Compounds 4i Research Articles

New thiazolidin-4-ones as anti-cervical cancer agents targeting EGFR: design, synthesis, and computational studies.

A new series of 3,4-dihydronaphthalen-1(2 h)-ylidene)hydrazineylidene)-5-substituted thiazolidin-4-one derivatives were designed and synthesized. The new compounds were screened for in vitro antitumor activity against Hela cancer cell line. The compounds 7b, 7 h, and 7i produced more potent cytotoxicity than doxorubicin with IC50 values of 1.83 ± 0.1, 2.54 ± 0.14, 2.75 ± 0.15, and 3.63 ± 0.2 μM, respectively. They also showed a promising safety profile against WI-38 normal cells. In addition, compound 7b produced a promising multi-kinase inhibition against EGFR (WT) while being very selective toward the mutant forms (L858R and T790M) with IC50 values of 0.099 ± 0.006, 0.064 ± 0.006, and 0.026 ± 0.007 μM, respectively, in comparison to gefitinib and osimertinib. A study of the cell cycle in Hela cells showed that 7b arrests cell cycle in the pre-G1 phase and causes early and late apoptosis. Eventually, the molecular docking results showed that 7b had good-binding interactions with EGFRWT, EGFRL858R, and EGFRT790M. Compound 7b was predicted to have promising oral absorption, good drug-likeness, and low toxicity risks in humans. Moreover, MD simulations confirmed the stable complexes of 7b with EGFRWT, EGFRL858R, and EGFRT790M (with RMSD 0.12-0.35 nm, RMSF 0.2-0.55 nm, SASA 140-150, and Rg 1.80-2.00 nm).

Synthesis and in vitro/in silico evaluation of the antimalarial activity of potential amino-quinoline derivatives

In this study, a series of N-arylamino-7-chloroquinolines were synthesized via an alkylation reaction involving aniline derivatives (2) and 4,7-dichloroquinoline (1). Additionally, the synthesis of a library of N-aryl-N-benzylamino-7-chloroquinoline analogues, modified on the aniline nitrogen, has also reported. A structure-activity relationship (SAR) study was conducted to evaluate the biological efficacy and safety of these derivatives against chloroquine-sensitive (Pf3D7) and chloroquine-resistant (PfW2) Plasmodium falciparum strains. Compounds 5i and 5c showed promising efficacy against the Pf3D7 strain with IC50 values of 0.25 μM and 0.54 μM, respectively, while compound 5l demonstrated significant activity against the PfW2 strain with an IC50 of 5.82 μM. The cytotoxicity of these compounds was also evaluated on HUVEC cell lines. Additionally, their pharmacological and pharmacokinetic (ADME) properties were studied to predict their fate and identify promising candidates for further clinical studies.

1,3-Naphthoxazine derivatives: Synthesis, in silico pharmacokinetic studies, antioxidant and photoprotective properties

Investigation into the interactions between photoprotective agents and skin can offer a precise understanding of their biological behaviors in vitro and in vivo, providing crucial insights for generating new substances. For this purpose, we designed and synthesized a series of naphthoxazine derivatives and examined their photoprotective properties. 1,3-naphthoxazine derivatives were synthesized through the multi-component reaction of 2-naphthol, arylamines and aromatic aldehydes in the presence of copper(II) trifluoromethanesulfonate (Cu(OTf)2) and (±)-Camphor-10-sulfonic acid ((±)-CSA) catalyst system under sonication. The potential of these synthesized 1,3-naphthoxazine derivatives as antioxidants and viable organic structural-based sunscreen ingredients has been investigated. Sun protection factor (SPF) assay results showed that especially compounds 4i, 4c, 4k, 4d, 4r, and 4h had remarkably high activity (23.65, 23.57, 23.04, 21.94, 20.80, and 20.26, respectively at 900 µg/mL concentration). Additionally, antioxidant activity of the synthesized compounds was evaluated and compounds 4h, 4e, 4b, and 4j exhibited the highest activities in DPPH scavenging activity assay (86.46 %, 82.83 %, 80.78 %, and 80.65 % respectively at 400 µg/mL concentration). The synthesized compounds exhibit promising characteristics for effective UV radiation absorption, suggesting their suitability for inclusion in sunscreen formulations. Cytotoxic activity of compound 4k against normal human fibroblast cell line (MRC-5) was determined by CVDK-8 method. The results revealed that the compound provided remarkable viability (87.55 %) of MRC-5 cells at concentration of 100 µM. The study explores their efficacy in providing broad-spectrum protection against UVA and UVB rays, degradation and photostability, ADMET profile, and other pharmacokinetic properties.

