Patents by Inventor Tomoyuki Ishikura

Tomoyuki Ishikura 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).

  • Publication number: 20130059375
    Abstract: The present invention provides a method of producing a mammalian ES cell, including cultivating a mammalian inner cell mass in a medium containing adrenocorticotropic hormone, an FGF receptor inhibitor, an MEK activation inhibitor and a GSK3 inhibitor, and isolating a mammalian ES cell from the culture.
    Type: Application
    Filed: April 1, 2011
    Publication date: March 7, 2013
    Applicant: RIKEN
    Inventors: Haruhiko Koseki, Takanori Hasegawa, Tomoyuki Ishikura, Masashi Matsuda
  • Patent number: 4996314
    Abstract: A compound represented by the formula ##STR1## wherein R.sub.1 represents a lower alkyl group or a lower haloalkyl group; R.sub.2 represents a lower alkyl group, a lower haloalkyl group, an aralkyl group, or a group of the formula --COOR.sub.4 or --SO.sub.2 R.sub.5 in which R.sub.4 represents an aralkyl group or a substituted or unsubstituted alkyl group and R.sub.5 represents an alkyl group or a substituted or unsubstituted aryl group; and R.sub.3 represents a hydrogen atom or a carboxyl protecting group which can be easily split off. This compound is useful in the production of a 6-(disubstituted amino)carbapenem-series antibiotic.The compounds of the formula ##STR2## wherein R.sub.1 and R.sub.2 are as defined above are important intermediates for the synthesis of the compounds of formula (I) and/or the aforesaid di-(substituted amino) carbapenem-series antibiotics.
    Type: Grant
    Filed: September 19, 1988
    Date of Patent: February 26, 1991
    Assignee: Sanraku Incorporated
    Inventors: Takeo Yoshioka, Noritaka Chida, Azuma Watanabe, Yasuo Fukagawa, Tomoyuki Ishikura
  • Patent number: 4939248
    Abstract: This invention provides compounds of the formula ##STR1## wherein Y represents an acetyl, 1-hydroxyethyl or 1-fluoroethyl group, R.sub.1 represents a hydrogen atom or an easily splittable amino-protecting group, and R.sub.2 and R.sub.3 are identical or different and each represents a hydrogen atom, a lower alkyl group, a phenyl group, a benzyl group or a diphenylmethyl group, or R.sub.2 and R.sub.3 together represent a lower alkylene group; and processes for production thereof. These compounds are useful as synthesis intermediates for production of various medicines, particulary carbapenam or carbapenem antibiotics, such as a carbapenem antibiotic of the following formula which has excellent antimicrobial activity and relatively good stability to kidney dehydropeptidase.
    Type: Grant
    Filed: August 18, 1988
    Date of Patent: July 3, 1990
    Assignee: Sanraku Incorporated
    Inventors: Takeo Yoshioka, Machiko Watanabe, Yasuo Fukagawa, Tomoyuki Ishikura
  • Patent number: 4918172
    Abstract: Disclosed are anthracycline antibiotics of a formula (I): ##STR1## in which R.sup.1 and R.sup.2 are hydroxyl groups, R.sup.3 is ethyl group, R.sup.4 is methoxycarbonyl group and X represents daunosamine-rhodenose or daunosamine-deoxyfucose; orR.sup.1 and R.sup.2 are hydroxyl groups, R.sup.3 is 1-hydroxyethyl group, R.sup.4 is hydrogen atom and X represents daunosamine-rhodenose or daunosamine-deoxyfucose; orR.sup.1, R.sup.2 and R.sup.4 are hydroxyl groups, R.sup.3 is ethyl group and X represents daunosamine-rhodenose, daunosamine-deoxyfucose, rhodosamine-rhodenose, N-monomethyldaunosamine-rhodenose or N-monomethyldaunosamine-deoxyfucose; orR.sup.1 is methoxy group, R.sup.2 is hydroxyl group, R.sup.3 is ethyl group, R.sup.4 is methoxycarbonyl group and X represents daunosamine-rhodenose or daunosamine-deoxyfucose; orR.sup.1 and R.sup.4 are hydroxy groups, R.sup.2 is hydrogen atom, R.sup.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: April 17, 1990
    Assignee: Sanraku Incorporated
    Inventors: Akihiro Yoshimoto, Osamu Jodo, Yoshio Watanabe, Rokuro Okamoto, Tomoyuki Ishikura, Hiroshi Naganawa, Tsutomu Sawa, Tomio Takeuchi
  • Patent number: 4897470
    Abstract: New anthracycline antibiotics of a formula (I) are provided, which are usable as an anticancer agent ##STR1## (where R represents a hydrogen atom or a hydroxyl group). The antibiotics (I) can be produced by incubation of a dye-nonproductive or hardly dye-productive mutant strain which has an ability of converting .alpha.-citromycinone or .beta.-isorhodomycinone into the antibiotics (I), in the presence of .alpha.-citromycinone or .beta.-isorhodomycinone in a pertinent nutrient medium.
    Type: Grant
    Filed: April 6, 1987
    Date of Patent: January 30, 1990
    Assignee: Sanraku Incorporated
    Inventors: Akihiro Yoshimoto, Osamu Jodo, Yoshio Watanabe, Tomoyuki Ishikura, Tsutomu Sawa, Tomio Takeuchi, Hamao Umezawa, deceased
  • Patent number: 4853407
    Abstract: Compounds represented by formula ##STR1## wherein Y.sup.1 and Y.sup.2 are identical or different, and respectively denote benzoylamino groups or phthalimide groups. This compound is useful for inhibition of dipeptidase.
    Type: Grant
    Filed: May 20, 1988
    Date of Patent: August 1, 1989
    Assignee: Sanraku Incorporated
    Inventors: Norio Shibamoto, Takeo Yoshioka, Yasuo Fukagawa, Tomoyuki Ishikura
  • Patent number: 4812563
    Abstract: A compound represented by the formula ##STR1## wherein R.sub.1 represents a lower alkyl group or a lower haloalkyl group; R.sub.2 represents a lower alkyl group, a lower haloalkyl group, an aralkyl group, or a group of the formula --COOR.sub.4 or --SO.sub.2 R.sub.5 in which R.sub.4 represents an alkyl group or a substituted or unsubstituted aralkyl group and R.sub.5 represents an alkyl group or a substituted or unsubstituted aryl group; and R.sub.3 represents a hydrogen atom or a carboxyl protecting group which can be easily split off. This compound is useful in the production of a 6-(disubstituted amino)carbapenem-series antibiotic.
    Type: Grant
    Filed: March 10, 1987
    Date of Patent: March 14, 1989
    Assignee: Sanraku Incorporated
    Inventors: Takeo Yoshioka, Noritaka Chida, Azuma Watanabe, Yasuo Fukagawa, Tomoyuki Ishikura
  • Patent number: 4781977
    Abstract: A cyclodextrin adsorbing material composed of a water-insoluble resin substrate to which a ligand having such a size as to be included by cyclodextrin is chemically bonded via a spacer radical; a method of separating and purifying cyclodextrin from an aqueous solution containing it, which comprises bringing said aqueous solution into contact with the above adsorbing material to adsorb cyclodextrin on the adsorbing material, and subjecting the adsorbing material to a desorption treatment to recover cyclodextrin; and a method of increasing the amount of cyclodextrin yielded, which comprises carrying out a cyclodextrin-forming reaction by an enzymatic method in the presence of the above adsorbent material.
    Type: Grant
    Filed: October 31, 1986
    Date of Patent: November 1, 1988
    Assignee: Sanraku Incorporated
    Inventors: Yoshiaki Yagi, Kenichi Yamamoto, Yukio Tsuchiyama, Michikatsu Sato, Kouki Fujii, Tomoyuki Ishikura
  • Patent number: 4778883
    Abstract: An azetidinone derivative of the formula ##STR1## wherein R.sub.1 represents a formyl group, a carboxyl group, an acetyloxy group or a group of the formula ##STR2## in which R.sub.2 and R.sub.3 each represent a lower alkyl group or together represent a lower alkylene group, and Z represents a hydrogen atom or an amino-protecting group.
