Evolvosides C–E, flavonol-4-O-triglycosides from Evolvulus alsinoides and their anti-stress activity

Abstract Phytochemical investigation of the n -butanol fraction of Evolvulus alsinoides (Linn.) led to the isolation of three new phenolic glycosides, evolvosides C, D and E ( 1 – 3 ) along with six known compounds ( 4 – 9 ). The structures of the compounds were elucidated on the basis of spectroscopic analysis, viz. 1D and 2D NMR experiments, chemical study, and comparison with literature data. Evolvoside C ( 1 ) was characterized as kaempferol 4′- O -β- d -glucopyranosyl-(1→2)-α- l -rhamnopyranosyl-(1→6)-β- d -glucopyranoside, whereas evolvosides D and E ( 2 – 3 ) were found to be mono and di- O -methyl derivatives of 1 . The new compounds ( 1–3 ) represent rare triglycoside derivatives of flavonol at C-4′. The isolated compounds ( 1 – 6 ) were screened for acute stress-induced biochemical changes in male Sprague–Dawley rats at a dose of 40 mg/kg body weight. Compounds 1 and 2 displayed anti-stress effects by normalizing hyperglycemia, plasma corticosterone, plasma creatine kinase, and adrenal hypertrophy. Compounds 3 and 6 were also found to be effective in normalizing most of these stress parameters, whereas compounds 4 and 5 were ineffective in normalizing most of these effects.