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De novo asymmetric synthesis of fridamycin E.

ABSTRACT: A de novo asymmetric synthesis of (R)- and (S)-fridamycin E has been achieved. The entirely linear route required only nine steps from commercially available starting materials (16% overall yield). Key transformations included a Claisen rearrangement, a Sharpless dihydroxylation and a cobalt-catalyzed epoxide carbonylation to give a ?-lactone intermediate. Antibacterial activities were determined for both enantiomers using two strains of E. coli, with the natural (R)-enantiomer showing significant inhibition against a Gram-(+)-like imp strain (MIC = 8 ?M).

SUBMITTER: Chen Q

PROVIDER: S-EPMC3476477 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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De novo asymmetric synthesis of fridamycin E.

Chen Qian Q Mulzer Michael M Shi Pei P Beuning Penny J PJ Coates Geoffrey W GW O'Doherty George A GA

Organic letters 20111122 24

A de novo asymmetric synthesis of (R)- and (S)-fridamycin E has been achieved. The entirely linear route required only nine steps from commercially available starting materials (16% overall yield). Key transformations included a Claisen rearrangement, a Sharpless dihydroxylation and a cobalt-catalyzed epoxide carbonylation to give a β-lactone intermediate. Antibacterial activities were determined for both enantiomers using two strains of E. coli, with the natural (R)-enantiomer showing significa ...[more]

PMID: 22107019

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