The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 10, 1995
Filed:
Mar. 29, 1994
Joji Nakano, Toyama, JP;
Nobuhisa Taya, Shinminato, JP;
Hisaaki Chaki, Toyama, JP;
Tetsuo Yamafuji, Toyama, JP;
Kaishu Momonoi, Shinminato, JP;
Toyama Chemical Co., Ltd., Tokyo, JP;
Abstract
This invention relates to a process for producing a compound represented by formula (6a) or (6b): ##STR1## wherein R.sup.2 represents a hydrogen atom or a hydroxyl-protecting group and R.sup.4 and R.sup.5, which may be the same or different, represents lower alkyl groups, using a compound represented by formula (2a) or (2b) obtained by preferential crystallization: ##STR2## and also to a compound represented by the following formula (7) which is an intermediate useful for producing the compound of formula (6a) or (6b): ##STR3## wherein R.sup.1 represents a group represented by formula (8): ##STR4## wherein R.sup.2 and R.sup.3 is as defined above and R.sup.3 represents a hydrogen atom, a group or a carboxyl protecting group represented by formula (9): ##STR5## or a group represented by formula (10): ##STR6## wherein R.sup.2 is as defined above.