994
    Date of Patent: October 7, 1997
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Tatsuya Tamaoki, Yukimasa Shiotsu, Chikara Murakata, Shiro Akinaga, Masami Okabe, Yutaka Saito, Junichi Watanabe, Takako Shiraki
  • Patent number: 5654427
    Abstract: The invention features a method of treating a pathological condition of the prostate gland, e.g., benign prostatic hypertrophy or prostate cancer, in a mammal, said method comprising administering to said mammal a therapeutic amount of the indolocarbazole compound K-252a or a preferred derivative thereof. The invention also includes novel derivatives of K-252a.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: August 5, 1997
    Assignees: Kyowa Hakko Kogyo Co., Ltd., Cephalon, Inc.
    Inventors: Craig A. Dionne, Patricia C. Contreras, Chikara Murakata
  • Patent number: 5629304
    Abstract: The present invention provides a method of treating thrombocytopenia, which comprises administering to a patient suffering from thrombocytopenia, an effective amount of an indolocarbazole derivative represented by formula (I): ##STR1## wherein R.sup.1 represents a hydrogen atom, a substituted or unsubstituted lower alkyl group, a substituted or unsubstituted aralkyl group or a tetrahydropyranyl group; R.sup.2A and R.sup.3A, which may be the same or different, each represent a hydrogen atom, a substituted or unsubstituted lower alkyl group, a lower alkenyl group, a substituted or unsubstituted aralkyl group or a monosaccharide residue where a hydroxyl group at the anomer position is removed; R.sup.4A and R.sup.5A, which may be the same or different, each represent a hydrogen atom, a formyl group, a hydroxyl group or a halogen atom; W.sup.A1 and W.sup.A2 represent hydrogen atoms or are combined together to form an oxygen atom; and X.sup.A1 and X.sup.
    Type: Grant
    Filed: April 25, 1996
    Date of Patent: May 13, 1997
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Chikara Murakata, Fumihiko Kanai, Yutaka Saitoh, Yukimasa Shiotsu, Takako Shiraki, Tatsuya Tamaoki, Shiro Akinaga, Masami Okabe
  • Patent number: 5621101
    Abstract: The invention features novel derivatives of K-252a, as well as novel bis-N-substituted derivatives of staurosporine. The invention also features a method for treating diseased neuronal cells involving the administration of either the novel staurosporine derivatives or specified functional derivatives of K-252a.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: April 15, 1997
    Assignees: Cephalon, Inc., Kyowa Hakko Kogyo
    Inventors: Michael E. Lewis, James C. Kauer, Nicola Neff, Jill Roberts-Lewis, Chikara Murakata, Hiromitsu Saito, Yuzuru Matsuda, Marcie A. Glicksman, Fumihiko Kanai, Masami Kaneko
  • Patent number: 5621100
    Abstract: The invention features novel derivatives of K-252a, as well as novel bis-N-substituted derivatives of staurosporine. The invention also features a method for treating diseased neuronal cells involving the administration of either the novel staurosporine derivatives or specified functional derivatives of K-252a.
    Type: Grant
    Filed: October 26, 1994
    Date of Patent: April 15, 1997
    Assignees: Cephalon, Inc., Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Michael E. Lewis, James C. Kauer, Nicola Neff, Jill Roberts-Lewis, Chikara Murakata, Hiromitsu Saito, Yuzuru Matsuda, Marcie A. Glicksman, Fumihiko Kanai, Masami Kaneko
  • Patent number: 5604219
    Abstract: Disclosed is an indolocarbazole derivative represented by the following formula (I), or a pharmaceutically acceptable salt thereof: ##STR1## [wherein R.sup.1 represents substituted or unsubstituted lower alkyl, R.sup.2 represents hydrogen, substituted or unsubstituted lower alkyl, R.sup.3 and R.sup.4 are the same or different, and represent hydrogen, nitro, NR.sup.5 R.sup.6, OR.sup.9, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkenyl, or CH.dbd.NNR.sup.10 R.sup.11, W represents two hydrogen atoms or oxygen, and Me represents methyl, provided that when R.sup.1 is unsubstituted lower alkyl, R.sup.3 and R.sup.4 are not simultaneously hydrogen.
