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Phytochemical investigation of Platytaenia multicaule resulted in the isolation of two new ceramides, N -triacontylpentadecanamide (1) and 1,3,4-trihydroxy-2,dodecanoylamino-(24 E )-unacotenene (2), along with two known compounds, β-sitosterol (3) and β-sitosterol glycoside (4). The structure elucidation of the isolated compounds was based primarily on 1D and 2D NMR analyses, including COSY, NOESY, HMQC, and HMBC correlations. [ABSTRACT FROM AUTHOR]

Three new sesquiterpene hemiacetals, tentatively named as achilleanone ( 1 ), vermiculone ( 2 ) and vermicularone ( 3 ) have been isolated from Achillea vermicularis , along with three other known compounds ß-amyrin, oleonolic acid and ß-sitosterol. The structure elucidation of new compounds was based primarily on two-dimensional (2D) NMR techniques including Nuclear Overhauser Effect/Enhancement (NOE), heteronuclear multiple quantum coherence (HMQC), heteronuclear multiple bond correlation (HMBC) and nuclear overhauser effect spectroscopy (NOESY) experiments. Compounds 1 , 2 and 3 have displayed inhibitory potential against lipoxygenase enzyme in a concentration-dependent fashion with promising IC50 values. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of Symplocos racemosa resulted in the isolation of a new ethyl substituted glycoside, 1-ethyl brachiose-3'-acetate ( 1 ) along with four known compounds ketochaulmoogric acid ( 2 ), nonaeicosanol ( 3 ), triacontyl palmitate ( 4 ) and methyl triacontanoate ( 5 ). The substitution of ethyl group on 1 was natural because during the course of extraction and purification ethanol was not used. The structural elucidation of the isolated compounds was based primarily on 1D- and 2D-NMR analysis, including COSY, HMQC, and HMBC correlations. The glycoside 1 and triacontyl palmitate ( 4 ) displayed the inhibitory potential against lipoxygenase and urease enzyme, respectively. [ABSTRACT FROM AUTHOR]

Dimethylphenylamines, 4-chlorobutanoyl chloride, Structure characterization, Antibacterial, Hemolytic activity. [Extracted from the article]

• Butanamides compounds were synthesized for the treatment of melanogenesis. • The inhibitory activity of synthesized compounds were evaluated against tyrosinase. • The compounds were evaluated as an antimelanogenesis using zebrafish. • The cytotoxicity of these butanamides was also screened using hemolytic activity. • In silico study was performed to check the binding profile against tyrosinase. In the current research work, different N -(substituted-phenyl)-4-{(4-[(E)-3-phenyl-2-propenyl]-1-piperazinyl}butanamides have been synthesized according to the protocol described in scheme 1. The synthesis was initiated by reacting various substituted anilines (1a-e) with 4-chlorobutanoyl chloride (2) in aqueous basic medium to give various electrophiles, 4-chloro- N -(substituted-phenyl)butanamides (3a-e). These electrophiles were then coupled with 1-[(E)-3-phenyl-2-propenyl]piperazine (4) in polar aprotic medium to attain the targeted N -(substituted-phenyl)-4-{(4-[(E)-3-phenyl-2-propenyl]-1-piperazinyl}butanamides (5a-e). The structures of all derivatives were identified and characterized by proton-nuclear magnetic resonance (1H NMR), carbon-nuclear magnetic resonance (13C NMR) and Infra-Red (IR) spectral data along with CHN analysis. The in vitro inhibitory potential of these butanamides was evaluated against Mushroom tyrosinase, whereby all compounds were found to be biologically active. Among them, 5b exhibited highest inhibitory potential with IC 50 value of 0.013 ± 0.001 µM. The same compound 5b was also assayed through in vivo approach, and it was explored that it significantly reduced the pigments in zebrafish. The in silico studies were also in agreement with aforesaid results. Moreover, these molecules were profiled for their cytotoxicity through hemolytic activity, and it was found that except 5e , all other compounds showed minimal toxicity. The compound 5a also exhibited comparable results. Hence, some of these compounds might be worthy candidates for the formulation and development of depigmentation drugs with minimum side effects. [ABSTRACT FROM AUTHOR]

• Sulfonamide derivatives were synthesized as therapeutic agents to target the Alzheimer's disease. • The inhibitory potential of newly synthesized compounds were evaluated against butyrylcholinesterase (BChE). • The cytotoxicity of these sulfonamides was also ascertained through hemolysis of bovine red blood cells. • Computational analysis was performed to check their binding profile against target protein. In the designed research work, a series of 2-furoyl piperazine based sulfonamide derivatives were synthesized as therapeutic agents to target the Alzheimer's disease. The structures of the newly synthesized compounds were characterized through spectral analysis and their inhibitory potential was evaluated against butyrylcholinesterase (BChE). The cytotoxicity of these sulfonamides was also ascertained through hemolysis of bovine red blood cells. Furthermore, compounds were inspected by Lipinki Rule and their binding profiles against BChE were discerned by molecular docking. The protein fluctuations in docking complexes were recognized by dynamic simulation. From our in vitro and in silico results 5c , 5j and 5k were identified as promising lead compounds for the treatment of targeted disease. [ABSTRACT FROM AUTHOR]

Highlights from the article: (C=O str.), 1587 (C=C aromatic str.), 1435 (S=O), (C=O str.), 1579 (C=C aromatic str.), 1432 (S=O), (C=O str.), 1588 (C=C aromatic str.), 1438 (S=O), (C=O str.), 1577 (C=C aromatic str.), 1439 (S=O), (C=O str.), 1587 (C=C aromatic str.), 1431 (S=O).

