Synthesis and urease inhibitory potential of benzophenone sulfonamide hybrid in vitro and in silico.

This study deals with the synthesis of benzophenone sulfonamides hybrids (1-31) and screening against urease enzyme in vitro. Studies showed that several synthetic compounds were found to have good urease enzyme inhibitory activity. Compounds 1 (N'-((4'-hydroxyphenyl)(phenyl)methylene)-4''-nitrobenzenesulfonohydrazide), 2 (N'-((4'-hydroxyphenyl)(phenyl)methylene)-3''-nitrobenzenesulfonohydrazide), 3 (N'-((4'-hydroxyphenyl)(phenyl)methylene)-4''-methoxybenzenesulfonohydrazide), 4 (3'',5''-dichloro-2''-hydroxy-N'-((4'-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide), 6 (2'',4''-dichloro-N'-((4'-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide), 8 (5-(dimethylamino)-N'-((4-hydroxyphenyl)(phenyl)methylene)naphthalene-1-sulfono hydrazide), 10 (2''-chloro-N'-((4'-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide), 12 (N'-((4'-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide) have found to be potently active having an IC50 value in the range of 3.90-17.99 µM. These compounds showed superior activity than standard acetohydroxamic acid (IC50 = 29.20 ±â€¯1.01 µM). Moreover, in silico studies on most active compounds were also performed to understand the binding interaction of most active compounds with active sites of urease enzyme. Structures of all the synthetic compounds were elucidated by 1H NMR, 13C NMR, EI-MS and FAB-MS spectroscopic techniques.

Biology-oriented drug synthesis (BIODS), in vitro urease inhibitory activity, and in silico study of S-naproxen derivatives.

Current study is based on the biology-oriented drug synthesis (BIODS) of S-naproxen (NSAID) derivatives and the evaluation of their urease inhibitory potential. In this regard, a variety of S-naproxen derivatives 2-39 including hydrazide 1, Schiff bases 2-21, aroyl substituted hydrazides 22-24, sulfohydrazides 25-34, 2-mercapto oxadiazole 35, phenacyl substituted 2-mercapto oxadiazoles 36-39 were synthesized under the umbrella of BIODS by simple chemical transformation of its pharmacophoric carboxylic group. Compounds 1-39 were evaluated for in vitro urease inhibitory activity and most of them showed good to moderate inhibitory potential in the range of IC50 = 14.01 ±â€¯0.23-76.43 ±â€¯0.8 µM as compared to standard acetohydroxamic acid (IC50 = 27.0 ±â€¯0.5 µM). Limited structure-activity relationship (SAR) was established in order to rationalize the participation of varying groups (R) in the inhibitory potential of compounds. Molecular docking study on all active compounds was also carried out to decipher the interactions detail of the ligand with the receptors of active site of enzyme.

α-Glucosidase inhibitory potential and hemolytic evaluation of newly synthesized 3,4,5-trisubstituted-1,2,4-triazole derivatives.

A series of 1, 2, 4-triazole derivatives bearing piperidine moiety has been introduced as new anti-diabetic drug candidates with least cytotoxicity. p-Chlorophenylsulfonyl chloride (1) and ethyl nipecotate (2) were the starting reagents that resulted into corresponding 3,4,5-trisubstituted-1,2,4-triazole (6) through a series of steps. A series of electrophiles, 9a-e, were synthesized by reacting 4-bromobutyryl chloride (7) with differently substituted aromatic amines (8a-e) under basic aqueous medium. Target derivatives, 10a-e, were synthesized by the reaction of compound 6 with N-aryl-4-bromobutanamides (9a-e) in an aprotic solvent. Structures of all the derivatives were verified by spectroscopic analysis using IR, 1H-NMR, 13C-NMR and EIMS. Most of the derivatives revealed moderate to good α-glucosidase inhibitory activity with reference to acarbose. The moderate hemolytic potential demonstrated least toxicity.

