SULFUR-CONTAINING POLYBROMOINDOLES FROM THE RED ALGA LAURENCIA BRONGNIARTII

Article abstract of DOI:10.1016/S0040-4020(01)89191-2

Six new polybromoindoles (9-14) have been isolated from the red alga Laurencia brongniartii.Two were optically active sulfoxides, the itomanindole A (12) and B (13) and one was a bisindole (14).The structures of 12 and 14 were elucidated by X-ray analysis.The sulfoxides 12 and 13 were readily converted with diazomethane to the corresponding N-methyl derivatives.Treatment with acetic anhydryde at room temperature gave the same indolenine (24) as the major product.