71496-86-1Relevant articles and documents
Enantioselective catalytic approach to the C23–C28 subunit of 24α-methyl steroids
Yakimchyk, Viktoryia S.,Kazlova, Volha V.,Hurski, Alaksiej L.,Savchenko, Rimma G.,Kostyleva, Svetlana A.,Zhabinskii, Vladimir N.,Khripach, Vladimir A.
, p. 82 - 90 (2019/05/24)
Enantioselective synthesis of C23–C28 subunit of campestane steroids based on catalytic methods is reported. The synthesis was started from (S)-2-isopropyl-4-nitrobutan-1-ol, which is easily accessible by the reaction between isovaleraldehyde and nitroethylene catalyzed by only 2% of (S)-trimethylsilyldiphenylprolinol. Removal of one “extra” carbon from the nitroalcohol was achieved by Ni-catalyzed hydrodecarboxylation of the redox-active ester intermediate. The synthesized C23–C28 fragment was attached to a steroidal core by Julia-Kocienski reaction of a steroidal aldehyde with metallated C23–C28 sulfone. The obtained product of olefination was easily transformed to a precursor of campesterol and (Z)-22-dehydrocampesterol.
[3,3]-Claisen rearrangements in 24α-methyl steroid synthesis: Application to campesterol, crinosterol, and Δ25-crinosterol side chain construction
Khripach, Vladimir A.,Zhabinskii, Vladimir N.,Konstantinova, Olga V.,Khripach, Natalya B.,Antonchick, Andrey P.,Schneider, Bernd
, p. 597 - 603 (2007/10/03)
This paper elaborates an improved synthesis of crinosterol and campesterol starting from stigmasterol. The proposed approach is based on Claisen rearrangement of Δ23-22-allylic alcohols with various configurations of the 22-hydroxy group and ge
