Patent ID: 9549958
Date: 2017-01-24
CPC Classifications: A61K,A61P,C07D

Claim:
1. A method for isolating antofine from a Cynanchum hancockianum plant, comprising the steps of: (i) mixing a powder of (ii) heating the first blend for at least 2 hours at a sufficient temperature and filtering the heated blend to obtain a first extract; (iii) concentrating the first extract by evaporation and adding an acid to the concentrated first extract to form a suspension containing a sticky material; (iv) filtering the suspension to remove the sticky material and obtain a clear solution; (v) extracting the clear solution with dichloromethane to obtain a second extract; (vi) concentrating and purifying the second extract by silica gel chromatography and eluting the concentrated purified second extract with ethyl acetate and methanol in a volume ratio of 2:5 to obtain a filtrate; (vii) recrystallizing the filtrate to obtain the isolated antofine.