    Type: Grant
    Filed: March 16, 1995
    Date of Patent: February 18, 1997
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Chikara Murakata, Junichi Watanabe, Yutaka Saitoh, Yukimasa Shiotsu, Takako Shiraki, Fumihiko Kanai, Tatsuya Tamaoki, Shiro Akinaga, Masami Okabe
  • Patent number: 5585488
    Abstract: In the formulae, R.sup.1, R.sup.2, and R.sup.3 independently represent lower alkyl or aryl, and R.sup.4 represents lower alkyl.The present invention relates to a process for producing an indolocarbazole derivative represented by Formula (II), comprising the acidic treatment of a silylated indolocarbazole derivative represented by Formula (VI).
    Type: Grant
    Filed: February 23, 1996
    Date of Patent: December 17, 1996
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Masahiko Kinugawa, Yoshiaki Masuda, Yukiteru Mimura, Chikara Murakata, Hiromitsu Saito, Takehiro Ogasa, Masaji Kasai, Shinji Tomioka
  • Patent number: 5516772
    Abstract: Disclosed are derivatives of the indolocarbazole alkaloid K-252a of the Formulae I-VI, useful for enhancing neurotrophin-induced activity of neurotrophin responsive cells. A particularly preferred neurotrophin is NT-3, and a particularly preferred neurotrophin responsive cell is one which comprises a trk receptor. The enhanced neurotrophin-induced activity occasioned by the disclosed K-252a derivatives may be determined by the following assays: ChAT activity; DRG neuronal survival; or cell division (mitogenesis).
    Type: Grant
    Filed: September 16, 1994
    Date of Patent: May 14, 1996
    Assignees: Cephalon, Inc., Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Marcie A. Glicksman, Robert L. Hudkins, David P. Rotella, Nicola T. Neff, Chikara Murakata
  • Patent number: 5516771
    Abstract: The invention features a method of treating a pathological condition of the prostate gland, e.g., benign prostatic hypertrophy or prostate cancer, in a mammal, said method comprising administering to said mammal a therapeutic amount of the indolocarbazole compound K-252a or a preferred derivative thereof. The invention also includes novel derivatives of K-252a.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: May 14, 1996
    Assignees: Cephalon, Inc., Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Craig A. Dionne, Patricia C. Contreras, Chikara Murakata
  • Patent number: 5468872
    Abstract: Functional K-252a derivatives are used to enhance trk phosphorylation and to potentiate the activity of neurotrophin-3 (NT-3). These compounds can be used to treat neurological disorders, alone or in combination with NT-3.
    Type: Grant
    Filed: September 16, 1993
    Date of Patent: November 21, 1995
    Assignees: Cephalon, Inc., Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Marcie A. Glicksman, David P. Rotella, Nicola Neff, Chikara Murakata
  • Patent number: 5461146
    Abstract: The invention features novel derivatives of K-252a, as well as novel bis-N-substituted derivatives of staurosporine. Also, a method for treating diseased neuronal cells involving the administration of either the novel staurosporine derivatives or specified functional derivatives of K-252a.
    Type: Grant
    Filed: July 22, 1993
    Date of Patent: October 24, 1995
    Assignees: Cephalon, Inc., Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Michael E. Lewis, James C. Kauer, Nicola Neff, Jill Roberts-Lewis, Chikara Murakata, Hiromitsu Saito, Yuzuru Matsuda, Marcie A. Glicksman
  • Patent number: 5344926
    Abstract: Disclosed is a process for producing a staurosporine derivative represented by Formula (I): Q is defined as in specification: ##STR1## The staurosporine derivative (I-1) possesses selective protein kinase C-inhibitory and cell growth-inhibiting activities, and platelet-increasing activity.
    Type: Grant
    Filed: June 22, 1993
    Date of Patent: September 6, 1994
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Chikara Murakata, Toshimitsu Takiguchi, Shigeo Katsumata, Akira Mihara, Keiichi Takahashi, Hiromitsu Saito, Shiro Akinaga, Masami Okabe, Yutaka Saito
  • Patent number: 5011854
    Abstract: A hydroxamic acid compound represented by the general formula (I) or a salt thereof; ##STR1## wherein R.sup.1 represents a hydrogen atom, or a substituted or unsubstituted alkanoyl group, R.sup.2 represents an unsubstituted alkanoyl, substituted lower alkanoyl or substituted lower alkyl group, and m represents an integer of 3 to 7, which are useful for the prevention and/or treatment of diseases caused by lipoxygenase-mediated metablites.
