Attenuation of Streptozotocin-Induced Diabetic Neuropathic Allodynia by Flavone Derivative Through Modulation of GABA-ergic Mechanisms and Endogenous Biomarkers.

Diabetic neuropathic pain is one of the most devasting disorders of peripheral nervous system. The loss of GABAergic inhibition is associated with the development of painful diabetic neuropathy. The current study evaluated the potential of 3-Hydroxy-2-methoxy-6-methyl flavone (3-OH-2'MeO6MF), to ameliorate peripheral neuropathic pain using an STZ-induced hyperglycemia rat model. The pain threshold was assessed by tail flick, cold, mechanical allodynia, and formalin test on days 0, 14, 21, and 28 after STZ administration accompanied by evaluation of several biochemical parameters. Administration of 3-OH-2'-MeO6MF (1,10, 30, and 100 mg/kg, i.p) significantly enhanced the tail withdrawal threshold in tail-flick and tail cold allodynia tests. 3-OH-2'-MeO6MF also increased the paw withdrawal threshold in mechanical allodynia and decreased paw licking time in the formalin test. Additionally, 3-OH-2'-MeO6MF also attenuated the increase in concentrations of myeloperoxidase (MPO), thiobarbituric acid reactive substances (TBARS), nitrite, TNF-α, and IL 6 along with increases in glutathione (GSH). Pretreatment of pentylenetetrazole (PTZ) (40 mg/kg, i.p.) abolished the antinociceptive effect of 3-OH-2'-MeO6MF in mechanical allodynia. Besides, the STZ-induced alterations in the GABA concentration and GABA transaminase activity attenuated by 3-OH-2'-MeO6MF treatment suggest GABAergic mechanisms. Molecular docking also authenticates the involvement of α2ß2γ2L GABA-A receptors and GABA-T enzyme in the antinociceptive activities of 3-OH-2'-MeO6MF.

Synthesis, biochemical and computational evaluations of novel bis-acylhydrazones of 2,2'-(1,1'-biphenyl)-4,4'-diylbis(oxy))di(acetohydrazide) as dual cholinesterase inhibitors.

A series of twenty-seven bis(acylhydrazones) were successfully synthesized with high yields through a multistep process, which entailed the esterification of hydroxyl groups, hydrazination with an excess of hydrazine hydrate, and subsequent reactions with various carbonyl moieties (aldehydes). In the final stage of synthesis, different chemical species including aromatic, heterocyclic, and aliphatic compounds were integrated into the framework. The resulting compounds were characterized using several spectroscopic techniques (1H NMR, 13C NMR, and mass spectrometry). Their anticholinesterase activities were assessed in vitro by examining their interactions with two cholinesterase enzymes: acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Among the synthesized hits, compounds 3, 5, 6, 9-12, and 14 exhibited good to moderate inhibition of AChE. Specifically, 10 (IC50 = 26.3 ± 0.4 µM) and 11 (IC50 = 28.4 ± 0.5 µM) showed good inhibitory activity against AChE, while 9, 12, 3, and 6 exhibited significant inhibition potential against AChE with IC50 values ranging from 35.2 ± 1.1 µM to 64.4 ± 0.3 µM. On the other hand, 5 (IC50 = 22.0 ± 1.1 µM) and 27 (IC50 = 31.3 ± 1.3 µM) displayed significant, and 19 (IC50 = 92.6 ± 0.4 µM) showed moderate inhibitory potential for BChE. Notably, 5 and 27 exhibited dual inhibition of AChE and BChE, with greater potency than the standard drug galantamine. The binding patterns of these molecules within the binding cavities of AChE and BChE were anticipated by molecular docking which showed good correlation with our in vitro findings. Further structural optimization of these molecules may yield more potent AChE and BChE inhibitors.

Synthesis of novel 1,2,3-triazole-tethered N-acyl hydrazones as a new class of carbonic anhydrase II inhibitors: In vitro and in silico potentials.

