Studies on chemical constituents of Laurencia saitoi / 中国中药杂志

ABSTRACT

In order to search for bioactive natural products from marine algae, the chemical constituents of red alga Laurencia saitoi was separated by the combination of normal phase silica gel, Sephadex LH-20 column chromatography and recrystallization. Seven compounds aplysistatin (1), 5-acetoxypalisadin B (2), palisadin B (3), palisadin A (4), pacifigorgiol (5), stigmast4-en-3alpha, 6beta-diol (6), 2, 3, 5, 6-Tetrabromoindole (7), were isolated and their structures were elucidated by spectroscopic methods including 1H-NMR, 13C-NMR and MS techniques. All compounds were isolated from L. saitoi for the first time. Cytotoxicities of purified compounds were evaluated by MTT method, however, all of them were found inactive (IC50 >10 mg x L(-1).