CreativeChemistry's blog

09 Mar

Doemling's Chiral Praziquantel Synthesis????

Published by CreativeChemistry

 While Doemling has published (and patented) a Ugi approach to racemic PZQ, there was also a claim in an abstract from a ASTMH meeting from December 2008 that he was to talk about a chiral synthesis (abstract below). Anyone know anything about this?
 

08 Nov

Alternative Approach to the Diamine Precursor

Published by CreativeChemistry

Subject 

Miscellaneous

 We have looked at an alternative process to generate the diamine precursor to PZQ, whose resolution is documented. The process involves reduction of the cyano-imine derived from the published reaction of THIQ with peroxide/tungstate/cyanide. Having been able to reduce 1-cyanoisoquinoline very cleanly using Pd/C we anticipated that it would be possible to do the same here. It would be important, however, to maintain acidic conditions to prevent the retro-addition of the cyanide (well documented for the 1-cyano and 1-(nitromethyl)isoquinolines with a free N-H).
 

29 Oct

Preparation of Low Cost (R)-(-)-Praziquantel

Published by CreativeChemistry

Preparation of Chiral Praziquantel

Creative Chemistry/Development
Chemicals Ltd

 
Following on from a project for the preparation of low cost
chiral mefloquine, we were asked by WHO to have a brief look at praziquantel in
order to see if we had any ideas for a low cost synthesis of the chiral
material.
 
 
Current Industrial
 Process
The first objective was to determine the process which is