6533b824fe1ef96bd1280992

RESEARCH PRODUCT

A Synthetic Model for the [4+2] Cycloaddition in the Biosynthesis of the Brevianamides, Paraherquamides, and Related Compounds

Juan F. Sanz-cerveraRobert M. WilliamsJ. Alberto MarcoJosé Marı&#x;a López-sánchezFlorenci V. GonzálezMarı&#x;a Eugenia Martı&#x;nezFélix Sancenón

subject

Intramolecular reactionOrganic ChemistryIntermolecular forceCyclohexeneBiochemistryCycloadditionLewis acid catalysisCatalysischemistry.chemical_compoundchemistryDrug DiscoveryOrganic chemistryCyclopenteneReactivity (chemistry)

description

Abstract The reactivity of model systems for the proposed [4+2] cycloaddition in the biosynthesis of the brevianamides, paraherquamides, and marcfortines is explored. The model for the intermolecular reaction reveals that the cycloaddition takes place under mild conditions only if activated, very reactive dienophiles are used. When relatively unreactive dienophiles such as cyclopentene and cyclohexene are used, harsh reaction conditions and/or a Lewis acid catalyst are necessary for the reaction. In contrast, the model for the intramolecular reaction demonstrates that the cycloaddition takes place within a few hours at room temperature, even in the absence of a Lewis acid catalyst. Conclusions drawn from these results are discussed in relation to the biosynthesis of the aforementioned metabolites.

https://doi.org/10.1016/s0040-4020(00)00573-1