Purpose: To study the antibacterial activity of various sulfonamides derived from 1,3-benzodioxol-5-carbohydrazide. Methods: The synthesis involved the conversion of 1,3-benzodioxol-5-carboxylic acid (1) to ethyl 1,3-benzodioxol-5-carboxylate (2) and then to 1,3-benzodioxol-5-carbohydrazide (3). The target molecules, 2-(1,3-benzodioxol-5-ylcarbonyl)arylsulfonohydrazide derivatives (5a-l) were synthesized through a benignant method from aqueous medium by the reaction of 3 and arylsulfonyl chlorides (4a-l). The structural formulae of the synthesized compounds were characterized by infra red spectroscopy (IR), proton nuclear magnetic resonance (1H-NMR) and electron impact mass spectrometry (EI-MS). The compounds were screened for in vitro antibacterial activity by determining their minimum inhibitory concentration (MIC). Results: The molecule, 5k, bearing 2-hydroxy-3,5-dichlorophenyl group exhibited the highest activity with MIC of 11.92 ± 3.40 (S. typhi), 8.37 ± 2.22 (E. coli), 9.28 ± 2.31 (P. aeroginosa), 11.76 ± 1.30 (B. subtilis) and 10.30 ± 1.63 (S. aureus) ymoles/L relative to that of ciprofloxacin with 9.42 ± 1.09, 8.02 ± 2.17, 8.11 ± 1.32, 8.88 ± 2.00 and 9.23 ± 1.87 ymoles/L respectively. Conclusion: The most potent of the synthesized compounds (5k) posesses moderate activity against all the bacterial strains, while 5g remained completely inactive. [ABSTRACT FROM AUTHOR]

The present study aimed at the evaluation of anti-hyperglycemic and hepatoprotective potential of a new drug candidate, 5-[(4-chlorophenoxy) methyl]-1,3,4-oxadiazole-2-thiol (OXCPM) through in vitro and in vivo assays, respectively. The compound displayed excellent dose-dependent α-amylase (28.0-92.0%), α-glucosidase (40.3-93.1%) and hemoglobin glycosylation (9.0%- 54.9%) inhibitory effects and promoted the uptake of glucose by the yeast cells (0.2 to 26.3%). The treatment of the isoniazid- and rifampicin- (p.o., 50 mg/kg of each) intoxicated rats with OXCPM (100 mg/kg, p.o.) resulted in restoring the normal serum levels of the non-enzymatic (total bilirubin, total protein and albumin) and bringing about a remarkable decrease in the levels of enzymatic (alanine transaminases, aspartate transaminases and alkaline phosphatase) biomarkers. The molecular docking studies indicated high binding affinity of the compound for hyperglycemia-related protein targets; fructose-1,6-bisphosphatase, beta2-adrenergic receptors and glucokinase. The results indicate that OXCPM may not only reduce hyperglycemia by enzyme inhibition but also the disease complications through protection of hemoglobin glycosylation and hepatic injury. [ABSTRACT FROM AUTHOR]

Biological screening combined with the synthesis of heterocyclic compounds with numerous functions is the most effective approach available for pharmacological assessment. In the  under taken research that is presented here,  4-(1H-indol-3-yl)butanoic acid was sequentially converted into 4-(1H-indol-3-yl)butanoate, 4-(1H-indol-3-yl)butanohydrazide and 5-[3-(1H-indol-3-yl)propyl]-1,2,4-triazole-2-thiol  as a nucleophile. The structural confirmation of all the synthesized compounds was done by IR, 1H-NMR, 13C-NMR and CHN analysis data. The enzyme inhibitory effects of these bi-heterocyclic propanamides were evaluated against elastase, and Oleanolic acid with IC50 value 13.453 ± 0.015 µM was used as a standard.  The kinetics mechanism was ascribed by Lineweaver-Burk plots, which revealed that compound 9d inhibited elastase competitively. The inhibition constant Ki calculated from Dixon plots for this compound was 0.51 μM. Compound 9d's activity (IC50 = 0.142 ± 0.014 µM) significantly increased when a slightly bulky ethyl group was replaced for the solitary methyl group in 9c at the para position. However, compound 9e's activity was significantly lower (IC50 = 38.338 ± 0.993µM). These molecules also exhibited mild cytotoxicity. So, these molecules might be deliberated as nontoxic medicinal scaffolds for dealing with the elastase related ailments such as lungs diseases, cyclic neutropenia, pruritic skin disease and liver infection., (© 2024 Wiley‐VCH GmbH.)

