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• A novel series of triazole, sulfonamide and sulfonyl urea derivatives of N -acylhomoserine lactones (HSL) have been prepared. • These novel molecules were screened against Chromobacterium violaceum ATCC 12472 for their quorum sensing inhibitory (QSI) activity. • Among them, compounds 6, 7 and 14 showed comparable antibacterial activities with reference to penicillin and streptomycin as 37.5 µg/mL, while compounds 7, 13 and 17 exhibited promising QSI activity. Triazole, sulfonamide and sulfonyl urea derivatives of N -acylhomoserine lactones (AHLs) have been prepared from homoserine lactone hydrobromide which in turn is derived from l -methionine. The molecules were screened against Chromobacterium violaceum ATCC 12472 for their quorum sensing inhibitory (QSI) activity. Among them, compounds 6, 7 and 14 were exhibited comparable antibacterial activities with reference to penicillin and streptomycin as 37.5 µg/mL, while compounds 7, 13 and 17 exhibited promising QSI activity. These compounds represent a synthetically accessible class of AHL analogs could find utility to improve their potency. [Display omitted] [ABSTRACT FROM AUTHOR]

A new sulfonamide-derived prophane sulfonyl hydrazone compounds: 2-hydroxy- acetophenoneprophanesulfonylhydrazone (afpsh) , 5-Cl-2-hydroxyacetophenoneprophane sulfonylhydrazone (5-Clafpsh) , 3,5-di-tert-butyl-2-hydroxybenzaldehydeprophanesulfonyl hydrazone (3,5tbsalpsh) and their Pd(II) complexes were synthesized. The characterization of all compounds was characterized by 1H NMR, 13C NMR, FT-IR, Mass spectral data, elemental analysis and magnetic susceptibility measurements. The crystal structure of afpsh was determined by single crystal X-ray diffraction methods. 1H and 13C shielding tensors of afpsh were calculated with GIAO/DFT/B3LYP/6–311++G(d,p) methods in DMSO. Molecular electrostatic potential surface and frontier orbital analysis were also carried out. HOMO-LUMO energy gap was calculated which allowed the calculation of relative reactivity descriptors like chemical hardness, chemical inertness, chemical potential, nucleophilicity and electrophilicity index of all compounds. It has been observed that the calculated band gaps for Pd (II) complexes are much smaller than ligands. The microbiological effect of ligands and Pd(II) complexes were tested against six human pathogenic bacteria (three Gram-positive and three Gram-negative strains) by using microdilution (as MICs) and disc diffusion (as mm zone) methods. It was found that all compounds, in particular Pd (II) complexes, were more active than sulfonyl hydrazones. Image 1 • Novel Pd(II) complexes with sulfonyl hydrazones were synthesized. • Single crystal X-ray studies revealed the structure of the afpsh. • The minimum inhibitory concentration of the sulfony hdrazone and Pd(II) complexes against bacterial strains was determined. • The Pd(II) compexes of sulfonyl hydrazone emerged as good bacterial inhibitors. • Bioactivity studies show that the Pd(II) complex can interact with in vitro. [ABSTRACT FROM AUTHOR]

