Design,synthesis of new novel quinoxalin-2(1H)-one derivatives incorporating hydrazone,hydrazine, and pyrazole moieties as antimicrobial potential with in-silico ADME and molecular docking simulation

A series of 6-(morpholinosulfonyl)quinoxalin-2(1H)-one based hydrazone, hydrazine, and pyrazole moieties were designed, synthesized, and evaluated for their in vitro antimicrobial activity. All the synthesized quinoxaline derivatives were characterized by IR, NMR (¹H /¹³C), and EI MS. The results displayed good to moderate antimicrobial potential against six bacterial, and two fungal standard strains. Among the tested derivatives, six quinoxalin-2(1H)-one derivatives 4a, 7, 8a, 11b, 13, and 16 exhibited a significant antibacterial activity with MIC values (0.97–62.5 µg/mL), and MBC values (1.94–88.8 µg/mL) compared with Tetracycline (MICs = 15.62–62.5 µg/mL, and MBCs = 18.74–93.75 µg/mL), and Amphotericin B (MICs = 12.49–88.8 µg/mL, and MFC = 34.62–65.62 µg/mL). In addition, according to CLSI standards, the most active quinoxalin-2(1H)-one derivatives demonstrated bactericidal and fungicidal behavior. Moreover, the most active quinoxaline derivatives showed a considerable antibacterial activity with bactericidal potential against multi-drug resistance bacteria (MDRB) strains with MIC values ranged between (1.95–15.62 µg/mL), and MBC values (3.31–31.25 µg/mL) near to standard Norfloxacin (MIC = 0.78–3.13 µg/mL, and MBC = 1.4–5.32 µg/mL. Further, in vitro S. aureus DNA gyrase inhibition activity were evaluated for the promising derivatives and displayed potency with IC₅₀ values (10.93 ± 1.81–26.18 ± 1.22 µM) compared with Ciprofloxacin (26.31 ± 1.64 µM). Interestingly, these derivatives revealed as good immunomodulatory agents by a percentage ranging between 82.8 ± 0.37 and 142.4 ± 0.98 %. Finally, some in silico ADME, toxicity prediction, and molecular docking simulation were performed and showed a promising safety profile with good binding mode.     

One-pot multicomponent synthesis of novel 3, 4-dihydro-3-methyl-2(1H)-quinazolinone derivatives and their biological evaluation as potential antioxidants,enzyme inhibitors,antimicrobials, cytotoxic and anti-inflammatory agents

A series of novel 3, 4-dihydro-3-methyl-2(1H)-quinazolinone derivatives with substituted amine moieties (1–13) and substituted aldehyde (S) were designed and synthesized by a reflux condensation reaction in the presence of an acid catalyst to get N-Mannich bases. Mannich bases were evaluated pharmacologically for their antioxidant, α-amylase enzyme inhibition, antimicrobial, cell cytotoxicity and anti-inflammatory activities. Most of the compounds exhibited potent activities against these bioassays. Among them, SH1 and SH13 showed potent antioxidant activity against DPPH free radical at IC₅₀ of 9.94 ± 0.16 µg/mL and 11.68 ± 0.32 µg/mL, respectively. SH7, SH10 and SH13 showed significant results in TAC and TRP antioxidant assays, comparable to that of ascorbic acid. SH2 and SH3 showed potent activity in inhibiting α-amylase enzyme at IC₅₀ of 10.17 ± 0.23 µg/mL and 9.48 ± 0.17 µg/mL, respectively, when compared with acarbose (13.52 ± 0.19 µg/mL). SH7 was the most active against gram-positive and gram-negative bacterial strains, SH13 being the most potent against P. aeruginosa by inhibiting its growth up to 80% (MIC = 11.11 µg/mL). SH4, SH5 and SH6 exhibited significant activity against some fungal strains. Among the thirteen synthesized compounds (SH1-SH13), four were screened out based on the results of brine shrimp lethality assay (LD₅₀) and cell cytotoxicity assay (IC₅₀), to determine their anti-cancer potential against Hep-G2 cells. The study was conducted for 24, 48, and 72 h. SH12 showed potent results at IC₅₀ of 6.48 µM at 72 h when compared with cisplatin (2.56 µM). An in vitro nitric oxide (NO) assay was performed to shortlist compounds for in vivo anti-inflammatory assay. Among shortlisted compounds, SH13 exhibited potent anti-inflammatory activity by decreasing the paw thickness to the maximum compared to the standard, acetylsalicylic acid (ASA).     