Unprecedented synthesis of indole-linked tetra-substituted alkenes by catalyst-free domino reaction

Herein, we report a simple, efficient catalyst-free green domino reaction of indole, arylglyoxal, and cyclic 1,3-dicarbonyls such as barbituric acid derivatives/dimedone at 100oC in dimethylformamide medium in open air condition. In this reaction, one C-C and one C=C bonds have been formed in one-pot without using any additive or metal based reagent. Considering the presence of indole, benzoyl and cyclic 1,3-dicarbonyl moieties in the products, it is expected that they will exhibit interesting medicinal properties. All the synthesized products were characterized by recording FTIR, 1H NMR, 13C NMR, and HRMS. Moreover, a single crystal XRD of compound 4i was recorded to confirm the structure of the product. Operational simplicity, gram-scale synthesis, mild reaction conditions, good yields, and wide substrate scope are the salient features of this methodology.

New 4-methanesulfonyloxy benzohydrazide derivatives as potential antioxidant and carbonic anhydrase I and II inhibitors: synthesis, characterization, molecular docking, dynamics & ADME studies

As an archetypal molecule, hydrazides have a crucial vital role in numerous applications, so hydrazide-related inhibitors, especially sulfur-enriched, are favored. In the present work, we designed, synthesized and characterized fifteen novel benzohydrazide derivatives containing 4-methanesulfonyloxy and arylidene building blocks with a four-step synthesis pathway. The inhibitory potential of the compounds was assessed using human carbonic anhydrases I and II (hCA I and II) isozymes and the results were compared to those of the standard inhibitor, acetazolamide (AZA). The antioxidant activity profiles for all compounds were also examined using various bioanalytical methods and the results were compared with the standards. The hCA I and II were the best inhibited by compounds 5f, 5g, and 5i with inhibition constants IC50 in the range 20.45–51.43 nM (AZA: IC50=218.38) for hCA I and 33.54–42.45 nM (AZA: IC50=44.39) for hCA II. Structure-activity relationships were also discussed and discovered that hCA I and II inhibition was unaffected by the presence of an electron-withdrawing or releasing group. This effectiveness was the only result of the sort of substituted group(s), which was located at the reagent. Molecular docking and dynamics simulations showed that compounds 5f, 5g, and 5i have strong and stable interactions with key amino acids and zinc ions in the active sites of enzymes, which supports their ability to block enzyme activity. In silico ADME studies predicted favorable drug-like properties and high human oral absorption for all synthesized compounds. In silico ADME studies predicted favorable drug-like properties and high human oral absorption for all synthesized compounds. These findings highlight the multifunctional potential of the synthesized benzohydrazide derivatives as hCA I and II inhibitors and antioxidants, paving the way for their further development and optimization for therapeutic applications.

Synthesis and Structure–Activity Relationship of Thiourea Derivatives Against Leishmania amazonensis

Background: Leishmaniasis, caused by Leishmania protozoa and transmitted by vectors, presents varied clinical manifestations based on parasite species and host immunity. The lack of effective vaccines or treatments has prompted research into new therapies, including thiourea derivatives, which have demonstrated antiprotozoal activities. Methods: We synthesized two series of N,N′-disubstituted thiourea derivatives through the reaction of isothiocyanates with amines. These compounds were evaluated in vitro against promastigote and amastigote forms of L. amazonensis, alongside cytotoxicity assessments on macrophages. In silico studies were conducted to analyze structure–activity relationships (SARs) and drug-likeness. Results: A total of fifty thiourea derivatives were synthesized and tested. Compound 3e from the first generation exhibited significant anti-leishmanial activity with an IC50 of 4.9 ± 1.2 µM and over 80-fold selectivity compared to that of miltefosine (IC50 = 7.5 ± 1.2 µM). The introduction of a piperazine ring in the second-generation thioureas enhanced potency and selectivity, with compound 5i achieving an IC50 of 1.8 ± 0.5 µM and a selectivity index of approximately 70. Pharmacokinetic predictions indicated favorable profiles for the active compounds. Conclusions: SAR and ADMET analyses identified compound 5i as the most promising candidate for further preclinical evaluation, suggesting that piperazine thiourea derivatives represent a novel class of anti-leishmanial agents.