Abstract In this paper, p -toluenesulfonamide,N,N′-1,3-propanediylbis ( ptspr ) and [Cu(II) (phenanthroline) 2 ]ptspr compounds has been synthesized for the first time and they characterized by X-ray diffraction, elemental analysis, FT-IR, 1H, 13C, heteronuclear chemical-shift correlation (HETCOR) and correlation spectroscopy (COSY) NMR spectroscopies. The optimized molecular structures of the compounds were also calculated by using the DFT/B3LYP method with 6–311++G (d,p)/LanL2DZ basis sets. The vibrational frequencies, intensities of vibrational bands and, H C nuclear magnetic resonance (NMR) chemical shifts of the molecules were calculated. Additionally, nonlinear optical properties (NLO), fragments contributions in HOMO and LUMO molecular orbitals were investigated with the same level of theory. All of the calculated properties were compared with the experimental values of this study and it is seen that all physical and chemical parameters calculated are very consistent with the experimental results. In addition, the antimicrobial activities of synthesized compounds were studied against some Gram-positive and Gram-negative bacteria by using the microdilution and disk diffusion method. It was determined from the results of this study that the antimicrobial activity screening showed the complex have more activity than ligand against the tested bacteria. Graphical abstract Image Highlights • The novel crystal structure of ptspr was synthesized. • Mid-IR spectrum of the new crystal structure have been recorded. • [Cu(II) (phenanthroline) 2 ]ptspr complex was synthesized and characterized. • The molecular and vibrational properties have computed. • The HOMO-LUMO and NLO properties were investigated. [ABSTRACT FROM AUTHOR]

This context explains the condensation of various arylsulfonohydrazides with two pyrazole aldehydes to get corresponding hydrazones ( 6a-f ). The hydrazones synthesized were confirmed with the help of IR, NMR, Mass and single crystal X-ray diffraction techniques. From the X-ray analysis it was observed that, all the three compounds 6a, 6c and 6f crystallizes in monoclinic crystal system with P 2 1 / c , P 2 1 / n and P 2 1 / n space group respectively. The intermolecular hydrogen bond interactions of the type N H⋯O, C H⋯O, C H….C, O H ⋯O, O H⋯N and C H⋯N plays a significant role in the stability of the molecules. The 3D Hirshfeld analyses and 2D fingerprint plots were helpful in decoding the behavior of the interactions and their quantitative contributions towards the packing structure of the crystals. In addition to this, TGA and DTA curves were helpful in explaining the thermal stability of the compounds. Additionally, the antibacterial effectiveness of the molecules synthesized ( 6a-f ) was analyzed against Gram-negative and Gram-positive strains. Interestingly, the compounds with fluorinated pyrazoles ( 6a and 6c ) emerged as good bacterial inhibitors, having scope to produce potent therapeutics in future. [ABSTRACT FROM AUTHOR]

Conformational composition of the vapor (T = 413(5) K) and the conformer structures of 1,5-naphthalenedisulfonylchloride (1,5-NaphDSC) have been studied by a combined gas-phase electron diffraction and mass spectrometry (GED/MS) method complemented by quantum chemical calculations. According to quantum chemical calculations at DFT/B3LYP/cc-pVTZ and MP2/cc-pVTZ theory levels, the molecule 1,5-NaphDSC possesses four conformers differing mutual orientation of the two SO 2 Cl groups. GED data clearly indicate that only two conformers, whose structures are characterized by deviation of two S Cl bonds from perpendicular position relative to the plane of the naphthalene skeleton (syn-symmetry C 2 and anti-symmetry C i ), are present in vapor at 413 K. The following geometrical parameters of these conformers were obtained from the experiment (Å and degrees; uncertainties are in parentheses): r h1 (C H) = 1.098(9), r h1 (C C) = 1.405(3), r h1 (C S) = 1.781(4), r h1 (S O) = 1.426(3), r h1 (S Cl) = 2.056(4), ∠C C S C = 122.9(1), ∠C S S Cl = 101.8(6); C9 C1 S Cl = 71.2(12), C10 C5 S Cl = 71.2(12)-syn conformer; C9 C1 S Cl = 71.2(12), C10 C5 S Cl = −71.2(12) -anti-conformer. The presence of C 9 H n + ions in the mass spectra of naphthalenesulfonyl chlorides, which are absent in the mass spectrum of naphthalene, may be attributed to the weakening of two C C bonds adjacent to the substituent of the naphthalene skeleton. This reflects in the geometric parameters of 1,5-NaphDSC. The barriers to internal rotation of sulfonyl chloride groups were calculated. It is shown that the low-energy syn- and anti-conformers are structurally rigid, in contrast to high-energy conformers with one or two S Cl bonds, lying in the plane of the naphthalene skeleton. The dependence of C1 C2, C S, S Cl bond lengths from SO 2 Cl groups orientation relative to naphthalene skeleton is discussed in terms of NBO-analysis of electron density distribution. The relationship between conformational properties of molecule and some physicochemical characteristics of the 1,5-NaphDSC compound is discussed. [ABSTRACT FROM AUTHOR]

