The physicochemical properties of 4-hydroxy-7-methoxy-3-phenyl-2H-chromen-2-one (4HC) and β-cyclodextrins (CDs) inclusion complexes were investigated. The phase solubility profile of 4HC with β-cyclodextrin derivatives was classified as AL-type. Stability constants for complexes with 1:1 molar ratios were calculated from the phase solubility diagrams and indicate the following trend: DMβCD>HPβCD>βCD. The highest value of the binding constant was for 4HC-DMβCD; the binding association constant (K a) for this complex was determined at different temperatures and the thermodynamic data indicate that 4HC-DMβCD association is mainly an entropically driven process. 1H NMR and ROESY were carried out, revealing that 4HC is embedded in the apolar cavity of DMβCD with the 4OH group buried in the cyclodextrin cavity with the phenyl group outside, near the primary rim. These results are in agreement with ORACFL values; the decrease in the antioxidant activity of 4HC-DMβCD is explained by the effective protection of the hydroxyl group due to complexation.
研究了
4-羟基-
7-甲氧基-3-苯基-2H-色烯-2-酮(4HC)与 β-
环糊精(CDs)包合复合物的理化性质。4HC 与 β-
环糊精衍
生物的相溶性曲线被归类为 AL 型。根据相溶解度图计算出了摩尔比为 1:1 的复合物的稳定常数,并显示出以下趋势:
DMβCD>HPβCD>βCD。4HC-
DMβCD的结合常数值最高;在不同温度下测定了该复合物的结合关联常数(K a),热力学数据表明,4HC-
DMβCD的结合主要是一个熵驱动过程。进行的 1H NMR 和 ROESY 分析表明,4HC 嵌入
DMβCD 的极性空腔中,4OH 基团埋在
环糊精空腔中,苯基在外面,靠近主边缘。这些结果与 ORACFL 值相吻合;4HC-
DMβCD 抗氧化活性降低的原因是络合作用有效保护了羟基。