Compounds 4m Research Articles

Exploring monocyclic core: Discovery of pyrrol-2-one derivatives as a new series of potent MCHR1 antagonists with in vivo efficacy

With an objective to improve the profiles of the 1st generation non-basic MCHR1 antagonists, a lean design approach of replacing the bicyclic thienopyrimidine core with a monocyclic pyrrol-2-one chemotype was examined in the context of reducing aromatic ring count, while also contemplating enhanced flexibility as a means of decreasing flat character. The new compounds exhibited potent antagonism up to the sub-nanomolar range, thereby implying that the monocyclic ring could effectively serve as an effective bioisostere of the bicyclic system. The prototype compound 2m offered benefits like improved potency, reduced half-life, and enhanced solubility, while also demonstrating >5% reduction in weight gain in rats, thereby providing proof-of-concept for this new class of compounds as anti-obesity agents.

Identification of coumarin – benzimidazole hybrids as potential antibacterial agents: Synthesis, in vitro and in vivo biological assessment, and ADMET prediction

The direct-linked coumarin-benzimidazole hybrids, featuring aryl and n-butyl substituents at the N1-position of benzimidazole were synthesized through a Knoevenagel condensation reaction. This reaction involved the condensation of 1,2-diaminobenzene derivatives with coumarin-3-carboxylic acids in the presence of polyphosphoric acid (PPA) at 154 °C. The in vitro antibacterial potency of the hybrid molecules against different gram-positive and gram-negative bacterial strains led to the identification of the hybrids 6m and 6p with a MIC value of 6.25 μg/mL against a gram-negative bacterium, Klebsiella pneumonia ATCC 27736. Cell viability studies on THP-1 cells demonstrated that the compounds 6m and 6p were non-toxic at a concentration of 50 µM. Furthermore, in vivo efficacy studies using a murine neutropenic thigh infection model revealed that both compounds significantly reduced bacterial (Klebsiella pneumonia ATCC 27736) counts (more than 2 log) compared to the control group. Additionally, both compounds exhibited favorable physicochemical properties and drug-likeness characteristics. Consequently, these compounds hold promise as lead candidates for further development of effective antibacterial drugs.

Design, Synthesis, Characterization, and Cytotoxicity of New Pyrazolylmethylene-2-thioxoimidazolidin-4-one Derivatives towards Androgen-Sensitive LNCaP Prostate Cancer Cells.

A new class of pyrazolylmethylene-2-thioxoimidazolidin-4-one derivatives 3a-p were rationally designed and synthesized with the aim of exploring their potential as treatments for prostate cancer. The synthesized compounds 3a-p were biologically analyzed for their anticancer effects against AR+LNCaP, AR-PC-3, and Wi38 cell lines. The observed IC50 values against AR+LNCaP ranged between 10.27 ± 0.14 and 109.72 ± 2.06 µM after 24 h of incubation. Compounds 3i-k, 3m, and 3o-p recorded IC50 values of 05.22 ± 0.12 to 11.75 ± 0.07 µM after 48 h incubation in the presence of 1 nM DHT, with higher selectivity towards AR+LNCaP. Moreover, compounds 3i and 3k significantly induced Caspase 3 accumulation, reduced DNA content at the various stages of the cell cycle, and ultimately caused AR+LNCaP cell growth arrest, as confirmed by cell apoptosis assays. These findings suggest that these analogues of androgen receptor blockers have promising potential for further investigation as effective treatments for prostate cancer.

Identification of 5-Thiocyanatothiazol-2-amines Disrupting WDR5-MYC Protein-Protein Interactions.

