Salvador, Lilibeth A., Paul, Valerie J., and Luesch, Hendrik. 2010. "Caylobolide B, a Macrolactone from Symplostatin 1-Producing Marine Cyanobacteria Phormidium spp. from Florida." Journal of Natural Products 73 (9):1606-1609. https://doi.org/10.1021/np100467d
A Phormidium spp. collection from Key West, Florida, afforded caylobolide B (1), an analogue of the known macrolactone caylobolide A, previously isolated from a Lyngbya majuscula collection from the Bahamas. The planar structure of 1 was determined using NMR and MS experiments. The relative configuration for subunits C7−C9 and C25−C29 was assigned using Kishi's Universal NMR Database. Caylobolide B (1) displayed cytotoxic activity against HT29 colorectal adenocarcinoma and HeLa cervical carcinoma cells with IC50 values of 4.5 and 12.2 μM, respectively.