Bryostatin 2 7-butyrate

To verify the tentative structural assignment, bryostatin 9 was treated with 1% hydrochloric acid in methanol at ambient temperature for 3 days. The crude product was purified using hplc (reversed phase C-18 chromatography) to yield (1 mg 0.65 mg) as major product the C-20 butyrate minus the C-7 acetyl group. The hydrolysis product was found to be identical with the principal acid-catalyzed cleavage product from bryostatin 8. From this evidence combined with a spectral analysis, the 7-hydroxy-20-butyrate structure was assigned to the bryostatin 9 hydrolysis product and thereby structure 9 to bryostatin 9. 

---