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Synthetic Studies Towards the Core Structure of Nakadomarin A by a Thioamide-Based Strategy.

ABSTRACT: The tricyclic BCD substructure of the marine natural product nakadomarin A has been synthesised. The strategy utilised a key carbon-carbon bond-forming reaction between a furan and an N-acyliminium ion derived from a secondary thiolactam. In addition, a novel three-component coupling reaction between a thioamide, an allylic bromide and an isocyanate, leading to the establishment of two new stereogenic centres, is reported. Two key steps in a projected total synthesis of nakadomarin A have been realised by using the unique chemistry of thioamides. Formation of the carbocyclic B ring can be effected by nucleophilic attack of a furan on a thiolactam-derived iminium ion, and the key quaternary centre can be established by a novel three-component coupling reaction.

SUBMITTER: Chavda JK

PROVIDER: S-EPMC4015372 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

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Synthetic Studies Towards the Core Structure of Nakadomarin A by a Thioamide-Based Strategy.

Chavda Jai K JK Procopiou Panayiotis A PA Horton Peter N PN Coles Simon J SJ Porter Michael J MJ

European journal of organic chemistry 20131114 1

The tricyclic BCD substructure of the marine natural product nakadomarin A has been synthesised. The strategy utilised a key carbon-carbon bond-forming reaction between a furan and an <i>N</i>-acyliminium ion derived from a secondary thiolactam. In addition, a novel three-component coupling reaction between a thioamide, an allylic bromide and an isocyanate, leading to the establishment of two new stereogenic centres, is reported. Two key steps in a projected total synthesis of nakadomarin A have ...[more]

PMID: 24829538

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