Patents by Inventor Kenji Hirai

Kenji Hirai 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: 6090946
    Abstract: The present invention provides an industrial process for efficiently preparing a 3-(substituted phenyl)-5-isopropylidene-1,3-oxazolidine-2,4-dione derivative having a potent herbicidal activity without using phosgene or the like. The present invention relates to a process for preparing a 3-(substituted phenyl)-5-alkylidene-1,3-oxazolidine-2,4-dione derivative represented by general formula (III), which comprises reaction of an N-(substituted phenyl)carbamate represented by general formula (I) with a 2-hydroxy-3-alkenoate represented by-general formula (II) or with a 3-alkoxy-2-hydroxyalkanoate represented by general formula (IV): ##STR1## (wherein Ar is a substituted phenyl group, R.sup.1 is an alkyl group having a carbon number of from 1 to 6, R.sup.2 and R.sup.3 are independently hydrogen atoms or alkyl groups having carbon numbers of from 1 to 12, and R.sup.4 and R.sup.5 are independently alkyl groups having carbon numbers of from 1 to 6).
    Type: Grant
    Filed: December 15, 1997
    Date of Patent: July 18, 2000
    Assignees: Sagami Chemical Research Center, Kaken Pharmaceutical Co., Ltd
    Inventors: Kenji Hirai, Katsuyuki Masuda, Tomoyuki Yano, Ryuta Ohno, Tomoko Matsukawa, Kiyomi Imai, Natsuko Okano, Tomoko Yoshii, Takehito Mouri
  • Patent number: 5886211
    Abstract: 2-(Halomethyl)phenylacetic acid esters (3) which are useful as intermediates for producing agricultural fungicides are produced efficiently and conveniently by reacting a 3-isochromanone derivative (1) with a hydrogen halide and an alcohol or reacting (1) with a halomethyl alkyl ether and then reacting the product with an alcohol in the presence of a base. The starting compound, 3-isochromanone (1), is produced in good yield by reacting an .alpha.,.alpha.'-o-xylene dihalide (4) with carbon monoxide and water in an organic solvent in the presence of a palladium catalyst and an inorganic base and then treating the product with an acid.
    Type: Grant
    Filed: March 18, 1998
    Date of Patent: March 23, 1999
    Assignees: Sagami Chemical Research Center, Iharanikkei Chemical Industry Co., Ltd
    Inventors: Kenji Hirai, Katsuyuki Masuda, Yoshihiro Takao, Masahide Sugiyama, Yukio Ono, Masahumi Matsuzawa
  • Patent number: 5883049
    Abstract: This invention provides with novel hydantoin derivatives, processes for preparing them, and herbicides containing said derivatives as active ingredient.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: March 16, 1999
    Assignees: Sagami Chemical Research Center, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Tomoyuki Yano, Natsuko Okano, Sadayuki Ugai, Osamu Yamada
  • Patent number: 5639915
    Abstract: Industrial process for the efficient production of aniline derivatives which are important intermediates for the manufacture of oxazolidinedione derivatives and tetrahydrophthalimide derivatives which are useful as active ingredients of herbicides. The process starts from 2,4-dihalo-5-aminophenol or bis(2,4-dihalo-5-aminophenyl)carbonate and selectively cycloalkylates or alkynylates the hydroxy group without protecting the amino group, whereby aniline derivatives having the cycloalkyloxy group or alkynyloxy group can be produced in high yield.
    Type: Grant
    Filed: March 10, 1995
    Date of Patent: June 17, 1997
    Assignees: Sagami Chemical Research Center, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Emiko Ejiri, Tomoyuki Yano, Kiyomi Aizawa
  • Patent number: 5612289
    Abstract: The invention relates to 4-imino-oxazolidine-2-one derivatives represented by the general formula (1): ##STR1## and a process for producing said compounds by reacting aryl isocyanates of the general formula (2): ##STR2## with methacrolein cyanohydrin in the presence of a base, as well as a herbicide containing said compounds as an active ingredient; it also relates to a process for producing oxazolidinedione derivatives useful as herbicides by hydrolyzing said compounds.
    Type: Grant
    Filed: July 8, 1996
    Date of Patent: March 18, 1997
    Assignees: Sagami Chemical Research Center, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Tomoko Matsukawa, Tomoyuki Yano, Katsuyuki Masuda, Tomoko Yoshii, Takehito Mouri, Sadayuki Ugai, Osamu Yamada
  • Patent number: 5591406
    Abstract: An automatic exhaust gas analyzer for analyzing an exhaust gas of an internal combustion engine. The analyzer includes: a) plural analyzing units; b) two independent gas lines provided in each of the plural analyzing units; c) a gas-chromatographic column provided in each of the gas lines; d) a gas-chromatographic detector connected with the column in each of the gas lines; and e) a signal communication network interconnecting the gas-chromatographic detectors. Exhaust gas and the background gas are sampled at each stage of a predetermined run cycle, and are provided immediately to the two independent gas lines of the plurality of analyzing units respectively. Then the exhaust gas and background gas are analyzed in parallel in each of the plurality of analyzing units, which facilitates equalizing the measurement conditions of the two gases and the background correction of the measurement results of the exhaust gas can be made at high precision.