    Type: Grant
    Filed: February 18, 1987
    Date of Patent: October 18, 1988
    Assignee: Sanraku Incorporated
    Inventors: Takeo Yoshioka, Noritaka Chida, Azuma Watanabe, Yasuo Fukagawa, Tomoyuki Ishikura
  • Patent number: 4746734
    Abstract: Partially methylated cyclodextrins with enhanced solubility in water have an average degree of methylation of hydroxyl groups at different positions in all the glucose units involved of about 53-64% for the 2-position, about 38-51% for the 3-position and about 70-100% for the 6-position. The partially methylated cyclodextrins are prepared by reacting .beta.-cyclodextrin with more than about 30 equivalent proportions based on the .beta.-cyclodextrin of dimethyl sulfate and more than about 30 equivalent proportions of an alkali metal hydroxide, wherein the concentration of reactants is greater than 10% (wt/wt).
    Type: Grant
    Filed: February 27, 1987
    Date of Patent: May 24, 1988
    Assignee: Sanraku Incorporated
    Inventors: Yukio Tsuchiyama, Michikatsu Sato, Yoshiaki Yagi, Tomoyuki Ishikura
  • Patent number: 4734493
    Abstract: The antibiotics designated obelmycins exhibit high proliferation inhibiting action against leukemia cells and are effective as anti-cancer agents.
    Type: Grant
    Filed: April 7, 1986
    Date of Patent: March 29, 1988
    Assignee: Sanraku, Incorporated
    Inventors: Akihiro Yoshimoto, Osamu Jodo, Yoshio Watanabe, Tomoyuki Ishikura, Tsutomu Sawa, Tomio Takeuchi, Hamao Umezawa
  • Patent number: 4612372
    Abstract: Novel tylosin derivatives are represented by formula: ##STR1## wherein R represents a hydrogen atom, an acetyl group or a propionyl group; X represents a group --CO-- or --SO.sub.2 --; Y represents a fluorine atom, an acetyl group, a methanesulfonyl group, a methylthio group, a benzoyl group or a methoxy group bound to the benzyl group at the 2-position or 4-position; and Z represents a hydrogen atom or a D-mycinose residue: ##STR2## The tylosin derivatives which are antibiotics of macrolide type provide improved antibacterial activity and improved ability of absorption and excretion in vivo.
    Type: Grant
    Filed: July 12, 1985
    Date of Patent: September 16, 1986
    Assignee: Sanraku Incorporated
    Inventors: Takeo Yoshioka, Miharu Maeda, Rokuro Okamoto, Yasutaka Shimauchi, Tomoyuki Ishikura, Tsutomu Sawa, Tomio Takeuchi, Hamao Umezawa
  • Patent number: 4612371
    Abstract: Novel anthracycline antibiotics characteristic of Ring A of the anthracycline skeleton are produced by microorganisms belonging to the genus Streptomyces and are useful as anti-cancer agents.
    Type: Grant
    Filed: July 18, 1985
    Date of Patent: September 16, 1986
    Assignee: Sanraku Incorporated
    Inventors: Akihiro Yoshimoto, Shizuka Fujii, Katsuro Kubo, Tomoyuki Ishikura, Tsutomu Sawa, Tomio Takeuchi, Hamao Umezawa
  • Patent number: 4592999
    Abstract: This invention is to provide a new microbial process for producing daunomycin by a mutant strain belonging to the genus Streptomyces.
    Type: Grant
    Filed: July 18, 1983
    Date of Patent: June 3, 1986
    Assignee: Sanraku Incorporated
    Inventors: Hamao Umezawa, Tomio Takeuchi, Kageaki Kouno, Tomoyuki Ishikura, Akihiro Yoshimoto, Yukio Takatsuki, Hiroyasu Tobe
  • Patent number: 4536397
    Abstract: A group of novel depsipeptide antibiotics, neoviridogriseins I, II and III are produced by fermentation of Streptomyces sp. P8648 (FERM-P 3562; ATCC 31289). The antibiotics are highly active against Gram-positive bacteria and mycoplasmas.
    Type: Grant
    Filed: October 31, 1983
    Date of Patent: August 20, 1985
    Assignees: Sanraku-Ocean Co., Ltd., Panlabs, Inc.
