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Total Synthesis of (±)-Allocolchicine and Its Analogues Using Co-Catalyzed Alkyne [2 + 2 + 2]-Cyclotrimerization.

ABSTRACT: The total synthesis of (±)-allocolchicine has been completed by employing cobalt-catalyzed alkyne [2 + 2 + 2]-cyclotrimerization as the key reaction. The essential diyne has been synthesized from easily available 3,4,5-trimethoxybenzaldehyde following simple chemical transformations. In general, the cycloaddition gave a mixture of C(9) and C(10) isomers thus allowing the synthesis of both allocolchicine and its C(10)-carboxylate. Because this cycloaddition was employed at the penultimate stage, it allowed the synthesis of various analogues having the diverse functionality at C(9) and/or C(10) of ring C.

SUBMITTER: Paymode DJ

PROVIDER: S-EPMC6644368 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Total Synthesis of (±)-Allocolchicine and Its Analogues Using Co-Catalyzed Alkyne [2 + 2 + 2]-Cyclotrimerization.

Paymode Dinesh J DJ Ramana Chepuri V CV

ACS omega 20170908 9

The total synthesis of (±)-allocolchicine has been completed by employing cobalt-catalyzed alkyne [2 + 2 + 2]-cyclotrimerization as the key reaction. The essential diyne has been synthesized from easily available 3,4,5-trimethoxybenzaldehyde following simple chemical transformations. In general, the cycloaddition gave a mixture of C(9) and C(10) isomers thus allowing the synthesis of both allocolchicine and its C(10)-carboxylate. Because this cycloaddition was employed at the penultimate stage, ...[more]

PMID: 31457824

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