Compounds S1 Research Articles

Synthesis of new multi-functionalized Schiff base derivatives based on vanillic acid: Antimicrobial activity, photophysical, DFT calculations and in-silico study

The paper reports the synthesis of novel multi-functional Schiff base derivatives (S1-S7) via Steglich esterification, thoroughly characterized by standard spectroscopic methods (1H NMR, 13C NMR, FT-IR and Mass spectrometry) and elemental analysis technique. Density Functional Theory calculations (including FMOs’, MEP, IR and UV–Visible), photophysical, molecular docking simulations, and in-vitro antimicrobial assays were employed to study the structure and reactivity of synthesized compounds. The study highlights significant antimicrobial activity of certain derivatives, which aligns with computational predictions. UV–Visible study identifies various transitions like π→π*, n→π* occurring in the system aligning with the theoretical absorption spectra. Biological studies reveal that compounds S1, S2 and S5 exhibit significant potency for antimicrobial investigation correlating with the computational study. Further, the calculated HOMO-LUMO band gap for S1-S7 molecules (3.29 eV) suggest their insulating nature. Notably, MEP study shows negative electrostatic potential near nitro group and the positive potential near alkyl groups indicating preferable site for electrophilic and nucleophilic attack, respectively. Moreover, molecular docking was implemented to computationally screen the multi-functionalized Schiff base along with molecular dynamics simulation including MM-PBSA energy calculation in order to discover the reasonable physiological significance ensuring stability of binding interactions of relevant molecules.

Design, one-pot synthesis, computational and biological evaluation of diaryl benzimidazole derivatives as MEK inhibitors

MEK mutations are more common in various human malignancies, such as pancreatic cancer (70–90%), mock melanoma (50%), liver cancer (20–40%), colorectal cancer (25–35%), melanoma (15–20%), non-small cell lung cancer (10–20%) and basal breast cancer (1–5%). Considering the significance of MEK mutations in diverse cancer types, the rational design of the proposed compounds relies on the structural resemblance to FDA-approved MEK inhibitors like selumetinib and binimetinib. The compound under design features distinct substitutions at the benzimidazole moiety, specifically at positions 2 and 3, akin to the FDA-approved drugs, albeit differing in positions 5 and 6. Subsequent structural refinement was guided by key elements including the DFG motif, hydrophobic pocket and catalytic loop of the MEK protein. A set of 15 diverse diaryl benzimidazole derivatives (S1–S15) were synthesized via a one-pot approach and characterized through spectroscopic techniques, including MASS, IR, 1H NMR and 13C NMR. In vitro anticancer activities of all the synthesized compounds were evaluated against four cancer cell lines, A375, HT −29, A431 and HFF, along with the standard drug trametinib. Molecular docking was performed for all synthesized compounds (S1–15), followed by 950 ns molecular dynamics simulation studies for the promising compounds S1, S5 and S15. The stability of these complexes was assessed by calculating the root-mean-square deviation, solvent accessible surface area and gyration radius relative to their parent structures. Additionally, free energy of binding calculations were performed. Based on the biological and computational results, S15 was the most potent compound and S1 and S5 are comparable to the standard drug trametinib. Communicated by Ramaswamy H. Sarma

Imidazopyridine chalcones as potent anticancer agents: Synthesis, single-crystal X-ray, docking, DFT and SAR studies.