    Inventors: Yasushi Okumura, Kazuhiko Okamura, Yasuo Fugakawa, Tomoyuki Ishikura, Kageaki Kouno, Joseph Lein
  • Patent number: 4528397
    Abstract: An aminocarboxylic acid derivative represented by the formula ##STR1## wherein R.sub.1 and R.sub.2, independently from each other, represent a hydrogen atom or an alkyl group which may have a substituent, and Y represents --NH-- or --S--, provided that when Y represents --NH--, at least one of R.sub.1 and R.sub.2 represents an alkyl group which may have a substituent. These compounds have excellent inhibitory activity on dipeptidase in animals, and are useful for administration in combination with carbapenem antibiotics.
    Type: Grant
    Filed: March 29, 1983
    Date of Patent: July 9, 1985
    Assignee: Sanraku-Ocean Co., Ltd.
    Inventors: Norio Shibamoto, Takeo Yoshioka, Yasuo Fukagawa, Tomoyuki Ishikura
  • Patent number: 4517127
    Abstract: A compound represented by the following formula: ##STR1## wherein R.sub.1 represents a hydrogen atom or a hydroxyl group, R.sub.2 represents a group of the formula --CH.sub.2 NO.sub.2, --CN.fwdarw.O or ##STR2## in which A represents a group of the formula ##STR3## in which R.sub.4 represents a hydrogen atom or an alkoxycarbonyl group, R.sub.5 represents a phenyl, alkoxycarbonyl or alkanoyloxymethyl group, R.sub.6 represents an alkyl group and R.sub.7 represents a phenyl, naphthyl, pyridyl, furyl or thienyl group; and R.sub.3 represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group, and a process for production thereof.
    Type: Grant
    Filed: December 9, 1983
    Date of Patent: May 14, 1985
    Assignee: Sanraku-Ocean Co., Ltd.
    Inventors: Takeo Yoshioka, Kenichi Yamamoto, Yasuo Fukagawa, Yasutaka Shimauchi, Tomoyuki Ishikura
  • Patent number: 4508648
    Abstract: Novel phosphoric ester of antibiotic OA-6129 presented by the formula ##STR1## wherein R is a hydrogen atom, hydroxyl or hydroxysulfonyloxy, and its salts and the preparation method thereof.
    Type: Grant
    Filed: September 24, 1982
    Date of Patent: April 2, 1985
    Assignee: Sanraku-Ocean Co., Ltd.
    Inventors: Katsuro Kubo, Takeo Yoshioka, Mitsuyasu Okabe, Yasuo Fukagawa, Tomoyuki Ishikura
  • Patent number: 4474945
    Abstract: New anthracycline compounds, 2-hydroxyaclacinomycin B having potent antitumor activity and lower toxicity, and a process for producing 2-hydroxyaclacinomycins A, B, and N by fermentation.
    Type: Grant
    Filed: August 6, 1982
    Date of Patent: October 2, 1984
    Assignee: Sanraku-Ocean Co., Ltd.
    Inventors: Akihiro Yoshimoto, Hiroyasu Tobe, Tomoyuki Ishikura, Hamao Umezawa, Tomio Takeuchi
  • Patent number: 4463171
    Abstract: Compounds of the following general formula ##STR1## wherein R.sup.1 and R.sup.2 represent a hydrogen atom or a lower alkanoyl group;R.sup.3 represents a hydrogen atom or the group --COCH.sub.2 R.sup.5 in which R.sup.5 represents a lower alkyl group or an aryl or pyridyl group bonded through a sulfur atom;R.sup.4 represents a methyl group which may be substituted by aryl, pyridyl, pyridylthio, hydroxyl or arylthioamino, an aryl group, a nitrile group, a 5- or 6-membered heterocyclic group having 1 to 4 hetero atoms selected from nitrogen and sulfur atoms, or a tetrahydropyranyl group which may be substituted by methoxy;A represents the group --OCO--, --OSO.sub.2 --, --O-- or --S--, or A and R.sup.4, taken together, represent a halogen atom, a nitrile group or a group of the formula ##STR2## in which R.sup.
    Type: Grant
    Filed: June 9, 1983
    Date of Patent: July 31, 1984
    Assignee: Sanraku-Ocean Co., Ltd.
    Inventors: Hamao Umezawa, Tomio Takeuchi, Kuniaki Tatsuta, Tomoyuki Ishikura, Rokuro Okamoto, Masao Yamamoto, Kohki Kiyoshima