MYC amplification is frequently observed in approximately 50% of human cancers, rendering it a highly desired anticancer target. Given the challenge of direct pharmacological inhibiting of MYC, impairing the interaction of MYC and its key cofactor WDR5 has been proposed as a promising strategy for MYC-driven cancer treatment. Herein, we report the discovery of 5-thiocyanatothiazol-2-amines that disrupt the WDR5-MYC interaction. Hit fragments were initially identified in a fluorescence polarization (FP)-based screening of an in-house library, and structural-activity relationship exploration resulted in the lead compounds 4m and 4o with potent inhibitory activities on WDR5-MYC interaction (K i = 2.4 μM for 4m; K i = 1.0 μM for 4o). These compounds were further validated via differential scanning fluorimetry (DSF) and coimmunoprecipitation (Co-IP). Moreover, 4m and 4o exhibited good cellular activities with the IC50 values at the micromolar level (IC50 = 0.71-7.40 μM) against multiple MYC-driven cancer cell lines. Our findings afforded a potential small molecule blocking the WDR5-MYC interaction.

UNVEILING THE POTENTIAL OF OXADIAZOLE TRIAZINE NUCLEOSIDE DERIVATIVE AS AN INHIBITOR OF SARS COV-2: A COMPUTATIONAL BREAKTHROUGH

SARS-CoV-2 created havoc worldwide in 2019 and was responsible for many deaths. No antiviral drugs have been developed to combat this virus. Oxadiazoles have multiple biological functions, such as anti-inflammatory, anti-tussive, anticancer, analgesic, cough suppressant, anti-oxidant, vasodilator, and more. Many drugs with oxadiazole nuclei have been repurposed to combat COVID-19. To identify a potent oxadiazole derivative against SARS-CoV-2, this article screened 45 substituted oxadiazole triazine nucleoside analogs to counter the three key targets of the SARS-CoV-2 life cycle: spike protein, main proteases, and RNA-dependent RNA-polymerase. The geometry of 45 substituted oxadiazole triazine nucleoside analogs was optimized by density functional theory (DFT) with the B3LYp method. Drug-likeness criteria, ADMET prediction, and docking were carried out for screening. Further analysis of ligand-protein interactions was performed by molecular dynamics simulation at 50 ns. Compounds 1a (-8.5 kcal) and 1m (-8.5 kcal) showed an excellent binding affinity with main proteases (6LU7) and -7.8Kcal, -7.6Kcal, respectively, for RdRp (6M71), while compound 1a and 1m exhibited -8.0 kcal, -8.2 kcal binding affinity respectively for spike protein (6LZG). The MD simulation of the protein-ligand complex with compounds 1a and 1m exhibited good compactness and stability, further validating the docking results. This study proposes these two compounds would be robust inhibitors of SARS CoV-2.

Discovery of Novel (+)-Nootkatone-Based Amine Derivatives as Potential Insecticide Candidates.

To discover novel natural product-based insecticides, a series of (+)-nootkatone-based amine derivatives 3a-t were prepared and evaluated for their insecticidal activities against Mythimna separata Walker, Myzus persicae Sulzer, and Plutella xylostella Linnaeus. Insecticidal assays showed that most of the title (+)-nootkatone derivatives exhibited stronger insecticidal activities against three insect pests than the precursor (+)-nootkatone after the introduction of amine groups on the parent (+)-nootkatone. Compounds 3a, 3d, 3h, 3m, 3n, 3p, and 3r displayed more promising growth inhibitory (GI) effect against M. separata than the commercially available botanical insecticide toosendanin. Compound 3o exhibited the most potent aphicidal activity with an LD50 value of 0.011 μg/larvae, which was 2.09-fold higher than the positive control rotenone. Additionally, compounds 3g and 3n showed more promising larvicidal activity against P. xylostella with LC50 values of 260 and 230 mg/L, respectively, superior to that of rotenone (460 mg/L). Moreover, derivatives 3g and 3n exhibited better control efficacy toward P. xylostella than rotenone under greenhouse conditions. Preliminary mechanistic studies revealed that derivative 3n could inhibit the activity of glutathione S-transferase (GST) in P. xylostella and thus exerted larvicidal activity, and molecular docking further demonstrated that 3n could interact well with some amino acid residues of GST. Finally, the toxicity assay suggested that derivatives 3g and 3n were relatively less toxic to nontarget organisms. These findings will provide insights into the development of (+)-nootkatone derivatives as green pesticides.