Carbonic anhydrase II (CA II) is crucial for maintaining homeostasis in several processes, including respiration, lipogenesis, gluconeogenesis, calcification, bone resorption, and electrolyte balance. It is a pivotal druggable target which is implicated in glaucoma, renal, gastric, and pancreatic carcinomas, as well as in malignant brain tumours. Therefore, to identify new CA II (bovine) inhibitors, the current study was designed to synthesize a library of 20 new triazole-linked hydrazones (6a-t). All compounds were characterized by using spectroscopic techniques such as NMR and mass spectrometry. The in-vitro evaluation resulted in impressive inhibitory capability against CA II with IC50 values ranging from 9.10 ± 0.26-48.26 ± 1.30 µM. Among all derivatives, compounds 6a, 6b, 6d, 6k-6m, 6q, 6s and 6t exhibited potent inhibitory potential with 6t deemed as the most active inhibitor. Additionally, kinetic study of the hybrid 6t revealed concentration dependent type of inhibition with Ki value 7.24 ± 0.0086 µM. Furthermore, molecular docking of 6t correlates well with the kinetic analysis. The in-silico ADMET indicated that most of the synthesized compounds have properties conducive to drug development.

Phytoconstituents with cardioprotective properties: A pharmacological overview on their efficacy against myocardial infarction.

Myocardial infarction (MI) is considered one of the most common cardiac diseases and major cause of death worldwide. The prevalence of MI and MI-associated mortality have been increasing in recent years due to poor lifestyle habits viz. residency, obesity, stress, and pollution. Synthetic drugs for the treatment of MI provide good chance of survival; however, the demand to search more safe, effective, and natural drugs is increasing. Plants provide fruitful sources for powerful antioxidant and anti-inflammatory agents for prevention and/or treatment of MI. However, many plant extracts lack exact information about their possible dosage, toxicity and drug interactions which may hinder their usefulness as potential treatment options. Phytoconstituents play cardioprotective role by either acting as a prophylactic or adjuvant therapy to the concurrently used synthetic drugs to decrease the dosage or relief the side effects of such drugs. This review highlights the role of different herbal formulations, examples of plant extracts and types of several isolated phytoconstituents (phenolic acids, flavonoids, stilbenes, alkaloids, phenyl propanoids) in the prevention of MI with reported activities. Moreover, their possible mechanisms of action are also discussed to guide future research for the development of safer substitutes to manage MI.

Novel anti-tumor effect of natural products from Aloe vera resin and their in-vitro/in-silico targeting mechanism of carbonic anhydrase-II and IX.

Human carbonic anhydrase (hCA) plays a vital role in the development and progression of tumors in hypoxic conditions. Herein we report the hCA-II and hCA-IX activities of natural products isolated from Aloe vera (L.) Burm.f., to know their potential in tumors. These isolated compounds (1-10) displayed varying degrees of inhibition against hCA-II and hCA-IX. All the compounds showed potent activity against hCA-IX with IC50 values in the range of 2.9 - 29.1 µM. While for hCA-II, compounds 1, 2, 5-10 exhibited IC50 in the range of 4.7 - 23.4 µM. The most effective hCA IX and II inhibitors, 2 and 5, were chosen for in vitro mechanism studies, revealing that they are competitive inhibitors. Furthermore, when tested for their cytotoxic effect on BJ (normal) cell line, all the compounds showed no cytotoxic behavior, while on Prostate cancer cells (PC-3), compounds 1, 3, 5, 7, and 9 exhibited significant antiproliferative activity. Molecular docking was also conducted within the hCA IX and hCA-II active sites to observe their binding capability. Compounds 1, 5, 7, and 9 were active against both isozymes of hCA and in the PC-3 cell line, therefore these are the best choices for further in vivo studies..

Synthesis of 3-hydroxy-2-naphthohydrazide-based hydrazones and their implications in diabetic management via in vitro and in silico approaches.