New imidazopyridine-chalcone analogs were synthesized through the Claisen-Schmidt condensation reaction. The newly synthesized imidazopyridine-chalcones (S1-S12) were characterized using spectroscopic and elemental analysis. The structures of compounds S2 and S5 were confirmed by X-ray crystallography. The global chemical reactivity descriptor parameter was calculated using theoretically (DFT-B3LYP-3-211, G) estimated highest occupied molecular orbital and lowest unoccupied molecular orbital values and the results are discussed. Compounds S1-S12 were screened on A-549 (lung carcinoma epithelial cells) and MDA-MB-231 (M.D. Anderson-Metastatic Breast 231) cancer cell lines. Compounds S6 and S12 displayed exceptional antiproliferative activity against lung A-549 cancer cells with IC50 values of 4.22 and 6.89 µM, respectively, compared to the standard drug doxorubicin (IC50 = 3.79 μM). In the case of the MDA-MB-231 cell line, S1 and S6 exhibited exceptionally superior antiproliferative activity with IC50 of 5.22 and 6.50 μM, respectively, compared to doxorubicin (IC50 = 5.48 μM). S1 was found to be more active than doxorubicin. Compounds S1-S12 were tested for their cytotoxicity on human embryonic kidney 293 cells, which confirmed the nontoxic nature of the active compounds. Further molecular docking studies verified that compounds S1-S12 have a higher docking score and interacted well with the target protein. The most active compound S1 interacted well with the target protein carbonic anhydrase II in complex with pyrimidine-based inhibitor, and S6 with human Topo IIα ATPase/AMP-PNP. The results suggest that imidazopyridine-chalcone analogs may serve as new leads as anticancer agents.

Trifluoromethylpyridine piperazine derivatives: synthesis and anti-plant virus activity.

The cucumber mosaic virus (CMV) is well-known for its expansive host range and distribution, resulting in a detrimental effect on agricultural production, thus making it imperative to implement measures for its control. Novel compounds S1-S28 were synthesized by connecting trifluoromethyl pyridine, amide and piperazine scaffolds. Bioassays indicated that most of the synthesized compounds exhibited good curative effects against CMV, with half maximal effective concentration (EC50 ) values of compounds S1, S2, S7, S8, S10, S11, S15, and S28 being 119.6, 168.9, 197.6, 169.1, 97.9, 73.9, 224.4, and 125.2μg mL-1 , respectively, which were lower than the EC50 of ningnanmycin (314.7μg mL-1 ). Compounds S5 and S8 exhibited protective activities with EC50 of 170.8 and 95.0μg mL-1 , respectively, which were lower than ningnanmycin at 171.4μg mL-1 . The inactivation activities of S6 and S8 at 500 μg mL-1 were remarkably high at 66.1% and 78.3%, respectively, surpassing that of ningnanmycin (63.5%). Additionally, their EC50 values were more favorable at 22.2 and 18.1μg mL-1 , respectively, than ningnanmycin (38.4μg mL-1 ). And molecular docking and molecular dynamics simulation showed compound S8 had better binding with CMV-coat protein, providing a possible explanation for the anti-CMV activity of compound S8. Compound S8 showed a strong binding affinity to CMV-coat protein and impacted the self-assemble of CMV particles. Compound S8 could be a potential lead compound for discovering a new anti-plant virus candidate. © 2023 Society of Chemical Industry.

Molecular Docking and Drug-likeness Prediction of New Potent Tubulin Colchicine Binding Site Inhibitors for Potential Antitumor Drug

Cancer is a real public health problem that figures among the main causes of morbidity and mortality in the world. The Colchicine Binding Site (CBS) is an important pocket for potential tubulin polymerization destabilizers. Colchicine binding site inhibitors (CBSI) exhibit their biological effects by inhibiting tubulin assembly and suppressing microtubule formation. In order to identify new potent CBSI, molecular docking and drug likeness prediction were performed. In this context, a collection of 850 similar compounds to combretastatinA-4from PubChem database was docked into the CBS. Out of these, compounds S1 and S2 were found to have highest negative binding energy of -9.462 and -9.017 Kcal/mol respectively. Furthermore, these two compounds were predicted to have satisfying drug likeness properties, indicating that they might be promising lead compounds for further antitumor drug research.