Quantum chemical modelling, molecular docking, synthesis and experimental anti-microbial activity of 1,4-diazepan linked piperidine derivative

BackgroundIn this work, we represent synthesis, in silico analysis and biological activity of 1,4 diazepine linked piperidine derivatives (6a–6o). All the derivatives were screened for their anti-microbial activity against gram-positive (Staphylococcus aureus, Bacillus Subtills, Bacillus megaterium) and gram-negative (Escherichia coli, Pseudonymous, Shigella sp.) bacteria. Compounds were synthesized from reaction of tert-butyl 1,4-diazepane-1-carboxylic, butyryl chloride and varied aromatic aldehyde, further characterized by 1H NMR and LCMS spectral techniques.ResultUsing ampicillin as a positive control, the synthetic compounds 6a–6o were tested for their in-silico study and experimental anti-microbial activity against gram-positive (Staphylococcus aureus, Bacillus Subtills, Bacillus megaterium) and gram-negative (Escherichia coli, Pseudonymous, Shigella sp.) bacteria. According to in vitro assay compound 6a, compound 6c, compound 6d, compound 6m and compound 6I showed higher activity against all the tested strains. Molecule 6i, compound 6j, compound 6k, compound 6f has good to moderate antibacterial activity. DFT computations were used to optimize the molecular geometry at the B3LYP/6-31G (d, p) theoretical level. The corresponding energy values of molecular orbitals were visualized using optimized geometries. Moreover, Auto Dock Vina 1.2.0 is used to assess molecular docking against two target proteins, Bacillus subtilis (PDB ID: 6UF6) and Protease Vulgaris (PDB ID: 5HXW). The target molecule 6b displayed the best binding energies for both. Additionally, we calculated the ADME for each molecule (6a–6o).ConclusionAll fifteen synthesized compounds were screened for their in vitro and in silico analysis. In vitro analysis for anti-microbial activity was carried out against gram-positive (Staphylococcus aureus, Bacillus Subtills, Bacillus megaterium) and gram-negative (Escherichia coli, Pseudonymous, Shigella sp.) bacteria and compound 6a, compound 6c, compound 6d, compound 6m and compound 6I exhibits more potent activity towards all tested strains. Molecular docking is performed against target proteins, L-amino acid deaminase from Proteus Vulgaris and LcpA ligase from Bacillus subtilis, representing the Gram-negative bacterium and Gram-positive bacterium, respectively. Compound 6b showed the highest no. of interaction with protein according to molecular docking. With the advent of innovative techniques like ADME, we select their hit compounds early on and anticipate future pharmacokinetic and pharmacodynamic benefits and drawbacks of these promising therapeutic candidates.Graphical abstract

Synthesis, in vitro α-glucosidase inhibitory potential and in silico study of 2‑chloro pyridine incorporated thiosemicarbazones

Diabetes is a devastating metabolic illness that affects people of all ages and is widespread around the world as a result of the malfunctioning of prior treatment approaches. This work attempts to treat type 2 diabetes mellitus (T2DM) by outlining the design, synthesis, in vitro and in silico assessment of 2-Nicotinaldehyde-based thiosemicarbazones as possible inhibitors of α-glucosidase. The synthesized derivatives 3(a-m) displayed excellent to good inhibitory potential against standard drug acarbose (IC50 = 4.10 ± 0.16 µM to 32.76 ± 0.80 µM. Among these compounds 3m displayed highest inhibition activity with IC50 value of 4.10 ± 0.16 µM. SAR of the derivatives have shown that the compounds with meta substitution displayed better activity than the para substitution. In order to obtain more profound understanding, molecular dynamics, and in silico molecular docking simulations were performed to examine the interactions, stability, orientation, and conformation of the synthesized derivatives inside the α-glucosidase active pocket.

