79848-93-4Relevant articles and documents
Preparation method of praziquantel
-
, (2022/03/27)
The invention relates to the technical field of medical intermediates, and provides a praziquantel preparation method which comprises the following steps: S1, adding isoquinoline, cyanide, tetrabutylammonium bromide and dichloroethane into a reactor, and dropwise adding benzoyl chloride for reaction to obtain a first-step product; s2, performing catalytic hydrogenation on the first-step product to obtain a second-step product; and S3, adding ethyl acetate into the second-step product, stirring and dissolving, adding sodium bicarbonate, dropwise adding chloroacetyl chloride, stirring and reacting to obtain a praziquantel crude product, and recrystallizing to obtain praziquantel. Through the technical scheme, the problems of long reaction process, high energy consumption and low yield in the prior art are solved.
HETEROCYCLIC COMPOUNDS AND USE THEREOF
-
Paragraph 0060-0061, (2019/03/30)
Disclosed are compounds of formula (I) below or pharmaceutically acceptable salts thereof: in which each of variables R1-R6, L, m, and n is defined herein. Also disclosed are a method for treating an opioid receptor-associated condit
METHOD FOR THE PRODUCTION OF PRAZIQUANTEL AND PRECURSORS THEREOF
-
, (2017/03/21)
The present invention provides methods of preparing Praziquantel, in particular (R)-Praziquantel and analogues thereof in a stereoselective manner. One method involves asymmetric hydrogenation of the following intermediate compound (I) and subsequent cyclization.