Caffeoyl esters of threonic acid and its lactone from Viguiera Pazensis

Abstract

Dos ésteres de derivados de azúcares con ácido cafeico: 3-O-cafeoil-2-C-metil-D-treono-1,4-lactona, ácido 4-O-cafeoil-2-C-metil-D-treónico, junto con los compuestos previamente conocidos: 2-C-metil-D-treono-1,4-lactona, ácido cafeico, carabrona, 5,7,3'-trihidroxi-4'-metoxiflavona y 5,7,3'-trihidroxi-6,4'-dimetoxiflavona fueron aislados de la parte aérea de Viguiera pazensis. Las estructuras fueron determinadas utilizando una combinación de métodos espectroscópicos, incluyendo espectroscopia de RMN en una y dos dimensiones.

Two caffeoyl esters of sugar derivatives: 3-O-caffeoyl-2-C-methyl-D-threono-1,4-lactone, 4-O-caffeoyl-2-C-methyl-D-threonic acid, along with the previously known compounds: 2-C-methyl-D-threono-1,4-lactone, caffeic acid, carabrone, 5,7,3'-trihydroxy-4'-methoxyflavone, and 5,7,3'-trihydroxy-6,4'-dimethoxyflavone were isolated from the aerial parts of Viguiera pazensis. Their structures were elucidated by application of various spectroscopic methods, including 1D and 2D NMR spectroscopy.