Enantioselective synthesis of 5-substituted- and 3,5-disubstituted-2-formylpyrrolidine derivatives, the key D-ring fragments of (−)-quinocarcin and (−)-10-decarboxyquinocarcin
The title synthesis was achieved starting from (S)-glutamic acid and (S)-pyroglutamic acid by featuring formation of an N-protected aminal, substitution of the methoxy group with cyanide anion, and reduction of the cyanide to an aldehyde as common key steps.
The Improved Synthesis of Enantiopure (S)-N-Arylmethyl-5-Oxoprolines
A mild procedure for the preparation of enantiopure N-alkylated (S)-(+)-5-oxoprolines 3a-r is described. The method starting from (S)-glutamic acid appears generally applicable to substrates with a wide range of substituents.
Synthetic studies on quinocarcin and its related compounds. 3.
The title synthesis was accomplished by employing each enantiomer of glutamic acid and pyroglutamic acid as chiral starting materials and featuring for