Patents by Inventor Yoichi Sawa

Yoichi Sawa 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).

  • Treatment for osteoporosis
    Patent number: 4644012
    Abstract: A compound of the formula ##STR1## wherein R.sup.1 is hydrogen or hydroxy, R.sup.2 and R.sup.3 are independently hydrogen or lower alkyl and Y is carboxyl or a group convertible to carboxyl is effective for prevention or treatment of osteoporosis.
    Type: Grant
    Filed: December 20, 1984
    Date of Patent: February 17, 1987
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Masao Tsuda, Yoichi Sawa, Iwao Yamazaki
  • Production of 2,6-diaminonebularines
    Patent number: 4293690
    Abstract: Compounds of the formula ##STR1## wherein R is phenyl which may be substituted; or their acid addition salts, are produced in good yield by reacting a compound of the formula ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3, independently of one another, are hydroxyl which may be protected, which is prepared in 2 or 3 steps from 5-amino-1-.beta.-D-ribofuranosylimidazole-4-carboxamide, with a compound of the formula ##STR3## wherein R has the same meaning as defined above and X is amino which may be substituted or lower alkylthio, and, if necessary subjecting the resulting compound to a treatment for removal of protective groups on its hydroxyls.
    Type: Grant
    Filed: March 28, 1980
    Date of Patent: October 6, 1981
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Yoichi Sawa, Yoshiyuki Kawakami, Ryuji Marumoto