• Concise, high-yield method for the synthesis of nine-membered sulfonyl benzocyclononadienols. • Allylmagnesium bromide exhibits good Grignard 1,2-allylation. • Grubbs second-generation catalyst performs excellent ring-closing metathesis. • Carbon-carbon single bond (C-C) and carbon-carbon double bond (C=C) formations. We describe a concise, high-yield method for the synthesis of sulfonyl benzocyclononadienols by a two-step synthetic route, including (i) Grignard 1,2-allylation of sulfonyl chalcones, and (ii) sequential ring-closing metathesis of the resulting dienyl tertiary alcohols with Grubbs second-generation catalyst. This protocol provides a highly effective annulation via one carbon-carbon single bond (C-C) and one carbon-carbon double bond (C=C) formations. Table of contents entry: We describe the synthesis of sulfonyl benzocyclononadienols by Grignard 1,2-allylation of sulfonyl chalcones, and sequential ring-closing metathesis of the resulting dienyl tertiary alcohols with Grubbs second-generation catalyst. [Display omitted] [ABSTRACT FROM AUTHOR]

The present study describes the syntheses and biological investigations of sulfonyl hydrazides and their novel derivatives. The detailed investigations involved the characterization of the newly synthesized compounds using FTIR, NMR, mass spectrometry and by single crystal X-Ray diffraction (XRD) analysis techniques. The binding tendencies of these compounds with CT-DNA (calf thymus DNA) have been explored by electronic absorption (UV) spectroscopy and viscosity measurement. The binding constant (K) and Gibb's free energy (ΔG) values were also calculated accordingly. In addition, we also investigated the biological activities such as antioxidant, antibacterial, enzyme inhibition and DNA interactions. The antioxidant activity was assayed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, while antibacterial activity was investigated against four bacterial strains ( viz. Escherichia coli , Crynibacteria bovius , Staphylococcus auras and Bacillus antherasis ) by employing the common disc diffusion method. Enzyme inhibition activity of the synthesized compounds was examined against butyrylcholinestrase. The results of enzyme inhibition activity and the DNA binding interaction studies were also collected through molecular docking program using computational analysis. Our study reveals that the newly synthesized compounds possess moderate to good biological activities. [ABSTRACT FROM AUTHOR]

Bis-camphorsulfonyl urea, a newly developed hydrogen bonding catalyst, was evaluated in an enantioselective Friedel–Crafts reaction. We observed that complexation of the sulfonyl urea with a sodium cation enhanced the selectivity of reactions in comparison to reactions performed with urea alone. To understand the role of sodium cation, we performed Infrared and Raman spectroscopic studies. The detailed band assignment of the molecule was made by calculating spectra using Density Functional theory. Our studies suggest that the binding of the cation takes place through the oxygen atoms of carbonyl and sulfonyl groups. Natural Bond Orbital (NBO) analysis shows the expected charge distribution after sodium binding. The changes in the geometrical parameter and charge distribution are in line with the experimentally observed spectral changes. Based on these studies, we conclude that binding of the sodium cation changes the conformation of the sulfonyl urea to bring the chiral camphor groups closer to the incipient chiral center. [ABSTRACT FROM AUTHOR]