Synthesis and in vitro anti-proliferative capabilities of steroidal thiazole and indole derivatives

Derivatives (1–15) of steroidal and indole class were synthesized using different strategies. These compounds were characterized by ¹H NMR spectroscopy and EI-MS, respectively. The synthetic derivatives were examined for their cytotoxic effects on human adenocarcinoma cells (HCT-116) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and morphometric analysis. The cytotoxic effects of all the compounds were observed after 48 h treatment and it was found that out of fifteen, four compounds 1, 2, 3, and 14 showed inhibitory action on the cancer cells. We have calculated the IC₅₀ values for compounds 1, 2, 3, and 14 which were 22.50 µg/mL, 55.65 µg/mL, 21.35 µg/mL and 58.50 µg/mL, respectively. The compounds 3 (IC₅₀ = 21.35 µg/mL) and 1 (IC₅₀ = 22.50 µg/mL) showed highest inhibitory activities as compared to compounds 2 (IC₅₀ = 55.65 µg/mL) and 14 (IC₅₀ = 58.50 µg/mL). These results suggested that steroidal thiazole and indole derivatives are potent lead molecules having strong anti-cancer proliferative capabilities.     

The design of fluoroquinolone-based cholinesterase inhibitors: Synthesis,biological evaluation and in silico docking studies

An enhanced acetylcholinesterase (AChE) activity is a hallmark in early stages of Alzheimer's ailment that results in decreased acetylcholine (ACh) levels, which in turn leads to cholinergic dysfunction and neurodegeneration. Consequently, inhibition of both AChE and butyrylcholinesterase (BChE) is important to prolong ACh activity in synapses for the enhanced cholinergic neurotransmission. In this study, a series of new fluoroquinolone derivatives (7a-m) have synthesized and evaluated for AChE and BChE inhibitory activities. The screening results suggested that 7 g bearing ortho fluorophenyl was the most active inhibitor against both AChE and BChE, exhibiting IC₅₀ values of 0.70 ± 0.10 µM and 2.20 ± 0.10 µM, respectively. The structure–activity relationship (SAR) revealed that compounds containing electronegative functions (F, Cl, OMe, N and O) at the ortho position of the phenyl group exhibited higher activities as compared to their meta- and/or para substituted counterparts. Molecular docking studies of synthesized compounds 7a, 7g, 7j and 7l docked into the active site of AChE and 7a-f docked into the active site of BChE revealed that these compounds exhibited conventional H-bonding along with π-π interaction with the active residues of AChE through their electronegative functions and phenyl ring, respectively. All the synthesized compounds are characterized by spectroscopic methods including FT-IR, ¹H- and ¹³C NMR as well as elemental analysis. This is the first example of fluoroquinolone-based cholinesterase inhibitors.     

Synthesis,characterization, biological evaluation and molecular docking studies of 2-(1H-benzo[d]imidazol-2-ylthio)-<Emphasis Type="Italic">N</Emphasis>-(substituted 4-oxothiazolidin-3-yl) acetamides

Background

A series of 2-(1H-benzo[d]imidazol-2-ylthio)-N-(substituted 4-oxothiazolidin-3-yl) acetamides was synthesized and characterized by physicochemical and spectral means. The synthesized compounds were evaluated for their in vitro antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans and Aspergillus niger by tube dilution method. The in vitro cytotoxicity study of the compounds was carried out against human colorectal (HCT116) cell line. The most promising anticancer derivatives (5l, 5k, 5i and 5p) were further docked to study their binding efficacy to the active site of the cyclin-dependent kinase-8.

