First Total Synthesis of the Kikai Island Polybrominated C3′–N1 Bisindole Alkaloid by a Directed Metalation Strategy

The first total synthesis of one out of four Kikai Island polybrominated C3'-N1 bisindole alkaloids from red alga <i>Laurencia brongniartii</i> is described. The key steps involve both dehydration of <i>trans</i>-hemiaminal and a C2'-methylthiolation of bisindole using dimethyl disulfide through directed metalation, followed by C3-methylthiolation using a <i>N</i>-SMe succinimide reagent.