The analysis of infrared (IR) carbonyl bands of some 4′-substituted 2-(phenylselanyl)-2-(ethylsulfonyl)-acetophenones 1 – 5 bearing substituents NO 2 1 , Br 2 , H 3 , Me 4 and OMe 5 , supported by B3LYP/6–31 + G(d,p) and single point polarizable continuum model calculations, along with natural bond orbital (NBO) analysis (for 1 , 3 , 5 ) and X-ray diffraction (for 4 ) was performed. Theoretical data indicated the existence of two stable conformations: c 1 and c 2 . The former exhibits the highest ν CO frequency and corresponds to the most stable (for 1 – 5 ) and to the most polar one (for 2 – 4 ). The sum of the energy contributions of selected orbital interactions (NBO analysis) of 1 , 3 and 5 is quite similar for both conformers. Nevertheless, adding the LP O(CO) → σ ∗ C H[CH2(Et)] and LP O(SO2) → σ ∗ C H( o SePh) orbital interaction energies, the c 1 conformer becomes significantly more stable than the c 2 one. The occurrence of these hydrogen bonds plays an important role in determining the geometry of the c 1 conformer. This geometry allows the oppositely charged O δ− (CO) ⋯S δ+ (SO2) and O δ− (SO2) ⋯C δ+ (CO) atoms of the carbonyl and sulfonyl groups to assume interatomic distances shorter than the sum of the van der Waals radii that stabilize the referred conformer. Likewise, this geometry favours the O δ− (CO) ⋯O δ− (SO2) short contact and the consequent repulsive field effect that increases the ν CO frequency of the c 1 conformer to a greater extent with respect to that of the c 2 one. Therefore, the more intense higher frequency carbonyl doublet component in the IR spectrum in solution can be ascribed to the c 1 conformer and the less intense component at lower frequency to the c 2 one. X-ray single crystal analysis of 4 indicates that this compound adopts the c 1 geometry. The molecules in the solid are linked in centrosymmetrical pairs through C9 H10⋯O36 hydrogen bond interaction along with the LP Se ⋯π Ph interaction. [ABSTRACT FROM AUTHOR]

Highlights: [•] Three ferrocene-based sulfonyl-substituted dihydropyrazoles 3a–c are synthesized in moderate yields. [•] Molecular structure of 3a has been characterized by single-crystal X-ray diffraction analysis for a first time. [•] The electrochemical behaviors of 3a–c are discussed; the electrochemical inequivalence of 3a was confirmed by DFT. [•] Dinuclear ferrocenyl pyrazole 3a shows a greater catalytic effect on the decomposition temperature of AP than 3b–c. [Copyright &y& Elsevier]

