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Revisiting a classic approach to the Aspidosperma alkaloids: an intramolecular Schmidt reaction mediated synthesis of (+)-aspidospermidine.

ABSTRACT: [reaction: see text] A total synthesis of (+)-aspidospermidine (1) is described. The key reactions used in the synthesis of this pentacyclic Aspidosperma alkaloid were a deracemizing imine alkylation/Robinson annulation sequence, a selective "redox ketalization", and an intramolecular Schmidt reaction. A Fischer indolization step carried out on a tricyclic ketone mirrored the sequence reported by Stork and Dolfini in their classic aspidospermine synthesis.

SUBMITTER: Iyengar R

PROVIDER: S-EPMC2525662 | biostudies-literature | 2005 Dec

REPOSITORIES: biostudies-literature

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Revisiting a classic approach to the Aspidosperma alkaloids: an intramolecular Schmidt reaction mediated synthesis of (+)-aspidospermidine.

Iyengar Rajesh R Schildknegt Klaas K Morton Martha M Aubé Jeffrey J

The Journal of organic chemistry 20051201 26

[reaction: see text] A total synthesis of (+)-aspidospermidine (1) is described. The key reactions used in the synthesis of this pentacyclic Aspidosperma alkaloid were a deracemizing imine alkylation/Robinson annulation sequence, a selective "redox ketalization", and an intramolecular Schmidt reaction. A Fischer indolization step carried out on a tricyclic ketone mirrored the sequence reported by Stork and Dolfini in their classic aspidospermine synthesis. ...[more]

PMID: 16355981

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