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Twenty one chalcone derivatives were synthesized using Claisen-Schmidt condensation, their antimalarial activity against Plasmodium falciparum was determined and quantitative structure–activity relationship (QSAR) was developed. Condensation of substituted acetophenones with various aromatic aldehydes at room temperature gave chalcones in 75–96% yield. Chalcones are secondary metabolites of terrestrial plants, precursors for the biosynthesis of flavonoids and exhibit various biological activities. Antiplasmodial IC50 (half-maximal inhibitory concentration) activity of a compound against malaria parasites in vitro provides a good first screen for identifying the antimalarial potential of the compound. The most active compound was Trans-3-(1H-indol-3-yl)-1-(2'-hydroxyphenyl)-2-propen-1-one(1b) with IC50 of 2.1 µM/L. Molecular mechanism was explored through in silico docking & ADMET studies for the active compounds. [ABSTRACT FROM AUTHOR]

In our prior studies, we reported some known antitubercular drugs (rifampicin and streptomycin) and newly synthesized chalcone derivatives (16-26) tested in vitro against Mycobacterium tuberculosis H37Rv strain. Most of the tested compounds were efficient antimycobacterial agents showing minimum inhibitory concentration values ranging from 3.5 to 30 µg mL−1. In the present work, a quantitative structure-activity relationship (QSAR) study has been performed on these active chalcone derivatives to correlate their chemical structures with their observed inhibiting activity against M. tuberculosis. A QSAR model that is able to correlate well the antitubercular activity with the chemical structures of active chalcone derivatives 16, 24, 25a, 25c, and 26 has been developed, which is potentially helpful in the design of novel and more potent antitubercular agents. The r2 and rCV2 of a newly derived QSAR model were 0.89 and 0.84, respectively. The QSAR study indicates that chemical properties, viz. heat of formation (kcal mol−1), lowest unoccupied molecular orbital energy (eV), and amine, hydroxyl, and methyl groups counts, correlate well with the activity. In silico screening results for oral bioavailability and absorption, distribution, metabolism, excretion, and toxicity compliance showed that compounds 25a, 25c, and 24 were found active similar to rifampicin and streptomycin. The docking study for the exploration of mechanism of action showed high binding affinity of active derivatives. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In the present work, quantitative structure-activity relationship (QSAR) models of camptothecin derivatives against DNA Topoisomerase-I (DNA Topo-I) were developed by multiple linear regression method using leave-one-out validation approach. The r2 and rCV2 of the model were 0.89 and 0.86, respectively. The QSAR study indicates that chemical descriptors, namely Connectivity Index (order 1, standard), Electron Affinity (eV), Molecular Weight, Group Count (ether) are correlated well with activity. Further, screening for drug likeness, ADME and toxicity showed that compound CPT9, CPT14, CPT20, CPT21 and CPT22 exhibits marked anticancer activity and possesses two times more potent than standard drug camptothecin. The docking study showed a high binding affinity of predicted active derivatives and showed H-bond formation with GLY363, ARG364, LYS374, GLN421, ARG488, and ASP-533 residues, therefore considered as more stable and potent anticancer compounds. The obtained results can be used for the design of novel potent and selective inhibitors of DNA Topo-I. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Two triterpenoids ursolic acid (1) and lupeol (2) isolated and characterized from Eucalyptus tereticornis and Gentiana kurroo were subjected to in silico QSAR modeling and docking studies and later the predicted results were confirmed through in vivo experiments. QSAR modeling results showed that both the triterpenoids possess immunomodulatory and anti-inflammatory activity comparable to boswellic and cichoric acids, but were less active than levamisol. Docking results suggested that both the triterpenoids (1 and 2) showed immune modulatory and anti-inflammatory activity due to high binding affinity to human receptors viz., NF-kappaB p52 (−50.549kcal/mol), tumor necrosis factor (TNF-alpha) (−47.632kcal/mol), nuclear factor NF-Kappa-B P50 (−16.798kcal/mol) and cyclooxygenase-2 (−55.244kcal/mol). Further both the triterpenoids (1 and 2) were subjected to in vivo immunomodulatory activity in female Swiss albino mice. The experimental mice were divided into nine groups, each comprised of six mice. These received oral treatment for a period of 28days. The triterpenoids (1 and 2) showed significant increased in humoral immune function, but no significant changes were observed in cell mediated immune response and hematological parameters. The in silico and in vivo experimental data suggested that both the triterpenoids 1 and 2 may be considered as potential immunomodulatory drug-like molecules. [Copyright &y& Elsevier]

Natural coumarinolignoids isolated from the seeds of Cleome viscosa consist of a racemic mixture of cleomiscosins A, B and C. To screen out potential lead, anti-inflammatory activity of the isolated compounds was evaluated through molecular docking and QSAR studies by using reported in vivo activity of Swiss albino mice. Based on docking binding affinity, a possible mechanism of action has been hypothesized which constitute toll-like receptors (TLR-4), cluster of differentiation molecules (CDs), iNOS, COX-2 and STAT-6 proteins. It was very interesting to find that the 3D topology of the active site of COX-2 from the docking was in good agreement with QSAR model and in silico ADME/T parameters. A forward feed multiple linear regression model was developed with r2 = 0.92 and rCV2 = 0.87. This study showed that chemical descriptors, for example dipole vector- X, dipole vector- Y, steric energy, LUMO energy, size of smallest ring, size of largest ring and carboxyl group count, correlate reasonably well with experimental in vivo activity (logLD50). QSAR study indicates that dipole vector- Y and carboxyl group count have negative correlation with activity. Cleomiscosins also showed compliance with 95% of in silico ADME/T properties of available drugs, e.g. serum protein binding, blood-brain barrier, CNS activity, HERG K+ channel activity, apparent Caco-2 permeability, apparent MDCK permeability, skin permeability and human oral absorption in GI. Besides, toxicity screening study suggests that cleomiscosin molecules possess no toxicity risk parameters. This study offer useful references for understanding and molecular design of inhibitors with improved anti-inflammatory activity. [ABSTRACT FROM AUTHOR]

Abstract: A series of five (6a–8b) novel polyhalogenated derivatives and an interesting ester (9a) derivative have been synthesized from cleomiscosin A methyl ether. All the six derivatives were subjected to in silico QSAR modeling and docking studies and later the predicted results were confirmed through in vitro experiments. QSAR modeling results showed that compounds 6a and 9a possessed anti-inflammatory activity comparable or even higher than diclofenac sodium. Docking results revealed that compounds 9a and 6a showed very good anti-inflammatory activity due to low docking energies of viz., IL6 (−92.45 and −81.993kcalmol−1), TNF-α (−94.992 and −69.235kcalmol−1) and IL1β (−67.462 and −65.985kcalmol−1). Further all the six novel derivatives were subjected for in vitro anti-inflammatory activity using primary macrophages cell culture bioassay system. At the initial doses of 1μg/ml and 10μg/ml, the pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) were quantified from cell culture supernatant using enzyme linked immunosorbent assay (ELISA). The in vitro effect of 6a–9a on cell viability in mouse peritoneal macrophage cells isolated from mice was evaluated using MTT assay. The in silico and in vitro data suggested that all the derivatives might be considered as potential anti-inflammatory drug-like molecules. [Copyright &y& Elsevier]