• The sulfonamide bearing thiadiazole derivatives were synthesized as enzyme inhibitors. • Target compounds bind strongly with the target enzyme (PDBID 1V9E). • The compounds show anticancer activity through carbonic anhydrase inhibition rather than by DNA binding. A series of sulfonamide derivatives bearing 2,5-disubstituted-1,3,4-thiadiazole (5a–j) have been synthesized. Thiosemicarbazide was reacted with CS 2 to get 2-amino-5-mercapto-1,3,4-thiadiazole 1. The intermediate thiadiazole (1) was alkylated by reacting with different halides (2a–c) to afford the alkylated thiadiazoles (3a–c). The title sulfonamide bearing derivatives (5a–j) have been prepared by condensation of sulfonyl chlorides (4a–d) with thiadiazole derivatives (3a–c). The molecular docking studies of target molecules showed strong binding of compounds (5a–j) with target enzyme (PDBID 1V9E) particularly for compound 5f containing fluoro and methoxy groups. The carbonic anhydrase (CA) inhibitory activity showed derivative 5h to be the most potent (IC 50 0.60 ± 0.02 µM) as compared to acetazolamide (IC 50 0.984 ± 0.12 µM) used as standard. Free radical scavenging activity was measured using ascorbic acid as a reference. It was observed that just like CA inhibition the compound 5h showed greater free radical scavenging activity than all other target molecules. Enzyme inhibition kinetics (Lineweaver-Burk plots) showed a compound (5h) to inhibit the enzyme by mixed type of inhibition (Ki and Kiʹ values 2.91 µM and 3.88 µM, respectively). Compound 5h was further investigated that a smaller value of Ki than Ki ′ showed preferred competitive binding over non-competitive manners. The anticancer activity performed against the MCF-7 cell line showed that the compound 5h inhibits 40% cell growth at 125 µM concentration. The mechanism of anticancer potential was further investigated by DNA binding studies through electrochemical methods. The UV-Vis spectroscopy and Cyclic voltammetry results suggested that 5h was weakly bound to DNA (binding constant 30–32 M−1). It is thus proposed that anticancer activity of 5h may be through carbonic anhydrase inhibition rather than by DNA binding. Our investigations suggested the derivative 5h to serve as a lead structure in designing potentially more active carbonic anhydrase inhibitors. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The analysis of the infrared (IR) carbonyl band of some 3-(4′-substituted phenylsulfonyl)-1-methyl-2-piperidones 1–5 bearing as substituents: OMe 1, Me 2, H 3, Cl 4 and NO2 5, supported by B3LYP/6-31G(d,p) calculations along with NBO analysis (for 1, 3 and 5) and X-ray diffraction (for 5), indicated the existence of three stable conformations i.e. quasi-axial (q-ax), syn-clinal (s-cl) and quasi-equatorial (q-eq). In the gas phase, the q-ax conformer is calculated as the most stable (ca. 88%) and the least polar, the s-cl conformer is less stable (ca. 12%) but more polar, and the q-eq conformer is the least stable (ca. 1%) and the most polar of the three conformers evaluated. The sum of the most important orbital interactions from NBO analysis and the trend of the electrostatic interactions accounts for the relative populations as well as for the ν CO frequencies of the q-ax, s-cl and q-eq conformers calculated in the gas phase. The unique IR ν CO band in CCl4 may be ascribed to the most stable q-ax conformer. The more intense (60%) high frequency doublet component in CHCl3 may be assigned to the summing up of the least stable q-eq and the less stable s-cl conformers, as their frequencies are almost coincident. The occurrence of only a single ν CO band in both CH2Cl2 and CH3CN supports the fact that the ν CO band of the two more polar conformers appear as a single band. Additional support to this rationalization is given by the single point PCM method, which showed a progressive increase of the q-eq + s-cl/q-ax population ratio going from the gas phase to CCl4, to CHCl3, to CH2Cl2 and to CH3CN. X-ray single crystal analysis of 5 indicates that this compound displays a quasi-axial geometry with respect to the [Oh name="sbnd" />CH, and that the 2-piperidone ring assumes a slightly distorted half-chair conformation. In the crystal packing, molecules of 5 are arranged into supramolecular layers linked through CO interactions along with π⋯π interactions between adjacent benzene rings. [Copyright &y& Elsevier]

• The structure of compound 1 was determined through single crystal X-Ray diffraction. • In-Vitro enzyme inhibition potential were checked in order to explore their biological importance. • DFT and Docking studies were used to compare experimental and theoretical parameters. This study describes the synthesis of four (1-4) new phenylalanine based sulfonamides from benzene sulfonyl chlorides. The progress of the reaction was monitored on TLC and after completion; the products were subjected to various analyses that indicated the synthesis of the targeted molecules. The structure of sulfonamide 1 was elucidated on the basis of Single Crystal X-Ray Diffraction technique. While other sulfonamides were characterized with FTIR spectroscopy. The sulfonamide (1-4) were subjected to Density Functional Theory for optimization of the structures and to calculate the bond angle and bond length of the crystalline molecule (1). The DFT and SCXRD results are in close agreement with each other. All compounds were subjected to radical scavenging and enzyme inhibition studies. The compound 1 exhibited moderate antioxidant activity (38.04 %). Enzyme inhibition potential was checked against three enzymes; trypsin, acetylcholine esterase and butyrylcholine esterase using in-vitro models. This study indicated that 2-(4-acetamidophenylsulfonamido)-3-phenylpropanoic acid (1) was found most active among all the synthetic molecules. It exhibited inhibition of 54.07%, 72.42and 57.18 % against AChE, BChE and trypsin respectively. Docking studies of the four sulfonamides were also done with Molecular Operating Environment, which depicted good docking scores. In-silico studies also suggested good enzyme inhibition potential of these understudied molecules. [Display omitted] [ABSTRACT FROM AUTHOR]