Design, synthesis, and biological evaluation of pyrido[2,3-d]pyrimidin-7(8H)-one derivatives as potent USP1 inhibitors

USP1 has emerged as a novel and potential target for drug discovery in single therapeutic agents or combination with chemotherapy and molecular targeted therapy. In this study, based on the disclosed structure of ML323 and KSQ-4279, we designed and synthesized a series of pyrido[2,3-d]pyrimidin-7(8H)-one derivatives as potent USP1 inhibitors by cyclization strategy and the systematic structure−activity relationship exploration was conducted. The representative compounds 1k, 1m and 2d displayed excellent USP1/UAF inhibition and exhibited strong antiproliferation effect in NCI–H1299 cells. Further flow cytometry analysis revealed that they could arrest breast cancer cells MDA-MB-436 in the S phase. Inhibition mechanism study of compound 1m indicated these derivatives acted as reversible and noncompetitive USP1 inhibitors. Of note, the combination of compound 1m with PARP inhibitor olaparib generated enhanced cell killing in olaparib-resistant MDA-MB-436/OP cells, and compound 1m exhibited excellent oral pharmacokinetic properties in mice. Overall, our efforts may provide a reliable basis for the development of novel USP1 inhibitor as a single therapeutic agent and in combination with PARP inhibitors.

Synthesis of novel hybrids of 1,2,3-triazoles-hydrazone: targeting cholinesterases and Alzheimer's related genes.

Aim: A new series of 1,2,3-triazole-hydrazone derivatives were developed to evaluate their anti-Alzheimer's activity. Materials & methods: All compounds were screened toward cholinesterases via the modified Ellman's method. The toxicity assay on SH-SY5Y cells was performed using the MTT assay, and the expression levels of GSK-3α, GSK-3β, DYRK1 and CDK5 were assessed in the presence of compounds 6m and 6p.Results:6m and 6p; acting as mixed-type inhibitors, exhibited promising acetylcholinesterase and butyrylcholinesterase inhibitory activity, respectively. 6m demonstrated no toxicity under tested concentrations on the SH-SY5Y cells and positively impacted neurodegenerative pathways. Notably, 6m displayed a significant downregulation in mRNA levels of GSK-3α, GSK-3β and CDK5.Conclusion: The target compounds could be considered in developing anti-Alzheimer's diseaseagents.

Enzymatic synthesis of pyridine heterocyclic compounds and their thermal stability

An efficient method was discovered for catalyzing the esterification under air using Novozym 435 to obtain pyridine esters. The following conditions were found to be optimal: 60 mg of Novozyme 435, 5.0 mL of n-hexane, a molar ratio of 2:1 for nicotinic acids (0.4 mmol) to alcohols (0.2 mmol), 0.25 g of molecular sieve 3A, a revolution speed of 150 rpm, a reaction temperature of 50 °C, and reaction time of 48 h. Under nine cycles of Novozym 435, the 80 % yield was consistently obtained. Optimum conditions were used to synthesize 23 pyridine esters, including five novel compounds. Among them, gas chromatography-mass spectrometry-olfactometry (GC-MS-O) showed phenethyl nicotinate (3g), (E)-hex-4-en-1-yl nicotinate (3m), and octyl nicotinate (3n) possessed strong aromas. Thermogravimetric analysis (TG) revealed that the compounds 3g, 3m and 3n exhibited stability at the specified temperature. This finding provides theoretical support for adding pyridine esters fragrance to high-temperature processed food.

Next generation imidazothiazole and imidazooxazole derivatives as potential drugs against brain-eating amoebae.

