The utility of electrophilic sulfur transfer reactions was demonstrated by the synthesis of a diastereomer of the key macrocyclic cysteine containing component of griseoviridin. The key step involved direct reaction at the sulfur of N-(carbobenzyloxy)-S-phthalimido-L-cysteine tert-butyl ester with the anion derived from methyl 3-oxa-5 (S)-[(tert-butyldimethylsilyl) oxy] hexanoate.