Using various chromatography methods, three merosesquiterpenes belonging to sesquiterpene quinone type, neodactyloquinone (1), dactyloquinone D (2), and dactyloquinone C (3) together with two indole derivatives indole-3- aldehyde (4) and indole-3-cacboxylic methyl ester (5) were isolated from the methanol extract of the Vietnamese marine sponge Smenospongia cerebriformis. Their structures were determined by 1D-, 2D-NMR spectra, HR-ESI-MS and in comparison with those reported in the literature. | Vietnam Journal of Chemistry, International Edition, 55(2): 153-157, 2017 DOI: Merosesquiterpenes from marine sponge Smenospongia cerebriformis Le Thi Huyen1, Dan Thi Thuy Hang2, Nguyen Xuan Nhiem2, Bui Huu Tai2, Hoang Le Tuan Anh2, Pham Hai Yen2, Nguyen Van Dau1, Chau Van Minh2, Phan Van Kiem2* 1 Hanoi University of Science, Vietnam National University 2 Institute of Marine Biochemistry, Vietnam Academy of Science and Technology Received 31 October 2016; Accepted for publication 11 April 2017 Abstract Using various chromatography methods, three merosesquiterpenes belonging to sesquiterpene quinone type, neodactyloquinone (1), dactyloquinone D (2), and dactyloquinone C (3) together with two indole derivatives indole-3aldehyde (4) and indole-3-cacboxylic methyl ester (5) were isolated from the methanol extract of the Vietnamese marine sponge Smenospongia cerebriformis. Their structures were determined by 1D-, 2D-NMR spectra, HR-ESI-MS and in comparison with those reported in the literature. Keywords. Smenospongia cerebriformis, merosesquiterpene, sesquiterpene quinone, indole derivative. 1. INTRODUCTION . General experimental procedures Marine sponges are regarded as a rich source of secondary metabolites with chemically diverse structures and potential biological benefits. Merosesquiterpenes and indole alkaloid derivatives were found to be the main components of sponges, particularly, the genus Smenospongia. A huge variety of compounds belonging to these two chemical structure classes have been reported from sponges and possessed a broad range of interest bioactivities, such as antimalarial [1, 2], antimicrobial [1-3], anticancer [3, 4] antidepressant [5], as well as inhibition of the neuronal isozyme of nitric oxide synthase (nNOS) [6]. Herein, we report the isolation and structure determination of three merosesquiterpenes and two indole alkaloid derivatives from sponge Smenospongia cerebriformis. The 1H-NMR (500 MHz) and