Benzylidine indane-1,3-diones: As novel urease inhibitors; synthesis, in vitro, and in silico studies.

Current study deals with the evaluation of indane-1,3-dione based compounds as new class of urease inhibitors. For that purpose, benzylidine indane-1,3-diones (1-30) were synthesized and fully characterized by different spectroscopic techniques including EI-MS, HREI-MS, 1H, and 13C NMR. All synthetic molecules 1-30 were evaluated for urease inhibitory activity and showed good to moderate inhibitory potential within the range of (IC50 = 11.60 ±â€¯0.3-257.05 ±â€¯0.7 µM) as compared to the standard acetohydroxamic acid (IC50 = 27.0 ±â€¯0.5 µM). Compound 1 (IC50 = 11.60 ±â€¯0.3 µM) was found to be most potent inhibitor amongst all derivatives. The key binding interactions of most active compounds within the enzyme pocket were evaluated through in silico studies.

5-Acetyl-6-methyl-4-aryl-3,4-dihydropyrimidin-2(1H)-ones: As potent urease inhibitors; synthesis, in vitro screening, and molecular modeling study.

5-Acetyl-6-methyl-4-aryl-3,4-dihydropyrimidin-2(1H)-ones 1-43 were synthesized in a "one-pot" three component reaction and structurally characterized by various spectroscopic techniques such as 1H, 13C NMR, EI-MS, HREI-MS, and IR. All compounds were evaluated for their in vitro urease inhibitory activity. It is worth mentioning that except derivatives 1, 11, 12, and 14, all were found to be more potent than the standard thiourea (IC50 = 21.25 ±â€¯0.15 µM) and showed their urease inhibitory potential in the range of IC50 = 3.70 ±â€¯0.5-20.14 ±â€¯0.1 µM. Structure-activity relationship (SAR) was rationalized by looking at the varying structural features of the molecules. However, molecular modeling study was performed to confirm the binding interactions of the molecules (ligand) with the active site of enzyme.

Synthesis, enzyme inhibition and molecular docking studies of 1-Arylsulfonyl-4-phenylpiperazine derivatives.

Heterocyclic molecules have been frequently investigated to possess various biological activities during the last few decades. The present work elaborates the synthesis and enzymatic inhibition potentials of a series of sulfonamides. A series of 1-arylsulfonyl-4-Phenylpiperazine (3a-n) geared up by the reaction of 1-phenylpiperazine (1) and different (un)substituted alkyl/arylsulfonyl chlorides (2a-n), under defined pH control using water as a reaction medium. The synthesized molecules were characterized by 1H-NMR, 13C-NMR, IR and EI-MS spectral data. The enzyme inhibition study was carried on α-glucosidase, lipoxygenase (LOX), acetyl cholinesterase (AChE) and butyryl cholinesterase (BChE) enzymes supported by docking simulation studies and the IC50 values rendered a few of the synthesized molecules as moderate inhibitors of these enzymes where, the compound 3e exhibited comparatively better potency against α-glucosidase enzyme. The synthesized compounds showed weak or no inhibition against LOX, AChE and BChE enzymes.

Synthesis, pharmacological screening and computational analysis of some 2-(1H-Indol-3-yl)-N'-[(un)substituted phenylmethylidene] acetohydrazides and 2-(1H-Indol-3-yl)-N'-[(un)substituted benzoyl/2-thienylcarbonyl]acetohydrazides.

