Crystal Structure, Stability and Dissolution of a Drug-drug Molecular Salt Hydrate of Berberine with Protocatechuic Acid

摘要

A drug-drug molecular salt hydrate of berberine and protocatechuic acid has been prepared.Protocatechuic acid lost its carboxylic proton and turned to be protocatechuic anion to form a 1∶1∶1 organic salt hydrate with berberine,[C20H18NO4]+[C7H5O4]-·H20 (1).Compound 1 crystallizes in the triclinic system,space group P-1 with a =7.9849(5),b =10.5437(5),c =14.3621(5) (A),a =77.983(4),β =82.900(4),γ =78.024(4)°,V=1152.82(10) (A)3,Mr =507.48,Dc =1.462 g/cm3,μ =0.929 mm-1,F(000) =532,Z =2,the final R =0.0488 and wR =0.1322 for 3993 reflections with I ＞ 2σ(Ⅰ).The hydrate exhibited good solid state stability against humidity,which may result from strong hydrogen-bonding interactions between water molecules and carboxylate groups.The hydrate also exhibited acceptable solubility and dissolution rate.