• Simplified theoretical strategy for prediction of the most possible target ionic liquid. • Highly symmetric crystal structure. • Surprising solubility of ionic liquids containing the hydrophobic anion in water. • The facile distinguishing method. Based on structure –property relationship and the theoretical prediction obtained by DFT calculation, one highly water-soluble and symmetric ionic liquid 1,3-bis(carboxymethyl)imidazolium bis(trifluoromethyl)sulfonyl)amide was designed, successfully synthesized and structurally determined for the first time. The further investigations confirmed that it has surprisingly high solubility in water above room temperature, different to the common ionic liquids containing bis(trifluoromethyl)sulfonyl)amide anion with high hydrophobicity. Additionally, the structural transformation and distinguishment between 1,3-bis(carboxymethyl)imidazolium bis(trifluoromethyl)sulfonyl)amide and its zwitterion were given. Our results reveal that theoretical calculations can compensate some shortcomings of the experiments, and provide valuable information to discover novel ionic liquids. Image, graphical abstract [ABSTRACT FROM AUTHOR]

In the present study, four regio-isomeric isoxazole derivatives (5–8) were synthesized. The structures elucidation was performed using FTIR, NMR, and single crystal X-ray diffraction methods. Electrochemical response of compounds was recorded by cyclic voltammetry (CV). CV results indicated that all the compounds undergo reduction process involving one electron. Compound-DNA interactions were studied using CV titrations and it was observed that all the compounds exhibited interaction with DNA. Compound 8 exhibited strongest interaction with a binding constant (K) value of 5.09 × 104 M−1. Image 1 • Novel regio-isomeric sulfonyl esters of substituted isoxazoles have been synthesized successfully. • Single crystal X-ray crystallographic studies revealed that all the compounds crystallize in monoclinic space groups. • Electrochemical studies revealed that all the compounds undergo one electron reduction process. • DNA interaction studies showed that all the compounds interacted with DNA through intercalation mode of interaction. [ABSTRACT FROM AUTHOR]

Charge transfer complex (CTC) formed between (S, S)-bis-N, N-sulfonyl bis- l -phenylalanine dimethylester as donor and 2,3-dichloro-5,6-dicyano- p -benzoquinone (DDQ) as acceptor, has been studied spectrophotometrically. Benesi-Hildebrand and molar ratio methods were applied in order to determine association constant (K CT), molar extinction coefficient (ε CT) and stoichiometric ratio, respectively. The solid CT complex has been synthesized and its structure was characterized via spectroscopic techniques (UV–vis and FT-IR). In order to determine the equilibrium geometries, DFT/CAM-B3LYP has been employed. Moreover, TD-DFT method was used to investigate the electronic structures of donor, acceptor and their complex. Natural bond orbital (NBO) analysis has been used to study the atomic charges and molecular bonding interactions of the interesting complex. These studies show that non-bonding interactions are important in charge transfer complex. • The new CTC complex formed between (S, S)-bis-N, N-sulfonyl bis-L-phenylalanine dimethylester and DDQ was synthesized. • The Benesi-Hildebrand equation was used to calculate the association constant (K). • The CTC was theoretically investigated using DFT: CAM/B3LYP and TD-DFT methods. • The NBO analysis provides a qualitative picture of the Charge-Transfer process. [ABSTRACT FROM AUTHOR]