邻苯二甲酸酯类化合物生物降解的电性拓扑研究

计算了9种邻苯二甲酸酯的两类拓扑指数值:(1)基于原子类型特征的电性拓扑状态指数(En);(2)自分子拓扑图的邻接矩阵衍生的分子连接性指数(mXtv).这些拓扑指数被用于关联9种邻苯二甲酸酯的生物降解速率常数(Kb)及其半衰期(lnt1/2),经向后逐步回归与偏最小二乘法,建立了定量结构-生物降解相关(QSBR)模型,其四元最佳方程的相关系数(R2)依次为0.995、0.986.这两个方程的平均估算误差接近实验误差,并通过Jackkn ife的逐一剔除法证明有良好的可靠性与稳定性.结果表明,这些模型能够较好地解释邻苯二甲酸酯的生物降解性的递变规律.

Investigation into the biodegradability of phthalic acid ester compounds with molecular connectivity indices and electrotopological states indices

Two topological indices of nine kinds of phthalic acid esters were calculated.One of the topological indices,the electrotopological indices(E_n), is based on atomic characters.Another one is molecular connectivity indices((~(m)X~v_t)),which was derived from adjacent matrix based on molecular topological map.These topological indices were related with the biodegradation rate(K_b) and half-life(lnt_(1/2)) of nine kinds of phthalic acid esters respectively.Their quantitative structure-biodegradation relationship model(QSBR) was designed by using backwards stepwise regression and partial least square(PLS).The coefficients of 4-factor best equations(R~2) are 0.995 and 0.986,respectively.The average values of estimated standard error is small so the calculated values are close to the corresponding experimental ones.It shows good reliability and robustness by using Jackknife's leave-one-out method.The results show that these models can be used to explain the regulation rule of phthalic acid esters' biodegradation.