Considering the varied pharmacological prominence of thiazole and oxadiazole heterocyclic moieties, a unique series of bi-heterocyclic hybrids, 8a-h, was synthesized in a convergent manner. The structures of newly synthesized compounds were characterized by 1 H-NMR, 13 C-NMR, and IR spectral studies. The structure-activity relationship of these compounds was predicted by examining their inhibitory effects against alkaline phosphatase, whereby all these molecules exhibited superb inhibitory potentials relative to the standard used. The kinetics mechanism was determined by Lineweaver-Burk plots which revealed that 8g inhibited the studied enzyme non-competitively by forming an enzyme-inhibitor complex. The inhibition constant K i calculated from Dixon plots for this compound was 0.42 μM. The allosteric computational study was coherent with the experimental records and these ligands exhibited good binding energy values (kcal mol -1 ). The hemolytic analysis revealed their mild cytotoxicity towards red blood cell membranes and hence, these molecules have potential to be nontoxic medicinal scaffolds for the treatment of alkaline phosphate-associated ailments., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Considering the diversified pharmacological importance of thiazole and triazole heterocyclic moieties, a unique series of S -aralkylated bi-heterocyclic hybrids, 7a-l , was synthesized in a convergent manner. The structures of newly synthesized compounds were characterized by 1 H-NMR, 13 C-NMR, IR, and EI-MS spectral studies. The structure-activity relationship of these compounds was envisaged by analyzing their inhibitory effects against tyrosinase, whereby all these molecules exhibited potent inhibitory potentials relative to the standard used. The Kinetics mechanism was ascertained by Lineweaver-Burk plots, which revealed that 7g inhibited tyrosinase non-competitively by forming an enzyme-inhibitor complex. The inhibition constants K i calculated from Dixon plots for this compound was 0.0057µM. These bi-heterocyclic molecules also disclosed good binding energy values (kca l / mol) when assessed computationally. So, these molecules can be considered promising medicinal scaffolds for the treatment of skin disorders.

The synthesis of a novel series of bi-heterocyclic propanamides, 7a-l , was accomplished by S -substitution of 5-[(2-amino-1,3-thiazol-4-yl)methyl]-1,3,4-oxadiazol-2-thiol ( 3 ). The synthesis was initiated from ethyl 2-(2-amino-1,3-thiazol-4-yl)acetate ( 1 ) which was converted to corresponding hydrazide, 2 , by hydrazine hydrate in methanol. The refluxing of hydrazide, 2 , with carbon disulfide in basic medium, resulted in 5-[(2-amino-1,3-thiazol-4-yl)methyl]-1,3,4-oxadiazol-2-thiol ( 3 ). A series of electrophiles, 6a-l , was synthesized by stirring un/substituted anilines ( 4a-l ) with 3-bromopropanoyl chloride ( 5 ) in a basic aqueous medium. Finally, the targeted compounds, 7a-l , were acquired by stirring 3 with newly synthesized electrophiles, 6a-l , in DMF using LiH as a base and an activator. The structures of these bi-heterocyclic propanamides were confirmed through spectroscopic techniques, such as IR, 1 H-NMR, 13 C-NMR, and EI-MS. These molecules were tested for their urease inhibitory potential, whereby, the whole series exhibited very promising activity against this enzyme. Their cytotoxic behavior was ascertained through hemolysis and it was observed that all these were less cytotoxic agents. The in-silico molecular docking analysis of these molecules was also in full agreement with their in-vitro enzyme inhibition data.

In the presented work, 2,3-dihydro-1,4-benzodioxin-6-amine (1) was reacted with 4-chlorobenzenesulfonyl chloride (2) in presence of aqueous basic aqueous medium to obtain 4-chloro-N-(2,3-dihydro-1,4-benzodioxin-6-yl)benzenesulfonamide (3). In parallel, various un/substituted anilines (4a-l) were treated with bromoacetyl bromide (5) in basified aqueous medium to obtain corresponding 2-bromo-N-(un/substituted)phenylacetamides (6a-l) as electrophiles. Then the compound 3 was finally reacted with these electrophiles, 6a-l, in dimethylformamide (DMF) as solvent and lithium hydride as base and activator to synthesize a variety of 2-[[(4-chlorophenyl)sulfonyl](2,3-dihydro-1,4-benzodioxin-6-yl)amino]-N-(un/substituted)phenylacetamides (7a-l). The synthesized compounds were corroborated by IR, 1 H-NMR and EI-MS spectral data for structural confirmations. These molecules were then evaluated for their antimicrobial and antifungal activities along with their %age hemolytic activity. Some compounds were found to have suitable antibacterial and antifungal potential, especially the compound 2-[[(4-chlorophenyl)sulfonyl](2,3-dihydro-1,4-benzodioxin-6-yl)amino]-N-(3,5-dimethylphenyl)acetamide (7l) exhibited good antimicrobial potential with low value of % hemolytic activity.

