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The two cationic palladium(II) complexes, [Pd(Len)2][OTf]2 (4) and [Pd(Lphen)2][OTf]2 (5), were synthesized by treatment of bis(benzonitrile)dichloropalladium(II) with [H2Len][OTf]2 (2) or [H2Lphen][OTf]2 (3), respectively, in the presence of a weak base. The pro-ligands 2 and 3 were synthesized by melt reactions between N-methyl-4-chloropyridinium triflate (1) and the amines ethylenediamine or phenylenediamine, respectively. The water-soluble compounds 2–5 were fully characterized, including by single-crystal X-ray crystal structure determinations for 2–4. UV-Vis and fluorescence spectroscopy were used to study the binding interactions of 2–5 with CT-DNA. The spectroscopic data suggested the presence of intercalative and groove binding modes and this was supported by molecular docking studies. The in vitro cytotoxicity studies (IC50 values) showed that the human breast cancer cell lines MCF-7 and T47D were more sensitive towards 3, 4 and 5 than cisplatin. The cytotoxicity of the new compounds decreased in the order 5 > 4 > 3 > 2. Furthermore, the annexin V-FITC staining method strongly suggested the presence of phosphatidylserine (PS) on the outer membrane of the treated cells, which is a hallmark of apoptosis. [ABSTRACT FROM AUTHOR]

The present study describes efficient and facile syntheses of varyingly substituted 3-thioaurones from the corresponding 3-oxoaurones using Lawesson’s reagent and phosphorous pentasulfide. In comparison, the latter methodology was proved more convenient, giving higher yields and required short and simple methodology. The structures of synthetic compounds were unambiguously elucidated by IR, MS and NMR spectroscopy. All synthetic compounds were screened for their inhibitory potential against in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Molecular docking studies were also performed in order to examine their binding interactions with AChE and BChE human proteins. Both studies revealed that some of these compounds were found to be good inhibitors against AChE and BChE. [ABSTRACT FROM AUTHOR]

Targeting tyrosinase (TYR), a key enzyme responsible for melanogenesis disorders, is a well-known approach utilized for the development of melanogenesis inhibitor. A variety of dermatological disorders and microbial skin infections can cause hyperpigmentation. Hence, exploring new scaffolds for the treatment of melanogenesis disease is an inspiring goal. In this context, a series of varyingly substituted flavone-based hydrazones have been designed, synthesized and characterized successfully. The present study describes the discovery of novel mushroom tyrosinase inhibitors (TIs) for treating hyperpigmentation. In due course, flavone scaffold has been incorporated into the novel chemotypes that exhibit in vitro inhibitory effects against mushroom tyrosinase for the purpose of discovering anti‐melanogenic agents. Biological investigations of prepared analogs herein demonstrated moderate to excellent activity against most of the fungal-bacterial strains and their activity is comparable to those of commercially available antibiotics i.e., Ciprofloxacin and Ketoconazole. Based on in vitro tyrosinase inhibitory assay, some compounds exhibited potent inhibition particularly, 3g (IC 50 = 1.40 ± 0.16 µM), 3j (IC 50 = 0.95 ± 0.07 µM), 3o (IC 50 = 1.13 ± 0.11 µM), and 3q (IC 50 = 1.01 ± 0.1 µM) showed best inhibition i.e. , 0.7, 0.5, 0.6 and 0.5 folds, respectively, than kojic acid (IC 50 = 1.79 ± 0.6 µM). Lineweaver-Burk plots demonstrated that the most potential derivative 3j tyrosinase inhibition proceeds via non-competitive pathway and the Michaelis-Menton constant (K m) value is 0.0265. Molecular modeling was performed for all tested analogs (3a–3q) using a model of mushroom tyrosinase to find crucial binding modes liable for inhibitory activity. The SARs were preliminarily examined, and the docking study revealed that analogs 3j, 3o and 3p had a strong binding association to tyrosinase (2Y9X). Furthermore, a drug-likeness study was employed and confirmed the favorable activity of the new analogs as a new anti-tyrosinase agent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design and synthesis of 2-phenylchromones as the potent tyrosinase inhibitors. • Compound 10 showed the excellent inhibitory activity (IC 50 = 0.093 ± 0.003 µg/ml). • Molecular docking studies of these compounds were performed. • Structure-activity relationship (SAR) was established. • ADME screening (in silico) of the synthesized analogues displayed drug-like nature. The present study describes the discovery of novel inhibitors of mushroom tyrosinase enzyme. For that purpose, a series of varyingly substituted 2-phenylchromone analogues 1–28 were synthesized and characterized in detail by various spectroscopic techniques (UV–Vis, FTIR, 1H NMR, 13C NMR) and mass spectrometry. All the derivatives (1–28) were screened in vitro for their inhibitory potential against mushroom tyrosinase enzyme. Interestingly, all the synthetic compounds displayed good to excellent inhibitory activity with IC 50 values ranging from 0.093 ± 0.003 μg/ml to 23.58 ± 0.94 μg/ml for brominated 3-hydroxy-2-phenylchromones and 0.22 ± 0.017 μg/ml to 22.22 ± 1.1 μg/ml for brominated 2-phenylchromones against tyrosinase in comparison to the standard kojic acid (IC 50 = 1.79 ± 0.64 μg/ml). Remarkably, the bromine atoms attached on ring A attribute to increases the inhibitory potential of 2-phenylchromone moiety and anti-tyrosinase assay demonstrated that compound 10 (IC 50 = 0.093 ± 0.003 µg/ml) was found almost nineteenfold , 11 (IC 50 = 0.126 ± 0.015 µg/ml) fourteenfold and 26 (IC 50 = 0.22 ± 0.017 µg/ml) about eightfold more active than the positive control. Notably, among the already literature reported tyrosinase inhibitors, these analogues have been found the most active inhibitors of mushroom tyrosinase with the lowest possible IC 50 values. To design and develop novel tyrosinase inhibitors using 2-phenylchromone as a structural motif in the future, a limited structure-activity relationship was established. Moreover, in silico studies were carried out to rationalize the binding mode of interactions of all the targeted compounds (1–28) with the active site of enzymes. The experimental and theoretical results are in parallel with one another. In addition, molecular description was performed with the drug-likeness and bioactivity scores. Computational analysis predicted that few compounds are in a linear correlation with Lipinski's RO5 indicating superb drug-likeness and bioactivity score for drug targets. [ABSTRACT FROM AUTHOR]

