Multicomponent Synthesis of 2, 4, 6-Triarylpyridine Analogues As Antibacterial And Antiurease Agents

Abstract Five new 2,4,6-triarylpyridine analogues with potential biological importance have been synthesized using the multicomponent reaction (MCR) solid support catalyst synthetic approach. This green synthesis furnished method simplicity, reduce reaction time, and excellent yield, along with an additional feature of catalyst reusability. A number of spectroscopic techniques such as 1H-NMR, IR, and mass spectrometry, confirmed structures of the newly synthesized compounds. Antibacterial and anti-urease activities of these compounds were evaluated. Results revealed that compounds 4a, 4c, 4d, and 4e exhibit significant inhibition against gram-positive bacterial pathogens. Furthermore, all synthesized compounds showed potent urease inhibitory activity with IC50 values ranging from 12.8 ± 1.04 to 23.7 ± 0.23 µM when compared with the standard inhibitor thiourea (IC50 21.0 ± 0.23 µM).In addition, the synthesized derivatives were subjected to density functional theory (DFT) calculations (DFT) to determine the energy of the molecules having biological potential.

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New Pair of 2-Amino-naphthoxazoles Derived from β-Lapachone: Synthesis, Spectral Evaluation and Crystal Structure

Journal of the Brazilian Chemical Society ◽

10.21577/0103-5053.20210003 ◽

2021 ◽

Author(s):

Leonardo Silva ◽

Emanoel Hottes ◽

Ari da Silva ◽

Luan Freire ◽

Guilherme Guedes ◽

...

Keyword(s):

Crystal Structure ◽

Density Functional ◽

Condensation Reaction ◽

Correlation Coefficients ◽

Basic Medium ◽

Synthetic Approach ◽

Spectroscopic Techniques ◽

X Ray Diffraction ◽

Functional Theory ◽

Spectral Evaluation

This work describes a novel synthetic route for obtaining 2-amino-naphthoxazoles derived from β-lapachone, which consists of a condensation reaction between β-lapachone and thiourea in a basic medium. This synthetic approach can be seen as a potential route for obtaining 2-amino-oxazoles from quinones. The obtained amino-naphthoxazoles were characterized by spectroscopic techniques and the crystal structure of one of them was resolved by X-ray diffraction. The experimental results were compared to that obtained through density functional theory (DFT) calculations, revealing high correlation coefficients.

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Nontemplate synthesis, characterization and theoretical study of tetraazamacrocycles

Analele Universitatii Ovidius Constanta - Seria Chimie ◽

10.2478/v10310-012-0020-7 ◽

2012 ◽

Vol 23 (1) ◽

pp. 121-127

Author(s):

İbrahim Șen ◽

Cem Burak Yildiz ◽

Akın Azizoğlu

Keyword(s):

Density Functional ◽

Basis Sets ◽

Frontier Molecular Orbital ◽

Spectroscopic Techniques ◽

Functional Theory ◽

Hartree Fock ◽

H Nmr ◽

Ft Ir ◽

Molecular Electrostatic Potential Maps ◽

C Nmr

Abstract The syntheses of new tetraaza macrocyclic compounds of variable ring sizes by non-template methods and their characterization with the help of elemental analysis and spectroscopic techniques (FT-IR, 1H-NMR, and 13C-NMR) have been reported in detail. The vibrational frequencies determined experimentally are compared with those obtained theoretically from density functional theory (DFT) and Hartree-Fock (HF) calculations. The comparisons between the experimental and theoretical results indicate that B3LYP level with both the 3-21G(d) and 6-31G+(d,p) basis sets is able to provide satisfactory results for predicting IR properties. The frontier molecular orbital diagrams and molecular electrostatic potential maps of title compounds have been also calculated and visualized at the B3LYP/6-31G+(d,p) level of theory.

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Synthesis of urease inhibitory 2, 4-bis (4-cyanobenzyl)glycoluril using sandmeyer reaction and density functional theory investigation

Current Organic Synthesis ◽

10.2174/1570179418666210113162909 ◽

2021 ◽

Vol 18 ◽

Author(s):

Mirza Arfan Yawer ◽

Shehar Bano ◽

Muhammad Saleem ◽

Affiefa Yawer ◽

Riaz Hussain ◽

...

