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Synthetic Approaches to A Challenging and Unusual Structure-An Amino-Pyrrolidine Guanine Core.

ABSTRACT: The synthesis of an unreported 2-aminopyrrolidine-1-carboxamidine unit is here described for the first time. This unusual and promising structure was attained through the oxidative decarboxylation of amino acids using the pair of reagents, silver(I)/peroxydisulfate (Ag(I)/S2O82-) followed by intermolecular (in the case of l-proline derivative) and intramolecular trapping (in the case of acyl l-arginine) by N-nucleophiles. The l-proline approach has a broader scope for the synthesis of 2-aminopyrrolidine-1-carboxamidine derivatives, whereas the intramolecular cyclization afforded by the l-acylarginines, when applied, results in higher yields. The former allowed the first synthesis of cernumidine, a natural alkaloid isolated in 2011 from Solanum cernuum Vell, as its racemic form.

SUBMITTER: Rippel R

PROVIDER: S-EPMC7070370 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Synthetic Approaches to A Challenging and Unusual Structure-An Amino-Pyrrolidine Guanine Core.

Rippel Rafael R Pinheiro Luís L Lopes Mónica M Lourenço Ana A Ferreira Luísa M LM Branco Paula S PS

Molecules (Basel, Switzerland) 20200212 4

The synthesis of an unreported 2-aminopyrrolidine-1-carboxamidine unit is here described for the first time. This unusual and promising structure was attained through the oxidative decarboxylation of amino acids using the pair of reagents, silver(I)/peroxydisulfate (Ag(I)/S2O82-) followed by intermolecular (in the case of l-proline derivative) and intramolecular trapping (in the case of acyl l-arginine) by N-nucleophiles. The l-proline approach ...[more]

PMID: 32059504

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