Zoanthamine (1) under bar when treated with H-2/Pd-C in EtOH yielded dihydr
ozoanthamine (2) under bar and on treatment with NaBH4 in dry dichlorometha
ne yielded deoxyzoanthamine (3) under bar and deoxytetrahydrozoanthamine (4
) under bar. The structures of (2) under bar,(3) under bar and (4) under ba
r were determined on the basis of spectral studies. Compounds (1) under bar
,(2) under bar,(3) under bar and (4) under bar were tested for their antimi
crobial activity.