Managing primary amoebic meningoencephalitis, induced by Naegleria fowleri poses a complex medical challenge. There is currently no specific anti-amoebic drug that has proven effectiveness against N. fowleri infection. Ongoing research endeavours are dedicated to uncovering innovative treatment strategies, including the utilization of drugs and immune modulators targeting Naegleria infection. In this study, we explored the potential of imidazo[2,1-b]thiazole and imidazooxazole derivatives that incorporate sulfonate and sulfamate groups as agents with anti-amoebic properties against N. fowleri. We assessed several synthesized compounds (1f, 1m, 1q, 1s,and 1t) for their efficacy in eliminating amoebae, their impact on cytotoxicity, and their influence on the damage caused to human cerebral microvascular endothelial (HBEC-5i) cells when exposed to the N. fowleri (ATCC 30174) strain. The outcomes revealed that, among the five compounds under examination, 1m, 1q, and 1t demonstrated notable anti-parasitic effects against N. fowleri (P ≤ 0.05). Compound 1t exhibited the highest anti-parasitic activity, reducing N. fowleri population by 80%. Additionally, three compounds, 1m, 1q, and 1t, significantly mitigated the damage inflicted on host cells by N. fowleri. However, the results of cytotoxicity analysis indicated that while 1m and 1q had minimal cytotoxic effects on endothelial cells, compound 1t caused moderate cytotoxicity (34%). Consequently, we conclude that imidazo[2,1-b]thiazole and imidazooxazole derivatives containing sulfonate and sulfamate groups exhibit a marked capacity to eliminate amoebae viability while causing limited toxicity to human cells. In aggregate, these findings hold promise that could potentially evolve into novel therapeutic options for treating N. fowleri infection.

Discovery of novel piperidine-containing thymol derivatives as potent antifungal agents for crop protection.

Plant fungal diseases pose a significant threat to crop production. The extensive use of chemical pesticides has led to growing environmental safety risks and pesticide resistance of various plant pathogens. Therefore, it is an urgent task to explore novel eco-friendly fungicidal agents with high efficacy to combat fungal infection. In this study, we rationally designed a series of novel thymol derivatives by incorporation of the sulfonamide moiety and evaluated their biological activities against plant pathogenic fungi. The bioassay results underscored the remarkable in vitro antifungal activity of compounds 5m and 5t against Phytophthora capsici (P. capsici), with EC50 values of 8.420 and 8.414 μg/mL, respectively. Their efficacies were superior to that of widely used commercial fungicides azoxystrobin (AZO, 20.649 μg/mL) and cabendazim (CAB, 251.625 μg/mL). Furthermore, compound 5v exhibited excellent in vitro antifungal activity against Sclerotinia sclerotiorum (S. sclerotiorum), with an EC50 value of 12.829 μg/mL, significantly outperforming AZO (63.629 μg/mL). In vivo bioassays demonstrated the impactful activity of compound 5v against S. sclerotiorum, achieving over 98% curative and protective efficacies at the concentration of 200 μg/mL. Further mechanistic investigations unveiled that compound 5v induced mycelial shrinkage and collapse in S. sclerotiorum, resulting in organelle damage and the accumulation of antioxidant enzyme activity. The significant antifungal efficacy of the prepared thymol derivatives shall encourage further exploration of compound 5v as a promising candidate to develop novel fungicides for crop protection. © 2024 Society of Chemical Industry.

Novel Pyrido[4,3-d]pyrimidine Derivatives as Potential Sterol 14α-Demethylase Inhibitors: Design, Synthesis, Inhibitory Activity, and Molecular Modeling.

