Phomacins: Three Novel Antitumor Cytochalasan Constituents Produced by a Phoma sp.

Three novel cytochalasans, phomacins A, B and C, were isolated from a fermentation broth of the fungus Phoma sp. and purified by HSCCC (high speed countercurrent chromatography) followed by HPLC. The structures were determined by 1D and 2D NMR techniques. All three compounds have shown potent inhibitory activity against the HT29 colonic adenocarcinoma cell line.