Back to results
US 5,705,650 AGranted
Process for preparing 1,2,4-thiadiazole derivatives
AssigneeKatayama Seiyakusyo Co., Ltd.
InventorsKuniaki Tatsuta, Yasuyuki Kurita, Takashi Inagaki, Ryonosuke Yoshida
Life of this patent
Estimating the term…
Abstract
An improved process for the production of 5-amino-1,2,4-thiadiazol-3-yl-(2-(lower)-alkoxyimino)acetic acids starting from 5-substituted- or unsubstituted-3-aminoisoxazole compounds is disclosed herein. The title compounds are useful as acylating agents for the production of 7-acylaminocephalosporins.
Claims1
A process for production of 1,2,4-thiadiazolylacetic acid compound of the formula:
- ##STR33## wherein R.sup.1 is lower alkyl, and R.sup.2 is lower alkoxy, phenoxy, benzyloxy, lower alkyl and phenyl optionally substituted by nitro or halogen, which comprises reacting an isoxazole of the formula:
- ##STR34## with an isothiocyanate of the formula:
- SCN--COR.sup.2
- at 0.degree.-10.degree. C. in tetrahydrofuran or acetonitrile and subjecting to rearrangement reaction in a reaction system without any base to give the compound (II).
1 more element
Dependencies are inferred from the claim text.