Diabetes mellitus (DM) has prevailed as a chronic health condition and has become a serious global health issue due to its numerous consequences and high prevalence. We have synthesized a series of hydrazone derivatives and tested their antidiabetic potential by inhibiting the essential carbohydrate catabolic enzyme, "α-glucosidase." Several approaches including fourier transform infrared, 1 H NMR, and 13 C NMR were utilized to confirm the structures of all the synthesized derivatives. In vitro analysis of compounds 3a-3p displayed more effective inhibitory activities against α-glucosidase with IC50 in a range of 2.80-29.66 µM as compared with the commercially available inhibitor, acarbose (IC50 = 873.34 ± 1.67 M). Compound 3h showed the highest inhibitory potential with an IC50 value of 2.80 ± 0.03 µM, followed by 3i (IC50 = 4.13 ± 0.06 µM), 3f (IC50 = 5.18 ± 0.10 µM), 3c (IC50 = 5.42 ± 0.11 µM), 3g (IC50 = 6.17 ± 0.15 µM), 3d (IC50 = 6.76 ± 0.20 µM), 3a (IC50 = 9.59 ± 0.14 µM), and 3n (IC50 = 10.01 ± 0.42 µM). Kinetics analysis of the most potent compound 3h revealed a concentration-dependent form of inhibition by 3h with Ki value = 4.76 ± 0.0068 µM. Additionally, an in silico docking approach was applied to predict the binding patterns of all the compounds, which indicates that the hydrazide and the naphthalene-ol groups play a vital role in the binding of the compounds with the essential residues (i.e., Glu277 and Gln279) of the α-glucosidase enzyme.

A High Dose of Calcitriol Inhibits Glycolysis and M2 Macrophage Polarization in the Tumor Microenvironment by Repressing mTOR Activation: in vitro and Molecular Docking Studies.

BACKGROUND/AIMS: Macrophages interact with tumor cells within the tumor microenvironment (TME), which plays a crucial role in tumor progression. Cancer cells also can instruct macrophages to facilitate the spread of cancer and the growth of tumors. Thus, modulating macrophages-cancer cells interaction in the TME may be therapeutically beneficial. Although calcitriol (an active form of vitamin D) has anticancer properties, its role in TME is unclear. This study examined the role of calcitriol in the regulation of macrophages and cancer cells in the TME and its influence on the proliferation of breast cancer cells. METHODS: We modeled the TME, in vitro, by collecting conditioned medium from cancer cells (CCM) and macrophages (MCM) and culturing each cell type separately with and without (control) a high-dose (0.5 µM) calcitriol (an active form of vitamin D). An MTT assay was used to examine cell viability. Apoptosis was detected using FITC (fluorescein isothiocyanate) annexin V apoptosis detection kit. Western blotting was used to separate and identify proteins. Quantitative real-time PCR was used to analyze gene expression. Molecular docking studies were performed to evaluate the binding type and interactions of calcitriol to the GLUT1 and mTORC1 ligand-binding sites. RESULTS: Calcitriol treatment suppressed the expression of genes and proteins implicated in glycolysis (GLUT1, HKII, LDHA), promoted cancer cell apoptosis, and reduced viability and Cyclin D1gene expression in MCM-induced breast cancer cells. Additionally, calcitriol treatment suppressed mTOR activation in MCM-induced breast cancer cells. Molecular docking studies further showed efficient binding of calcitriol with GLUT1 and mTORC1. Calcitriol also inhibited CCM-mediated induction of CD206 and increased TNFα gene expression in THP1-derived macrophages. CONCLUSION: The results suggest that calcitriol may impact breast cancer progression by inhibiting glycolysis and M2 macrophage polarization via regulating mTOR activation in the TME and warrants further investigation in vivo.

Synthesis, biological evaluation, and molecular docking study of chromen-linked hydrazine carbothioamides as potent α-glucosidase inhibitors.