• A series of new flavonols and 4-thioflavonols were designed, synthesized and characterized efficiently. • The inhibitory potentials of all the synthesized compounds were evaluated against cholinesterase enzymes. • Structure-activity relationship was established. • In silico molecular modeling studies were performed. To explore new scaffolds for the treat of Alzheimer's disease appears to be an inspiring goal. In this context, a series of varyingly substituted flavonols and 4-thioflavonols have been designed and synthesized efficiently. All the newly synthesized compounds were characterized unambiguously by common spectroscopic techniques (IR, 1H-, 13C NMR) and mass spectrometry (EI-MS). All the derivatives (1 – 24) were evaluated in vitro for their inhibitory potential against cholinesterase enzymes. The results exhibited that these derivatives were potent selective inhibitors of acetylcholinesterase (AChE), except the compound 11 which was selective inhibitor of butyrylcholinesterase (BChE), with varying degree of IC 50 values. Remarkably, the compounds 20 and 23 have been found the most potent almost dual inhibitors of AChE and BChE amongst the series with IC 50 values even less than the standard drug. The experimental results in silico were further validated by molecular docking studies in order to find their binding modes with the active pockets of AChE and BChE enzymes. [ABSTRACT FROM AUTHOR]

• New analogs of N -(3-trifluoromethyl)benzoyl- N′ -aryl thiourea are reported. • All synthesized compounds were screened for their antibacterial, antifungal, antioxidant and cytotoxic activities with some significant results. • These compounds were also evaluated for their antiurease potential with promising results. • All the synthesized compounds were docked into the binding cavity of Urease and showed valuable interactions with the target protein along with good docking scores. • Thus we propose the synthesized compounds to be used as potent urease inhibitors after further detailed mechanistic studies. An irrefutable advancement has been noted for the infectious diseases caused due to ureolytic bacteria through the development of various drugs. Keeping in mind the extremely valuable synthetic utility and medicinal significance of thiourea derivatives, synthesis of new 3-trifluoromethyl benzoic acid thiourea derivatives (3a–j) were carried out. The biological potential of all compounds in terms of antimicrobial, antioxidant, cytotoxic and antiurease activities were studied. The compounds 3a, 3c and 3i with dichloro and methoxy groups substitution on the aryl group showed significant activity against all strain of bacteria while moderate to no activity was observed in remaining compounds. Whereas the antifungal evaluation showed that all compounds were active againts C. Albican and no activity was observed against C. Prapsilosis. The cytotoxic findings revealed the non-toxic nature of these compounds as IC 50 values of majority of the compounds are above 100 μm except for compounds 3f and 3g. In addition, these compounds exhibited better antioxidant potential as 100 μm concentration inhibited >50% reactive oxygen species (ROS) production except compounds 3e, 3f and 3j. The compound 3a proved to be the most potent urease inhibitor showing the highest enzyme % inhibition (93.1%) with IC 50 value of 8.17 ± 0.24 µM and found more active as compare to standard followed by compound 3e (92.6%), 3h (91.6%), 3d (90.8%), 3b (90.6%) and 3f (90.0%) with their respective IC 50 values. All the synthesized compounds were docked into the binding cavity of Urease (PDB ID: 4ubp). The most active compound 3a was also ranked as top on the docking score as it was found to show valuable interactions with the target protein along with good docking scores. Hence our results revealed that the synthesized compounds have potential to be used as potent urease inhibitors after further detailed mechanistic studies. [ABSTRACT FROM AUTHOR]