Two new antifungal cyclic lipopeptides from Bacillus marinus B-9987.

Two new cyclic lipopeptides maribasins A (1) and B (2) were isolated from the fermentation broth of the marine microorganism Bacillus marinus B-9987 isolated from Suaeda salsa in Bohai coastline of P. R. China. Both structures were established to be cyclo (D-Pro-L-Gln-L-Asn-L-Ser-D-Asn¹-D-Tyr-D-Asn²-D-β-aminoisopentadecanoic acid) (1) and cyclo (D-Pro-L-Gln-L-Asn-L-Ser-D-Asn¹-D-Tyr-D-Asn²-D-β-aminoanteisopentadecanoic acid) (2) by spectroscopic analysis and exhibited broad-spectrum activity against phytopathogens by the antifungal bioassay.