Results

All the compounds possessed significant antimicrobial activity with MIC in the range of 0.007 and 0.061 µM/ml. The cytotoxicity study revealed that almost all the derivatives were potent in inhibiting the growth of HCT116 cell line in comparison to the standard drug 5-fluorouracil. Compounds 5l and 5k (IC₅₀ = 0.00005 and 0.00012 µM/ml, respectively) were highly cytotoxic towards HCT116 cell line in comparison to 5-fluorouracil (IC₅₀ = 0.00615 µM/ml) taken as standard drug.

Conclusion

The molecular docking studies of potent anticancer compounds 5l, 5k, 5i and 5p showed their putative binding mode and significant interactions with cyclin-dependent kinase-8 as prospective agents for treating colon cancer.

     

Synthesis,in vitro evaluation,and molecular docking studies of benzofuran based hydrazone a new inhibitors of urease

This work has described the synthesis of novel class (1–25) of benzofuran based hydrazone. The hybrid scaffolds (1–25) of benzofuran based hydrazone were evaluated in vitro, for their urease inhibition. All the newly synthesized analogues (1–25) were found to illustrate moderate to good urease inhibitory profile ranging from 0.20 ± 0.01 to 36.20 ± 0.70 µM. Among the series, compounds 22 (IC₅₀ = 0.20 ± 0.01 µM), 5 (IC₅₀ = 0.90 ± 0.01 µM), 23 (IC₅₀ = 1.10 ± 0.01 µM) and 25 (IC₅₀ = 1.60 ± 0.01 µM) were found to be the many folds more potent than thiourea as standard inhibitor (IC₅₀ = 21.86 ± 0.40 µM). The elevated inhibitory profile of these analogues might be due to presence of dihydroxy and flouro groups at different position of phenyl ring B attached to hydrazone skeleton. These dihydroxy and fluoro groups bearing compounds have shown many folds better inhibitory profile through involvement of oxygen of dihydroxy groups in hydrogen bonding with active site of enzymes. Various types of spectroscopic techniques such as ¹H-, ¹³C- NMR and HREI-MS spectroscopy were used to confirm the structure of all the newly developed compounds. To find SAR, molecular docking studies were performed to understand, the binding mode of potent inhibitors with active site of enzymes and results supported the experimental data.     

Design,synthesis, antimicrobial evaluations and in silico studies of novel pyrazol-5(4H)-one and 1H-pyrazol-5-ol derivatives

A new series of 1,4-disubstituted 3-methylpyrazol-5(4H)-one derivatives were synthesized by reacting various substituted aromatic aldehydes with 3-methylpyrazol-5(4H)-one derivatives through Knoevenagel condensation by conventional as well as by exposure to microwave irradiations. After that newly synthesized compounds of 1,4-disubstituted 3-methyl-1H-pyrazol-5-ol were prepared from these derivatives by reduction reaction of sodium borohydride at 0–5 °C. Sixty-four heterocyclic compounds containing a pyrazole moiety were synthesized with good to excellent yields (51 to 91%). Compounds (3d, 3m, 4a, 4b, 4d, and 4g) showed potent antibacterial activity against MSSA (Methicillin-susceptible strains of Staphylococcus aureus) and MRSA (Methicillin-resistant strains of Staphylococcus aureus) with MIC (the minimum inhibitory concentration) ranging between 4 and 16 µg/mL as compared to ciprofloxacin (MIC = 8–16 µg/mL). Compounds (4a, 4h, 4i, and 4l) showed potent antifungal activity against Aspergillus niger with MIC ranging between 16 and 32 µg/mL as compared to fluconazole (MIC = 128 µg/mL). In particular, compound 4a exhibited the strongest activity among the synthesized compounds in both bacterial and fungal strains with MIC ranging between 4 and 16 µg/mL. Furthermore, the nine most active compounds showed a good ADMET (absorption, distribution, metabolism, excretion, and toxicity) profile in comparison to ciprofloxacin and fluconazole as reference drugs. Molecular docking predicted that DHFR (dihydrofolate reductase) protein from Staphylococcus aureus and NMT (N-myristoyl transferase) protein from Candida albicans are the most suitable targets for the antimicrobial activities of these potent compounds.     

Multistep synthesis and screening of heterocyclic tetrads containing furan,pyrazoline, thiazole and triazole (or oxadiazole) as antimicrobial and anticancer agents

In the present study novel heterocyclic tetrads containing furan, pyrazoline, thiazole and triazole (or oxadiazole) (1, 2, 3, 4a-e and 5a-e) were designed and synthesized and investigated for their antimicrobial (against selected bacteria and fungi) and anticancer potential. The molecules 4e and 5e containing 4-fluoro phenyl and 4-fluoro benzyl substituents showed promising antimicrobial (antibacterial and antifungal activities with MICs ranging between 0.5 and 8 µg/mL. Compounds 3 exhibited potent anticancer activity with an IC₅₀ value of 0.49 ± 1.45 µM against the human gastric cancer cell line (BGC-823) whereas compound 4e displayed an IC₅₀ value of 0.65 ± 0.53 µM against breast cancer (MCF-7) cell line respectively. All compounds showed selective toxicity against the cancer cell lines compared to human normal liver cell lines. Molecular docking studies of the most potent compounds (3 and 4e) against selected microbial and cancer proteins revealed the crucial binding interactions of the potent compounds with the target enzymes. Compounds 3 and 4e are promising lead molecules to be developed as potential drug candidates.     

Synthesis and cytotoxic activity of new indolylpyrrole derivatives

The current approach described the synthesis of a new series of indolylpyrrole derivatives through multicomponent reaction of α-cyano chalcones, appropriate aldehydes, and ammonium acetate in refluxed acetic acid. The chemical structures of the designed compounds were confirmed with spectroscopic data and elemental analysis and then tested for their in vitro cytotoxic activity by SRB assay method towards three cell lines involving human Prostate adenocarcinoma; metastatic cells (PC-3), human ovary adenocarcinoma (SKOV3) and human dukes' type B, colorectal adenocarcinoma (LS 174 T). Most significant activity provided with compounds 5c, 5h and, 5j against prostate cancer cells (PC-3) with IC50s of 3.30 ± 0.20, 3.60 ± 0.10, and 3.60 ± 0.90 µg/ml, respectively. In human ovarian carcinoma (SKOV3), the compounds 5a, and 5i have stronger cytotoxicity with IC50s of 1.20 ± 0.04, 1.90 ± 0.50 µg/ml, respectively than the standard doxorubicin (IC50 = 2.20 ± 0.02 µg/ml). On the other hand, only compound 5a has the ability to diminish the viability of LS174T cells in an active manner with IC50 2.80 ± 0.10 µg/ml. Consequently, this effort offers groundwork for additional examination of nominated indolylpyrroles as antiproliferative agents.     

Design,synthesis, characterization,and antimicrobial evaluation of some new pyridine and chromene derivatives containing Lidocaine analogue

In an attempt to find a new class of antimicrobial agents, a series 2-pyridinone and 2-iminochromene derivatives containing Lidocaine analogue were designed and synthesized. The 2-pyridinone derivatives (3), (4), and (6) were obtained through the cyclocondensation of 2-cyano-N-(2,6-dimethylphenyl)-acetamide (2) with 1,3-dicarbonyl compounds and/or ternary condensation of (2), aromatic aldehyde, and malononitrile. Also, a series of 2-iminochromene derivatives (7–9) were synthesized through the condensation reaction of cyanoacetamide derivative (2) with salicylaldehyde derivatives. The structure of the new compounds were confirmed based on elemental analysis and spectral data. These compounds were screened for their antibacterial and antifungal activity The minimal inhibitory concentration (MIC) (µg/mL) of the most active (4), (5b), and (8) derivatives were determined. The MIC values between 7.81 and 31.26 µg/mL against bacterial species for (8) derivative, and upon comparison to tetracycline exhibited a positive control MIC (31.26–62.6 µg/mL). Besides, the activity against C. albicans (ATCC 1023) showed a MIC value of 15.63 µg/mL, which is similar to that of Amphotericin B.     