The undertaken research was initiated by transforming 2-(1H-Indol-3-yl)acetic acid (1) in catalytic amount of sulfuric acid and ethanol to ethyl 2-(1H-Indol-3-yl)acetate (2), which was then reacted with hydrazine monohydrate in methanol to form 2-(1H-Indol-3-yl)acetohydrazide (3). Further, The reaction scheme was designed into two pathways where, first pathway involved The reaction of 3 with substituted aromatic aldehydes (4a-o) in methanol with few drops of glacial acetic acid to generate 2-(1H-Indol-3-yl)-N'-[(un)substitutedphenylmethylidene]acetohydrazides (5a-o) and in second pathway 3 was reacted with acyl halides (6a-e) in basic aqueous medium (pH 9-10) to afford 2-(1H-Indol-3-yl)-N'-[(un)substitutedbenzoyl/2-thienylcarbonyl]acetohydrazides (7a-e). All The synthesized derivatives were characterized by IR, EI-MS and 1H-NMR spectral techniques and evaluated for their anti-bacterial potentials against Gram positive and Gram negative bacterial strains and it was found that compounds 7a-d exhibited antibacterial activities very close to standard Ciprofloxacin. The synthesized derivatives demonstrated moderate to weak anti-enzymatic potential against α-Glucosidase and Butyrylcholinesterase (BChE) where, compounds 7c and 5c exhibited comparatively better inhibition against these enzymes respectively. Compounds 7a, 7d and 7e showed excellent anti-enzymatic potentials against Lipoxygenase (LOX) and their IC50 values were much lower than the reference standard Baicalein. Enzyme inhibitory activities were also supported by computational docking results. Compounds 5c, 7a, 7b and 7c also showed low values of % hemolytic activity as well, showing that these molecules were not toxic, indicating that these molecules can be utilized as potential therapeutic agents against inflammatory ailments.

Synthesis, biological screening and molecular docking studies of some ethylated sulfonamides having 1,4-Benzodioxane moiety.

The presented study comprises the synthesis of a new series of ethylated sulfonamides in which 1,4-benzodioxane moiety has been incorporated. The reaction of 1,4-benzodioxane-6-amine (1) with ethane sulfonyl chloride (2) yielded N-(2,3-dihydrobenzo[1,4]dioxin-6-yl)ethanesulfonamide (3), which further on treatment with various alkyl/aralkyl halides, 4a-r, in N,Nꞌ-dimethylformamide (DMF) and in the presence of lithium hydride (LiH) acting as a weak base and catalyst; yielded derivatives of N-alkyl/aralkyl substituted N-(2,3-dihydrobenzo[1,4]dioxin-6-yl)ethanesulfonamides (5a-r). The characterization of these derivatives was carried out by different spectroscopic techniques like infra red, proton-NMR and mass spectrometry; then screened against various enzymes i.e. acetylcholinesterase, butyrylcholinesterase, lipoxygenase and α-glucosidase enzymes and five different bacterial strains. The synthesized compounds were found to be good inhibitors of lipoxygenase but moderate inhibitors of AChE, BChE and α-glucosidase; whereas compounds 3, 5a, 5f, 5n and 5r were found good antibacterial compounds. The interaction between inhibitors and target enzymes (cholinestrases and lipoxygenase) was computationally observed which correlated with the experimental results.

Thiadiazine thione derivatives as anti-leishmanial agents: synthesis, biological evaluation, structure activity relationship, ADMET, molecular docking and molecular dynamics simulation studies.

During last decades, 3,5-disubstituted-tetrahydro-2H-thiadiazine-2-thione scaffold remains the center of interest due to their ease of preparation, diverse range substituents at N-3 and N-5 positions, and profound biological activities. In the current study, a series of 3,5-disubstituted-tetrahydro-2H-thiadiazine-2-thiones were synthesized in good to excellent yield, and the structure of the compounds were confirmed by various spectroscopic techniques such as FTIR, 1H-NMR, 13C-NMR and Mass spectrometry, and finally evaluated against Leishmania major. Whereas, all the evaluated compounds (1-33), demonstrate potential leishmanicidal activities with IC50 values in the range of (1.30- 149.98 uM). Among the evaluated compounds such as 3, 4, 6, and 10 exhibited excellent leishmanicidal activities with IC50 values of (2.17 µM), (2.39 µM), (2.00 µM), and (1.39 µM), respectively even better than the standard amphotericin B (IC50 = 0.50) and pentamidine (IC50 = 7.52). In order to investigate binding interaction of the most active compounds, molecular docking study was conducted with Leishmania major. Further molecular dynamic simulation study was also carried out to assess the stability and correct binding of the most active compound 10, within active site of the Leishamania major. Likewise, the physiochemical properties, drug likeness, and ADMET of the most active compounds were investigated, it was found that none of the compounds violate Lipiniski's rule of five, which show that this class of compounds had enough potential to be used as drug candidate in near future.Communicated by Ramaswamy H. Sarma.

