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Synthetic studies on Et-743. Assembly of the pentacyclic core and a formal total synthesis.

ABSTRACT: A formal total synthesis of the potent anticancer agent Et-743 is described. The tetrahydroisoquinoline core is stereoselectively constructed using a novel radical cyclization of a glyoxalimine. Further elaboration of this core rapidly accessed the pentacyclic core of Et-743, but a mixture of regiosisomers was obtained in the key Pictet-Spengler ring closure. A known advanced intermediate in the synthesis of Et-743 was intercepted, constituting a formal synthesis of the molecule.

SUBMITTER: Fishlock D

PROVIDER: S-EPMC2736329 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

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Synthetic studies on Et-743. Assembly of the pentacyclic core and a formal total synthesis.

Fishlock Dan D Williams Robert M RM

The Journal of organic chemistry 20081201 24

A formal total synthesis of the potent anticancer agent Et-743 is described. The tetrahydroisoquinoline core is stereoselectively constructed using a novel radical cyclization of a glyoxalimine. Further elaboration of this core rapidly accessed the pentacyclic core of Et-743, but a mixture of regiosisomers was obtained in the key Pictet-Spengler ring closure. A known advanced intermediate in the synthesis of Et-743 was intercepted, constituting a formal synthesis of the molecule. ...[more]

PMID: 18687003

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