Elucidación Estructural Por RMN de Una y Dos Dimensiones Del Esqueleto De Briarellina.

O. Cobar

doi:10.54495/Rev.Cientifica.EdicionEspecial2008.183

Authors

O. Cobar Departamento de Química Orgánica, Facultad de Ciencias Químicas y Farmacia, Laboratorio de Investigación en Productos Naturales -LIPRONAT-

DOI:

https://doi.org/10.54495/Rev.Cientifica.EdicionEspecial2008.183

Keywords:

Gorgonian octocorals, Briareum, secondary metabolites, nuclear magnetic resonance, diterpenes, briarellins, asbestinins, 2D-NMR, sub-spin system

Abstract

Caribbean gorgonian corals of the genus Briareum (Cnidaria, Gorgonaceae), have proven to be an important source of bioactive secondary metabolites. The gorgonian produces mainly three type of diterpenes: asbestinins,

Caribbean gorgonians of the genus Briareum (Cnidaria, Gorgonaceae), are an important source of bioactive secondary metabolites.

They biosynthesize three basic types of diterpenes; asbestinines, briarellinas and briareinas. Briarellins A-R and briarellins D and K peroxides are the only metabolites that have the briarelline skeleton that have been isolated from a marine organism in the Caribbean region.

These highly functionalized diterpenes are part of the family of 2,11 cyclized Cembranoids, whose biosynthetic origin is proposed to derive from the cembrane carbon skeleton, via various oxidative cyclizations and methyl rearrangements.

In this work, the Nuclear Magnetic Resonance NMR-properties of the carbon skeleton of Briarellina and the comparison between the two types of existing briarellinas, and of these, with that of asbestinines, are widely discussed.

Through the concerted and exhaustive application of one- and two-dimensional NMR techniques, its four spin sub-systems and the connectivity between them to structure the carbon skeleton of the Briarellinas are shown.

By comparing the 'H-NMR and 13C-NMR spectra between asbestinines and the different types of briarellins, clear differences are documented that allow differentiating between these types of secondary metabolites and even the stereochemistry on certain quinal centers around the carbon skeleton. of these compounds.

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