870626-87-2

Upstream product

• 870626-48-5 [(3S,8R,9S,10R,13S,14S,16R,17S)-3-(tert-Butyl-dimethyl-silanyloxy)-16,17-dihydroxy-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-17-yl]-acetic acid dodecyl ester 
• 870626-60-1 [(3S,8R,9S,10R,13S,14S,17S)-3-(tert-Butyl-dimethyl-silanyloxy)-17-hydroxy-10,13-dimethyl-16-oxo-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-17-yl]-acetic acid dodecyl ester 
• 790224-39-4 16α-hydroxy-3β-(tert-butyldimethylsiloxy)-5-androsten-17-one 
• 870626-73-6 [(3S,8R,9S,10R,13S,14S,16S,17S)-3-(tert-Butyl-dimethyl-silanyloxy)-16,17-dihydroxy-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-17-yl]-acetic acid dodecyl ester 
• 321125-08-0 2-O-(4-methoxybenzoyl)-3,4-di-O-triethylsilyl-β-D-xylopyranosyl-(1→3)-2-O-acetyl-4-O-triethylsilyl-α,β-L-arabinopyranosyl trichloroacetimidate 

Relevant academic research and scientific papers

OSW Saponins: Facile synthesis toward a new type of structures with potent antitumor activities

OSW saponins, featuring a 16β,17α-dihydroxycholest-22-one aglycon and an acylated β-D-xylopyranosyl-(1→3)-α-L- arabinopyranosyl residue attached to the 16-hydroxyl group, have recently been discovered from a group of lily plants, which show potent antitumor activities with a novel mechanism of action. This paper describes an aldol approach to the stereoselective construction of the 16α,17α-dihydroxycholest-22-one structure from 16α-hydroxy-5-androsten-17-ones and propionates. Elaboration of the aldol adducts toward OSW-1, involving installation of the isoamyl ketone side chain, inversion of the 16-hydroxyl configuration, and selective protection of the C22-oxy function, has been explored and accomplished. In particular, the present route was found convenient for the synthesis of OSW saponin analogues with a C22-ester side chain. Thus, the 23-oxa-analogue of OSW-1 (40) was prepared starting from the industrial dehydroisoandrosterone (1) in a linear eight-step sequence and in 26% overall yield. Analogues with a variety of modified side chains were prepared, via aldol condensation with propionates of varying length, thiopropionate, and acetate (for preparation of 68-75) or via aminolysis of the 22,16-lactone 26 (for preparation of the 23-N-analogues). Cross metathesis (CM) reaction was also found feasible for modification at the final stage from C22-allyl ester 70. Valuable structure-activity relationships (SAE), together with the practical synthetic approach, have thus been provided to set a new stage for further studies on this new type of antitumor structures.