Second Generation Synthesis of C27−C35 Building Block of E7389, a Synthetic Halichondrin Analogue
作者:Yu-Rong Yang、Dae-Shik Kim、Yoshito Kishi
DOI:10.1021/ol9016589
日期:2009.10.15
A practical method is reported to synthesize E7389 C27−C35 building block 13 from 1,2-O-isopropylidene-α-d-5-deoxyglucurono-6,3-lactone (3). This synthesis relies on two key processes: (1) C34/C35-diol is introduced via asymmetric dihydroxylation with dr = 3:1, with the undesired C34-diastereomer effectively removed by crystallization of 11, and (2) the C30 PhSO2CH2 group is introduced stereoselectively