Keyword(s):

Mass Spectrometry ◽

Density Functional Theory ◽

1H Nmr ◽

13C Nmr ◽

Density Functional ◽

Spectroscopic Techniques ◽

Pure Compound ◽

Functional Theory ◽

Sandmeyer Reaction ◽

Urease Enzyme

Aims: The aim of present research was to synthesize glycoluril derivative 2,4-Bis(4-cyanobenzyl)glycoluril through convergent scheme. Background: For this purpose Sandmeyer reaction procedure was employed for the synthesis of said compound. The structure of the pure compound was confirmed by using different spectroscopic techniques such as 1H-NMR, 13C-NMR and (HR-MS) Mass spectrometry. Objective: Convergent synthesis of 2,4-BIS (4-CYANOBENZYL)GLYCOLURIL USING SANDMEYER REACTION and urease inhibition study. Methods: The structure of the pure compound was confirmed by using different spectroscopic techniques such as 1H-NMR, 13C-NMR and (HR-MS) Mass spectrometry. The electronic properties of newly synthesized compound and thiourea were determined by using density functional theory. Results: Furthermore compound was evaluated against urease enzyme and was found to be potent inhibitors with IC50 value of 11.5 ± 1.50 µM when compared with standard inhibitor thiourea (IC50 = 21.0 ± 1.90 µM). Compound may serve as lead compound for the synthesis of new cyano based bambusuril in future with enhanced biological properties. Conclusion: We have synthesized a new glycoluril derivative 2,4-Bis(4-cyanobenzyl)glycoluril by the sandmeyer reaction. It has obtained in the form of light yellowish powder in good yield (96%). Glycoluril based macrocycles have been used in various fields. Starting from the 2,4-Bis(4-nitrobenzyl)glycoluril (already reported compound) which has undergone reduction (CH3OH,Pt/C) , diazotization (NaNO2/HCl), cyanation (CuCl/KCN) respectively in order to synthesize the desired new glycoluril derivative. The obtained product will be used as a building block for the synthesis of the cyano based bambusuril marcocycle in future. The yield of the obtained product has been monitored by using different amount of cyanating reagent but the best results shown by the use of 4 mmol of CuCl/KCN. KCN with CuCl assisted the conversion of diazo group into cyano group with enhanced yield when used in excess amount. It act as a catalyst. Solubility characteristic of 2,4-Bis(4-cyanobenzyl)glycoluril has determined also in different organic solvents. 1H NMR technique proved to be very helpful for the structure determination of our desired product. Benzylic protons give signals at 7.5 ppm and 7.8 ppm respectively. The downfield peaks confirm about the presence of CN group near the benzylic protons. Methine protons show signal at 5.2 ppm which ensures about the basic skeleton of glycoluril. Ureidyl protons also confirm the synthesis of the heterocyclic 2,4-Bis(4-cyanobenzyl)glycoluril compound. The negative and positive electrostatic potential sites, molecular descriptors, and charge density distribution of frontier molecular orbitals are revealing that 4a with promising sites for electrophilic and nucleophilic attacks would result to enhance the urease inhbition which is in good agreement with the experimental data.

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Novel acridine-based thiosemicarbazones as ‘turn-on' chemosensors for selective recognition of fluoride anion: a spectroscopic and theoretical study

Royal Society Open Science ◽

10.1098/rsos.180646 ◽

2018 ◽

Vol 5 (7) ◽

pp. 180646 ◽

Cited By ~ 10

Author(s):

Ibanga Okon Isaac ◽

Iqra Munir ◽

Mariya al-Rashida ◽

Syed Abid Ali ◽

Zahid Shafiq ◽

...