Virtual screening and drug likeness prediction of new potent TMPRSS2 inhibitors as a potential treatment of COVID-19

Transmembrane serine protease 2 (TMPRSS2) is a human protease which plays an important role in the viral life cycle. This enzyme cleaves the spike protein required for Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) viral entry at the host cell. TMPRSS2 inhibitors might limit SARS-CoV-2 infection in the respiratory tract. This work aims at identifying new potent TMPRSS2 inhibitors for anti-SARS CoV-2 drug research. Indeed, Structure-Based Virtual Screening (SBVS) of 13 521 analog compounds to 4-carbamimidamidobenzoic acid,a potent TMPRSS2 inhibitor, was undertaken using FlexX program. Then, the top ranked 1000 compounds were re-scored using Glide Extra Precision (XP) and their binding mode into TMPRSS2 binding site was further analyzed in order to eliminate false positive ones. Finally, drug likeness and toxicity properties of the most promising inhibitors were predicted. Out of these, compounds S1 and S2 showed a higher TMPRSS2 inhibitory potency than that of GBS, the reference molecule. They also were predicted to occupy the entire TMPRSS2 binding site making a rational number of interactions. Still more remarkably, these two compounds were also predicted to have satisfying drug likeness properties, indicating that they might be promising lead compounds for further anti-SARS CoV-2 drug research.

Bioprospecting the Antibacterial Activity of Endophytic Fungi from Noni (Morinda citrifolia) against Bacterial Spot of the Passion Fruit Tree

Bacterial spot, which is the main disease occurring in passion fruit trees, is caused by the bacterium Xanthomonas axonopodis pv. passiflorae, leading to large annual losses in passion fruit crops. This study aims to find extracts and/or bioactive compounds of endophytic fungi of noni (Morinda citrifolia) to treat bacterial spot in passion fruit trees. Nine fungi isolated from a specimen of M. citrifolia from the Brazilian Amazon are studied. The fungus Guignardia mangiferae NF17 shows the best inhibition results and is selected for the isolation of its secondary metabolites by chromatography techniques. The isolated compounds Sydowinol (S1) and Sydowinin A (S2) are identified by nuclear magnetic resonance (NMR). Compounds S1 and S2, as well as the acetonitrile extract from the biomass of G. mangiferae NF17, are tested against four strains of X. axonopodis pv. passiflorae obtained from plants infected by bacterial spot, and which inhibited bacterial growth up to the lowest concentration tested (3.125 µg/mL). This study reports, for the first time, the antibacterial activity against X. axonopodis pv. passiflorae by the compounds Sydowinol and Sydowinin A. Compounds S1 and S2 are reported for the first time for the genus Gignardia.

Establishment of In Vitro and In Vivo Anticolorectal Cancer Efficacy of Lithocholic Acid-Based Imidazolium Salts.

Imidazolium salts (IMSs) are the subject of many studies showing their anticancer activities. In this research, a series of novel imidazolium salts substituted with lithocholic acid (LCA) and alkyl chains of various lengths (S1–S10) were evaluated against colon cancer cells. A significant reduction in the viability and metabolic activity was obtained in vitro for DLD-1 and HT-29 cell lines when treated with tested salts. The results showed that the activities of tested agents are directly related to the alkyl chain length, where S6–S8 compounds were the most cytotoxic against the DLD-1 line and S4–S10 against HT-29. The research performed on the xenograft model of mice demonstrated a lower tendency of tumor growth in the group receiving compound S6, compared with the group receiving 5-fluorouracil (5-FU). Obtained results indicate the activity of S6 in the induction of apoptosis and necrosis in induced colorectal cancer. LCA-based imidazolium salts may be candidates for chemotherapeutic agents against colorectal cancer.

Exploring of novel 4-hydroxy-2H-benzo[e][1,2]thiazine-3-carbohydrazide 1,1-dioxide derivative as a dual inhibitor of α-glucosidase and α-amylase: Molecular docking, biochemical, enzyme kinetic and in-vivo mouse model study

