title: New acyclic secondary metabolites from the biologically active fraction ofAlbizia lebbeckflowers.
abstract: The total extract ofAlbizia lebbeckflowers was examinedin vivofor its possible hepatoprotective activity in comparison with the standard drug silymarin at two doses. The higher dose expressed promising activity especially in reducing the levels of AST, ALT and bilirubin. Fractionation via liquid-liquid partition and reexamination of the fractions revealed that then-butanol fraction was the best in improving liver biochemical parameters followed by then-hexane fraction. However, serum lipid parameters were best improved with CHCl3fraction. The promising biological activity results initiated an intensive chromatographic purification ofA. lebbeckflowers fractions. Two compounds were identified from natural source for the first time, the acyclic farnesyl sesquiterpene glycoside1-O-[6-O-α-l-arabinopyranosyl-β-d-glucopyranoside]-(2E,6E-)-farnesol (6) and the squalene derivative 2,3-dihydroxy-2,3-dihydrosqualene (9), in addition to eight compounds reported here for the first time from the genusAlbizia; two benzyl glycosides, benzyl 1-O-β-d-glucopyranoside (1) and benzyl 6-O-α-l-arabinopyranosylβ-d-glucopyranoside (2); three acyclic monoterpene glycosides, linalylβ-d-glucopyranoside (3) and linalyl 6-O-α-l-arabinopyranosyl-β-d-glucopyranoside (4); (2E)-3,7-dimethylocta-2,6-dienoate-6-O-α-l arabinopyranosyl-β-d-glucopyranoside (5), two oligoglycosides,n-hexyl-α-l arabinopyranosyl-(1 → 6)-β-d-glucopyranoside (creoside) (7) andn-octylα-l-arabinopyranosyl-(1 → 6)-β-d-glucopyranoside (rhodiooctanoside) (8); and ethyl fructofuranoside (10). The structures of the isolated compounds were elucidated based on extensive examination of their spectroscopic 1D and 2D-NMR, MS, UV, and IR data. It is worth mentioning that, some of the isolated linalol glycoside derivatives were reported as aroma precursors.
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia.
authors.forename: Shaza M
authors.initials: SM
authors.lastname: Al-Massarani
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia; Pharmacognosy Department, Faculty of Pharmacy, Mansoura University, P.O. 35516, Mansoura, Egypt.
authors.forename: Ali A
authors.initials: AA
authors.lastname: El Gamal
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia.
authors.forename: Mohamed F
authors.initials: MF
authors.lastname: Abd El Halim
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia.
authors.forename: Mansour S
authors.initials: MS
authors.lastname: Al-Said
authors.affiliation: Pharmacognosy Department, College of Pharmacy, Sattam Bin Abdulaziz University, Al-kharj 11942, Saudi Arabia.
authors.forename: Maged S
authors.initials: MS
authors.lastname: Abdel-Kader
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia.
authors.forename: Omer A
authors.initials: OA
authors.lastname: Basudan
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia.
authors.forename: Saleh I
authors.initials: SI
authors.lastname: Alqasoumi
keywords: Albizia lebbeck flowers; Aroma precursors; Dihydrosqualene derivatives; Farnesol derivatives; Hepatoprotective