A series of propanamide compounds 6a-l was derived by N-substitution reactions, encompassing tosyl, piperidine and 1,3,4-oxadiazole moieties. The intended array of compounds 6a-l was afforded by a series of five steps reaction scheme. 1-Tosylpiperidin-4-carboxylate (1) was synthesized by the reaction of tosyl chloride (a) with ethyl isonipecotate (b) under mild basic conditions. Compound 1 was subjected to nucleophillic substitution by hydrazine to synthesize 1-tosylpiperidin-4-carbohydrazide (2). The compound, 5-(1-tosylpiperidin-4-yl)-1,3,4-oxadiazole-2-thiol (3) was synthesized by intermolecular cyclization of compound 2 by CS2 under strong basic conditions. The target compounds, 6a-l, were finally synthesized from 3 by reacting with different electrophiles, 5a-l, in an aprotic polar solvent with sodium hydride as an activator. The different propanamoyl electrophiles, 5a-l, were synthesized by the reaction of different aromatic and aliphatic amines, 4a-l, with 3-bromopropionyl chloride under mild basic conditions. The structural elucidation was carried out using modern spectroscopic techniques including IR, 1H-NMR and EI-MS. The antibacterial potential of synthesized compounds was assessed against five bacterial strains. Compounds 6a, 6c, 6d, 6e and 6f were found to be potent antibacterial agents.

The present study comprises the synthesis of a new series of benzenesulfonamides derived from N-sulfonation of 2-(4-methoxyphenyl)-1-ethanamine (1). The synthesis was initiated by the reaction of 2-(4-methoxyphenyl)-1-ethanamine (1) with benzenesulfonyl chloride (2), to yield N-(4-methoxyphenethyl)benzenesulfonamide (3). This parent molecule 3 was subsequently treated with various alkyl/aralkyl halides (4a-j) in N,N-dimethylformamide (DMF) and in the presence of a weak base lithium hydride (LiH) to obtain various N-(alkyl/aralkyl)-N-(4-methoxyphenethyl) benzenesulfonamides (5a-j). The characterization of these derivatives was carried out by spectroscopic techniques like IR, 1 H-NMR, and 13 C-NMR. Elemental analysis also supported this data. The biofilm inhibitory action of all the synthesized compounds was carried out on Escherichia coli and some of the compounds were identified to be very suitable inhibitors of this bacterial strain. Furthermore, the molecules were also tested for their cytotoxicity behavior to assess their utility as less cytotoxic therapeutic agents.

Heterocyclic chemistry is an important field of organic chemistry due to therapeutic potential. The minor modification in the structure of poly-functional compounds has great effect on therapeutic ability. In the presented research work, substituted 1,3,4-oxadiazole derivatives, 8a-p, have been synthesized by the reaction of 1-(4-bromomethylbenzenesulfonyl)-3-methylpiperidine (7) and 5-substituted-1,3,4-oxadiazole-2-thiol (4a-p). The 5-substituted-1,3,4-oxadiazole-2-thiol were synthesized by converting carboxylic acids correspondingly into esters, hydrazides and oxadiazoles. Secondly the electrophile, 1-(4-Bromomethylbenzenesulfonyl)-3-methylpiperidine (7), was prepared by the reaction of 3-methylpiperidine with 4-bromomethylbenzenesulfonyl chloride in the presence of water and Na 2 CO 3 under pH of 9-10. The compounds were structurally corroborated through spectroscopic data analysis of IR, EI-MS and 1H-NMR. The screening for antibacterial activity revealed the compounds to be moderate to excellent inhibitors against bacteria under study. Anti-enzymatic activity was assessed against urease enzyme and 1-{[4-({[5-(3-nitrophenyl)-1,3,4-oxadiazol-2-yl]sulfanyl}methyl)phenyl]sulfonyl}-3-methylpiperidine (8d) was the most active one.

The present investigation was undertaken to evaluate the antibacterial, antifungal and hemolytic activities of organic and aqueous fractions of Fumaria indica, Dicliptera bupleuroides and Curcuma zedoaria. The methanolic extracts of the plants were dissolved in the water (distilled) separately and then partitioned with the n-hexane, CHCl3, EtOAc and n-BuOH sequentially. Antibacterial activity was checked against Escherichia coli, Pasturella multocida, Bacillus subtilis and Staphylococcus aureus by the disc diffusion method using streptomycin sulphate, a standard antibiotic, as positive control. Antifungal activity was studied against four fungi i.e. Aspergillus niger, Aspergillus flavus, Ganoderma lucidum and Alternaria alternata by the disc diffusion method using fluconazole, a standard antifungal drug, as positive control. It was revealed that aqueous fraction of F. indica showed very good antibacterial activity against P. multocida with zone of inhibition 26mm and MIC of 98μg/mL. Its CHCl3 and n-BuOH fractions also displayed good results. Its CHCl3 fraction showed good antifungal activity against G. lucidum with zone of inhibition 24mm and MIC of 115μg/mL. Other polar fractions of F. indica showed good activity against somefungal strains. The CHCl3 and EtOAc fractions of D. bupleuroides displayed good antibacterial activity against some bacterial strains. Its EtOAc fraction showed good antifungal activity only against G. lucidum. The CHCl 3 fraction of C. zedoaria showed good activity against all studied bacterial strains, while its EtOAc and n-BuOH fractions displayed good results against some bacterial strains. None of the fractions of C. zedoaria displayed antifungal activity against the under test strains. All the studied fractions of three plants showed very less toxicity except n-hexane fraction of D. bupleuroides which showed 79% toxicity.