Synthesis and characterization of biologically active flurbiprofen amide derivatives as selective prostaglandin-endoperoxide synthase II inhibitors: In vivo anti-inflammatory activity and molecular docking.

A novel series of twenty two flurbiprofen amides (1-22) were designed and synthesized in good to excellent yields by reacting flurbiprofen acid with various aromatic/aliphatic primary amines in the presence of 1,1­carbonyldiimidazole (CDI) in basic medium using acetonitrile as solvent. Structures of the synthesized derivatives were elucidated with the help of HR-ESI-MS, 1H-, and 13C NMR spectroscopy and finally screened them for their in-vivo anti-inflammatory potential using carrageenan induced mice paw oedema assay. Among the series, four compounds (8, 14, 15, and 20) displayed excellent activity ranging from 59.0 to 77.7 % decrease, while eight compounds (1, 3, 7, 10, 12, 13, 17, and 18) exhibited good activity in the decrease range of 37.0-50.0 %. Additionally, four compounds (2, 6, 16, and 22) attributed less activity, while the remaining six compounds (4, 5, 9, 11, 19, and 21) were found to be inactive. Furthermore, the In-silico studies were executed on the synthesized derivatives in order to explain the binding interface of compounds with the active sites of prostaglandin endoperoxide-synthase II enzyme.

Inhibition of Acetylcholinesterase with Novel 1, 3, 4, Oxadiazole Derivatives: A Kinetic, In Silico, and In Vitro Approach.

Alzheimer's disease (AD) is a neurological disease that disturbs the memory, thinking skills, and behavior of the affected person. AD is a complex disease caused by the breakdown of acetylcholine via acetylcholinesterase (AChE). The present study aimed to assess the synthetic inhibitors of AChE that could be used to treat AD. For this purpose, synthetic compounds of oxadiazole derivatives (15-35) were evaluated and identified as promising inhibitors of AChE, exhibiting IC50 varying between 41.87 ± 0.67 and 1580.25 ± 0.7 µM. The kinetic parameters indicated that all the studied compounds bind to the allosteric site and decrease the efficiency of the AChE enzyme. In silico docking analysis showed that the majority of the compounds interact with the anionic subsite and Per-Arnt-Sim domain of AChE and are stabilized by various bonds including π-π and hydrogen bonding. The stability of the most potent compounds 16 and 17 with AChE interaction was confirmed by molecular dynamics simulations. Moreover, all compounds exhibited concentration-dependent calcium (Ca2+) antagonistic and spasmolytic activities. Among the whole series of oxadiazole derivatives, compounds 16 and 17 displayed the highest activities on spontaneous and potassium (K+)-induced contraction. Therefore, the AChE inhibitory potential, cytotoxicity safe profile, and Ca2+ antagonistic ability of these compounds make them potential therapeutic agents against AD and its associated problems in the future.

2-Mercaptobenzimidazole clubbed hydrazone for Alzheimer's therapy: In vitro, kinetic, in silico, and in vivo potentials.

