PREPARATION OF STILBENE OLIGOMER BY OXIDATIVE COUPLING REACTION

AIM　Study the oxidative coupling reaction of isorhapontigenin using FeCl3 as oxidant in order to obtain multiple isorhapontigenin oligomer for pharmacological tests. METHODS　The products were isolated by silica gel chromatography, flash chromatography ODS Rp-18 and semipreparative HPLC. The structures of three major products have been established by spectroscopic evidence (IR, UV, EI-MS, FAB-MS, ¹HNMR, ¹³CNMR, ¹³C-¹H　COSY, HMBC spectrum). RESULTS　Shegansu B(4), bisisorhapontigenin A(2) and B(3) were obtained as major products and determined as isorhapontigenin dimers which resulted from β-6，β-4 and β-5′ coupling, respectively.CONCLUSION　Bisisorhapontigenin A and B were new compounds. Pharmacological tests showed that shegansu B and bisisorhapontigenin A had inhibitiory effect on leukotriene B4 and antogonistic action on leukotriene D4 receptor respectively. Bisisorhapontigenin B showed inhibitiory effect of TNF-α.