Synthesis and characterization of some tetrazoles and their prospective for aerobic micro-fouling mitigation

Two series of tetrazole derivatives of the type N-(1H-tetrazol-5-yl)-1-(aryl)methanimine (101–106) and 1-(4-alkoxyphenyl)-N-(1H-tetrazol-5-yl)methanimine (107–111) were synthesized and characterized via conventional tools of analysis (elemental analysis, FT-IR and ¹H NMR spectroscopy). These two synthesized series were biologically evaluated for their potentials against some microbial biofilm causing strains (micro bio-foulants). Biological activities were evaluated by MIC values and cell viability percentages of them. In case of compounds (107–111), 107 was the most potent antimicrobial one, where its MIC values were 10.666667 µg/ml; 12.82222 µg/ml and 21.43666 µg/ml for Staphylococcus aureus, Escherichia coli and Candida albicans respectively, whereas compound 106, (of group 101–106), MIC values were 16 µg/ml for all the tested microorganisms. Viability assay showed that 107 activity percentages were 96.99456%, 92.32886% and 89.09558% against Gm +ve bacteria, Gm −ve bacteria and yeast respectively, whereas 106 activity percentages were 95.255569%, 90.204675% and 86.710956% against Gm +ve bacteria, Gm −ve bacteria and yeast respectively. Two antimicrobial mode of actions were proposed and discussed depending on the two evaluated tetrazole groups.     

Antitubercular and antioxidant activities of hydroxy and chloro substituted chalcone analogues: Synthesis,biological and computational studies

A series of chalcone analogues (1–15) were synthesized by Claisen-Schmidt condensation in good yields (70–95%) and characterized by FT-IR, ¹H NMR and mass spectral methods. Additionally, compounds 3 and 7 were characterized by ¹³C NMR. Antitubercular and antioxidant activities of the chalcones were evaluated by MABA and DPPH free radical assays. In MABA assay analogues 3 (MIC = 14 ± 0.11 µM) and 11 (MIC = 14 ± 0.17 µM) bearing fluorine and methoxy groups at para and meta positions were 1.8-times more active than the standard pyrazinamide (MIC = 25.34 ± 0.22 µM). The chalcone analogues such as compound 7 (IC₅₀ = 4 ± 1 µg/mL) containing electron releasing groups such as OH at ortho position had slightly more antioxidant activity than Gallic acid (IC₅₀ = 5 ± 1 µg/mL). The potential compounds 3, 7, 9 and 11 were less selective and toxic against human live cell lines-LO2. Further, molecular docking results of chalcones against anti-tubercular drug target isocitrate lyase (PDB ID: 1F8M) revealed that compound 3 and 11 shown least binding energies as ?7.6, and ?7.5 kcal/mol are in line with in vitro MABA assay, suggesting that these compounds 3 and 11 are strong inhibitor of isocitrate lyase. SwissADME programme estimated the drug likeliness properties of compounds 3, 7, 9 and 11. The lead molecules arisen through this study helps to develop new antitubercular and antioxidant agents.     

Design,synthesis, biological evaluation and in silico studies of novel 1,2,3-triazole linked benzoxazine-2,4-dione conjugates as potent antimicrobial,antioxidant and anti-inflammatory agents

