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Studies toward the total synthesis of dihydrolycolucine. Preparation of AB and CEF ring fragments.

ABSTRACT: A strategy for the synthesis of the lycopodium alkaloid dihydrolycolucine (1) has been investigated. Synthetic routes were developed based on N-acylpyridinium salt chemistry to prepare target fragments 3 and 4 that could ultimately converge to the natural product. Key reactions include IMDA cycloadditions and retro-Mannich ring-openings to form both the AB and the EF ring fragments. The ring C precursor was prepared using pyridine substitution and directed lithiation chemistry. A Suzuki cross-coupling of rings C and EF led to the CEF ring fragment. Initial attempts at closure of the seven-membered D ring were unsuccessful.

SUBMITTER: Cash BM

PROVIDER: S-EPMC4066915 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

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Studies toward the total synthesis of dihydrolycolucine. Preparation of AB and CEF ring fragments.

Cash Brandon M BM Prevost Natacha N Wagner Florence F FF Comins Daniel L DL

The Journal of organic chemistry 20140529 12

A strategy for the synthesis of the lycopodium alkaloid dihydrolycolucine (1) has been investigated. Synthetic routes were developed based on N-acylpyridinium salt chemistry to prepare target fragments 3 and 4 that could ultimately converge to the natural product. Key reactions include IMDA cycloadditions and retro-Mannich ring-openings to form both the AB and the EF ring fragments. The ring C precursor was prepared using pyridine substitution and directed lithiation chemistry. A Suzuki cross-co ...[more]

PMID: 24841361

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