Biomimetic synthesis, solerone

A biomimetic synthesis of solerone (5-oxo-4-hexanolide) 1 using both enzymatic and acid-catalyzed reactions was performed. Starting from L-glutamic acid 5-ethyl ester 2 enzymatic oxidative deamination followed by subsequent decarboxylation of the corresponding 2-oxoglutaric acid 5-ethyl ester 3 led to ethyl 4-oxobutanoate 4. In the presence of pyruvate,... 

Biomimetic Synthesis of Solerone. We applied pyruvate decarboxylase [EC 4.1.1.1] (PDC) as key enzyme for the biomimetic synthesis elucidating the formation of solerone 1 figure 1). The thiamine diphosphate depending enzyme from Saccharomyces cerevisiae is responsible for the decarboxylation of pyruvate in the course of alcoholic fermentation. After loss of carbon dioxide from 2-oxoacids the resulting aldehyde is released. Alternatively, the cofactor-bound decarboxylation product can react with a further aldehyde. By the latter acyloin condensation a new carbon-carbon bond will be formed, thus opening a biosynthetic way to a-hydroxy carbonyl compounds 11J2). 

---