Chemical Studies on the Cerebrosides from the Marine-Derived Fungus Aspergillus sp. and their Biological Activities

Abstract

Abstract

Marine derived fungi have been a rich source of structurally novel and pharmacologically active secondary metabolites. With the aim to search for new bioactive compounds, we have focused on our attention to marine-derived fungi. The secondary metabolites were obtained from combining the modern knowlwdge of microorganism and chemical techniques in culture, extraction, isolation, and prification. The total structure of secondary metabolites and thir biological activities have been investigated and the results are as follows: 1. Cerebroside C (1) was isolated from mycelium extract of the marine-derived fungus Aspergillus sp. (MFA500). The structure and absolute stereochemistry of the coumpound were assigned by specytoscopic methods. The data from FAB-MS indicated the molecular formula of the compound as C43H81NO9. Compound 1 exhibited 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) activity with IC50 valule of 45.6 μM.

Cerebroside C (1)

2. The same fraction of Aspergillus sp. (MF500) yielded a metabolite, cerebroside D (2). The data from FAB-MS indicated the molecular formula of the compound as C43H79NO9. The molecular structure of cerebroside D (2) has been elucidated by 1D and 2D NMR data analysis including COSY, HMQC and HMBC. Cerebroside D (2) exhibited 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) activity with IC50 valules of 47.6 μM. Cerebroside D (2)