Inhibiting α-glucosidase is a reliable method for reducing blood sugar levels in diabetic individuals. Several novel chromen-linked hydrazine carbothioamide (3a-r) were designed and synthesized by condensation of chromone-3-carbaldehyde with a variety of substituted thiosemicarbazides. The structures of these new analogues were elucidated through various advanced spectroscopic techniques (1 H NMR, 13 C NMR, and ESI-MS). The resulted compounds were screened for α-glucosidase inhibitory potential and all the compounds (3a-r) exhibited potent inhibition of α-glucosidase with IC50 values ranging 0.29-53.70 µM. Among them compounds 3c, 3f, 3h, and 3r displayed the highest α-glucosidase inhibitor capability with IC50 values of 1.50, 1.28, 1.08, and 0.29 µM, respectively. Structure-activity relationship showed that different substituted groups are responsible for the variation in the α-glucosidase inhibition. The kinetics studies of the most active inhibitor (3r) were performed, to investigate the mode of inhibition and dissociation constants (Ki), that indicated a competitive inhibitor with Ki value of 1.47 ± 0.31 µM. Furthermore, molecular docking studies was performed to reveal the possible interactions, such as H-bonding, or π-π stacking, with the key residues of α-glucosidase. Docking analysis revealed the importance of hydrazine carbothioamide moiety of compounds in the attachment of ligands with the crucial residues of α-glucosidase. The estimated pharmacokinetic, physicochemical, and drug likeness properties of compounds 3a-r reflects that these molecules have acceptable range of these properties.

Isoxazole analogues of dibenzazepine as possible leads against ulcers and skin disease: In vitro and in silico exploration.

Utilizing multi-target drugs shows great promise as an effective strategy against polygenic diseases characterized by intricate patho-mechanisms, such as ulcers, skin dermatitis, and cancers. The current research centers around the creation of hybrid compounds, connecting dibenzazepine and isoxazole, with the aim of exploring their potential as inhibitors for urease and tyrosinase enzymes. Analogs 6a, 6b, 6d, 6 h-6j, and 6 l demonstrated strong inhibitory potential against tyrosinase enzyme with IC50 values of 4.32 ± 0.31-12.36 ± 0.48. Whereas analogs 6a, 6c, 6e, 6f, 6h-6m, and 6r exhibited potent inhibitory activities against urease enzyme with IC50 values of 3.67 ± 0.91-15.60 ± 0.18 µM. Furthermore, compounds 6i, 6n, and 6r showed weak toxic effect in BJ-cell line, whereas the remaining compounds were found non-toxic to normal cell line. The mechanistic studies of potent inhibitors of both the enzymes showed competitive mode of inhibition. Molecular docking was employed to establish the relationship between structure and activity and to elucidate the interaction mechanism. This analysis revealed that the active analogs exhibited crucial interactions with the active site residues of urease and tyrosinase, thus corroborating our experimental results. Hence, the generated derivatives of dibenzazepine-linked isoxazoles present intriguing starting points for further investigations into their potential as inhibitors of urease and tyrosinase, with the potential for future modification and enhancement.

Novel Bis-Schiff's base derivatives of 4-nitroacetophenone as potent α-glucosidase agents: Design, synthesis and in silico approach.

Bis-Schiff's base derivatives of 4-nitroacetophenone (1-18) were synthesized in good yields by reacting hydrazone of 4-nitroacetophenone with substituted aldehydes and ketones with catalytic amount of acetic acid. The structures of synthesized products (1-18) were deduced with the help of spectroscopic techniques like 1H NMR, 13C NMR and HR-ESIMS. The synthesized bis-Schiff's bases were assessed for their α-glucosidase inhibitory activity where compound 4 (IC50 = 2.79 ± 0.04 µM), 1 (IC50 = 9.76 ± 0.31 µM), 6 (IC50 = 11.37 ± 0.20 µM), 17 (IC50 = 14.10 ± 0.12 µM), 14 (IC50 = 17.21 ± 0.28 µM), and 8 (IC50 = 20.73 ± 0.53 µM), showed a very high potential for inhibition of α-glucosidase. Compounds 11, 15, 16, 2, 18, 7, and 5 showed significant inhibition against alpha-glucosidase with IC50 values 22.98 ± 0.34, 24.45 ± 0.53, 27.31 ± 0.29, 40.56 ± 0.60, 41.58 ± 0.47, 46.53 ± 0.76, and 47.46 ± 0.89 µM, respectively. Furthermore, compound 10 (IC50 = 52.63 ± 0.74 µM), 12 (IC50 = 70.80 ± 3.59 µM), 3 (IC50 = 82.68 ± 0.69 µM), 13 (IC50 = 88.89 ± 4.25 µM), and 9 (IC50 = 94.58 ± 0.86 µM) showed moderate activity towards the inhibition of α-glucosidase enzyme. All these compounds were compared with acarbose (IC50 = 875.75 ± 1.24 µM) as a standard α-glucosidase inhibitor. Molecular docking was used to know the molecular bases of such high activities against α-glucosidase. High docking scores were recorded implying significant interactions between the active compounds and amino acid residues of the active site of α-glucosidase.