Discovery of Janus Kinase and Histone Deacetylase Dual Inhibitors as a New Strategy to Treat Psoriasis.

Psoriasis is a common, chronic, recurrent, and inflammatory skin disease, which causes physical and psychological problems in patients and lacks effective and economic therapeutics. Herein, we designed Janus kinase (JAK) and histone deacetylase (HDAC) dual inhibitors as a new strategy for the treatment of psoriasis. In particular, compound 11i was identified with excellent inhibitory activity toward JAKs (JAK2 IC50 = 0.49 nM) and HDACs (HDAC6 IC50 = 12 nM). Moreover, it exhibited potent activities in inhibiting the proliferation of TNF-α-induced HaCAT cells and the production of nitric oxide. Importantly, compound 11i significantly ameliorated psoriasis-like skin lesions in an imiquimod-induced murine model with low toxicity, which was superior to JAK inhibitor momelotinib, HDAC inhibitor vorinostat, and their combination. This work provided a proof-of-concept for JAK/HDAC dual inhibitors as a promising strategy for the treatment of psoriasis.

Natural Products-Based Anticancer Agents: Synthesis and Anticancer Activities of Funtumine Amide/Sulfonamide Derivatives.

Funtumine is a pregnene-type steroidal alkaloid exhibiting moderate anticancer activity. To discover novel natural product-based anticancer drugs, a series of novel funtumine amide/sulfonamide derivatives were papered and identified using spectroscopic techniques. Additionally, the structures of compounds 2j, 3a, and 4k were further confirmed through X-ray diffraction analysis. Biological activity experiments conducted against three cancer cell lines revealed that several of the synthesized compounds demonstrated inhibition activities comparable to or exceeding those of the commercial anticancer agent, 5-Fluorouracil. Especially compound 4i demonstrated a notably strong growth inhibitory effect on HePG2 (IC50=14.89 μM) and HCT116 (IC50=15.67 μM) cell lines, while exhibiting minimal cytotoxicity towards human normal BEAS-2B cells. Preliminary structure-activity relationships (SARs) analysis indicated that the conversion of the carbonyl group at the C-20 position of funtumine to a hydroxyl group could yield more potent compounds.

Molecular docking, ADME properties and synthesis of thiophene sulfonamide derivatives

This study investigates the drug-like properties of target molecules containing thiophene sulfonamide groups (7a–7s) using computational molecular docking techniques. The binding interactions of these derivatives were assessed using protein 2NSD (Enoyl acyl carrier protein reductase InhA, complexed with N-(4-methylbenzoyl)-4-benzylpiperidine, PDB DOI: 10.2210/pdb2NSD/pdb) as the receptor. Molecular docking results revealed notable docking scores for all compounds, ranging from −6 to −12 kcal/mol. Compounds 7e, 7i, and 7f, in particular, demonstrated impressive glide scores (>11 kcal/mol) and were selected for further analysis through molecular dynamics simulations, which provided deeper insights into their dynamic behavior and stability. The drug-like properties of these molecules were evaluated based on Lipinski’s Rule of Five and ADME (Absorption, Distribution, Metabolism, and Excretion) criteria and compared with known drugs. Additionally, we synthesized these target molecules (7a–7s) using Suzuki-Miyaura coupling with a nickel catalyst replacing palladium. The chemical structures of the synthesized compounds were confirmed through elemental analysis, LC-MS,1H-NMR, and 13C-NMR spectroscopy.

Synthesis of Paracetamol‐Appended Bis 1,2,3‐Triazole Analogues as Anti‐Inflammatory Agents

AbstractParacetamol‐based bis 1,2,3‐triazole analogues were synthesized involving copper‐catalyzed click chemistry protocol. The new compounds were characterized by 1H NMR, 13C NMR, and mass spectral techniques. All the compounds were evaluated for their in vitro anti‐inflammatory properties using diclofenac as standard reference. The compound 6b with chlorine and fluorine functions displayed outstanding activity with IC50 values of 7.34 ± 0.45 µM and 7.84 ± 0.47 µM, respectively. Compound 6g with methyl and fluorine functions displayed best activity with IC50 values of 9.34 ± 0.22 µM and 9.40 ± 0.35 µM, respectively. Compound 6i, 6k, 6f, 6a, 6e, 6h, 6j, and 6l exhibited promising activity with respect to diclofenac. Using PyRx tool, the molecular docking study against crystal structure of COX‐2 proved the binding efficacies with notable binding interactions.

