[2] Pristinamycin IIA structure was determined by chemical and instrumental techniques, including X-ray crystallography.

[2][3] Pristinamycin IIA is of interest from a biosynthetic viewpoint because it contains the unusual dehydroproline and oxazole ring systems.

[2] The only experimental evidence bearing on the formation of the oxazole ring is found in work on the biosynthesis of the alkaloid annuloline.

[2][4] Pristinamycin IIA biosynthesis is presumed to proceed through the acetate pathway and was determined through the feeding of 3H and 13C precursors to Streptomyces virginiae strain PDT-30.

[2] With this data and the known incorporation of proline, methionine, serine, and glycine into the antibiotic along with the assumption that carbon atoms 1, la, lb, and 2 are derived from valine or isobutyric acid, allows for a tentative pathway for the biosynthesis of Pristinamycin IIA to be deduced.