Alzheimer's is a type of dementia that affects the affected person's thinking, memory, and behavior. It is a multifactorial disease, developed by the breakdown of the neurotransmitter acetylcholine via acetylcholinesterase (AChE). The present study was designed to evaluate potential inhibitors of acetylcholinesterase that could be used as a therapeutic agent against Alzheimer's disease (AD). For this course, synthetic compounds of the Schiff bases class of 2-mercaptobenzimidazole hydrazone derivatives (9-14) were determined to be potent acetylcholinesterase inhibitors with IC50 values varying between 37.64 ± 0.2 and 74.76 ± 0.3 µM. The kinetic studies showed that these are non-competitive inhibitors of AChE. Molecular docking studies revealed that all compounds accommodate well in the active site and are stabilized by hydrophobic interactions and hydrogen bonding. Molecular dynamics (MD) simulations of selected potent inhibitors confirm their stability in the active site of the enzyme. Moreover, all compounds showed antispasmodic and Ca2+ antagonistic activities. Among the selected compounds of 2-mercaptobenzimidazole hydrazone derivatives, compound 11 exhibited the highest activity on spontaneous and K+-induced contractions, followed by compound 13. Therefore, the Ca2+ antagonistic, AChE inhibition potential, and safety profile of these compounds in the human neutrophil viability assay make them potential drug candidates against AD in the future.

Phytohormones Producing Acinetobacter bouvetii P1 Mitigates Chromate Stress in Sunflower by Provoking Host Antioxidant Response.

Different physical and chemical techniques are used for the decontamination of Cr+6 contaminated sites. The techniques are expensive, laborious, and time-consuming. However, remediation of Cr+6 by microbes is viable, efficient, and cost-effective. In this context, plant growth-promoting rhizobacteria Acinetobacter bouvetii P1 isolated from the industrial zone was tested for its role in relieving Cr+6 induced oxidative stress in sunflower. At the elevated Cr+6 levels and in the absence of P1, the growth of the sunflower plants was inhibited. In contrast, the selected strain P1 restored the sunflower growth under Cr+6 through plant growth-promoting interactions. Specifically, P1 biotransformed the Cr+6 into a stable and less toxic Cr+3 form, thus avoiding the possibility of phytotoxicity. On the one hand, the P1 strengthened the host antioxidant system by triggering higher production of enzymatic antioxidants, including catalases, ascorbate peroxidase, superoxide dismutase, and peroxidase. Similarly, P1 also promoted higher production of nonenzymatic antioxidants, such as flavonoids, phenolics, proline, and glutathione. Apart from the bioremediation, P1 solubilized phosphate and produced indole acetic acid, gibberellic acid, and salicylic acid. The production of phytohormones not only helped the host plant growth but also mitigated the harsh condition posed by the elevated levels of Cr+6. The findings mentioned above suggest that P1 may serve as an excellent phyto-stimulant and bio-remediator in a heavy metal-contaminated environment.

New diterpenoid alkaloids from Aconitum heterophyllum Wall: Selective butyrylcholinestrase inhibitors.

Two new diterpenoid alkaloids, heterophyllinine-A (1) and heterophyllinine-B (2), along with two known alkaloids dihydroatisine (3) and lycoctonine (4) were isolated from the roots of Aconitum heterophyllum Wall. The structure of (1) and (2), were deduced on the basis of spectral data. Compounds 1-2 inhibited acetylcholinesterase (AChE, EC 3.1.1.7) and butyrylcholinesterase (BChE, EC 3.1.1.8) enzymes in a concentration-dependent manner with percent inhibition ranging between 4.24% and 6.94 % and 79.1 % and 82.75 % for AChE and BChE, respectively indicating that compounds 1 and 2 are about thirteen times more specific to BChE than AChE.

Design, Synthesis, Biological Evaluation and Molecular Docking Studies of Some New Sulfonamides Possessing 1,4-Benzodioxane Nucleus.

In the current research work we have reported a series of N-aryl-2,3-dihydrobenzo[1,4]dioxine-6-sulfonamides 3 and their N-substituted derivatives 6 and 7, obtained from 3 with benzyl chloride and ethyl iodide, respectively. The synthesis was accomplished as a multistep sequence. The structural confirmations were established by 1H NMR, IR and EIMS spectral techniques. Butyrylcholinesterase (BChE), acetylcholinesterase (AChE) and lipoxygenase (LOX) enzymes were used in this study. It was observed that most of the compounds prepared exhibit a moderate activity against BChE and AChE but promisingly good activity against lipoxygenase. Among the parent sulfonamides 3a, 3b, 3c and 3e showed the proficient antimicrobial activities, while from the derivatives 6a, 6c, 7a, 7b and 7c were found active against the selected panel of bacterial and fungal species. Hemolytic activity was also conducted to check their therapeutic utility. All the compounds were computationally docked against LOX, BChE and AChE enzymes.

