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Coibacins A and B: total synthesis and stereochemical revision.

ABSTRACT: The interface between synthetic organic chemistry and natural products was explored in order to unravel the structure of coibacin A, a metabolite isolated from the marine cyanobacterium cf. Oscillatoria sp. that exhibits selective antileishmanial activity and potent anti-inflammatory properties. Our synthetic plan focused on a convergent strategy that allows rapid access to the desired target by coupling of three key fragments involving E-selective Wittig and modified Julia olefinations. CD measurements and comparative HPLC analyses of the natural product and four synthetic stereoisomers led to determination of its absolute configuration, thus correcting the original assignment at C-5 and unambiguously establishing those at C-16 and C-18. Additionally, we synthesized coibacin B on the basis of the assignment of configuration for coibacin A.

SUBMITTER: Carneiro VM

PROVIDER: S-EPMC3962765 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

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Coibacins A and B: total synthesis and stereochemical revision.

Carneiro Vânia M T VM Avila Carolina M CM Balunas Marcy J MJ Gerwick William H WH Pilli Ronaldo A RA

The Journal of organic chemistry 20140109 2

The interface between synthetic organic chemistry and natural products was explored in order to unravel the structure of coibacin A, a metabolite isolated from the marine cyanobacterium cf. Oscillatoria sp. that exhibits selective antileishmanial activity and potent anti-inflammatory properties. Our synthetic plan focused on a convergent strategy that allows rapid access to the desired target by coupling of three key fragments involving E-selective Wittig and modified Julia olefinations. CD meas ...[more]

PMID: 24359482

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