Isolation and structural characterisation of five new and 14 known metabolites from the commercial starfish Archaster typicus

From the commercially available starfish Archaster typicus, five new (1-5) and 14 known (6-19) metabolites were isolated and identified. Detailed 1D and 2D NMR spectroscopic data, including H-1, C-13, DEPT, HSQC, HMBC, and NOESY, established the structures of the new metabolites as sodium 5 alpha-cholesta-9(11),24-dien-3 beta,6 alpha,20 beta-triol-23-one 3-sulphate (1), sodium 5 alpha-cholesta-9(11)-en-3 beta,6 alpha,20 beta-triol-23-one 3-sulphate (2), sodium (25R)-5 alpha-cholestane-3 beta,4 beta,6 alpha,8,14 alpha,15 beta,26-heptaol-15-sulphate (3), sodium(25R)-5cc-cholestane-3 11,6ot,8,14ot,15p,26-hexaol 15-sulphate (4), and sodium cholest-25(27)-ene-3 beta,4 beta,5 alpha,6 alpha,7 beta,8 beta,14 alpha,15 alpha,24,26-decanol 6-sulphate (5). Other spectroscopic techniques, including IR, ESI-MS, and HR-ESI-MS, were also adopted to further confirm the structures of the metabolites. These five steroids (1-5) are reported in nature for the first time. All of the steroids found in A. typicus (112) were tested for anticancer activities against MDA-MB-435 and Colo205 tumour cells. However, only sodium 5 alpha-cholesta-9(11)-en-3 beta,6 alpha,20 beta-triol-23-one 3-sulphate (2) and 27-nor-5 alpha-cholestane-3 beta,4 beta,5,6 alpha,7 beta,8,14,15 alpha,24 alpha-nonaol (6) exhibited weak activities. (C) 2010 Published by Elsevier Ltd.