Synthesis of novel hybrid pharmacophore of N-((4-sulfamoylphenyl)carbamothioyl)alkanamides as potent carbonic anhydrase-II and 15-lipoxygenase inhibitors.

A series of N-((4-sulfamoylphenyl)carbamothioyl)alkanamides (5a-j) were synthesized by the reaction of sulphanilamide in dry acetone with freshly prepared alkyl and acyl isothiocyanates (5a-j). The structures of products were confirmed by IR, 1 H, and 13 C NMR. The synthesized compounds were screened as inhibitors of the bovine erythrocyte carbonic anhydrase isoform II (bCA II) and 15-lipoxygenase enzyme (15-LOX). Most of the derivatives showed significant activity against bCA-II while only few compounds were found active against 15-LOX. Molecular docking studies of most active compounds were carried out against bCA II as well as 15-LOX to rationalize the binding mode and interactions of compound in the active sites. Additionally, the pharmacokinetic properties of the compounds were predicted through computational tools, which reflect that these compounds possess acceptable pharmacokinetic profile and good drug-likeness.

Design, Synthesis and Molecular Docking Study of Novel 3-Phenyl-ß-Alanine-Based Oxadiazole Analogues as Potent Carbonic Anhydrase II Inhibitors.

Carbonic anhydrase-II (CA-II) is strongly related with gastric, glaucoma, tumors, malignant brain, renal and pancreatic carcinomas and is mainly involved in the regulation of the bicarbonate concentration in the eyes. With an aim to develop novel heterocyclic hybrids as potent enzyme inhibitors, we synthesized a series of twelve novel 3-phenyl-ß-alanine 1,3,4-oxadiazole hybrids (4a-l), characterized by 1H- and 13C-NMR with the support of HRESIMS, and evaluated for their inhibitory activity against CA-II. The CA-II inhibition results clearly indicated that the 3-phenyl-ß-alanine 1,3,4-oxadiazole derivatives 4a-l exhibited selective inhibition against CA-II. All the compounds (except 4d) exhibited good to moderate CA-II inhibitory activities with IC50 value in range of 12.1 to 53.6 µM. Among all the compounds, 4a (12.1 ± 0.86 µM), 4c (13.8 ± 0.64 µM), 4b (19.1 ± 0.88 µM) and 4h (20.7 ± 1.13 µM) are the most active hybrids against carbonic CA-II. Moreover, molecular docking was performed to understand the putative binding mode of the active compounds. The docking results indicates that these compounds block the biological activity of CA-II by nicely fitting at the entrance of the active site of CA-II. These compounds specifically mediating hydrogen bonding with Thr199, Thr200, Gln92 of CA-II.

Microscale Thermophoresis and Molecular Modelling to Explore the Chelating Drug Transportation in the Milk to Infant.