Keyword(s):

Density Functional ◽

Theoretical Study ◽

Fluoride Anion ◽

Metal Fluoride ◽

Visible Absorption ◽

Functional Theory ◽

H Nmr ◽

Tetrabutylammonium Fluoride ◽

Uv Visible ◽

Nickel Fluoride

New thiosemicarbazide-linked acridines 3a–c were prepared and investigated as chemosensors for the detection of biologically and environmentally important anions. The compounds 3a–c were found selective for fluoride (F − ) with no affinity for other anions, i.e. − OAc, Br − , I − , HSO 4 − , SO 4 2− , PO 4 3− , ClO 3 − , ClO 4 − , CN − and SCN − . Further, upon the gradual addition of a fluoride anion (F − ) source (tetrabutylammonium fluoride), a well-defined change in colour of the solution of probes 3a–c was observed. The anion-sensing process was studied in detail via UV–visible absorption, fluorescence and 1 H-NMR experiments. Moreover, during the synthesis of acridine probes 3a–c nickel fluoride (NiF 2 ), a rarely explored transition metal fluoride salt, was used as the catalyst. Theoretical studies via density functional theory were also carried out to further investigate the sensing and anion (F − ) selectivity pattern of these probes.

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Computational characterization of organometallic ligands coordinating metal: Case of azopyridine ligands

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633615500066 ◽

2015 ◽

Vol 14 (01) ◽

pp. 1550006 ◽

Cited By ~ 3

Author(s):

Sopi Thomas Affi ◽

Kafoumba Bamba ◽

Nahossé Ziao

Keyword(s):

Density Functional ◽

Membered Ring ◽

Condensed Phases ◽

Functional Theory ◽

H Nmr ◽

Metal Case ◽

Azo Group ◽

Hydrogen Bond Basicity ◽

Pyridinic Nitrogen

Azpy (2-phenylazopyridine), Nazpy (2-pyridylazonaphtol), Mazpy (2,6-diméthyl-2-phenylazopyridine) and Dazpy (2-phenylazo-4,6-dimethylpyridine) are four pyridylazo ligands that are characterized by density functional theory (DFT) theoretical investigation either in gas or in condensed phases. As they display at least three heteroatoms donors of electrons, hydrogen bond basicity has been experimented via energy and geometrical descriptors to determine which of the donors will link to metal so as to form metallic complexes. The pyridinic Nitrogen ( N py ) and that close to the substituent linked to azo group ( N 2) are the most available with almost the same energy to authorize coordination with metal. Before, prediction of Azpy synthesis was undertaken. 1H NMR was also performed. They showed that the conformational trans or E2-azpy was the most stable existing ligand. Nonetheless, this structure undergoes a modification on behalf of the conformational cis or E1-azpy that is the suitable ligand to provide with two nitrogen atoms with the same energy. Regarding this observation, all calculations were undertaken on the conformational E1 of each pyridylazo ligand. Therefore, the results obtained were consistent with the experimental analysis confirming that all of the four ligands are bidentates. In consequence, all the pyridylazo ligands can be assumed to connect to the metal by two nitrogen atoms forming five membered ring regardless the azo group's substituent nature.

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Synthesis, antioxidant activity, and density functional theory study of catechin derivatives

RSC Advances ◽

10.1039/c7ra11496f ◽

2017 ◽

Vol 7 (85) ◽

pp. 54136-54141 ◽

Cited By ~ 11

Author(s):

Jing Wang ◽

Han Tang ◽

Bo Hou ◽

Pan Zhang ◽

Qi Wang ◽

...

Keyword(s):

Mass Spectrometry ◽

Density Functional Theory ◽

Antioxidant Activity ◽

Density Functional ◽

Density Functional Theory Study ◽

Functional Theory ◽

H Nmr ◽

C Nmr

Catechin derivatives were synthesized, and their structures were characterized by 1H-NMR, 13C-NMR, and mass spectrometry.

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Pt(II) Complexes with Linear Diamines—Part I: Vibrational Study of Pt-Diaminopropane

Spectroscopy An International Journal ◽

10.1155/2012/206297 ◽

2012 ◽

Vol 27 ◽

pp. 403-413 ◽

Cited By ~ 6

Author(s):

Ana L. M. Batista de Carvalho ◽

Sónia M. Fiuza ◽

John Tomkinson ