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:
Apr. 16, 1991
Filed:
Jan. 19, 1990
Chitoshi Hatanaka, Nagaokakyo, JP;
Satoru Oi, Nara, JP;
Takeda Chemical Industries, Ltd., Osaka, JP;
Abstract
There is disclosed an improved process for substitution of the hydroxy group at 2-position of an ascorbic acid derivative according to the following reaction scheme: ##STR1## wherein R.sup.0 is hydrogen, alkyl having 1 to 6 carbon atoms, phenyl or a group of the formula ##STR2## (wherein X is two hydrogen atoms, or acetal or ketal residue); R.sup.1 is an alkyl or alkenyl group having up to 22 carbon atoms which may be substituted with phenyl or alkoxy having 1 to 22 carbon atoms; Y is halogen or optionally substituted sulfonyloxy; R is hydrogen, or primary, secondary or tertiary alkyl having 1 to 10 carbon atoms; and Z is an alkali metal or an alkali earth metal. There is also disclosed hydrolysis of the following scheme: ##STR3## wherein R.sup.1 is as defined above; and X is acetal or ketal residue.