title: Swarnalin and cis-swarnalin, two new tetrahydrofuran derivatives with free radical scavenging activity, from the aerial parts of Cuscuta reflexa.
abstract: The reversed-phase HPLC analysis of a methanol extract of the aerial parts of Cuscuta reflexa afforded a non-separable mixture (55 : 45) of two novel tetrahydrofuran derivatives, named swarnalin (1) and cis-swarnalin (2), and a known coumarin, 5,6,7-trimethoxycoumarin (3). The structures of the compounds were elucidated unequivocally by UV, HRFABMS and a series of 1D and 2D NMR analyses. The mixture of 1 and 2 showed significant free radical scavenging activity in the DPPH assay and the RC50 value was found to be 3.80 x 10(-4) mg mL(-1) for the mixture, compared to 2.88 x 10(-5) mg mL(-1) for the positive control, quercetin.
authors.affiliation: Pharmacy Discipline, Life Science School, Khulna University, Khulna 9208, Bangladesh.
authors.forename: Shaikh J
authors.initials: SJ
authors.lastname: Uddin
authors.forename: Jamil A
authors.initials: JA
authors.lastname: Shilpi
authors.forename: Moira
authors.initials: M
authors.lastname: Middleton
authors.forename: Maureen
authors.initials: M
authors.lastname: Byres
authors.forename: Mohammad
authors.initials: M
authors.lastname: Shoeb
authors.forename: Lutfun
authors.initials: L
authors.lastname: Nahar
authors.forename: Satyajit D
authors.initials: SD
authors.lastname: Sarker
mesh_terms: D001713:Biphenyl Compounds / Q000737:chemistry; D034182:Cuscuta / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification*; D005663:Furans / Q000737:chemistry / Q000302:isolation & purification*; D006834:Hydrazines / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular; D010851:Picrates; D035261:Plant Components, Aerial / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet
chemical_list: D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D005663:Furans; D006834:Hydrazines; D010851:Picrates; C004931:1,1-diphenyl-2-picrylhydrazyl