    Type: Grant
    Filed: September 13, 1995
    Date of Patent: January 7, 1997
    Assignees: Shimadzu Corporation, Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Kenji Hirai, Akira Aono, Shinya Tsuneda, Hirokazu Matsumoto, Yuji Yamashita, Hisayoshi Tanaka, Takanori Shiina, Haruko Kaburagi
  • Patent number: 5554581
    Abstract: The present invention relates to 3,4,5,6-tetrahydrophthalamide derivatives and 3,4,5,6-tetrahydroisophthalimide derivatives having excellent effects as effective active ingredients of herbicides, and processes for preparing the same, and provides the compounds having a more efficient herbicidal activity, and efficient and industrial processes for the preparation thereof.More specifically, the tetrahydrophthalimide derivative obtained by reacting a halogen-substituted 5-cycloalkyloxyaniline derivative with a 3,4,5,6-tetrahydrophthalic anhydride, or the tetrahydroisophthalimide derivative of the present invention is reacted with various types of amines to prepare a tetrahydrophthalamide derivative represented by the general formula (I): ##STR1## These tetrahydrophthalamide derivatives and the tetrahydroisophthalimide derivatives exhibit excellent herbicidal activities in the soil treatment in the paddy field and field and the stem-foliar treatment.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: September 10, 1996
    Assignees: Sagami Chemical Research Center, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Tomoko Matsukawa, Tomoyuki Yano, Emiko Ejiri, Kiyomi Aizawa, Koichi Shikakura, Tomoko Yoshii, Sadayuki Ugai, Osamu Yamada, Shigeki Kishi
  • Patent number: 5506190
    Abstract: The present invention relates to 3,4,5,6-tetrahydrophthalamide derivatives and 3,4,5,6-tetrahydroisophthalimide derivatives having excellent effects as effective active ingredients of herbicides, and processes for preparing the same, and provides the compounds having a more efficient herbicidal activity, and efficient and industrial processes for the preparation thereof.More specifically, the tetrahydrophthalimide derivative obtained by reacting a halogen-substituted 5-cycloalkyloxyaniline derivative with a 3,4,5,6-tetrahydrophthalic anhydride, or the tetrahydroisophthalimide derivative of the present invention is reacted with various types of amines to prepare a tetrahydrophthalamide derivative represented by the general formula (I): ##STR1## These tetrahydrophthalamide derivatives and the tetrahydroisophthalimide derivatives exhibit excellent herbicidal activities in the soil treatment in the paddy field and field and the stem-foliar treatment.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: April 9, 1996
    Assignees: Sagami Chemical Research Center, Kaken Pharmaceutical Co. Ltd.
    Inventors: Kenji Hirai, Tomoko Matsukawa, Tomoyuki Yano, Emiko Ejiri, Kiyomi Aizawa, Koichi Shikakura, Tomoko Yoshii, Sadayuki Ugai, Osamu Yamada, Shigeki Kishi
  • Patent number: 5464811
    Abstract: A benzene derivative substituted with a heterocyclic ring represented by the general formula: ##STR1## wherein R represents a cycloalkyl group having 3 to 8 carbon atoms, X represents a halogen atom, and Z represents ##STR2## in which said cycloalkyl group may be substituted with an alkyl group having 1 to 6 carbon atoms, a process for preparing the same, and a herbicidal agent comprising the above compound as an active ingredient are disclosed. The compound has an excellent effect in that the compound exhibits a markedly high herbicidal effect on weeds in the field and the paddy field at a low dose and yet exhibits markedly low noxious effects on main crops.
    Type: Grant
    Filed: March 24, 1995
    Date of Patent: November 7, 1995
    Assignees: Sagami Chemical Research Center, Chisso Corporation, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Mitsuo Yamashita, Tomoko Tateno, Emiko Ejiri, Kikuko Harasawa, Yuichi Onji, Sadayuki Ugai, Shoin Nagato
  • Patent number: 5424277
    Abstract: A benzene derivative substituted with a heterocyclic ring represented by the general formula: ##STR1## wherein R represents a cycloalkyl group having 3 to 8 carbon atoms, X represents a halogen atom, and Z represents ##STR2## in which said cycloalkyl group may be substituted with an alkyl group having 1 to 6 carbon atoms, a process for preparing the same, and a herbicidal agent comprising the above compound as an active ingredient are disclosed. The compound has an excellent effect in that the compound exhibits a markedly high herbicidal effect on weeds in the field and the paddy field at a low dose and yet exhibits markedly low noxious effects on main crops.
