Iridoid glucosides from the stems of three bioactive Brazilian Faramea species (Rubiaceae)

Abstract In this paper our previous chemical study of the anti-dengue active species Faramea bahiensis, Faramea hyacinthina and Faramea truncata (synonym of Faramea caudata ) (Rubiaceae) is complemented by isolating from their stems, through a combination of silica gel and Sephadex LH-20 column chromatography and reversed-phase solid-phase extraction, the known iridoid glucosides monotropein ( 1 ), monotropein methyl ester ( 2 ) and 10-deacetylasperulosidic acid ( 3 ). The structures were established by HPLC-DAD-MS/MS analysis, NMR spectroscopy and comparison with literature data. This is the first report on the occurrence of these compounds in the genus Faramea Aubl. This work contributes to expand the knowledge of the chemical diversity of this botanical genus, of which a limited number of identified compounds have been reported.