Urease and serine protease inhibitory alkaloids from Isatis tinctoria.

Phytochemical investigations on the alkaloidal fraction of the whole plant of the Isatis tinctoria led to the isolation of the alkaloids 1-6., 3'-Hydroxyepiglucoisatisin (3), Epiglucoisatisin (2) were found to be potent urease inhibitors in a concentration-dependent manner with IC(50) values 25.63 +/- 0.74, 37.01 +/- 0.41 and 31.72 +/- 0.93, 47.33 +/- 0.31 microM against Bacillus pasteurii & Jack bean urease, respectively. Compounds 3 and 2 also showed potent inhibitory potential against alpha-chymotrypsin with IC(50) values of 23.40 +/- 0.21 and 27.45 +/- 0.23 microM, respectively.

Two new protease-inhibiting glycosphingolipids from Buddleja crispa.

Crispins A (1) and B (2), two new glycosphingolipids, were isolated from the whole plant Buddleja crispa, along with three known compounds: alpha-amyrin, linoleic acid, and stigmasterol. Their structures were elucidated by chemical and spectroscopic techniques. Both 1 and 2 showed significant inhibitory activity against alpha-chymotrypsin in a concentration-dependent manner.

Chemistry, urease inhibition, and phytotoxic studies of binuclear vanadium(IV) complexes.

Vanadium plays an important role in biological systems and exhibits a variety of bioactivities. In an effort to uncover the chemistry and biochemistry of vanadium with nitrogen- and oxygen-containing ligands, we report herein the synthesis and spectroscopic characterization of vanadium(IV) complexes with hydrazide ligands. Substituents on these ligands exhibit systematic variations of electronic and steric factors. Elemental and spectral data indicate the presence of a dimeric unit with two vanadium(IV) ions coordinated with two hydrazide ligands along with two H(2)O molecules. The stability studies of these complexes over time in coordinating solvent, DMSO, indicates binding of the solvent molecules to give [V2O2L2(H2O)2(DMSO)2]2+ (L=hydrazide ligand) and then conversion of it to a monomeric intermediate species, [VOL(DMSO)3]1+. Hydrazide ligands are inactive against urease, whereas vanadium(IV) complexes of these ligands show significant inhibitory potential against this enzyme and are found to be non-competitive inhibitors. These complexes also show low phytotoxicity indicating their usefulness for soil ureases. Structure-activity relationship studies indicate that the steric and/or electronic effects that may change the geometry of the complexes play an important role in their inhibitory potential and phytotoxicity.

Kinetics studies on triacontanyl palmitate: a urease inhibitor.

The mechanism of inhibition of jack bean and Bacillus pasteurii ureases was investigated by triacontanyl palmitate (1) which is a long-chain fatty ester and has been isolated from Symplocos racemosa Roxb. Lineweaver-Burk, Dixon plots, and their secondary replots showed that 1 is a non-competitive inhibitor of these enzymes. K(i) values were found to be 60.03 +/- 1.72 and 88.23 +/- 0.31 microM against jack bean and B. pasteurii ureases, respectively.

Chymotrypsin inhibitory constituents from Haloxylon recurvum.

Haloxylase, the triglyceride (1), unsaturated fatty acid (2), and saturated fatty acid methyl ester (3) have been isolated from the chloroform-soluble fraction of Haloxylon recurvum. Their structures have been elucidated through spectroscopic studies and chemical transformation. All these compounds showed significant inhibitory activity against the enzyme chymotrypsin in a concentration dependent fashion.