The microscale thermophoresis (MST) technique was utilized to investigate lactoferrin-drug interaction with the iron chelator, deferiprone, using label-free system. MST depends on the intrinsic fluorescence of one interacting partner. The results indicated a significant interaction between lactoferrin and deferiprone. The estimated binding constant for the lactoferrin-deferiprone interaction was 8.9 × 10-6 ± 1.6, SD, which is to be reported for the first time. Such significant binding between lactoferrin and deferiprone may indicate the potentiation of the drug secretion into a lactating mother's milk. The technique showed a fast and simple approach to study protein-drug interaction while avoiding complicated labeling procedures. Moreover, the binding behavior of deferiprone within the binding sites of lactoferrin was investigated through molecular docking which reflected that deferiprone mediates strong hydrogen bonding with ARG121 and ASP297 in pocket 1 and forms H-bond and ionic interaction with ASN640 and ASP395, respectively, in pocket 2 of lactoferrin. Meanwhile, iron ions provide ionic interaction with deferiprone in both of the pockets. The molecular dynamic simulation further confirmed that the binding of deferiprone with lactoferrin brings conformational changes in lactoferrin that is more energetically stable. It also confirmed that deferiprone causes positive correlation motion in the interacting residues of both pockets, with strong negative correlation motion in the loop regions, and thus changes the dynamics of lactoferrin. The MM-GBSA based binding free energy calculation revealed that deferiprone exhibits ∆G TOTAL of -63,163 kcal/mol in pocket 1 and -63,073 kcal/mol in pocket 2 with complex receptor-ligand difference in pocket 1 and pocket 2 of -117.38 kcal/mol and -111.54 kcal/mol, respectively, which in turn suggests that deferiprone binds more strongly in the pocket 1. The free energy landscape of the lactoferrin-deferiprone complex also showed that this complex remains in a high energy state that confirms the strong binding of deferiprone with the lactoferrin. The current research concluded that iron-chelating drugs (deferiprone) can be transported from the mother to the infant in the milk because of the strong attachment with the lactoferrin active pockets.

Therapeutic potential of N4-substituted thiosemicarbazones as new urease inhibitors: Biochemical and in silico approach.

Urease enzyme plays a key role in pathogenesis of gastritis and peptic ulcers. Its inhibition averts our bodies from many disorders including formation of urinary calculi. In agriculture, the high urease content causes severe environmental and hence economic problems. Due to deficiency of effective and safer drugs to tackle the aforementioned disorders, the quest for new scaffolds becomes mandatory in the field of medicinal chemistry. In this regard, we herein report a new series of N4-substituted thiosemicarbazones 3a-v as potential candidates for urease inhibition. These new N4-substituted thiosemicarbazones 3a-v of distant chemical scaffolds were characterized by advanced spectroscopic techniques, such as FTIR, 1HNMR, 13CNMR, ESI-MS and in the case of compound 3g by single crystal X-ray analysis. The compounds were evaluated for their urease inhibitory potential. All newly synthesized compounds showed significant urease inhibitions with IC50 values in range of 2.7 ± 0.320-109.2 ± 3.217 µM. Molecular docking studies were used for interactions pattern and structure-activity relationship for all compounds, which demonstrated excellent binding interactions with the active site residues, such as hydrogen bonding, π-π interactions, π-H and nickel atom coordination.

Biomedical Applications of Scutellaria edelbergii Rech. f.: In Vitro and In Vivo Approach.

In the current study, in vitro antimicrobial and antioxidant activities and in vivo anti-inflammatory and analgesic activities of Scutellaria edelbergii Rech. f. (crude extract and subfractions, i.e., n-hexane, ethyl acetate (EtOAc), chloroform, n-butanol (n-BuOH) and aqueous) were explored. Initially, extraction and fractionation of the selected medicinal plant were carried out, followed by phytochemical qualitative tests, which were mostly positive for all the extracts. EtOAc fraction possessed a significant amount of phenolic (79.2 ± 0.30 mg GAE/g) and flavonoid (84.0 ± 0.39 mg QE/g) content. The EtOAc fraction of S. edelbergii exhibited appreciable antibacterial activity against Gram-negative (Escherichia coli and Klebsiella pneumoniae) strains and significant zones of inhibition were observed against Gram-positive bacterial strains (Bacillus subtilis and Staphylococcus aureus). However, it was found inactive against Candida Albicans and Fusarium oxysporum fungal strains. The chloroform fraction was the most effective with an IC50 value of 172 and 74 µg/mL against DPPH (1,1-Diphenyl-2-picryl-hydrazyl) and ABTS assays, in comparison with standard ascorbic acid 59 and 63 µg/mL, respectively. Moreover, the EtOAc fraction displayed significant in vivo anti-inflammatory activity (54%) using carrageenan-induced assay and significant (55%) in vivo analgesic activity using acetic acid-induced writing assay. In addition, nine known compounds, ursolic acid (UA), ovaul (OV), oleanolic acid (OA), ß-sitosterol (BS), micromeric acid (MA), taraxasterol acetate (TA), 5,3',4'-trihydroxy-7-methoxy flavone (FL-1), 5,7,4'-trihydroxy-6,3'-dimiethoxyflavone (FL-2) and 7-methoxy catechin (FL-3), were isolated from methanolic extract of S. edelbergii. These constituents have never been obtained from this source. The structures of all the isolated constituents were elucidated by spectroscopic means. In conclusion, the EtOAc fraction and all other fractions of S. edelbergii, in general, displayed a significant role as antibacterial, free radical scavenger, anti-inflammatory and analgesic agents which may be due to the presence of these constituents and other flavonoids.

