Swarnalin and cis-swarnalin, two new tetrahydrofuran derivatives with free radical scavenging activity, from the aerial parts of Cuscuta reflexa.
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.
Uddin
Shaikh J
SJ
Pharmacy Discipline, Life Science School, Khulna University, Khulna 9208, Bangladesh.
Shilpi
Jamil A
JA
Middleton
Moira
M
Byres
Maureen
M
Shoeb
Mohammad
M
Nahar
Lutfun
L
Sarker
Satyajit D
SD
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
D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D005663:Furans; D006834:Hydrazines; D010851:Picrates; C004931:1,1-diphenyl-2-picrylhydrazyl