A new series of multifunctional amides has been synthesized having moderate enzyme inhibitory potentials and mild cytotoxicity. 2-Furyl(1-piperazinyl)methanone (1) was coupled with 3,5-dichloro-2-hydroxybenzenesulfonyl chloride (2) to form {4-[(3,5-dichloro-2-hydroxyphenyl)sulfonyl]-1-piperazinyl}(2-furyl)methanone (3). Different elecrophiles were synthesized by the reaction of various un/substituted anilines (4a-o) with 2-bromoacetylbromide (5), 2‑bromo‑N-(un/substituted-phenyl)acetamides (6a-o). Further, equimolar ratios of 3 and 6a-o were allowed to react in the presence of K 2 CO 3 in acetonitrile to form desired multifunctional amides (7a-o). The structural confirmation of all the synthesized compounds was carried out by their EI-MS, IR, 1 H NMR and 13 C NMR spectral data. Enzyme inhibition activity was performed against acetyl and butyrylcholinestrase enzymes, whereby 7e showed very good activity having IC 50 value of 5.54 ± 0.03 and 9.15 ± 0.01 μM, respectively, relative to eserine, a reference standard. Hemolytic activity of the molecules was checked to asertain their cytotoxicity towards red blood cell membrance and it was observed that most of the compounds were not toxic up to certain range. Moreover, chemoinformatic protepties and docking simulation results also showed the significance of 7e as compared to other compounds. Based on in vitro and in silico analysis 7e could be used as a template for the development of new drugs against Alzheimer's disease., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Microwave and conventional techniques were employed to synthesize a novel array of compounds 7a-g with 1,2,4-triazole and piperidine rings having great biological importance. The microwave assisted method has a better operational scope with respect to time and yield comparative to the conventional method. 1H-NMR, 13C-NMR and IR techniques were employed to justify the structure of synthesized compounds. The antioxidant, butyrylcholinesterase inhibition and urease inhibition potential of every synthesized compound was evaluated. Every member of the synthesized series was found potent against mentioned activities. Compound 7g was the most active anti-urease agent having IC50 (μM) value 16.5±0.09 even better than the thiourea with an IC50(μM) value of 24.3±0.24. The better urease inhibition potential of 7g was also elaborated and explained by docking and bovine serum albumin (BSA) binding studies.

A number of novel 5-substituted-2-((6-bromo-3,4-methylenedioxybenzyl)thio)-1,3,4-Oxadiazole derivatives (6a-l) have been synthesized to evaluate their antibacterial activity. Using aryl/aralkyl carboxylic acids (1a-l) as precursors, 5-substituted-1,3,4-Oxadiazol-2-thiols (4a-l) were yielded in good amounts. The derivatives, 4a-l, were subjected to electrophilic substitution reaction on stirring with 6-bromo-3,4-methylenedioxybenzyl chloride (5) in DMF to synthesize the required compounds. All the synthesized molecules were well characterized by IR, 1 H-NMR, 13 C-NMR and EIMS spectral data and evaluated for antibacterial activity against some bacterial strains of Gram-bacteria. The molecule, 6d, demonstrated the best activity among all the synthesized molecules exhibiting weak to moderate inhibition potential.

N-(Substituted)-5-(1-(4-methoxyphenylsulfonyl)piperidin-4-yl)-4H-1,2,4-triazol-3-ylthio) acetamide were synthesized by following conventional as well as microwave assisted protocol through five consecutive steps under the impact of various reaction conditions to control the reaction time and the yield of product. Starting from 4-methoxybenzenesulfonyl chloride and ethyl isonipecotate, product 3 was obtained which was converted into product 4 by treating with hydrazine hydrate. In step 3, the product 4 was refluxed with methyl isothiocyanate and KOH to yield compound 5 which was finally treated with variety of N-substituted acetamides to yield an array of different new compounds (8a-k). These synthesized compounds were evaluated for their inhibition potential against bovine carbonic anhydrase (bCA-II), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Compound 8g demonstrated good activity against bCA-II, AChE and BChE with IC 50 values of 8.69 ± 0.38 μM, 11.87±0.19 μM and 26.01±0.55 μM respectively. SAR studies assisted with molecular docking were carried out to explore the mode of binding of the compounds against the studied enzymes.