Diabetes mellitus (DM) is a metabolic disorder that leads to hyperglycemia due to improper insulin secretion. The study aims to investigate the anti-diabetic potential of benzothiazine derivatives. Molecular docking and Molecular Dynamics simulation study revealed that Compound S6 (4-hydroxy-2H-benzo[e][1,2]thiazine-3-carbohydrazide 1,1-dioxide) and S7 (4-Hydroxy-2-methyl-2H-1,2-benzothiazine-3-carbohydrazide 1,1-dioxide) had less conformational changes during MD simulation analysis at 100 ns. Compound S6 and S7 showed potent activity with IC50 values of 5.93 μM, 6.91 μM and 75.17, 29.10 μM for α-glucosidase and α-amylase respectively and competitive type of inhibition was observed during enzyme kinetic study with a low value of Ki and Ki′ for α-glucosidase and α-amylase, respectively. S6 has the lowest Ki (0.0736) and Ki′ (−0.0982) for α-glucosidase. Furthermore, in vivo studies were carried out to distinguish the effects of the drug on the body. Histology analysis on mice model showed that compound S6 has a low necrosis rate in the liver, kidney, and pancreas compared to S7. Biochemical results of S6 revealed lower sugar level (112 mg/dL), increase insulin secretion (23, 25 μM/L), and low level of cholesterol (80, 85 mg/dL) and creatinine (1.6, 1.4 mg/dL). The results conclude that compound S6 is a new anti-diabetic agent that minimizes hyperglycemia complications.

Virtual Screening Based Discovery of PTP1B Inhibitors and Their Biological Evaluations

Background : The discovery of novel antidiabetics for the treatment of type 2 diabetes mellitus (T2DM) is an important task nowadays because the current treatment approaches have certain limitations. The reported studies showed that the protein tyrosine phosphatase 1B (PTP1B) is a valuable target, can be used to develop significant antidiabetic molecules. Objective: In the present investigation, computational methods and biological evaluation studies have been applied to develop novel PTP1B inhibitors with good enzyme binding affinity and activity. Methods: Virtual screening (docking) analysis of SPECS database compounds on PTP1B enzyme was performed using Schrodinger software. In vitro and in vivo biological evaluations had been conducted with the identified hits. Results: The results revealed that the molecules identified through these studies have shown significant interactions with the active site residues of the PTP1B enzyme. The compounds S1 and S2 provided significant binding interactions with the residues (Arg221 and Gln262) and have shown considerable in vitro PTP1B inhibitory activity and in vivo antidiabetic activity. The compounds S1 and S2 possessed 35.44±0.12% and 33.68±0.08% inhibitory activities, respectively. Conclusion: These identified hits will be used as a template for design and development of novel PTP1B inhibitors with a compatible pharmacokinetic profile.

EGFR Inhibitors and Apoptosis Inducers : Design, Docking, Synthesis, and Anticancer Activity of Novel Tri-Chalcone Derivatives

Estrogen receptors (ERs) are primarily expressed in cancer cells and interfere with the epidermal growth factor (EGFR) signal pathway. However, data are limited regarding the interaction between cytoplasmic ER expression and EGFR-tyrosine kinase inhibitor response. The objective of this study was to design multi-target molecules for enhancing anti-cancer activity and decreasing drug resistance. Two distinct series of tri-chalcone derivatives S1(1-7), S2(1-7) with promising anti-cancer activity was incorporated into the current study. Compounds S1(1-2) and S2(1-2) demonstrated the highest binding affinity for interactions with the active EGFR binding site. Interestingly, compounds S1-1 and S1-2 have shown a potent cytotoxicity of MCF-7 (2.23 ± 0.11 and 2.04 ± 0.71 µM) and MDA-MB-231 (6.44 ± 0.01 and 3.75 ± 0.26 µM), respectively, relative to tamoxifen IC50 of 9.3 ± 0.44 and 18.92 ± 1.43 µM. Thus, in-vitro EGFR activity was evaluated for compounds S1-1 and S1-2. The results indicated that compounds S1-1 and S1-2 showed a significant improvement in the anti-cancer resistant treatment due to their potential effects on the EGFR and the possible anti-ER effect.