Facile synthesis of substituted 2-styrylnaphthyridine derivatives via sp3 C-H functionalization under mild conditions and their antimicrobial activity and Electrochemical properties

Metal-free synthetic approach for the Efficient synthesis of pyrazole, imidazopyridine based substituted 2-styryl-1, 8-naphthyridines has developed via sp3 CH activation of substituted 7-methyl-1,8-naphthyridines, with various aromatic/heteroaromatic aldehydes through knoevenagel condensation under mild basic (Piperidine) conditions. Further, the synthesized titled molecules tested their absorption and emission spectra, interestingly compound 3d was found to be that inspiring emission spectra at 626 nm (red shift) with impressive stokes shift 133 nm. Moreover, some of the best resultant conjugate scaffolds (compounds 3c, 3d, 3e, and 4e) were analysed their electrochemical properties, thus, 3c, 3d, 3e, and 4e molecules respectively displaying medium to good redox potentials (compound 3e displays 0.3, -1.71 V respectively) and tested scanning rate (from 50 to 500 mV s−1) also. Furtherly, all synthsized derivatives analysed their biological activity, i.e., antifungal and antifungal. Among that, the compounds 3c, 3d, 3e, 3i, 3k, 3l, 5c, 5d and 5f respectively were established excellent inhibition zone of activity against standard drugs.

Design, Synthesis, and Screening for Anticancer and Antimicrobial Activities of New Dihydropyridine‐Anchored Pyrazole and 1,2,3‐Triazole Hybrids

AbstractTwo new libraries of diethyl and dimethyl dihydropyridines‐based pyrazole and 1,2,3‐triazole hybrids (7a–g and 7h–n) were synthesized via a series of reactions involving click chemistry, pyrazole synthesis, and multicomponent reaction. All the new compounds were screened for their in vitro anticancer activity and antimicrobial activities. The 4‐chloro substituted analogue (7i) in dimethyl ester series showed an excellent activity against all three, namely, human breast adenocarcinoma (MCF‐7), human cervical cancer (HeLa), and human breast cancer triple‐positive (BT‐474) cell lines with IC50 values of 0.119 ± 0.58 µM, 0.135 ± 0.13 µM, and 0.163 ± 0.31 µM, respectively compared to abemaciclib. Molecular docking studies performed on the best active compound 7i against crystal structure of CDK6 revealed its best binding score and interactions. Additionally, these libraries were screened for their antimicrobial activities and determined their MIC. Compounds with ─Cl (7b), ─OMe (7d), ─Me (7a) substitution, and without substitution (7e) significantly showed better MIC values in comparison to ampicillin and nystatin.

Anti colorectal cancer activity and in silico studies of novel pyridine nortopsentin analog as cyclin dependent kinase 6 inhibitor

Nortopsentins are a vital class of deep-sea sponge metabolites which can be used as leads for antitumor agents. Although their action has been studied in several diseases’ contexts, their cytotoxic activity against colorectal carcinoma has not yet been fully investigated. Therefore, a series of 2,6-bis(1H-indol-3-yl)-4-(substituted-phenyl)pyridin-5-carbonitriles 4a–j (nortopsentin analogs) was investigated for their cytotoxic activity against colorectal carcinoma. The analog 4i showed the highest antitumor activity via inducing cell cycle arrest at G1 phase. Cell cycle arrest was induced due to expression downregulation of CDK2, CDK4, and CDK6. In addition, 4i suppressed the enzymatic activity of CDK6. The theoretical study of some basic quantum factors and the geometric shape of compound 4i proved that the compound is stable and a soft molecule, in which the EHOMO and ELUMO energies were negative and had a small ∆E gap. 4i also demonstrated a high potential for oral bioavailability due to its adherence to Lipinski’s rule of five. The molecular docking studies of 4i analog showed good binding mode with CDK6 active pocket through the formation of multiple interactions with its key amino acids.