New Carbonic Anhydrase-II Inhibitors from Marine Macro Brown Alga Dictyopteris hoytii Supported by In Silico Studies.

In continuation of phytochemical investigations of the methanolic extract of Dictyopteris hoytii, we have obtained twelve compounds (1-12) through column chromatography. Herein, three compounds, namely, dimethyl 2-bromoterepthalate (3), dimethyl 2,6-dibromoterepthalate (4), and (E)-3-(4-(dimethoxymethyl)phenyl) acrylic acid (5) are isolated for the first time as a natural product, while the rest of the compounds (1, 2, 6-12) are known and isolated for the first time from this source. The structures of the isolated compounds were elucidated by advanced spectroscopic 1D and 2D NMR techniques including 1H, 13C, DEPT, HSQC, HMBC, COSY, NEOSY, and HR-MS and comparison with the reported literature. Furthermore, eight compounds (13-20) previously isolated by our group from the same source along with the currently isolated compounds (1-12) were screened against the CA-II enzyme. All compounds, except 6, 8, 14, and 17, were evaluated for in vitro bovine carbonic anhydrase-II (CA-II) inhibitory activity. Eventually, eleven compounds (1, 4, 5, 7, 9, 10, 12, 13, 15, 18, and 19) exhibited significant inhibitory activity against CA-II with IC50 values ranging from 13.4 to 71.6 µM. Additionally, the active molecules were subjected to molecular docking studies to predict the binding behavior of those compounds. It was observed that the compounds exhibit the inhibitory potential by specifically interacting with the ZN ion present in the active site of CA-II. In addition to ZN ion, two residues (His94 and Thr199) play an important role in binding with the compounds that possess a carboxylate group in their structure.

Robust therapeutic potential of carbazole-triazine hybrids as a new class of urease inhibitors: A distinctive combination of nitrogen-containing heterocycles.

The inhibition of urease enzyme is very important as it plays a key role in the treatment of several urinary and gastrointestinal tract infections. This enzyme provides a suitable environment for Helicobacter pylori at the low pH of the stomach, a causative agent of gastric and peptic ulcer that may lead to cancer. In agriculture, the high urease content causes environmental and economic problems. In this pursuit, given the well-established importance of integrated pharmacophores in medicinal chemistry and to explore new inhibitors of urease featuring two distinct heterocyclic functionalities, we herein report a facile synthesis of carbazole-triazine hybrids (3a-j). These new propeller-shaped chemical scaffolds were evaluated for their urease inhibitory potential in order to identify suitable leads. The initial structure-activity survey work guided through in vitro bioactivity results recognized 3e and 3f as new starting point hits incorporating bulky iodo (3e) and strong electron-withdrawing nitro (3f) groups at the para-position of aryl amine component. The potent compounds (3e &3f) exhibited the highest activity with IC50 values of 5.6 and 6.7 µM, respectively. In the molecular docking analysis, these compounds depicted excellent binding interactions with the active site residues. The key interactions observed include hydrogen bonding, π-π interactions, π-cation and nickel atom coordination to the triazine nitrogen of both inhibitors.

Synthesis, characterization and molecular docking of some novel hydrazonothiazolines as urease inhibitors.