In an attempt to rationalize the search for new potential anti-inflammatory and anti-infection agents, a new series of 1,4-and 1,5-disubstituted 1,2,3-triazoles linked benzoxazine conjugates have been synthesized via “Click Chemistry” reaction, were designed, synthesized and characterized by means of spectral and elemental data. The newly synthesized compounds have been assessed for their antimicrobial, antioxidant and anti-inflammatory potential. Results revealed that all synthesized compounds display superior activities to the standard drug against different bacterial strains especially S. aureus, M. luteus, and P. aeruginosa, with good to moderate activity towards the tested E. coli bacteria, in respect to the commercial antibiotic, tetracycline. Moreover, the antifungal activity was screened against C. albicans and C. krusei yeasts and results demonstrate potent activity as compared to the standard drug, ampicillin. The antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assays, whose results indicate that analogues 4a (IC₅₀ 1.88 ± 0.07 µM and 2.17 ± 0.02) followed by 4b (IC₅₀ 2.19 ± 0.09 µM and 2.38 ± 0.43 µM), 4d (IC₅₀ 2.30 ± 0.01 µM and 4.07 ± 0.57 µM), and 4f (2.98 ± 0.02 µM and 3.80 ± 0.01 µM), respectively, exhibited the strongest activity when compared to the standard reference, butylated hydroxytoluene (BHT) (3.52 ± 0.08 µM and 4.64 ± 0.11 µM). In addition, their anti-inflammatory activity was assessed using the xylene-induced ear edema standard technique and the results demonstrated the potency of 4a, 4b and 4d as excellent anti-inflammatory agents. Preliminary structure–activity relationship studies (SARs) provide those biological activities can be modulated by the presence of unsubstituted aromatic ring as well as the position of substituents on the phenyl moiety via electron withdrawing groups (EWGs) or electron donating groups (EDGs) effects. Docking studies on the most promising compounds 4a, 4b, and 4d into the active sites of S. aureus tyrosyl-tRNA synthetase, Candida albicans N-Myristoyltransferase, Human COX-2 enzyme, and Human Peroxiredoxin 5 revealed good binding profiles with the target proteins. The interaction's stability was further assessed using a conventional atomistic 100 ns dynamic simulation study. Hence, our results recommended the rationalized targets 4a, 4b and 4d, to be promising lead candidates for the discovery of novel dual anti-inflammatory and anti-infection agents.     

Synthesis and in vitro anticancer,antibacterial, and antioxidant studies of unsymmetrical Schiff base derivatives of 4-[(1<Emphasis Type="Italic">E</Emphasis>)-<Emphasis Type="Italic">N</Emphasis>-(2-aminoethyl)ethanimidoyl]benzene-1,3-diol

Schiff bases such as 2-hydroxy-1-(4-hydroxyphenyl)ethanone (DHAP) and its derivatives have attracted attention because they are useful in design and development of novel organic compounds for potential pharmaceutical applications. In this work, a series of 4-[(1E)-N-(2-aminoethyl)ethanimidoyl]benzene-1,3-diol (4a–h) Schiff bases were synthesized by reaction of ethylenediamine, DHAP, and appropriate aldehyde moieties. The compositions of the prepared compounds were established using elemental analysis and Fourier-transform infrared (FTIR) and ultraviolet–visible (UV–Vis) spectroscopies. The compounds were screened against three Gram-positive and three Gram-negative bacteria, and the results compared with standard drugs ciprofloxacin and amoxicillin. Compounds 4g, 4h were found to have higher activity against Staphylococcus aureus with minimum inhibitory concentration (MIC) value of 2.5 mg/mL, while compounds 4f and 4h inhibited Escherichia coli with MIC values of 2.5 and 5 mg/mL, respectively. The IC₅₀ values of compounds 4a–h for scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical ranged from 2.63 ± 0.79 to 3.85 ± 0.83 µM with good correlation coefficient of R ² = 0.957–0.994. In vitro anticancer screening of the compounds showed that compounds 4f, 4h, and parthenolide efficiently affected cell viability of cancer cell line MCF-7 with IC₅₀ values of 4.10 ± 1.32, 4.01 ± 2.26, and 0.44 ± 2.02 µM, respectively.     