N,N′-dialkyl-2-thiobarbituric acid based sulfonamides as potential SARS-CoV-2 main protease inhibitors

An efficient methodology was developed to generate novel N,N′-dialkyl-2-thiobarbituric acid based sulfonamides S1–S4 in good to excellent yields (84%–95%). The synthesized compounds S1–S4 were docked to screen their in silico activities against two enzymes i.e., SARS-CoV-2 main protease enzyme with unliganded active site (2019-nCoV, coronavirus disease 2019, COVID-19) PDB ID: 6Y84 and SARS-CoV-2 Mpro PDB ID: 6LU7. Furthermore, some in silico physicochemical and physicokinetic properties were evaluated using the OSIRIS Property Explorer, Molinspiration property calculator, ADMET property calculator, and GUSAR to assess these compounds as potential candidates as lead compounds for the quest of SARS-CoV-2 main protease inhibitors. Molecular docking analyses of the synthesized compounds predicted that compound S3 is more potent as SARS-CoV-2 main protease inhibitor with binding energy –11.65 kcal/mol in comparison with reference inhibitor N3 (–10.95 kcal/mol), whereas compounds S1, S2, and S4 recorded comparable binding energies –9.89, –10.84, and –10.94 kcal/mol with reference inhibitor N3, which were much better than remdesivir (–9.85 kcal/mol). In case of SARS-CoV-2 Mpro, all compounds S1–S4 with docking energy values of –7.28, –8.38, –8.31, and –7.34 kcal/mol, respectively, were found to be potent in comparison with reference inhibitor N3 (–6.31 kcal/mol) and remdesivir (–6.33 kcal/mol). Ligand efficiency values against the target SARS-CoV-2 proteins, as well as α-glucosidase and DNA-(apurinic or apyrimidinic site) lyase inhibition results of these newly synthesized compounds, were also found to be promising.

In-silico molecular docking study of some n-substituted thiazoles derivatives as FabH inhibitors

Heterocyclic compounds with thiazole moiety are one of the most promising compounds in the medicinal chemistry possessing numerous therapeutic activities. The present was designed to study the high throughput in silico screening of 10 designed 2-phenyl-amino thiazole derivatives as a potent FABH inhibitor in Molegro virtual docker software (Version 6.0) using 3iL9 as PDB. The docking results showed mol dock score of -90.94 with four hydrogen bonding for the standard drugs griseofulvin, while on the other hand, N-substituted thiazole derivatives S2, S5, S6, S7, S8, and S9 exhibited excellent mol dock score, ranged from -102.612 to -144.236, hydrogen bonding (4-10), and docking score ranged from -104.873 to -143.593. Similarly, another in silico study was done using online PASS software and the compounds S1, S2, S5, S6, S7, S8, and S9 have Pa ranged between 0.310 to 0.411 and showed good antibacterial activity whereas, compounds having Pa ranged between 0.216 to 0.334 demonstrated potent antifungal activity when compared to standard drugs. Thus, the present study affirmed the significant antimicrobial potential of some designed N-substituted thiazole derivatives based on their mol dock values and other parameters when studies in silico and the obtained results will provide data support and offer perspectives in future researches to develop potent antimicrobial agents from these N-substituted thiazole derivatives.

Synthesis and biological investigation of triazolopyridinone derivatives as potential multireceptor atypical antipsychotics

A series of triazolopyridinone derivatives originating from the antidepressant trazodone was designed and pharmacologically evaluated. Most of the compounds with a multireceptor functional profile exhibited high potency at the D2, 5-HT1A, and 5-HT2A receptors. Compounds S1, S3, S9 and S12 were selected for further evaluation of druggable potential. Among these compounds, S1, as a D2 receptor partial agonist, demonstrated very potent inhibition of quipazine-induced head-twitch response, which validated its 5-HT2A receptor antagonistic efficacy in vivo. S1 also demonstrated a dose-dependent effect on PCP-induced hyperactivity when administered orally. Thus, S1 endowed with a triazolopyridinone scaffold represents a valuable lead for the development of novel atypical antipsychotics.

Synthesis and Biological Evaluation of Five-Atom-Linker-Based Arylpiperazine Derivatives with an Atypical Antipsychotic Profile.

