Ulapualides antifungal activity

The compounds isolated from the nudibranch Hexabranchus sanguineus varied with collecting location but usually included dihydrohalichondra-mide (261) and tetrahydrohalichondramide (268). Compounds 261, 263, 265, and 268 show antifungal activity and inhibit cell division in the fertilized sea urchin egg assay (218). Three cytotoxic macrolides, mycalolides A-C (269-271), were isolated from a Japanese sponge of the genus My-cale, and their structures were elucidated to be hybrids of ulapualides and halichondramide (219). 

C44H60N4O12, Mr 836.97, mp. 66-68 °C, [a]c -101° (CH3OH). A macrolide antibiotic with antifungal activity from Halichondria sponges. The structure is similar to those of ulapualides. 

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