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:
Aug. 16, 1994
Filed:
Apr. 24, 1992
Applicant:
Inventors:
Assignee:
Genelabs Technologies, Inc., Redwood City, CA (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
549298 ;
Abstract
A method of preparing a 4'-0-demethy-4.beta.-NHR podophyllotoxin, where R is an aryl or dialkyl amino alkyl group, is disclosed. The method includes reacting H.sub.2 NR under basic conditions with a mixture of .alpha. and .beta. epimers of 4'-0-demethyl-4-bromo-podophyllotoxin, to form an epimeric mixture of the 4'-0-demethyl-4-NHR-podophyllotoxin compounds, removing acidic impurities which bind to silica gel in a dichloromethane solvent, and crystallizing 4'-0-demethyl-4.beta.-NHR-podophyllotoxin from its .alpha. epimer.
Choy, William. (1994). Preparation of 4.beta.- amino podophyllotoxin compounds (U.S. Patent No. 5338867). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/5338867
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile