I've been working on the sulfur melt reaction, trying to optimize the reaction yield of the singly dehydrogenated product (DHP below). Many studies have been conducted, and here I'll discuss some of what I've found out.
Proton NMR assignment for PZQ has been carried out twice in the literature. Once in a review article: Analytical Profiles of Drug Substances and Excipients, 1998, 25, 463, and once in Arch. Pharm. (Weinheim), 1989, 322, 795-799. Of interest are the large differences in chemical shift between the diastereotopic protons on positions 1 and 6. Need image capture from the pdfs posted below...
The synthesis of rac-PZQ via the Pictet-Spengler route was developed by the Korean Shin Poong Pharmaceutical Company and obtains very low production costs of US¢7 per 600 mg tablet of the drug.
Project A: Development of a low-cost enantioselective synthesis of PZQ. It's an open project, like everything on TSL. Meaning?: contributors can change anything they wish on these pages. If you wish to contribute: please don't leave comments here. Instead, edit the pages below directly or leave comments.
For an inexpensive route to rac-PZQ (and potentially the enantioenriched material), the relevant starting materials (below) are required. While prices may be obtained for these from commercial catalogues, we require realistic prices of these materials on a large (ton) scale to assess whether this approach to PZQ is economically viable. The starting materials are:
InChI is great and all, but today while exploring, I found two issues that bugged me. The first arose from my simple double-checking exercise: I drew praziquantel at http://pubchem.ncbi.nlm.nih.gov/edit/ then took the InChI returned and plugged it into chemspider.com to see if it would bring up the appropriate page for PZQ (which I already knew existed). I made the mistake of leaving one of the amide nitrogens as a carbon, so my search on chemspider returned that there were no hits at all. Now, in this case that's fine, cause I messed u
