3,4‐Disubstituted‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐2‐thiones: Synthesis, Antimicrobial Evaluation and QSAR Investigations Using Hansch Analysis

Abstract

The 3,4-disubstituted-1,2,3,4,5,6,7,8-octahydroquinazoline-2-thione derivatives were synthesized and characterized by physicochemical and spectral means, and the results of antimicrobial study of these compounds against Staphylococcus aureus, Escherichia coli, and Candida albicans by tube dilution method indicated that 4-(4-chlorophenyl)-3-(4-nitrophenylsulfonyl)-1,2,3,4,5,6,7,8-octahydroquinazoline-2-thione 6 and 4-(4-fluorophenyl)-3-(4-nitrophenylsulfonyl)-1,2,3,4,5,6,7,8-octahydroquinazoline-2-thione 12 were the most potential ones. Further, the QSAR studies by Hansch analysis applied to find out the correlation between physicochemical characteristics of synthesized compounds with antimicrobial activity demonstrated the contribution of electronic parameter, total energy (Te) and the topological parameter (valence second order molecular connectivity index (2 chi v). Excellent statistically significant models were developed by Hansch approach (r2 = 0.828-0.898) for the three microorganisms under study. The cross-validated r2 (q2), which is an indication of the predictive capability of the model for all cases was also very good (q2 = 0.776-0.875).

Lanthanum triflate triggered synthesis of tetrahydroquinazolinone derivatives of N-allyl quinolone and their biological assessment

“…4 Furthermore, quinazolinones were found to exhibit antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans. 5 Therefore, the synthesis of quinazolinone derivatives still attract much attention of modern-day medicinal chemistry research. On other hand, quinolones have maintained their pharmacological importance since their discovery based on nalidixic acid in the early 1960s.…”

Synthesis, antimicrobial evaluation, ot-QSAR and mt-QSAR studies of 2-amino benzoic acid derivatives

“…In light of above facts and in continuation of our research efforts in development of novel antimicrobial drugs (Minu et al, 2008;Narasimhan et al, 2003Narasimhan et al, , 2004Narasimhan et al, , 2006aNarasimhan et al, , b, 2007a, we hereby report the synthesis, antimicrobial evaluation and QSAR studies of a series of 2-amino benzoic acid derivatives.…”

Synthesis and QSAR evaluation of 2-(substituted phenyl)-1H-benzimidazoles and [2-(substituted phenyl)-benzimidazol-1-yl]-pyridin-3-yl-methanones

“…(5)). The topological descriptor i.e., the second order molecular connectivity index encodes information related to the degree of stargraph likeness and takes a large value for more linear molecule [32]. The trend of Eq.…”