Microwave expedited Cu(I) catalyzed regioselective 1,2,3-triazoles as Mycobacterium Tuberculosis H37Rv inhibitors, in vitro α-amylase and α-glucosidase inhibition, in silico studies

In the present study, an efficient and convenient synthesis of novel 1,2,3-triazoles (8i-t) incorporated quinoline and coumarin cores has been reported. Microwave-assisted Huisgen 1,3-dipolar cycloaddition reaction of azide and alkyne resulted in high yields (88–94 %) of the title compounds. Regioselective single-product formation both under conventional and microwave methods is the foremost supremacy of this work. All the molecules were subjected to in vitro antibacterial assessment wherein the compounds 8i, 8k, 8l, 8n, and 8r demonstrated very good antibacterial activity against other bacterial strains tested. Compounds 8i, 8k, 8l, 8n, 8o, 8q, and 8r demonstrated excellent antitubercular activity with MICs in the range 1.60–6.25 µg/mL in comparison to the standard drugs (Isoniazid-1.60 µg/mL, Ciprofloxacin-3.25 µg/mL, Pyrazinamide-6.25 µg/mL). Compounds 8i, 8n, and 8r also exhibited inhibitory effects against α-amylase and α-glucosidase and thus, also showed anti-diabetic activity. The significantly active compounds were subjected to molecular docking and molecular dynamics simulation studies to study the putative binding pattern as well as the stability of the docked complexes, respectively. In silico ADME profiles of the titled compounds were also predicted to access the drug-likeness properties of the designed compounds. Titled compounds showed potential effectiveness as antibacterial and antidiabetic agents.

Multi-functional tyrosinase inhibitors derived from kojic acid and hydroquinone-like diphenols for treatment of hyperpigmentation: Synthesis and in vitro biological evaluation.

A series of multi-functional tyrosinase inhibitors derived from kojic acid (KA) and hydroquinone-like diphenols were designed and synthesized using click chemistry. The in vitro enzymatic assay revealed that all compounds containing a free enolic structure showed excellent activity against tyrosinase (IC50 = 0.14-3.7 µM), being significantly more potent than KA. The most active compounds were catechol (6c) and α-naphthol (6i) analogs with 138- and 96-fold higher potency than KA. On the other hand, all free phenolic compounds (6a-c and 6g-j) derived from aromatic diols showed outstanding free radical scavenging activities superior to KA. Certainly, the α-naphthol derivative 6i with IC50 = 10.1 µM was the most active anti-oxidant, being as potent as quercetin. The SAR analysis indicated that the enolic head of the conjugate molecules mainly contributes to the anti-tyrosinase activity, and the free phenolic part of the molecules can offer anti-oxidant potency. The anti-melanogenic assay of the most promising derivative, 6i, against melanoma (B16F10) cells demonstrated that the prototype compound 6i can significantly reduce the melanin content, more effectively than KA. By using a conjugation strategy, we have improved the tyrosinase inhibitory and radical scavenging activity in the multi-functional agents such as 6i over the parent compound KA, being potentially useful in the treatment of hyperpigmentation and other skin disorders.

Semi-Preparation and X-ray Single-Crystal Structures of Sophocarpine-Based Isoxazoline Derivatives and Their Pesticidal Effects and Toxicology Study.

Recently, research and development of novel pesticides from natural plant products have received much attention. To accelerate the application of sophocarpine as the agrochemical candidate, a series of novel sophocarpine-based isoxazoline derivatives were prepared by the 1,3-dipolar [2 + 3] cycloaddition reaction of sophocarpine with different chloroximes. Their structures were well characterized by high-resolution mass spectra, infrared spectra, and proton/carbon-13 nuclear magnetic resonance spectra. Eight steric configurations of compounds 5a, 5e', 5f, 5g, 5h, 5i, 5r, and 5u' were further determined by X-ray single-crystallography. Against Aphis citricola Van der Goot, compounds 5n (LD50: 0.032 μg/nymph) and 5o (LD50: 0.024 μg/nymph) exhibited greater than 3.7- and 4.9-fold potent aphicidal activity compared to sophocarpine (LD50: 0.118 μg/nymph). Against Tetranychus cinnabarinus Boisduval, derivative 5g displayed the most promising acaricidal activity with the LC50 value of 0.247 mg/mL, which was 14.2-fold that of sophocarpine. Compounds 5d and 5g also exhibited good control efficacy against T. cinnabarinus. Scanning electron microscopy images indicated that compound 5g can destroy the mite cuticle layer. These results will provide the foundation for the structural modification and use of sophocarpine derivatives as agrochemicals in the future.

