In this paper a synthetic pathway to the modified 5,10 13,14-bisfragmentation cholestane derivatives 8-14 is described. The synthesis involves introduction of the 5 alpha- and 14 alpha-hydroxyl groups in the cholestane molecule and Subsequent cleavage of the C(5)-C(10) bond in 5 alpha,14 alpha-dihydroxycholestan-3 beta-yl acetate (4) with the HgO/I-2 reagent and the C(13)-C( 14) bond in the stereoisomeric 14 alpha-hydroxy-5,10-secosteroids 5 and 6 with the Pb(OAc)(4)/I-2 reagent Complete and Unambiguous H-1 and C-13 NMR resonance assignments of the obtained secosteroids. as well as the Solution conformations of then 10- and 9-membered rings were determined by extensive analysis of 1D and 2D NMR spectral data The structures and the solid-state conformations of 5,10-secosteroids 5-7 were confirmed by X-ray analysis All diseco-compounds have a novel 5.10 13,14-disecocholestane skeleton. (C) 2009 Elsevier Ltd. All rights reserved