Phytochemical investigation and biological evaluation of Dichanthium annulatum (Forrsk)

Phytochemical investigation of Dichanthium annulatum (Forrsk), herbs revealed the isolation and identification of two pairs of lignoflavone derivatives stereoisomers; an epimers of tricin 4`-O-(threo-βguaiacylglyceryl) ether (Salcolin A) and tricin 4`-O-(erythro-β-guaiacylglyceryl) ether (Salcolin B) (1) and an epimer of tricin 4`-O-[threo-β-guaiacyl-(7``-O-methyl-9``-O-acetyl)-glyceryl] ether and tricin 4`-O-[erythro-βguaiacyl-(7``-O-methyl-9``-O-acetyl)-glyceryl] ether (2), one flavone; tricin (3), two flavone glycosides; tricin 7-O-β-D-glucopyranoside (4) and tricin 7-O-neohesperidoside (5), one flavone C-glucoside; isoorientin (6), one phenolic acid; p-coumaric acid (7), one lignan; 4-ketopinoresinol (8) and two sterols; stigmasterol (9) and β-sitosterol-3-O-β-D-glucoside (10). The structural elucidations of isolated compounds were established on the basis of NMR and MS spectral analyses. All isolated compounds and biological activities for different extracts, n-hexane, ethyl acetate and n-butanol fractions (antiviral, antimicrobial and cytotoxic activities) of Dichanthium annulatum were done for the first time.