The various p-substituted benzenesulfonyl chlorides (2a-e) were treated with (3,4-methylenedioxy) benzylamine (1) in the presence of aqueous Na 2 CO 3 solution to synthesize N-(3,4-methylenedioxybenzyl)-4-substitutedbenzenesulfonamides (3a-e). The synthesized molecules were further converted into corresponding N-ethyl/benzyl/4-flourobenzyl-N-(3,4-methylenedioxybenzyl)-4-substitutedbenzenesulfonamides (7a-e, 8a-e, 9a-e) on reaction with ethyl iodide (4), benzyl chloride (5) and 4-flourobenzyl chloride (6) in the presence of sodium hydride using N,N-dimethylformamide as solvent. The structure elucidation was processed through different spectral techniques including IR, 1 H-NMR and EIMS. The screening of the synthesized molecules against Gram-bacterial strains, to evaluate antibacterial activity, showed them moderately good inhibitors as shown by their low MIC values.

New potent organic compounds were synthesized with an aim of good biological activities such as antibacterial and anti-enzymatic. Three series of sulfonamide derivatives were synthesized by treating N-alkyl/aryl substituted amines (2a-f) with 4-chlorobenzensulfonyl chloride (1) to yield N-alkyl/aryl-4-chlorobenzenesulfonamide(3af) that was then derivatized by gearing up with ethyl iodide (4), benzyl chloride (5) and 4-chlorobenzyl chloride (6) using sodium hydride as base to initialize the reaction in a polar aprotic solvent (DMF) to synthesize the derivatives, 7a-f, 8af and 9a-f respectively. Structure elucidation was brought about by IR, 1H-NMR and EIMS spectra for all the synthesized molecules which were evaluated for their antibacterial activities and inhibitory potentials for certain enzymes.

The biological potential of N'-substituted-2-(5-(3-chlorophenyl)-1,3,4-Oxadiazol-2-ylthio)acetohydrazide (8a-p) has been evaluated against bacterial strains of Gram-negative and Gram-positive bacteria. The multistep synthesis involved the conversion of 3-chlorobenzoic acid (1) to ethyl 3-chlorobenzoate (2), 3-chlorobenzohydrazide (3), 5-(3-chlorophenyl)-1,3,4-Oxadiazol-2-thiol (4), ethyl 2-(5-(3-chlorophenyl)-1,3,4-Oxadiazol-2-ylthio) acetate (5) and 2-(5-(3-chlorophenyl)-1,3,4-Oxadiazol-2-ylthio)acetohydrazide (6). The last step involved the reaction of 6 and aryl aldehydes, 7a-p, in methanol to synthesize the Schiff bases, 8a-p, with better yields. The structures of all the molecules were corroborated by spectral analysis. The Schiff bases were further evaluated for the antibacterial activity and found to be moderately good inhibitors of bacterial strains of Gram-bacteria.

A new series of N-substituted derivatives of 2-{(5-phenyl-1,3,4-Oxadiazol-2-yl)sulfanyl}acetamides was synthesized. The synthesis was carried out by converting benzoic acid (1) into ethyl benzoate (2), benzohydrazide (3) and then 5-pheny-1,3,4-Oxadiazol-2-thiol (4) step by st0ep. The target compounds 6a-p were synthesized by reaction of compound 4 with equimolar ratios of different N-alkyl/aryl substituted 2-bromoacetamide (5a-p) in the presence of DMF and sodium hydride (NaH). The spectral (EI-MS, IR, (1)H-NMR) characterization of all the synthesized compounds reveal their successful synthesis. The compounds were also screened for antimicrobial & hemolytic activity and most of them were found to be active against the selected microbial species at variable extent relative to reference standards. But 6h was the most active against the selected panel of microbes. This series showed less toxicity and may be considered for further biological screening and application trial except 6m, possessing higher cytotoxicity.

Sulfonamides are adherent to a biologically dynamic category of compounds and are under consideration of many organic synthetic researches to synthesize pharmacologically important compounds. In this demonstrated research work, a benignant series of chlorinated sulfonamides were synthesized and screened against different enzymes. These various chlorinated sulfonamides (3a-i) were set up by pairing of different substituted anilines (2a-i) with 4-chlorobenzenesulfonyl chloride (1) under basic pH in an aqueous media. The structures of the synthesized chlorinated sulfonamides were furnished by 1H-NMR, IR & EI-MS. The different enzymes used for the evaluation of bioactivity of all the synthesized compounds were urease, butyrylcholinesterase (BChE) and lipoxygenase (LOX). All the compounds exhibited good inhibitory activities against these enzymes but the strong activity was shown against BChE and hence can be employed for discovery of 'lead' compounds against Alzheimer's disease (AD).