Thirty-four new pyrido[4,3-d]pyrimidine analogs were designed, synthesized, and characterized. The crystal structures for compounds 2c and 4f were measured by means of X-ray diffraction of single crystals. The bioassay results showed that most target compounds exhibited good fungicidal activities against Pyricularia oryzae, Rhizoctonia cerealis, Sclerotinia sclerotiorum, Botrytis cinerea, and Penicillium italicum at 16 μg/mL. Compounds 2l, 2m, 4f, and 4g possessed better fungicidal activities than the commercial fungicide epoxiconazole against B. cinerea. Their half maximal effective concentration (EC50) values were 0.191, 0.487, 0.369, 0.586, and 0.670 μg/mL, respectively. Furthermore, the inhibitory activities of the bioactive compounds were determined against sterol 14α-demethylase (CYP51). The results displayed that they had prominent activities. Compounds 2l, 2m, 4f, and 4g also showed better inhibitory activities than epoxiconazole against CYP51. Their half maximal inhibitory concentration (IC50) values were 0.219, 0.602, 0.422, 0.726, and 0.802 μg/mL, respectively. The results of molecular dynamics (MD) simulations exhibited that compounds 2l and 4f possessed a stronger affinity to CYP51 than epoxiconazole.

Synthesis and anti-HCV activity of novel 5-arylmethylene-1,3-thiazolidin-4-one derivatives via suppression of NS5B polymerase and COX-2

Hepatitis C (HCV) is a viral infection that leads to forms of acute and chronic liver disease, including cirrhosis (scarring of the liver) and liver cancer. The World Health Organization (WHO) estimated in 2019 that approximately 290,000 people died from hepatitis C (mostly from cirrhosis and hepatocellular carcinoma). Direct-acting antiviral drugs (DAAs) can cure more than 95% of individuals with hepatitis C infection, while research on the discovery of new antiviral agents is still ongoing. The Hepatitis C virus (HCV) can cause various biochemical changes in liver cells, and some of these changes are associated with the COX-2 enzyme. The identification of its role in promoting growth in liver cells as well as its involvement in various cancer types, including hepatocellular carcinoma, has made COX-2 an important target in the development of new agents effective against HCV. In this study, thirty-six new 5-arylmethylene-2-imino-1,3-thiazolidin-4-one derivatives (5a-s, 6a-s) were synthesized through Knoevenagel condensation of 2-[(4-substitutedpyridin-2-yl)imino]-1,3-thiazolidin-4-one derivatives with various aldehydes. Structures of the synthesized compounds were elucidated by the use of spectral and chromatographic techniques, besides elemental analyses. Four compounds were selected for further studies as they were found to suppress the NS5B protein with anti-HCV activity using the Western Blotting method. The selected compounds 5o, 6m, 6r, and 6s inhibited HCV with EC50 values of 8.0 ± 0.2 µM, 13.9 ± 0.45, 9.2 ± 0.2 µM, and 12.1 ± 0.1 µM, respectively. It was determined that these compounds reduced HCV-induced COX-2 promoter activity in Ava5 cells compared to Huh7 cells. The antiviral effects of the compounds were also investigated on DENV, closely related to HCV due to sharing certain biological, structural, and mechanical properties throughout their life cycles. However, no significant effect was observed in the preliminary screening study, indicating the compounds' specificity for HCV. Considering the relationship between HCV, DENV, and COX-2, the compounds' COX-1 and COX-2 enzyme inhibition potentials were investigated both in vitro and in silico. Compounds 6d, 6e, 6f, and 6m, which exhibited high selective COX-2 inhibition, were discussed for their interactions with the active site. Our study revealed that our target compounds suppressed COX-2 both at the protein level and through enzyme inhibition, thus providing promising findings for the discovery of new anti-HCV effective COX-2 inhibitors.

Insight on novel oxindole conjugates adopting different anti-inflammatory investigations and quantitative evaluation.

Background: A dual COX/5-LOX strategy was adopted to develop new oxindole derivatives with superior anti-inflammatory activity. Methods: Three series of oxindoles - esters 4a-p, 6a-l and imines 7a-o - were synthesized and evaluated for their anti-inflammatory and analgesic activities. Molecular docking and predicted pharmacokinetic parameters were done for the most active compounds. A new LC-MS/MS method was developed and validated for the quantification of 4h in rat plasma. Results: Compounds 4h, 6d, 6f, 6j and 7m revealed % edema inhibition up to 100.00%; also, 4l and 7j showed 100.00% writhing protection. Compound 4h showed dual inhibitory activity with IC50=0.0533 and 0.4195μM for COX-2 and 5-LOX, respectively. Molecular docking rationalized the obtained biological activity. The pharmacokinetic parameters of 4h from rat plasma were obtained.

