Patents by Inventor Naoki Machida, deceased

Naoki Machida, deceased 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).

  • Tetrahydroxanthone derivatives
    Patent number: 4290954
    Abstract: A tetrahydroxanthone derivative represented by the general formula: ##STR1## wherein R is a hydrogen atom, a hydroxyl, cyano, lower alkyl, lower alkoxy, lower acyloxy, benzoyloxy or tetrazolyl group, or ##STR2## (R.sub.3 is a hydrogen atom, R.sub.4 is a hydrogen atom, a phenyl group which may be optionally substituted, or a tetrazolyl group; or R.sub.3 and R.sub.4 commonly form a ring together with the adjacent nitrogen atom and another nitrogen atom or an oxygen atom); R.sub.1 is a hydrogen or halogen atom, a lower alkyl, cyano, carboxyl or tetrazolyl group, or ##STR3## (R.sub.5 is a hydrogen atom, R.sub.6 is a phenyl group which may be optionally substituted, or a tetrazolyl group; or R.sub.5 and R.sub.6 commonly form a ring together with the adjacent nitrogen atom and an oxygen atom); and R.sub.2 is a hydrogen or halogen atom, or a lower alkyl group; with the proviso that neither R nor R.sub.1 is a hydrogen atom; when R is --CONH.sub.2, R.sub.1 and R.sub.
    Type: Grant
    Filed: October 30, 1979
    Date of Patent: September 22, 1981
    Assignee: Kowa Company Limited
    Inventors: Kazuhiro Onogi, Hisashi Kunieda, Kiyoshi Kawamura, Masami Shiratsuchi, Masahiko Nagakura, Naoki Machida, deceased, by Takayasu Miwa, heir