A new series of N-aryl/aralkyl substitued-2"-[(phenylsulfonyl)(piperidin-1-yl)amino]acetamide (7a-k) was synthesized. These derivatives were geared up by the pairing of benzenesulfonyl chloride (4) with 1-aminopiperidine (5) under dynamic pH control in aqueous media to afford parent compound N-(Piperidin-1-yl) benzenesulfonamide (6), followed by the substitution at nitrogen atom with different electrophiles N-aryl/aralkyl-substituted-2-bromoacetamides (3a-k) in the presence of sodium hydride (NaH) and N,N-Dimethylformamide (DMF) to give a new series of N-substituted derivatives of acetamide (7a-k) bearing piperidine moiety. All the synthesized compounds were confirmed on the basis of IR, EIMS and (1)H-NMR spectral data. The synthesized compounds were evaluated against acetylcholinesterase and butyrylcholinesterase (AChE and BChE) respectively and lipoxygenase (LOX) enzymes. Almost all the synthesized compounds displayed promising activity but few of them remained inactive against lipoxygenase enzymes.

Coumarins have much importance in dyes, drugs, perfumes and pesticides. In the demonstrated research work, a benignant series of chlorinated coumarins was synthesized and screened against different enzymes. First, 6-Chloro-7-hydroxy-4-methyl-2H-chromen-2-one (3) was geared up by the reaction of 4-chlororesorcinol (1) and ethyl acetoacetate (2) in the presence of concentrated H(2)SO(4). Second, various O-substituted derivatives of chlorinated coumarins, 5a-j, were set up by pairing different alkyl/aralkyl halides, 4a-j, with 3 in the presence of NaH in DMF as solvent. The structures of all the synthesized compounds were clarified through spectral analysis using EI-MS, IR and (1)H-NMR. The different enzymes used for the evaluation of bioactivity of all the synthesized compounds were acetyl cholinesterase (AChE), butyryl cholinesterase (BChE) and lipoxygenase (LOX). The most proficient activity was shown against both cholinesterase enzymes.

In the current study, a series of 5-substituted-1,3,4-oxadiazole-2yl-N-(2-methoxy-5-chlorophenyl)-2-sulfanyl acetamide was synthesized by converting variously substituted/unsubstituted aromatic organic acids successively into the corresponding esters, hydrazides and then 5-substituted-1,3,4-oxadiazole-2-thiols. Finally the target compounds were obtained by stirring 5-substituted-1,3,4-oxadiazole-2-thiols with N-(2-methoxy-5-chlorophenyl)-2-bromoacetamide in the presence of N,N-dimethyl formamide (DMF) and sodium hydride (NaH). The structures of the synthesized compounds were confirmed based on (1)H-NMR, IR and mass spectral data. The synthesized compounds were screened against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and lipoxygenase enzymes (LOX) and were found to be relatively more active against acetyl cholinesterase.

The phytochemical investigation of the ethylacetate-soluble fraction of Caryopteris odorata (Ham. ex Roxb.) led to the isolation of four new iridoid glucosides (1-4): 8-O-trans-cinnamoyl caryoptoside (1), 8-O-trans-cinnamoyl shanzhiside methylester (2), 8-O-trans-cinnamoyl mussaenoside (3) and 8-O-cafeoyl massenoside (4). The structures of these compounds were determined by FAB-MS, IR, 1D and 2D-NMR spectroscopy and by comparing with the published data of the closely related compounds. The antioxidant potential of the isolated iridoids (1-4) was evaluated relative to conventionally used standards and these molecules exhibited good antioxidant potential. Moreover, their inhibitory potential was also screened against three enzymes, namely acetyl cholinesterase, butyrylcholinesterase and lipoxygenase. These iridoid glucosides were found to be inactive against acetyl and butyrylcholinesterases but active against lipoxygenase.

In the present study, a series of N-substituted derivatives of 2-phenylethylamine has been synthesized. The reaction of 2-phenylethylamine (1) with benzene sulfonyl chloride (2) yielded N-(2-phenylethyl) benzenesulfonamide (3), which further on treatment with alkyl/acyl halides (4a-i) in the presence of sodium hydride furnished into N-substituted sulfonamides (5a-i). These derivatives were characterized by IR, (1)H-NMR and EI-MS and then screened against acetyl cholinesterase (AChE), butyryl cholinesterase (BChE) and lipoxygenase enzyme (LOX) and were found to be potent inhibitors of butyryl cholinesterase only.

In the search of new trypsin inhibitors caffeic acid (1), cinnamic acid (2), gallic acid (3) and eugenol (4) from Cinnamomum zeylanicum, ferulic acid (5) from Impatiens bicolor, vanillin (6) from Melia azedarach and catechol (7) from Allium cepa were isolated through bioassay guided fractionation of the plant extracts. IC (50) values of the compounds 1, 2 and 5 were found to be 0.35 ± 0.02 mM, 0.96 ± 0.05 mM and 1.22 ± 0.06 mM, respectively. Lineweaver-Burk and Dixon plots and their secondary replots showed that 1 was non-competitive inhibitor of this enzyme with K(i) value 0.102 ± 0.006 mM.

The asymmetric unit of the title co-crystal, C(8)H(12)N(+)·C(7)H(4)NO(4) (-)·C(7)H(5)NO(4), contains two cations, two anions and two neutral 4-nitro-benzoic acid mol-ecules. In the crystal, O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds connect the ions and mol-ecules, forming a three-dimensional network.

