Spiroarthrinols a and B, two novel meroterpenoids isolated from the spongederived fungus Arthrinium sp

Chemical investigation of the sponge derived fungus Arthrinium sp. following fermentation on solid rice medium led to the isolation of two new meroterpenoidal alcohols spiroarthrinols A (1) and B (2) together with eighteen known compounds (3-20). The structures and relative configuration of the new compounds were unambiguously determined based on HRESIMS and extensive 1D and 2D NMR spectroscopic analyses. In addition, a plausible biosynthetic pathway for the new compounds spiroarthrinols A (1) and B (2) was postulated encompassing a mixed polyketide/terpenoid pathway. When assessed for their antiproliferative activity against Caco-2 cell lines, none of the isolated compounds showed significant cytotoxicity.