A series of new hydrazonothiazolines (3a-v) was obtained in good to excellent yields (79-96%) via cyclization of the appropriate thiosemicarbazones with phenacyl bromide. The targeted compounds were characterized by advanced spectroscopic techniques, such as FTIR, 1HNMR, 13CNMR and ESI-MS. The structure of compounds 3n and 3v was unambiguously confirmed by single crystal X-ray analysis. All compounds displayed enhanced inhibitory activity against urease enzyme with IC50 values in range of 1.73 ±â€¯1.57-27.3 ±â€¯0.655 µM when compared to standard thiourea (IC50 = 20.8 ±â€¯0.75 µM). The structure-activity relationship studies demonstrated that the activity of this series is due the central thiazole ring that interacts with nickel atoms in the active site of urease enzyme. Moreover, molecular docking studies were carried out to investigate the binding mode of all active compounds and an inactive (3u) with the active site of the urease enzyme. The docking results are in complete agreement with the experimental finding.

Photocatalytic Decolorization and Biocidal Applications of Nonmetal Doped TiO2: Isotherm, Kinetic Modeling and In Silico Molecular Docking Studies.

Textile dyes and microbial contamination of surface water bodies have been recognized as emerging quality concerns around the globe. The simultaneous resolve of such impurities can pave the route for an amicable technological solution. This study reports the photocatalytic performance and the biocidal potential of nitrogen-doped TiO2 against reactive black 5 (RB5), a double azo dye and E. coli. Molecular docking was performed to identify and quantify the interactions of the TiO2 with ß-lactamase enzyme and to predict the biocidal mechanism. The sol-gel technique was employed for the synthesis of different mol% nitrogen-doped TiO2. The synthesized photocatalysts were characterized using thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) and diffuse reflectance spectroscopy (DRS). The effects of different synthesis and reaction parameters were studied. RB5 dye degradation was monitored by tracking shifts in the absorption spectrum and percent chemical oxygen demand (COD) removal. The best nanomaterial depicted 5.57 nm crystallite size, 49.54 m2 g-1 specific surface area, 11-40 nm particle size with spherical morphologies, and uniform distribution. The RB5 decolorization data fits well with the pseudo-first-order kinetic model, and the maximum monolayer coverage capacity for the Langmuir adsorption model was found to be 40 mg g-1 with Kads of 0.113 mg-1. The LH model yielded a higher coefficient KC (1.15 mg L-1 h-1) compared to the adsorption constant KLH (0.3084 L mg-1). 90% COD removal was achieved in 60 min of irradiation, confirmed by the disappearance of spectral peaks. The best-optimized photocatalysts showed a noticeable biocidal potential against human pathogenic strain E. coli in 150 min. The biocidal mechanism of best-optimized photocatalyst was predicted by molecular docking simulation against E. coli ß-lactamase enzyme. The docking score (-7.6 kcal mol-1) and the binding interaction with the active site residues (Lys315, Thr316, and Glu272) of ß-lactamase further confirmed that inhibition of ß-lactamase could be a most probable mechanism of biocidal activity.

Developing new hybrid scaffold for urease inhibition based on carbazole-chalcone conjugates: Synthesis, assessment of therapeutic potential and computational docking analysis.

Although a diverse range of chemical entities offering striking therapeutic potential against urease enzyme has been reported, the key challenges (toxicity and safety) associated with these inhibitors create a large unmet medical need to unveil new, potent and safe inhibitors of urease enzyme. In this pursuit, the present study demonstrates the successful synthesis of carbazole-chalcone hybrids (4a-n) in good yields. The evaluation of the preliminary in vitro biological results showed that selected members of the investigated library of hybrid compounds possess excellent urease inhibitory efficacy. In particular, compounds 4c and 4k were the most potent inhibitors with lowest IC50 values of 8.93 ±â€¯0.21 and 6.88 ±â€¯0.42 µM, respectively. Molecular docking analysis of the most potent inhibitor 4k suggests that the compound is fitted neatly at the active site interface and mediates interaction with both nickel atoms present in the active site. Several other obvious interactions including metal-carbonyl contact, hydrogen bonding and hydrophobic interactions were also observed, playing a crucial part in the stabilization of 4k in the active site of urease.