Quinoline conjugated 2-azetidinone derivatives as prospective anti-breast cancer agents: In vitro antiproliferative and anti-EGFR activities,molecular docking and in-silico drug likeliness studies

Two series [1–8 (series-1) and 9–16 (series-2)] of quinoline conjugated 2-azetidinones were evaluated for their antiproliferative potential against breast cancer cell lines MCF7 and MDA-MB-231 respectively. All the compounds were more active towards against MCF7 than MDA-MB-231 cancer cell lines and few compounds activity was more than the standard erlotinib. For instance, the compound 16 of series-2 bearing electron withdrawing fluorine atom at the 6th position of quinoline ring showed promising activity with MIC values of 2.33 ± 0.19 µg/mL for MCF7 and 4.19 ± 0.22 µg/mL for MDA-MB-231 cells, respectively. In a similar way, the compounds 8 and 14 containing fluorine and chlorine substituents respectively, and located at position-6 of quinoline scaffold showed better activity than erlotinib. The ability of target compounds to inhibit EGFR tyrosine kinase, one of the key enzymes involved in breast carcinomas was evaluated by in vitro enzymatic assay and it was found that the compound 8 had close inhibitory activity to erlotinib with an %inhibition of 97.1 ± 0.08 at 10 µM. The compounds showed selective toxicity on the cancer cell lines as their IC₅₀ values are high against the human normal liver cell line-LO2. Further, the docking studies of the promising compounds 8, 14 and 16 revealed the important molecular interactions with the EGFR kinase enzyme (PDB ID: 6S9B). The physicochemical and pharmacokinetic properties of the most active compounds were predicted using Swiss ADME and pkCSM tools respectively. The most promising compounds arisen from the present study can be considered as prospective lead molecules for anticancer activity against breast carcinoma.     

Microwave assisted synthesis of 2-amino-4-chloro-pyrimidine derivatives: Anticancer and computational study on potential inhibitory action against COVID-19

We report microwave synthesis of seven unique pyrimidine anchored derivatives (1–7) incorporating multifunctional amino derivatives along with their in vitro anticancer activity and their activity against COVID-19 in silico. 1–7 were characterized by different analytical and spectroscopic techniques. Cytotoxic activity of 1–7 was tested against HCT116 and MCF7 cell lines, whereby 6 exhibited highest anticancer activity on HCT116 and MCF7 with EC₅₀ values of 89.24 ± 1.36 µM and 89.37 ± 1.17 µM, respectively.Molecular docking was performed for derivatives (1–7) on main protease for SARS-CoV-2 (PDB ID: 6LU7). Results revealed that most of the derivatives had superior or equivalent affinity for the 3CLpro, as determined by docking and binding energy scores. 6 topped the rest with highest binding energy score of ?8.12 kcal/mol with inhibition constant reported as 1.11 µM. ADME, drug-likeness, and pharmacokinetics properties of 1–7 were tested using Swiss ADME tool. Toxicity analysis was done with pkCSM online server.All derivatives showed high GI absorption. Except 1 and 3, all derivatives showed blood brain barrier permeability. Most derivatives showed negative logKp values suggesting derivatives are less skin permeable and bioavailability score of all derivatives was 0.55. The toxicity analysis demonstrated that all derivatives have no skin sensitization properties. 6 and 7 showed maximum tolerated dose (Human) values of ?0.03 and ?0.018, respectively and absence of AMES toxicity.     

Design,synthesis and antiviral activities of chalcone derivatives containing pyrimidine

A series of chalcone derivatives (T1-T23) containing pyrimidine were synthesized, characterized, and assessed for their antiviral activity against tobacco mosaic virus (TMV) activities. Most target compounds displayed better antiviral activities against TMV than commercial ningnanmycin. Among them, the EC₅₀ value of curative activities of compounds T1, T7, T9 and T19 (219.2, 228.2, 279.9 and 234.9 μg/mL, respectively) were superior to that of ningnanmycin (320.1 μg/mL). In addtion, the EC₅₀ value of protective activities of compounds T5, T9, T19 and T23 (235.0, 220.0, 199.5 and 187.2 μg/mL, respectively) were superior to that of ningnanmycin (307.4 μg/mL). Then, the antiviral mechanism of T19 and TMV coat protein (TMV-CP) was preliminarily investigated by microscale thermophoresis (MST) and molecular docking technology. The results showed that T19 had a strong binding affinity for TMV coat protein, and its dissociation constant (K_d) was 0.00310 ± 0.000916 μM, which was superior to ningnanmycin(0.165 ± 0.0799 μM). This study suggests that chalcone derivatives containing pyrimidine could be used as novel antiviral agents for controlling the plant viruses.     

