Abstract
Four new ceramides (1-4) were isolated from the sponge Monanchora clathrata, along with four epidioxysterols (5-8), two sterols (9, 10), uracil (11), and three triglycerides (12-14). All compounds were isolated for the first time from the genus Monanchora, also this is the first time for isolation and identification of compounds 5-8, and the ceramide moieties from the family Crambeidae. Acetylation of compounds (5-8) yielded two new chemically modified compounds (15, 16), in addition to the known 17, 18. Their chemical structures were elucidated using a combination of spectroscopic methods, including extensive 1D and 2D NMR, IR, HRESIMS, and GC/MS. The configuration of compounds 1-4 were assigned as 2S,3S,4R,2'R based on the modified Mosher's reaction, optical rotation measurements and spectroscopic data comparison. The compounds were evaluated for their, cytotoxic, antiprotozoal, antimicrobial, and antimalarial potentials. Compound 1 showed remarkable cytotoxicity against MES-SA, MCF-7, and HK-2 cell lines with IC50 values of 3.29, 17.95 and 4.45 mu M, respectively.