Topsentiasterol sulfates with novel iodinated and chlorinated side chains from the marine sponge Topsentia sp.

Three new marine polar steroids, the first chlorine-containing steroid sulfate (1), topsentiasterol sulfate F (2) and the first natural iodinated steroid (3) have been isolated from the marine sponge Topsentia sp. The structures of 1-3 were elucidated using NMR and HRESIMS as well as by chemical correlation of 1 with previously known topsentiasterol sulfate D. Compound 1 proved to be an effective inhibitor of endo-1,3-β-d-glucanase from the marine mollusc Spisula sachalinensis.