Three new azaphilones produced by a marine fish-derived chaetomium globosum

Three new metabolites, chaetomugilin S, dechloro-chaetomugilin A and dechloro-chaetomugilin D, were isolated from a strain of Chaetomium globosum originally obtained from the marine fish Mugil cephalus, and their absolute stereostructures were elucidated based on the basis of spectroscopic analyses, including 1D and 2D NMR techniques and some chemical transformations. Particularly, chaetomugilins T and U are the first compouds without a chlorine atom in azaphilones isolated from this fungal strain, to date. In addition, these compounds moderately inhibited the growth of cultured P388, HL-60, L1210 and KB cell lines.