Discovery of new 2-(3-(naphthalen-2-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazole derivatives with potential analgesic and anti-inflammatory activities: In vitro, in vivo and in silico investigations

Joining the global demand for the discovery of potent NSAIDs with minimized ulcerogenic effect, new pyrazole clubbed thiazole derivatives 5a-o were designed and synthesized. The new derivatives were initially evaluated for their analgesic activity. Eight compounds 5a, 5c, 5d, 5e, 5f, 5h, 5m, and 5o showed higher activity than Indomethacin (potency = 105–130 % vs. 100 %). Subsequently, they were picked for further evaluation of their anti-inflammatory activity, ulcerogenic liability as well as toxicological studies. Derivatives 5h and 5m showed a potential % edema inhibition after 3 h (79.39 % and 72.12 %, respectively), with a promising safety profile and low ulcer indices (3.80 and 3.20, respectively). The two compounds 5h and 5m were subjected to in vitro COX-1 and COX-2 inhibition assay. The candidate 5h showed nearly equipotent COX-1 inhibition (IC50 = 38.76 nM) compared to the non-selective reference drug Indomethacin (IC50 = 35.72 nM). Compound 5m expressed significant inhibitory activities and a higher COX-2 selectivity index (IC50 = 87.74 nM, SI = 2.05) in comparison with Indomethacin (SI = 0.52), with less selectivity than Celecoxib (SI = 8.31). Simulation docking studies were carried out to gain insights into the binding interaction of compounds 5h and 5m in the vicinity of COX-1 and COX-2 enzymes that illustrated the importance of pyrazole clubbed thiazole core in hydrogen bonding interactions. The thiazole motif of compounds 5h and 5m exhibited a well orientation toward COX-1 Arg120 key residue by hydrogen bonding interactions. Compound 5h revealed an additional arene-cation interaction with Arg120 that could rationalize its superior COX-1 inhibitory activity. Compounds 5h and 5m overlaid the co-crystallized ligand Celecoxib I differently in the active site of COX-2. Compound 5m showed an enhanced accommodation with binding energy of − 6.13 vs. − 1.70 kcal/mol of compounds 5h. The naphthalene ring of compound 5m adopted the Celecoxib I benzene sulfonamide region that is stabilized by hydrogen-arene interactions with the hydrophobic sidechains of the key residues Ser339 and Phe504. Further, the core structure of compound 5m, pyrazole clubbed thiazole, revealed deeper hydrophobic interactions with Ala513, Leu517 and Val509 residues. Finally, a sensitive and accurate UPLC-MS/MS method was developed for the simultaneous estimation of some selected promising pyrazole derivatives in rat plasma. Accordingly, compounds 5h and 5m were suggested to be promising potent analgesic and anti-inflammatory agents with improved safety profiles and a novel COX isozyme modulation activity.

Molecular Docking, Toxicity Study and Antimicrobial Assessment of Novel Synthesized 1,3-(Disubstituted)-thiazol-2-amines