Synthesis,anticancer evaluation,and molecular modeling study of new 2-(phenylamino)pyrazolo[1,5-a]pyrimidine analogues

The reaction of 3-amino-5-phenylaminopyrazoles 2 with 3-(dimethylamino) acrylonitrile derivatives resulted in a series of substituted pyrazolopyrimidine analogues 4 and 6. The DFT studies of the isolated compounds showed that the frontier molecular orbitals energy gap was close and in the 2.65–2.81 eV range where the derivative 6b has the lowest and both of 4a and 4c have the highest values. Meanwhile, the anticancer activity of the newly synthesized pyrazolopyrimidine analogues have been tested against several different cell lines (MCF-7, PC3, Hep-2 and WI38). The investigated pyrazolopyrimidines showed remarkable cytotoxicity activity against the MCF-7 and Hep-2 cell lines. In comparison to the effects of 5-fluorouracil, IC₅₀ = 10.19 ± 0.42 and 7.19 ± 0.47, compounds 6a-c demonstrated potential anticancer activity with IC₅₀ values for MCF-7 (10.80 ± 0.36–19.84 ± 0.49 μM) and Hep-2 (8.85 ± 0.24–12.76 ± 0.16 μM). Important details regarding the protein's binding sites were disclosed when the produced analogues docked with the crystal structure of the KDM5A protein, which was located in the protein data library.     

Synthesis,and biological screening of chloropyrazine conjugated benzothiazepine derivatives as potential antimicrobial,antitubercular and cytotoxic agents

A series of twenty new chloropyrazine conjugated benzothiazepines (22–41) have been synthesized with 58%–95% yields. The compounds were characterized by using different spectroscopic techniques including FT-IR, ¹H NMR, ¹³C NMR spectroscopy and mass spectrometry. The synthesized compounds (22–41) and their precursor chalcones (2–21) were evaluated for antitubercular and cytotoxic activities. Additionally, compounds 22–41 were also tested for antimicrobial activity. Among the chalcone series (2–21), compounds 7 and 14 showed significant antitubercular activities (MICs 25.51 and 23.89 µM, respectively), whereas among benzothiazepines (22–41), compounds 27 and 34 displayed significant antimicrobial (MICs 38.02 µM, 19.01 µM) and antitubercular (MIC 18.10 µM) activities. Compounds 7 and 41 displayed cytotoxic activities with IC₅₀ of 46.03 ± 1 and 35.10 ± 2 µM respectively. All the compounds were evaluated for cytotoxic activity on normal human liver cell lines (L02) and found to be relatively less selective towards this cell line. The most active compounds identified through this study could be considered as potential leads for the development of drugs with possible antimicrobial, antitubercular, and cytotoxic activities.     

Synthesis,characterization and biological evaluation of purine nucleoside analogues

We present a convenient route for the synthesis of C6-amino-C5′-N-cyclopropyl carboxamido-C2-alkynylated purine nucleoside analogues 11a–g via Sonogashira coupling reaction. The nine step synthesis is easy to perform, employing commercially available reagents. Compound 9 is used as key intermediate for the synthesis of analogues 11a–g. Synthetic intermediates and final products are appropriately characterized by IR, ¹H NMR, ¹³C NMR and Mass. The modified nucleoside analogues 11a–g is evaluated for in vitro anticancer activity against MDA-MB-231 and Caco-2 cell lines. Screening data reveals that compounds 11b and 11e displayed potent IC₅₀ value of 7.9, 6.8 µg/mL respectively against MDA-MB-231 and of 7.5, 8.3 µg/mL respectively against Caco-2 than the standard drug doxorubicin, thus establishing the potential anti-cancer properties of these newer derivatives.