Rationale design and synthesis of new roflumilast analogues as preferential selective and potent PDE-4B inhibitors

In this study, we designed and synthesized novel analogues of roflumilast that exhibit selective inhibition of PDE-4B. To accomplish this target; synthesis of novel series (4a-u, 5a-i, and 6) was done, aiming at obtaining new PDE-4B inhibitors hits based on the proposed pharmacophore, 1-(cyclopropylmethoxy)-2-(difluoromethoxy) benzene moiety. Enzyme assay was used to measure the IC50 values for the PDE-4B inhibition of all the synthesized compounds along with roflumilast as a reference drug. The results demonstrated that most of the examined candidates exhibited considerable inhibitory activity against the PDE-4B enzyme. The four compounds (4i, 4k, 4p, and 4q) exhibited the highest potency (IC50 = 7.25, 7.15, 5.50, 7.19 nM, respectively) with no significant inhibition difference from roflumilast (no statistical difference at p < 0.05). Interestingly, compound 4p with 3-OH and 4-OCH3 substituents was found to be the most potent against PDE-4B enzyme (IC50 = 5.50 nM), compared to that of roflumilast (IC50 = 2.36 nM). Moreover, the most potent derivatives 4i, 4k, 4p, and 4q were further tested for PDE-4D inhibitory activity to investigate their PDE-4D/PDE-4B selectivity ratio. Compound 4k showed the highest selectivity towards PDE-4B isozyme more than the reference drug roflumilast (PDE-4D/4B IC50 ratio for compound 4k and roflumilast = 3.22 and 3.02, respectively). Additionally, compound 4p was chosen to test its selectivity for PDE-4B over PDE-8A, PDE-11A, and PDE-1B compared to thereference drug roflumilast. Compound 4p showed approximately 6-fold selectivity for PDE-4B over PDE-8A, about 5-fold selectivity for PDE-4B over PDE-11A, and about 11-fold selectivity of PDE-4B over PDE-1B. Compound 4p showed a higher selectivity towards PDE-4B than PDE-1B, more than the reference compound roflumilast. Furthermore, the most potent compounds (4i, 4k, 4p, 4q) were subjected to further investigation, and their effects on the cAMP level and percentage of inhibition of tumor necrosis factor-alpha (TNF-α) were studied and compared with reference drug roflumilast. Compound 4q showed the highest increase in the level of intracellular cAMP (6.55 ± 0.37 pmol/mL) and compound 4i showed the highest % of TNF-α inhibition (77.22 %). On the other side, a molecular docking study against PDE-4B clarified that all the examined candidates achieved nearly similar binding modes with similar orientations to that of the native roflumilast ligand and showed higher docking scores than roflumilast.

In-vitro and in-silico studies based discovery of 2-aryl-N-(4-morpholinophenyl)thiazol-4-amines as promising DNA gyrase inhibitors

Background: DNA gyrase is an important enzyme for the survival of bacteria. Many DNA gyrase inhibitors are in clinical practice. However, these inhibitors also encompass certain toxic and drug/food interactions. This warrants the development of a new template as DNA gyrase inhibitors. Therefore, this study aimed to deliver morpholine-based thiazoles (5a-5l) as safer DNA gyrase inhibitors.Methods: The 5a-5l were prepared by reacting compound 3 with various aryl thioamides. The structures of 5a-5l were ascertained by their spectral records. The 5a-5l were subjected to their antibacterial activity potential (serial plate dilution method), DNA gyrase inhibiting activity, and toxicity analysis (MTT assay) against HepG2 &amp; Vero cell lines. The in-silico studies (pharmacokinetic parameters and molecular docking) of 5a-5l were likewise performed.Results: It was surprisingly observed that the MIC values of 5a-5l were equal to the MIC values of ciprofloxacin (12.5 µg/ml) against the tested bacteria, whereas the DNA gyrase inhibitory activity (IC50 in µg/ml) of 5h (3.52), 5g (3.76), 5f (3.88), 5e (4.08), 5l (4.11), 5b (4.28), 5k (4.28), 5i (4.30), and 5d (4.32) was equal/better than ciprofloxacin (4.32). The MTT assay also implied the non-cytotoxic nature of 5a-5l against HepG2 &amp; Vero cell lines up to 200 µg/ml concentration. The docking outcomes indicated a similar binding pattern of 5a-5l and ciprofloxacin at the active site of DNA gyrase, wherein 5a-5l displayed a better binding affinity for the active site. The in-silico toxicity data employing the ProTox-II web server indicated no hepatotoxicity, carcinogenicity, immunotoxicity, mutagenicity, or cytotoxic effect of 5a-5l. Also, the SwissADME software supported the drug-likeliness properties and high gastrointestinal absorption of 5a-5l.Conclusion: Compounds 5h, 5g, 5f, 5e, 5l, 5b, 5k, 5i, and 5d are potent DNA gyrase inhibitors with promising safety profiles.Keywords: Discovery; Morpholine; Thiazole; DNA gyrase; MTT assay; Docking

