305371-63-5

Upstream product

• 203126-90-3 (3S,4S,5R)-3,5-bis[(tert-butyldimethylsilyl)oxy]-4-methyloct-1-en-7-yne 
• 305371-62-4 (20R)-De-A,B-8-bromomethylene-24,26,27-trihomo-22-oxacholestan-25-ol 
• 1113-00-4 4-ethyl-hexane-1,4-diol 
• 305371-61-3 (20R)-De-A,B-8β,25-bis[(tert-butyldimethylsilyl)oxy]-24,26,27-trihomo-22-oxacholestane 
• 305371-59-9 toluene-4-sulfonic acid 4-(tert-butyl-dimethyl-silanyloxy)-4-ethyl-hexyl ester 
• 125573-88-8 Toluene-4-sulfonic acid 4-ethyl-4-hydroxy-hexyl ester 
• 305371-60-2 3-ethyl-6-iodohexan-3-ol tert-butyldimethylsilyl ether 
• 147725-65-3 (20R)-De-A,B-24,26,27-trihomo-25-hydroxy-22-oxacholestane-8-one 
• 171231-49-5 (20R)-De-A,B-24,26,27-trihomo-22-oxacholestane-8β,25-diol 

Relevant academic research and scientific papers

Highly potent cell differentiation-inducing analogues of 1α,25-dihydroxyvitamin D3: Synthesis and biological activity of 2-methyl-1,25-dihydroxyvitamin D3 with side-chain modifications

Eight 2-methyl substituted analogues of 20-epi-22R-methyl-1α,25-dihydroxyvitamin D3 (5) and 20-epi-24,26,27-trihomo-22-oxa-1α,25-dihydroxyvitamin D3 (6: KH-1060) were convergently synthesized. Preparation of the CD-ring portions with modified side chains of 5 and 6, followed by palladium-catalyzed cross-coupling with the A-ring enyne synthons (20a-d), (3S,4S,5R)-, (3S,4R,5R)-, (3S,4S,5S)- and (3R,4R,5S)-3,5-bis[(tert-butyldimethylsilyl)oxy]-4-methyloct-1-en-7-yne, afforded two sets of four A-ring stereoisomers of 20-epi-2,22-dimethyl-1,25-dihydroxyvitamin D3 (7a-d) and 20-epi-24,26,27-trihomo-2-methyl-22-oxa-1,25-dihydroxyvitamin D3 (8a-d). The biological profiles of the hybrid analogues were assessed in terms of affinity for vitamin D receptor (VDR) and HL-60 cell differentiation-inducing activity in comparison with the natural hormone. The combined modifications of the A-ring at the 2-position and the side chain yielded analogues with high potency.