Synthesis of the C1–C13 Segment of Poecillastrin C

Abstract

A stereoselective synthesis of the C1–C13 segment of poecillastrin C has been achieved. The C1–C4 moiety was derived from diallyl l-tartrate, and the amide group at the C3 position was constructed by means of a traceless Staudinger reaction. The C1–C13 segment was submitted to model studies, including esterification with a bulky alcohol at the C1 position and Stille coupling with vinyl iodide at the C13 position. The reactivity of the C1 position was affected by the neighboring C2-protective group. When the C2 hydroxy group was protected as a TBS ether, the C1 carboxylic acid did not undergo esterification with a bulky secondary alcohol, whereas the p-methoxybenzylidene N,O-acetal afforded a 2,4-dimethyl-3-pentyl ester. Stille coupling of the C1–C13 segment with 1-iodohept-1-ene gave the southern part of the poecillastrin C macrolactam attached to simplified eastern and western parts.

Key words

stereoselective synthesis - hydroxyaspartic acid - Staudinger reaction - poecillastrin

Publikationsverlauf

Eingereicht: 22. November 2023

Angenommen nach Revision: 04. Dezember 2023

Accepted Manuscript online:
04. Dezember 2023

Artikel online veröffentlicht:
05. Januar 2024

• References and Notes

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