Lee Da Seul, Maejima Saki, Krische Michael J
University of Texas at Austin, Department of Chemistry, Austin, Texas 78712, United States.
Chung-Ang University, Department of Chemistry, Seoul 06974, South Korea.
Org Lett. 2023 Sep 15;25(36):6763-6766. doi: 10.1021/acs.orglett.3c02699. Epub 2023 Sep 6.
The C28-C41 side-chain of the proposed structure of neaumycin B, which encompasses a contiguous stereohextet, is prepared in 8 steps (longest linear sequence). Convergency is maximized via Williams' Felkin-Anh-selective triorganozincate-mediated vinylation of an α,β-stereogenic aldehyde. The relative stereochemical assignment of the C33-C35 stereotriad was accomplished via the C NMR analysis of the related acetonide. Relative stereochemistry of C33 carbinol and C36-C37 glycidol was determined by comparative NOE analysis of the related diastereomeric furans.
新霉素B的建议结构中包含连续立体六元组的C28 - C41侧链，通过8步反应（最长线性序列）制备而成。通过Williams的费尔金-安（Felkin-Anh）选择性三有机锌酸盐介导α,β-立体异构醛的乙烯基化反应，使收敛性最大化。C33 - C35立体三元组的相对立体化学归属通过相关缩酮的碳核磁共振（C NMR）分析完成。C33甲醇和C36 - C37缩水甘油的相对立体化学通过相关非对映体呋喃的比较性核Overhauser效应（NOE）分析确定。
