Biosynthetic studies on virginiae butanolide A, a butyrolactone autoregulator from Streptomyces. Part 2. Preparation of possible biosynthetic intermediates and conversion experiments in a cell-free system

Virginiae butanolide A 1 is one of the virginiamycin-inducing factors and has a 2,3-disubstituted butanolide skeleton which is common to other signal molecules in Streptomyces. To investigate the biosynthetic pathway of 1, possible intermediates have been synthesized. Conversion experiments with these intermediates in a cell-free system showed that the ester 11 was a biosynthetic intermediate of 1.