A new catalyst with quaternary ammonium cation activated polyether chains immobilized on silica gel was applied to promote the reations of KI with n-C<sub>4</su
Twonew oleanane type saponins wereisolated from the alcoholic extract of the bark ofNothopanax davidii(Franch)Harms(Araliaceae).Their structures have been deter
A new Schiff base diol,4,4’-[3-methoxy-4-(2-hydroxy)-ethoxy]azomethine biphenyl(MHAMB),was synthesized,which was copolynerized with PEC-600 and TDI to obtain a