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Published on: September 28, 2022
Synthesis of the C28-C41 Side Chain of (Proposed) Neaumycin B: A Contiguous Stereohextet
Da Seul Lee1,2, Saki Maejima1, Michael J Krische1
1University of Texas at Austin, Department of Chemistry, Austin, Texas 78712, United States.
Abstract:
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 13C 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.
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