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Synthesis and cytotoxicity of desmethoxycallipeltin B: lack of a quinone methide for the cytotoxicity of callipeltin B.

ABSTRACT: The desmethoxy analogue of the cytotoxic, cyclic depsipeptide callipeltin B was synthesized to evaluate the role of its beta-MeOTyr residue. The IC(50) of desmethoxycallipeltin B, in which the beta-MeOTyr residue was replaced by d-Tyr, against HeLa cells was found to be 128+/-10 microM in an MTT assay, compared to 98+/-5 microM for the natural product itself. The roughly comparable cytotoxicities suggest that the cytotoxicity of callipeltin B does not arise through the formation of a quinone methide intermediate.

SUBMITTER: Krishnamoorthy R

PROVIDER: S-EPMC2013933 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature

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Synthesis and cytotoxicity of desmethoxycallipeltin B: lack of a quinone methide for the cytotoxicity of callipeltin B.

Krishnamoorthy Ravi R Richardson Brooke L BL Lipton Mark A MA

Bioorganic & medicinal chemistry letters 20070707 18

The desmethoxy analogue of the cytotoxic, cyclic depsipeptide callipeltin B was synthesized to evaluate the role of its beta-MeOTyr residue. The IC(50) of desmethoxycallipeltin B, in which the beta-MeOTyr residue was replaced by d-Tyr, against HeLa cells was found to be 128+/-10 microM in an MTT assay, compared to 98+/-5 microM for the natural product itself. The roughly comparable cytotoxicities suggest that the cytotoxicity of callipeltin B does not arise through the formation of a quinone met ...[more]

PMID: 17643303

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