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Selective synthesis of hydroxy analogues of valinomycin using dioxiranes.

ABSTRACT: A synthesis of representative monohydroxy derivatives of valinomycin (VLM) was achieved under mild conditions by direct hydroxylation at the side chains of the macrocyclic substrate using dioxiranes. Results demonstrate that the powerful methyl(trifluoromethyl)dioxirane 1b should be the reagent of choice to carry out these key transformations. Thus, a mixture of compounds derived from the direct dioxirane attack at the ?-(CH(3))(2)C-H alkyl chain of one Hyi residue (compound 3a) or of one Val moiety (compounds 3b and 3c) could be obtained. Following convenient mixture separation, each of the new oxyfunctionalized macrocycles became completely characterized.

SUBMITTER: Annese C

PROVIDER: S-EPMC3205966 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Selective synthesis of hydroxy analogues of valinomycin using dioxiranes.

Annese Cosimo C Fanizza Immacolata I Calvano Cosima D CD D'Accolti Lucia L Fusco Caterina C Curci Ruggero R Williard Paul G PG

Organic letters 20110912 19

A synthesis of representative monohydroxy derivatives of valinomycin (VLM) was achieved under mild conditions by direct hydroxylation at the side chains of the macrocyclic substrate using dioxiranes. Results demonstrate that the powerful methyl(trifluoromethyl)dioxirane 1b should be the reagent of choice to carry out these key transformations. Thus, a mixture of compounds derived from the direct dioxirane attack at the β-(CH(3))(2)C-H alkyl chain of one Hyi residue (compound 3a) or of one Val mo ...[more]

PMID: 21905749

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