Paraconulones A–G: Eremophilane Sesquiterpenoids from the Marine-Derived Fungus <i>Paraconiothyrium sporulosum</i> DL-16
Biyun Sun, Dongdong Wang, Jinwei Ren, Chaojie Wang, Pengcheng Yan, Kirk R. Gustafson, Wei Jiang
Abstract
Seven new eremophilane sesquiterpenoids, paraconulones A–G ( 1 – 7 ), along with three previously reported analogues, periconianone D ( 8 ), microsphaeropsisin ( 9 ), and 4- epi -microsphaeropsisin ( 10 ), were obtained from an EtOAc extract of the marine-derived fungus Paraconiothyrium sporulosum DL-16. The structures of these compounds were elucidated by extensive spectroscopic and spectrometric analyses, single-crystal X-ray diffraction, and computational studies. Compounds 1, 2, and 4 are the first examples of dimeric eremophilane sesquiterpenoids coupled through a C–C bond identified from microorganisms. Compounds 2 – 5, 7, and 10 showed inhibitory effects on lipopolysaccharide-induced NO production in BV2 cells, which were comparable to the positive control curcumin.