    Type: Grant
    Filed: May 6, 1992
    Date of Patent: June 13, 1995
    Assignees: Sagami Chemical Research Center, Chisso Corporation, Kaken Pharmaceutical Co.
    Inventors: Kenji Hirai, Mitsuo Yamashita, Tomoko Tateno, Emiko Ejiri, Kikuko Harasawa, Yuichi Onji, Sadayuki Ugai, Shoin Nagato
  • Patent number: 5407023
    Abstract: A traction control system for a vehicle controls the torque transmitted to the road surface so that the amount of slip of the driving wheels converges on a target value when the amount of slip of the driving wheels exceeds a predetermined threshold value. When the vehicle is making a turn, the amounts of slip of the driving wheels are calculated and the calculated amounts of slip are corrected with correction values for correcting the amounts of slip of the inner and outer driving wheels taking into account the difference between the wheel speed of the inner driving wheel and that of the outer driving wheel during turning. The correction values are calculated on the basis of the actual radius of turn and the vehicle speed which are calculated on the basis of the wheel speeds of the driven wheels detected by the wheel speed detecting means.
    Type: Grant
    Filed: January 26, 1994
    Date of Patent: April 18, 1995
    Assignee: Mazda Motor Corporation
    Inventors: Tetsuhiro Yamashita, Kenji Hirai
  • Patent number: 5391807
    Abstract: Disclosed are fluorobenzene derivatives, which are important intermediates for producing herbicidal oxazolidinedione derivatives, and methods of producing them. The fluorobenzene derivatives include compounds of a formula (11): ##STR1## where X is a halogen atom, R.sup.3 is a nitro, amino or isocyanato group or R.sup.1 OCONH, and R.sup.1 is an alkyl or phenyl group. Via the intermediates of the invention, oxazolidinedione derivatives can be produced with high yield.
    Type: Grant
    Filed: May 18, 1994
    Date of Patent: February 21, 1995
    Assignees: Sagami Chemical Research Center, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Tomoyuki Yano, Mitsuo Yamashita, Emiko Ejiri, Tomoko Tateno, Kiyomi Aizawa
  • Patent number: 5344953
    Abstract: Disclosed are fluorobenzene derivatives, which are important intermediates for producing herbicidal oxazolidinedione derivatives, and methods of producing them. The fluorobenzene derivatives include compounds of a formula (11): ##STR1## where X is a halogen atom, R.sup.3 is a nitro, amino or isocyanato group or R.sup.1 OCONH, and R.sup.1 is an alkyl or phenyl group. Via the intermediates of the invention, oxazolidinedione derivatives can be produced with high yield.
    Type: Grant
    Filed: November 3, 1993
    Date of Patent: September 6, 1994
    Assignees: Sagami Chemical Research Center, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Tomoyuki Yano, Mitsuo Yamashita, Emiko Ejiri, Tomoko Tateno, Kiyomi Aizawa
  • Patent number: 5281742
    Abstract: Disclosed are fluorobenzene derivatives, which are important intermediates for producing herbicidal oxazolidinedione derivatives, and methods of producing them. The fluorobenzene derivatives include compounds of a formula (11): ##STR1## where X is a halogen atom, R.sup.3 is a nitro, amino or isocyanato group or R.sup.1 OCONH, and R.sup.1 is an alkyl or phenyl group. Via the intermediates of the invention, oxazolidinedione derivatives can be produced with high yield.
    Type: Grant
    Filed: January 21, 1992
    Date of Patent: January 25, 1994
    Assignees: Sagami Chemical Research Center, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Tomoyuki Yano, Mitsuo Yamashita, Emiko Ejiri, Tomoko Tateno, Kiyomi Aizawa
  • Patent number: 5198013
    Abstract: A benzoxazinone compound represented by the formula (I): ##STR1## wherein R.sup.1 represents a hydrogen atom or an alkyl group, and R.sup.2 represents a hydrogen atom, an alkyl group, a cyanoalkyl group, an alkenyl group, an alkynyl group or an aralkyl group; a process for preparing the same; and a herbicidal composition comprising the benzoxazinone compound as an active component are disclosed. The above benzoxazinone compounds exhibit a high selectivity for useful crop plants and a strong herbicidal activity with respect to various noxious weeds.