In current study, a novel analogous of substituted-2-aminothiazoles (3a-o) were synthesized through a multi-step synthetic process. Structural elucidation of these newly synthesized substituted-2-aminothiazoles were achieved using combination of analytical techniques, comprising proton nuclear magnetic resonance (PNMR), mass spectrometry and FTIR. An in vitro investigation was performed to measure the efficacy of antibacterial and antimycotic characteristics of these novel compounds (3a-o). Specifically, the growth-inhibiting action against the test fungal strains, including A. niger, M. purpureos and A. flavus was examined. Additionally, their inhibitory antibacterial activity against key bacterial strains, including P. aeruginosa, S. aureus and E. coli was ascertained employing the agar diffusion technique. The results of antibacterial screening disclosed that maximum number of the thiazole derivatives viz. 3a, 3d, 3e, 3i, 3k, 3l and 3n displayed minimum inhibitory concentration of 12.5 µg/mL for E. coli. While compounds 3k and 3n displayed minimum inhibitory concentration of 12.5 µg/mL for S. aureus. A minimum inhibitory concentration of 25 µg/mL was exhibited by compounds 3i, 3l and 3n against P. aeruginosa. None of the 2-aminothiazole derivative disclosed promising action against the fungal strains. Screening for in silico ADME and toxicity studies revealed that compounds are fairly compatible and were devoid of potential toxicity except compounds 3j and 3m. The docking studies on DNA gyrase (PDB ID; 1KZN) shows favourable binding interaction comparable to the pre-occupied ligand clorobiocin.

Hydroxamate-Containing Bisphosphonates as Fosmidomycin Analogues: Design, Synthesis, and Proherbicide Activity.

Fosmidomycin (FOS) is a natural product inhibiting the DXR enzyme in the MEP pathway and has stimulated interest for finding more suitable FOS analogues. Herein, two series of FOS analogue hydroxamate-containing bisphosphonates as proherbicides were designed, with bisphosphonate replacing the phosphonic unit in FOS while retaining the hydroxamate (BPF series) or replacing it with retro-hydroxamate (BPRF series). The BPF series were synthesized through a three-step reaction sequence including Michael addition of vinylidenebisphosphonate, N-acylation, and deprotection, and the BPRF series were synthesized with a retro-Claisen condensation incorporated into the reaction sequence. Evaluation on model plants demonstrated several compounds having considerable herbicidal activities, and in particular, compound 8m exhibited multifold activity enhancement as compared to the control FOS. The proherbicide properties were comparatively validated. Furthermore, DXR enzyme assay, dimethylallyl pyrophosphate rescue, and molecular docking verified 8m to be a promising proherbicide candidate targeting the DXR enzyme. In addition, 8m also displayed good antimalarial activities.

Antioxidant and antibacterial activities of 5-mercapto(substitutedthio)-4-substituted-1,2,4-triazol based on nalidixic acid: A comprehensive study on its synthesis, characterization, and In silico evaluation

This study introduces a series of novel Alkyl thio-1,2,4-triazole (4a-p) and mercapto-1,2,4-triazole (3a-d) compounds derived from nalidixic acid. The synthesis was streamlined, involving interactions between nalidixic acid hydrazide and various isothiocyanates to yield cyclic and alkyl(aryl) sulfide compounds, characterized using 1H NMR, 13C NMR, IR, and elemental analysis. Antioxidant capabilities were quantified through DPPH and ABTS assays, highlighting significant potential, especially for compound 3d, which demonstrated an ABTS IC50 value of 0.397 μM, on par with ascorbic acid (IC50 = 0.87 μM). Antibacterial efficacy was established through MIC assessments against a broad spectrum of Gram-positive and Gram-negative bacteria, including Candida albicans. Compounds 3b, 4e, 4h, 4j, 4i, 4m, and 4o showed broad-spectrum activity, with 4k and 4m exhibiting pronounced potency against E. coli. Molecular docking studies validated the antibacterial potential, with compounds 4f and 4h showing high binding affinities (docking scores of −9.8 and −9.6 kcal/mol, respectively), indicating robust interactions with the bacterial enzyme targets. These scores underscore the compounds' mechanistic basis for their antibacterial action and support their therapeutic promise. Furthermore, compounds 3b, 4i, and 4m, identified through drug-likeness and toxicity predictions, were highlighted for their favorable profiles, suggesting their suitability for oral antibiotic therapies. This comprehensive study, blending synthetic, in vitro, and in silico approaches, emphasizes the triazole derivatives' potential as future candidates for antibiotic and antioxidant applications, particularly spotlighting compounds 3b, 4i, and 4m due to their promising efficacy and safety profiles.