Praziquantel synthesis request

There is a request from Mat Todd in TheSynapticLeap for contributions to the synthesis of Praziquantel, an anti-schistosomiasis medicine. Thanks to Marc for the link.

Update: ChemRefer just suggested this thesis as a previous attempt at a more efficient synthesis of praziquantel:

http://etd.fcla.edu/SF/SFE0000266/Thesis.pdf

Alternative Way of Synthesizing DOPAL

The challenge thus far has been the synthesis of 3,4-dihydroxyphenylacetaldehyde (DOPAL). I have found a new way to possibly synthesize DOPAL by first making the 3,4-methylenedioxyphenylacetaldehyde intermediate by a method found in a paper titled "Some Derivatives of 2: 3-Dihydroxynaphthalene" Authors: Howell, FH and Taylor, DA. Journal of Chemical Society, Abstracts. 4252-4256 (1956).

Following this, we can synthesize DOPAL (using the intermediate synthesized above) by a method found in a paper titled "Synthesis of a Biochemically Important Aldehyde, 3,4-dihydroxyphenylacetaldehyde" Authors: Li, SW, Spaziano, VT et al. Journal of Bioorganic Chemistry, 24, 45-50 (1998). These methods are show below.

The only drawback to this method is the authors only had a 14% yield of DOPAL

Experiments blog

I have set up a separate blog to put all experimental details for the UsefulChem project, at least for experiments done in my lab. The plan is to use about 300 posts per Blogger blog as one laboratory notebook. Each post is one experiment and open for comment.

We'll continue to use this blog to talk about syntheses and problems that we are having.

Right now Alicia, Brett and James are still working on the conversion of adrenaline to the key catechol aldehyde we will need for many of the syntheses of the diketopiperazines. We don't currently have access to NMR so we are attempting to monitor the conversion by IR and hopefully today GC-MS. We have a room full of new powerful equipment (like LC-MS) that will be available in the next few weeks so synthesis should get easier.