Synthesis and antibacterial potential of novel thymol derivatives against methicillin-resistant Staphylococcus aureus and P. aeruginosa pathogenic bacteria.

The increasing threat of antibiotic resistance has created an urgent need for new antibacterial agents, particularly plant-based natural compounds and their derivatives. Thymol, a natural monoterpenoid phenolic compound derived from Monarda citriodora, is known for its aromatic and therapeutic properties, including antibacterial activity. This study focuses on synthesizing dihydropyrimidinone and dihydropyridine derivatives of thymol and exploring their antibacterial properties. The synthesized compounds were tested for their in vitro antibacterial potential against pathogenic microorganisms, specifically Pseudomonas aeruginosa (Gram-negative) and methicillin-resistant Staphylococcus aureus (MRSA) (Gram-positive). Among the synthesized derivatives, compound 3i (ethyl 4-(4-hydroxy-5-isopropyl-2-methylphenyl)-2-imino-6-methyl-1,2,3,4-tetrahydropyrimidine-5-carboxylate) exhibited the most promising antibacterial activity, with minimum inhibitory concentration (MIC) values of 12.5µM against P. aeruginosa and 50.0µM against MRSA. Additionally, compound 3i demonstrated a synergistic effect when combined with vancomycin, enhancing its antibacterial efficacy. The optimum fractional inhibitory concentration index (FICI) observed was 0.10 and 0.5 for MRSA and P. aeruginosa, respectively, in combination with vancomycin. In silico analysis of the physiochemical properties of 3i indicated compliance with all drug-likeness rules. Furthermore, molecular docking studies revealed that compound 3i has a stronger binding affinity to the target protein than thymol, providing valuable insights into its potential mechanism of action.

Design, synthesis and mechanistic study of N-4-Piperazinyl Butyryl Thiazolidinedione derivatives of ciprofloxacin with Anticancer Activity via Topoisomerase I/II inhibition

A new group of thiazolidine-2,4-dione derivatives of ciprofloxacin having butyryl linker 3a-l was synthesized via an alkylation of thiazolidine-2,4-diones with butyryl ciprofloxacin with yield range 48–77% andfully characterized by various spectroscopic and analytical tools. Anti-cancer screening outcomes indicated that 3a and 3i possess antiproliferative activities against human melanoma LOX IMVI cancer cell line with IC50 values of 26.7 ± 1.50 and 25.4 ± 1.43 µM, respectively, using doxorubicin and cisplatin as positive controls with an IC50 of 7.03 ± 0.40 and 5.07 ± 0.29 µM, respectively. Additionally, compound 3j showed promising anticancer activity against human renal cancer A498 cell line with IC50 value of 33.9 ± 1.91 µM while doxorubicin and cisplatin showed IC50 values of 3.59 ± 0.20 and 7.92 ± 0.45, respectively. On the other hand, compound 3i did not show considerable anti-bacterial activity against S. aureus, E. coli and P. aeruginosa, and only moderate activity against K. pneumoniae with only a tenth of the activity of ciprofloxacin, confirming the cytotoxicity observed. Mechanistically, compound 3i inhibited both topoisomerase I and II with IC50 of 4.77 ± 0.26 and 15 ± 0.81 µM. Furthermore, it induced cell cycle arrest at S phase in melanoma LOX IMVI cells. Moreover, 3i provoked substantial levels of early, late apoptosis and necrosis in melanoma LOX IMVI cell line comparable to that induced by doxorubicin. Furthermore, compound 3i increased the expression level of active caspase-3 by 49 folds higher in LOX IMVI cell, increased protein expression level of Bax more than the control by 3 folds and inhibited PARP-1by 33% in LOX IMVI. All results were supported by theoretical docking studies on both tested enzymes confirming potential cytotoxicity for the synthesized hybrids.