Rougier Natalia M, Cruickshank Dyanne L, Vico Raquel V, Bourne Susan A, Caira Mino R, Buján Elba I, de Rossi Rita H
Instituto de Investigaciones en Físico Química de Córdoba (INFIQC), Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina.
Carbohydr Res. 2011 Feb 1;346(2):322-7. doi: 10.1016/j.carres.2010.06.016. Epub 2010 Dec 10.
The hydrolysis reaction of fenitrothion was studied in water containing 2% dioxane and in the presence of native cyclodextrins (α-, β- and γ-CD) and two commercially available modified derivatives, namely, permethylated β- and α-cyclodextrin (TRIMEB and TRIMEA, respectively). The kinetics of the reaction in the presence of TRIMEA could not be measured because the complex formed is insoluble and precipitated even at low concentration. On the other hand, the reaction is only weakly affected by the presence of α-CD. The hydrolysis reaction is inhibited by all the other cyclodextrins. From the kinetic data the association equilibrium constants for the formation of the 1:1 inclusion complexes were determined as 417, 511 and 99M(-1) for β-CD, TRIMEB and γ-CD, respectively. Despite the differences in the association constants for β- and γ-CD, the observed inhibition effect is about the same and this is due to the fact that the rate of hydrolysis in the cavity of γ-CD is smaller than that in the cavity of β-CD. The strongest inhibitor is TRIMEB and this result is consistent with the known structure of the complex in the solid state.
在含有2%二氧六环的水中以及天然环糊精（α-、β-和γ-环糊精）和两种市售改性衍生物即全甲基化β-环糊精和α-环糊精（分别为TRIMEB和TRIMEA）存在的条件下，研究了杀螟硫磷的水解反应。由于形成的络合物不溶，即使在低浓度下也会沉淀，因此无法测定TRIMEA存在时反应的动力学。另一方面，α-环糊精的存在对反应的影响很小。所有其他环糊精均抑制水解反应。根据动力学数据，β-环糊精、TRIMEB和γ-环糊精形成1:1包合物的缔合平衡常数分别确定为417、511和99M⁻¹。尽管β-环糊精和γ-环糊精的缔合常数存在差异，但观察到的抑制效果大致相同，这是因为γ-环糊精腔内的水解速率小于β-环糊精腔内的水解速率。最强的抑制剂是TRIMEB，这一结果与固态络合物的已知结构一致。
