219906-44-2

Upstream product

• 22953-07-7 (3S,8S,9S,10R,13S,14S,Z)-17-ethylidene-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-ol 
• 219906-40-8 (Z)-3β-(tert-butyldiphenylsiloxy)pregna-5,17-diene 
• 219906-42-0 (S)-2-[(3S,8R,9S,10R,13S,14S)-3-(tert-Butyl-diphenyl-silanyloxy)-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl]-propionaldehyde 
• 219906-41-9 (S)-2-[(3S,8R,9S,10R,13S,14S)-3-(tert-Butyl-diphenyl-silanyloxy)-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl]-propan-1-ol 
• 53-43-0 dehydroepiandrosterone 
• 219906-43-1 (22S)-3β-(tert-butyldiphenylsiloxy)cholesta-5,16-dien-22-ol 

Downstream Products

• 219906-45-3 tert-Butyl-((3S,8R,9S,10R,13S,14S)-10,13-dimethyl-17-{(S)-1-[2-(3-methyl-butyl)-[1,3]dioxolan-2-yl]-ethyl}-2,3,4,7,8,9,10,11,12,13,14,15-dodecahydro-1H-cyclopenta[a]phenanthren-3-yloxy)-diphenyl-silane 
• 219906-58-8 C₇₃H₁₂₈O₁₆Si₄ 
• 145075-81-6 3β,16β,17α-trihydroxycholest-5-en-22-one 16-O-{O-[2-O-(4-methoxybenzoyl)-β-D-xylopyranosyl]-(1->3)-2-O-acetyl-β-L-arabinopyranoside} 

Relevant academic research and scientific papers

Synthesis and structural confirmation of calibagenin and saxosterol

Calibagenin and saxosterol are cholesterol-based plant steroids isolated from Calibanus hookerii and Narthecium ossifragum, respectively. To date, the configurations of their 16- and 22-hydroxy groups have not yet been determined. In this study, all the four 16,22-stereoisomers were chemically synthesized. The 1H and 13C NMR spectra were fully assigned using 2D NMR techniques, and the structures were determined unambiguously using X-ray crystallography. The H-18 and H-22 signals in the NMR spectra of the products are diagnostic for determining the configurations of the 16- and 22-hydroxy groups. A comparison of the NMR, [α]D, and mp data of the four isomers with those of natural calibagenin and saxosterol confirmed that the configurations of the 16- and 22-hydroxy groups of the former and the later are identical to 16β,22S and 16β,22R, respectively.

First total synthesis of an exceptionally potent antitumor saponin, OSW- 1

OSW-1 (1), an acylated disaccharide cholestane saponin from Ornithogalum saudersiae with exceptionally potent antitumor activity, was first synthesized from commercially available dehydroisoandrosterone, L-arabinose, and D-xylose in total 27 steps with the longest linear sequence of 14 steps and in 6% yield.