Microbial transformation of (−)-Huperzine A

Five products were yielded from the transformation of (−)-Huperzine A (1) by Streptomyces griseus CACC 200300. Their structures were determined as 16-hydroxyl huperzine A (2), 14α-hydroxyl huperzine A (3), huperzine A 8α,15α-epoxide (4), 13N-formyl huperzine A (5), and 13N-acetyl huperzine A (6) on the basis of their chemical and physical data. It is the first report on the microbial transformation of (−)-Huperzine A and would facilitate further structural modification by chemo-enzymatic method.