Isolation of 2, 5-dithia-3, 6-diazabicyclo [2.2.1] heptane and GC-MS analysis of silylated extract from <i>Tragia benthamii</i>

Abstract

Tragia benthamii is a medicinal plant of repute endemic in West Africa. However, despite the traditional uses of the plant its secondary metabolites are yet to be profiled. Thus, this study aimed at identifying the chemical  constituents of T. benthamii. Air-dried samples (600 g) of the plant were extracted with aqueous ethanol (95 %) and thereafter, portions of the crude extract obtained were used separately for chromatographic  purifications, GC-MS analysis and spectrophotometric quantitation of the secondary metabolites. The chromatographic purification of the extract afforded a pure compound elucidated as 2,5-dithia-3,6-diazabicyclo [2.2.1] heptane using spectroscopic techniques. Upon silylation and GC-MS analysis of the extract, derivatives of sugar (34.65%), fatty acids (24.11%) and phytol (21.00%) were identified as principal constituents. Also, a total of 6.25 mg rutin/g, 5.18 mg ginsenoside/g and 6.84 mg glucose/g dry weight sample were obtained for flavonoids, saponins and carbohydrate, respectively from the spectrophotometric quantitation. These secondary metabolites are being reported for the first time from this plant.

Keywords: Tragia benthamii; secondary metabolites; quantitative analysis; silylation