Analisis hubungan kuntitatif struktur-aktivitas (HKSA) dari senyawa aktif antimalaria diterpen kassan hasil isolasi dari biji Bagore (Caesalpinia crista Linn) dengan parameter elektronik

Abstract

Quantitative Structure-Activity Relationship (QSAR) study have been conducted to antimalarial active compounds of cassane-type diterpenes isolated from seed kernels of Bagore (Caesalpinia crista Linn.), using the atomic net charges data resulted from AM1 method of semi-empirical calculations. The aim of this research is to determine the mathematic equation model of quantitative structure-activity relationship from antimalarial active compounds of cassane-type diterpenes isolated from seed kernels of Bagore (Caesalpinia crista Linn.) using the electronic parameter of AM1 method. The best QSAR equation model was determined by multiple linier regression analysis and tested by leave-one out type of cross validation methods. The result indicates that the biological activity is represented by a linier function of activity versus atomic net charges of C1, C2, C3, C4, and C6 which is expressed by : Log (1/C) = -7,362(+ 4,251) qC1 +3,258 (+ 4,590) qC2 + 11,038 (+4,485) qC3 + 29,421 (+20,542) qC4 + 19,849 (+6,171) qC6 + 8,541 (+2,256). The equation is significant at 95% level. The cross validation analysis give minimal value of PRESS=64,372 and SEP = 2,93; where Log (1/IC50) = biological activity and q = atomic net charges