In the title mol-ecule, C(11)H(17)NO(3)S, the S atom has a distorted tetra-hedral geometry [maximum deviation: O-S-O = 119.08 (9)°]. In the crystal, mol-ecules are connected by inter-molecular N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds, forming layers of mol-ecules aligned parallel to (110). The 2-methyl-propan-1-ol group of the mol-ecule is disordered over two positions with an 0.592 (4):0.408 (4) occupancy ratio.

In the title mol-ecule, C(10)H(15)NO(3)S, the S atom is bonded in a distorted tetra-hedral geometry. In the crystal structure, inter-molecular N-H⋯O, O-H⋯O and weak C-H⋯O hydrogen bonds connect the mol-ecules to form a two-dimensional network parallel to (100). The 2-methyl-propan-1-ol group is disordered over two orientations with occupancies of 0.570 (3) and 0.430 (3).

In the title mol-ecule, C(20)H(19)NO(3)S, the dihedral angle between the phenyl rings is 48.93 (18)°, and they make dihedral angles of 38.37 (17) and 86.50 (19)° with the benzene ring. A weak intra-molecular C-H⋯O inter-action might stabilize the mol-ecular conformation. In the crystal, weak π-π stacking inter-actions between the benzene rings [centroid-centroid distance = 3.774 (2) Å] may help to establish the packing.

In the title compound, C(13)H(12)ClNO(3)S, the dihedral angle between the two aromatic rings is 73.94 (9)°. An intra-molecular C-H⋯O hydrogen bond occurs. In the crystal, inter-molecular N-H⋯O hydrogen bonds connect the mol-ecules to centrosymmetric dimers, forming an R(2) (2)(8) ring motif. The packing is consolidated by C-H⋯O hydrogen bonds and weak π-π inter-actions [centroid-centroid distances = 3.81 (3) and 3.81 (3) Å].

The asymmetric unit of the title compound, C(13)H(13)NO(3)S, contains two crystallographically independent mol-ecules in which the dihedral angles between the phenyl and benzene rings are 88.16 (12) and 44.50 (12)°. One of the mol-ecules features an intra-molecular N-H⋯O hydrogen bond. In the crystal, the mol-ecules are linked into dimers by pairs of N-H⋯O hydrogen bonds. The dimers are further connected by C-H⋯O and C-H⋯π inter-actions, forming a three-dimensional network.

In the title mol-ecule, C(15)H(17)NO(3)S, the C-S-N-C(benzene) torsion angle is 81.45 (16)°, and the two aromatic rings form a dihedral angle of 45.83 (12)°. In the crystal structure, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into chains parallel to the b axis.

In the title mol-ecular salt, NH(4) (+)·C(10)H(14)BrO(4)S(-), the norbornane skeleton of the anion is composed of two five-membered rings in envelope conformations and a six-membered ring with one Br atom, one carbonyl O atom and a methyl group held in a boat conformation by a bridging methyl-ene group. Short intra-molecular C-H⋯O and C-H⋯Br inter-actions occur. In the crystal, the component ions are linked by inter-molecular N-H⋯O and C-H⋯O hydrogen bonds.

In the title compound, C(15)H(17)NO(3)S, the two aromatic rings make a dihedral angle of 69.42 (9)° with each other and the bridging C-N-S-C torsion angle is 65.76 (16)°. Weak intra-molecular C-H⋯O inter-actions may affect the mol-ecular conformation. Two neighbouring mol-ecules generate a hydrogen-bonded dimer about a center of inversion through a pair of inter-molecular N-H⋯O inter-actions, forming an R(2) (2)(8) ring motif. Furthermore, two inter-molecular C-H⋯π inter-actions contribute to the stability of the crystal packing.

In the title compound, C(7)H(6)ClNO(2), the nitro group is almost coplanar with the aromatic ring [dihedral angle = 2.9 (2)°], but the Cl atom deviates from the ring plane by 1.129 (1) Å. In the crystal, mol-ecules are linked by weak C-H⋯O inter-actions to generate chains.

In the title mol-ecule, C(7)H(6)ClNO(2), the plane of the nitro group and the direction of the chloro-methyl group are twisted away from the benzene ring, forming dihedral angles of 8.2 (3) and 67.55 (12)°, respectively. In the crystal structure, weak inter-molecular C-H⋯O inter-actions link the mol-ecules into corrugated sheets parallel to the bc plane.

The title compound, C(7)H(8)O(4), isolated from Opuntia dillenii Haw (Cacta-ceae), is almost planar [maximum deviation of 0.027 (2) Å] except for the H atoms of the methylene and methyl groups. The crystal packing is stabilized by C-H⋯O and O-H⋯O inter-molecular hydrogen bonds, resulting in the formation of a three-dimensional network.

The mechanism of inhibition of alpha-chymotrypsin by benzoylsalireposide (1), a phenolic glycoside isolated from Symplocos racemosa, was investigated. Lineweaver-Burk and Dixon plots and their secondary replots showed that 1 was a non-competitive inhibitor of this enzyme with the Ki value of 29.60 microM.