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The enantiospecific synthesis of (+)-monomorine I using a 5-endo-trig cyclisation strategy.

ABSTRACT: We have developed a general strategy for the synthesis of 2,5-syn disubstituted pyrrolidines that is based on the multi-faceted reactivity of the sulfone moiety and a 5-endo-trig cyclisation. This methodology was applied to the synthesis of indolizidine alkaloid monomorine I. Two factors were key to the success of this endeavour; the first was the choice of nitrogen protecting group whilst the second was the conditions for the final stereoselective amination step. Employing a combination of different protecting groups and an intramolecular reductive amination reaction we were able to prepare (+)-monomorine I in just 11 steps from commercially available D-norleucine in a completely stereoselective manner.

SUBMITTER: Berry MB

PROVIDER: S-EPMC2151076 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature

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The enantiospecific synthesis of (+)-monomorine I using a 5-endo-trig cyclisation strategy.

Berry Malcolm B MB Craig Donald D Jones Philip S PS Rowlands Gareth J GJ

Beilstein journal of organic chemistry 20071108

We have developed a general strategy for the synthesis of 2,5-syn disubstituted pyrrolidines that is based on the multi-faceted reactivity of the sulfone moiety and a 5-endo-trig cyclisation. This methodology was applied to the synthesis of indolizidine alkaloid monomorine I. Two factors were key to the success of this endeavour; the first was the choice of nitrogen protecting group whilst the second was the conditions for the final stereoselective amination step. Employing a combination of diff ...[more]

PMID: 17996034

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