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:
Jul. 06, 1993
Filed:
Apr. 24, 1992
Applicant:
Inventor:
Yuji Tahara, Sapporo, JP;
Assignee:
Hoxan Corporation, Hokkaido, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C09J / ; C07C / ;
U.S. Cl.
CPC ...
552653 ; 568817 ; 568822 ; 568828 ; 568838 ;
Abstract
There is provided a method with which vitamin D.sub.2, vitamin D.sub.3, activated type vitamin D.sub.2, activated type vitamin D.sub.3 and their derivatives are prepared from 7,8 -dihyroxy vitamin D.sub.2, D.sub.3 or any of their derivatives by means of a reducing elimination technique involving as cyclic orthoester of a 7,8-dihydroxy compound or a thiocarbonate compound as an intermediate compound or an elimination technique utilizing a reducing metal such as titanium. The method according to the invention ensures a practical and simple synthetic process and a high yeild as compared with any existing methods for manufacturing these chemicals.