    Type: Grant
    Filed: January 25, 1989
    Date of Patent: March 30, 1993
    Assignees: Sagami Chemical Research Center, Chisso Corporation, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Atsuko Fujita, Hiroshi Sato, Hiroaki Hirose, Masahiro Yokota, Shoin Nagato
  • Patent number: 5100457
    Abstract: An oxazolidinedione compound represented by the formula (I): ##STR1## wherein R.sup.1 represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a cycloalkyl group having 3 to 5 carbon atoms, an alkenyl group having 3 to 5 carbon atoms, an alkynyl group having 3 to 5 carbon atoms or an alkoxycarbonyl group having 1 or 2 carbon atoms in the alkyl moiety thereof, R.sup.2 represents an alkyl group having 3 to 5 carbon atoms or a cycloalkyl group having 3 to 5 carbon atoms, and X represents a chlorine atom or a fluorine atom; a process for preparing the same; and a herbicidal composition comprising the oxazolidinedione compound as an active component are disclosed. The above oxazolidinedione compounds exhibit a high selectivity for useful crop plants and a strong herbicidal activity with respect to various noxious weeds.
    Type: Grant
    Filed: January 3, 1991
    Date of Patent: March 31, 1992
    Assignees: Sagami Chemical Research Center, Chisso Corporation, Kaken Pharmaceutical Co., Ltd.
    Inventors: Kenji Hirai, Atsuko Fujita, Hiroshi Sato, Hiroaki Hirose, Masahiro Yokota, Shoin Nagato
  • Patent number: 5053557
    Abstract: A process is disclosed for preparing 2-chloro-4-fluorophenol which comprises chlorinating 4-fluorophenol with a chlorinating agent in the presence of water. The process according to the present invention has advantages in that the chlorination can be carried out using inexpensive reagents without requiring the use of particular apparatus and under mild conditions, and the desired product can be obtained in good yields and with high selectivity. 2-Chloro-4-fluorophenol obtained in the present invention is useful as a starting material for producing various pharmaceutical agents and agricultural agents.
    Type: Grant
    Filed: September 6, 1990
    Date of Patent: October 1, 1991
    Assignee: Sagami Chemical Research Center
    Inventors: Kenji Hirai, Mitsuo Yamashita
  • Patent number: 5028738
    Abstract: There is a process for producing 2-oxo-3-aromatic carboxylic acid derivatives which comprises reacting aromatic pyruvic acid derivatives with electrophilic compounds in the presence of bases in a protic solvent. According to this process, 2-oxo-3-aromatic carboxylic acid derivatives which can be easily converted to aromatic amino acid derivatives or 2-aromatic carboxylic acid derivatives as important synthetic intermediates of medicines and agricultural chemicals can be produced in good yields with high selectivity.
    Type: Grant
    Filed: May 2, 1990
    Date of Patent: July 2, 1991
    Assignee: Sagami Chemical Research Center
    Inventors: Kenji Hirai, Kazumi Nakamura, Atsuko Fujita
  • Patent number: 5024692
    Abstract: A herbicidal composition comprising at least one oxazolidinedione derivative expressed by the following formula: ##STR1## (wherein R.sup.1, R.sup.2 and R.sup.3 independently denote hydrogen atoms, halogen atoms, nitro groups, alkyl groups, alkoxy groups, alkenyloxy groups, alkynyloxy groups or cycloalkyloxy groups; R.sup.4 and R.sup.5 independently denote hydrogen atoms, alkyl groups or aryl groups or may be combined with each other to form a polymethylene chain; and said alkyl groups, alkoxy groups, alkenyloxy groups, alkynyloxy groups, cycloalkyloxy groups and aryl groups may be substituted); and at least one organic phosphorus herbicide, as active ingredients.
    Type: Grant
    Filed: July 7, 1989
    Date of Patent: June 18, 1991
    Assignees: Kaken Pharmaceutical Co., Ltd., Sagami Chemical Research Center, Chisso Corporation
    Inventors: Shoin Nagato, Ryusuke Taguchi, Kenji Hirai, Hiroaki Hirose, Masahiro Yokota
  • Patent number: 4983751
    Abstract: Disclosed are novel oxazolidinedione derivatives expressed by the following formula: ##STR1## (R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 being defined in the specification), a method of producing the derivatives and herbicides containing the derivatives as an active ingredient. Carbonate esters which are intermediates in the method of producing the oxazolidinedione derivatives are also disclosed.These novel derivatives exhibit excellent weed-killing activity for harmful weeds and low phytotoxicity for crops.
    Type: Grant
    Filed: January 31, 1989
    Date of Patent: January 8, 1991
    Assignees: Sagami Chemical Research Center, Chisso Corporation, Kaken Pharmaceutical Co. Ltd.
    Inventors: Kenji Hirai, Takamasa Futikami, Atsuko Murata, Hiroaki Hirose, Masahiro Yokota, Shoin Nagato