|Planta Medica, 2011 , 77 (12):42. |
|New biphenyl derivatives and anti-inflammatory constituents from the stem bark of Magnolia officinalis[Reference: WebLink]|
|The stem bark of Magnolia officinalis Rehd. et Wils. (Magnoliaceae) has been used as a traditional medicine for the treatment of gastrointestinal disorders, bronchitis, and emphysema, in China, Taiwan, Japan, and Korea . Chemical studies have revealed a variety of neo-lignans and alkaloids as constituents of this plant. Many of these compounds exhibit central depressant effect, muscle relaxation, and antigastric ulcer, antibacterial, antiallergic, vasorelaxant, and neurotrophic activities.
METHODS AND RESULTS:
Investigation on EtOAc-soluble fraction of the stem bark of M. officinalis has led to the isolation of three new biphenyls, 5-allyl-5'-(1-hydroxyallyloxy)biphenyl-2,2-diol (1), 5,5'-diallyl-2'-(allyloxy)biphenyl-2-ol (2), and 5,5'-diallyl-2'-(3-methylbut-2-enyloxy)biphenyl-2-ol (3), together with 12 known compounds, including four neolignans, magnolol (4), honokiol (5), (-)-monoterpenylmagnolol (6), and randainal (7), two norlignans, magnaldehyde D (8) and Randaiol (9), and six steroids, β-sitostenone (10), stigmasta-4,22-dien-3-one (11), β-sitosterol (12), stigmasterol (13), 3β-hydroxystigmast-5-en-7-one (14), and 3β-hydroxystigmasta-5,22-dien-7-one (15). The structure of new compounds (1-3) were determined through spectroscopic and MS analyses. Among the isolates, magnolol (4) and honokiol (5) exhibited potent inhibition against fMLP-induced superoxide production with IC50 values of 4.42±0.24 and 0.68±0.20μg/mL, respectively. In addition, magnolol (4) inhibited fMLP/CB-induced elastase release with an IC50 values of 1.45±0.20μg/mL.