Herein we describe a focused set of new arylpiperazine derivatives as potential broad-spectrum antipsychotics. The general structure contains a quinolinone-like moiety, an arylpiperazine moiety, and a five-atom linker. Among them, 7-(5-(4-(benzo[d]isothiazol-4-yl)piperazin-1-yl)pentyl)quinolin-2(1H)-one (S6) shows a promising preclinical profile. Compound S6, characterized by partial D2 R agonism, 5-HT1A R agonism, 5-HT2A R antagonism, and blockade of SERT activities, was found to decrease psychosis- and depressive-like symptoms in rodents. The polypharmacological profile of S6 could provide opportunities for the treatment of various other central nervous system disorders such as anxiety, depression, and psychoses associated with dementia. Furthermore, S6 demonstrated acceptable safety, toxicology, and pharmacokinetic profiles, and has been selected as a preclinical candidate for further evaluation in schizophrenia.

Insights into the c-Jun N-terminal kinase 3 (JNK3) inhibitors: CoMFA, CoMSIA analyses and molecular docking studies

JNK3, a protein kinase of the MAPK family that is potently activated by a variety of environmental stress and pro-inflammatory cytokines, has been recognized as an important therapeutic target for several neurodegenerative diseases. However, due to the long development cycle and the cost of R&D, no related drugs have been released. By applying the CoMFA and CoMSIA methods, QSAR models that explore the structure-activity relationship of the JNK3 inhibitors are established and validated, the parameters are satisfactory (q2 = 0.774, r2 = 0.991 for CoMFA model and q2 = 0.666, r2 = 0.990 for CoMSIA model) and base on which a series of novel molecules are designed. Molecular docking is conducted to verify the potential of the new compounds, the results shows promising activity. We speculated that the series of compounds S1–S11 might have some therapeutic activity in the c-jnk3 pathway, particularly the “S8” may prove to be the best one, which provided useful guidance for the design of new and efficient subtype selective JNK3 inhibitors.

Synthesis and characterization of new 4,5-dihydropyrazol-1-yl derivatives

In this study, first, a series of chalcone compounds S1–S6 were synthesized from various acetophenone derivatives (acetophenone, p-methyl acetophenone, and p-methoxy acetophenone) and aromatic aldehyde derivatives (benzaldehyde, p-methyl benzaldehyde, and p-methoxy benzaldehyde) by the Claisen–Schmidt condensation reaction. These S1–S6 compounds were then used in the preparation of 4,5-dihydropyrazol-1-yl derivatives S7–S15. Finally, four new compounds S16–S19 were synthesized from compound (S7, S8, S9, and S12) and 2,4-dinitrophenylhydrazine. Therefore, three known and ten new heterocyclic compounds were synthesized and completely characterized using 1H NMR, 13C NMR, IR, and elemental analysis.

SYNTHESIS AND ANTICANCER ACTIVITY OF NOVEL 2-BENZYL-6- (SUBSTITUTED PHENYL)-IMIDAZO[2,1-B] [1,3,4] THIADIAZOLE DERIVATIVES

A new series of 2-benzyl-6-(substituted phenyl)-imidazo[2,1-b][1,3,4] thiadiazoles (S1-S8) was synthesized as potential anti-cancer agents. These compounds were evaluated for their anticancer activity against various cancer cell lines. The anticancer activity data reveals that the compounds S1 (2-benzyl- 6-phenylimidazo[2,1-b][1,3,4]thiadiazole) showed maximum growth inhibition against CNS cancer cell lines while the compounds S2 (2-benzyl-6-(4-chlorophenyl) imidazo[2,1-b][1,3,4] thiadiazole) and S3 (2-benzyl-6-(2,4-dichlorophenyl)imidazo[2,1-b][1,3,4] thiadiazole) showed maximum inhibition against leukemia cell lines. The compounds S5 (2-(2-benzylimidazo[2,1-b] [1,3,4]thiadiazol-6-yl) phenol) and S6 (4-(2-benzylimidazo[2,1-b][1,3,4] thiadiazol-6-yl)benzene-1,3-diol) showed maximum inhibition against renal cancer cell lines and the compound S7 (3-(2-benzylimidazo[2,1-b][1,3,4] thiadiazol-6-yl) benzenamine) was most active against non-small cell lung cancer cell lines.

