ABSTRACT
Two pairs of flavonoid enantiomers (1a/1b and 2a/2b) together with three known analogues (3-5) were isolated from the heartwood of Dalbergia odorifera T. Chen. Their structures were elucidated by extensive spectroscopic analysis (1 D and 2 D NMR, UV, IR, and HRMS) and experimental and calculated ECD data. Compound 2 features an unusual 2-methyl-3(2H)-furanone moiety forming the C-ring of flavonoid, and its putative biosynthetic pathway is also proposed. Compounds 3â5 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 values of 14.7 ± 0.3 µM, 40.2 ± 1.1 µM, and 3.2 ± 0.1 µM, respectively.
Subject(s)
Dalbergia , Flavonoids , Mice , Animals , Flavonoids/pharmacology , Flavonoids/chemistry , Dalbergia/chemistry , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemistry , Plant Extracts/chemistry , RAW 264.7 CellsABSTRACT
This study aims to study the chemical components from the gum resin of Boswellia carterii. Five cembranoid diterpenes were isolated from the gum resin of B. carterii by various of column chromatographies including silica gel, Sephadex LH-20, and semi-preparative HPLC. Their structures were identified on the basis of physicochemical properties, mass spectrometry(MS), nuclear magnetic resonance(NMR), Ultraviolet(UV) and infrared(IR) spectroscopic data. These compounds were identified as(1S,2E,4R,5S,7E,11E)-4-methoxy-5-hydroxycembrane(1),(1R~*,4R~*,5E,8E,12E,15E)-4-hydroxycembra-5,8,12,15-tetraene(2), cembrene A(3),(3S,4S,7R)-4-hydroxycembrane(4), and pavidolide D(5). Compound 1 was a new compound. Compounds 2, 4, and 5 were obtained from the gum resin of B. carterii for the first time. Compound 2 showed weak inhibition on the human liver cancer cell line HepG2.