    Type: Grant
    Filed: December 7, 1989
    Date of Patent: April 30, 1991
    Assignee: Kyowa Hakko Kogyo Co. Ltd.
    Inventors: Mitsuru Takahashi, Shigeto Kitamura, Hiroshi Kase, Masaji Kasai, Isao Kawamoto, Takao Iida, Hiroshi Sano, Hiromitsu Saito, Koji Yamada, Chikara Murakata
  • Patent number: 5004833
    Abstract: Disclosed are KS-501 derivatives represented by the formula (I) ##STR1## wherein X represents a hydrogen atom or COOR.sub.3, Y represents hydroxy or ##STR2## and R.sub.1, R.sub.2 and R.sub.3 are the same or different and represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, provided that when R.sub.1, R.sub.2 and R.sub.3 are simultaneously hydrogen atoms, and when R.sub.1, R.sub.2 and X are simultaneously hydrogen atoms, Y does not represent ##STR3## and a pharmaceutically acceptable acid addition salt thereof. The KS-501 derivatives have a platelet aggregation-inhibiting property, and are expected to be useful as antithrombotic agent.
    Type: Grant
    Filed: September 15, 1989
    Date of Patent: April 2, 1991
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Toru Yasuzawa, Satoshi Nakanishi, Chikara Murakata, Hiroshi Kase, Hiroshi Sano, Koji Yamada
  • Patent number: 4923986
    Abstract: The present invention relates to novel derivatives of K-252, (8R*, 9S*, 11S*)-(-)-9-hydroxy-9-methoxycarbonyl-8-methyl-2,3,9,10-tetrahydro-8,11-ep oxy-1H,8H, 11H-2,7b,11a-triazadibenzo[a,g]cycloocta-[c,d,e,]trinden-1-one, and the compounds are represented by formula (I): ##STR1## wherein W.sub.1, W.sub.2, R.sup.1, R.sup.2, R.sup.3, R.sup.4, X and Y represent various substituents. The compounds are physiologically active substances that inhibit protein kinase C and exhibit an antitumor activity, and are useful as medicines.
    Type: Grant
    Filed: November 8, 1988
    Date of Patent: May 8, 1990
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Chikara Murakata, Akira Sato, Mitsuru Takahashi, Eiji Kobayashi, Makoto Morimoto, Shiro Akinaga, Tadashi Hirata, Kenichi Mochida, Hiroshi Kase, Koji Yamada, Kazuyuki Iwashashi
  • Patent number: 4877776
    Abstract: A K-252 compound represented by the formula: ##STR1## wherein R.sup.1 and R.sup.2 are independently H or OH; X represents COOH, COOR or CH.sub.2 OH; Y represents H, R or COR; and Z represents OH, OR or SR, wherein R represents lower alkyl has C-kinase inhibitory activity and is expected to be useful as an active ingredient of anti-tumor agents, etc.
    Type: Grant
    Filed: December 22, 1988
    Date of Patent: October 31, 1989
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Chikara Murakata, Akira Sato, Masaji Kasai, Eiji Kobayashi, Makoto Morimoto, Shiro Akinaga
  • Patent number: 4588729
    Abstract: Offered is an anticonvulsive composition which comprises an effective amount of a dihydrouracil derivative represented by the formula: ##STR1## [wherein one of A and B is ##STR2## (wherein Y.sub.1, Y.sub.2 and Y.sub.3 are hydrogen atoms, lower alkyl groups, halogen atoms, nitro groups, amino groups, carboxyl groups, lower alkoxycarbonyl groups or trifluoromethyl groups), a naphthyl group or a diphenylmethyl group, and the other is a hydrogen atom, a lower alkyl group, a lower alkenyl group, a cyclopentyl group, a cyclohexyl group or ##STR3## (wherein Z.sub.1, Z.sub.2 and Z.sub.3 are hydrogen atoms, lower alkyl groups, halogen atoms or trifluoromethyl groups), R.sub.1, R.sub.2 and R.sub.3 are hydrogen atoms or lower alkyl groups, and X is an oxygen atom or a sulfur atom] and at least one pharmaceutically acceptable carrier.
    Type: Grant
    Filed: May 16, 1985
    Date of Patent: May 13, 1986
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Masayuki Teranishi, Chikara Murakata, Ikuo Matsukuma, Katsuichi Shuto, Shunji Ichikawa