Design of novel dopamine D2 and serotonin 5-HT2A receptors dual antagonists toward schizophrenia: An integrated study with QSAR, molecular docking, virtual screening and molecular dynamics simulations

The extrapyramidal side effects of schizophrenia treatment can be significantly reduced by simultaneously targeting dopamine D2 and serotonin 5-HT2A receptors. In this study, three-dimensional quantitative structure–activity relationship (3D-QSAR) models of D2 receptor (CoMFA-1, q2 = 0.767, r2 = 0.969; CoMSIA-1, q2 = 0.717, r2 = 0.978) and 5-HT2A receptor antagonists (CoMFA-2, q2 = 0.703, r2 = 0.946; CoMSIA-2, q2 = 0.675, r2 = 0.916) were successfully constructed using 35 tetrahydropyridopyrimidinone derivatives. Topomer CoMFA and HQSAR models were then constructed to further validate and supplement above models. Results showed that all models had good predictive power and stability. Contour map analysis revealed that the electrostatic and hydrophobic fields played vital roles in the bioactivity of dual antagonists. Molecular docking and molecular dynamic studies also suggested that the hydrogen bonding, electrostatic and hydrophobic interactions played key roles in the formation of stable binding sites. Meanwhile, several key residues like ASP114, TRP100, PHE389 of dopamine D2 receptor and ASP134, PHE328, TRP324 of serotonin 5-HT2A receptor were identified. Based on above findings, seven compounds were obtained through bioisostere replacement and ten compounds were designed by contour map analysis, in which the predicted activity of compounds S6 and DS2 were equivalent to that of the template compound 15. 3D-QSAR and ADMET predictions indicated that all newly designed compounds had great biological activity and physicochemical properties. Moreover, based on the best pharmacophore model, four compounds (Z1, Z2, Z3 and Z4) with new backbones were obtained by virtual screening. Overall, this study could provide theoretical guidance for the structural optimization, design and synthesis of novel dopamine D2 and serotonin 5-HT2A receptors dual antagonists.Abbreviations3D-QSARThree-dimensional quantitative structure–activity relationship5-HT2ARSerotonin 5-hydroxytryptamine 5-HT2A receptor5-HT2CRSerotonin 5-hydroxytryptamine 5-HT2C receptor receptorCADDComputer-aided drug designCoMFAComparative molecular field analysisCoMSIAComparative molecular similarity index analysisD2RDopamine D(2) receptorGPCRG-protein coupled receptorPLSPartial least squares regressionHQSARHologram quantitative structure–activity relationship.Communicated by Ramaswamy H. Sarma

Graph Theoretical Analysis, In Silico Modeling, Synthesis, Anti-Microbial and Anti-TB Evaluation of Novel Quinoxaline Derivatives.

We designed to synthesize a number of 2-(2-(substituted benzylidene) hydrazinyl)-N-(4-((3-(phenyl imino)-3,4-dihydro quinoxalin-2(1 H)-ylidene)amino) phenyl) acetamide S1-S13: with the hope to obtain more active and less toxic anti-microbial and anti-TB agents. A series of novel quinoxaline Schiff bases S1-S13: were synthesized from o-phenylenediamine and oxalic acid by a multistep synthesis. In present work, we are introducing graph theoretical analysis to identify drug target. In the connection of graph theoretical analysis, we utilised KEGG database and Cytoscape software. All the title compounds were evaluated for their in-vitro anti-microbial activity by using agar well diffusion method at three different concentration levels (50, 100 and 150 µg/ml). The MIC of the compounds was also determined by agar streak dilution method. The identified study report through graph theoretical analysis were highlights that the key virulence factor for pathogenic mycobacteria is a eukaryotic-like serine/threonine protein kinase, termed PknG. All compounds were found to display significant activity against entire tested bacteria and fungi. In addition the synthesized scaffolds were screened for their in vitro antituberculosis (anti-TB) activity against Mycobacterium tuberculosis (Mtb) strain H37Ra using standard drug Rifampicin. A number of analogs found markedly potent anti-microbial and anti-TB activity. The relationship between the functional group variation and the biological activity of the evaluated compounds were well discussed. The observed study report was showing that the compound S6: (4-nitro substitution) exhibited most potent effective anti-microbial and anti-TB activity out of various tested compounds.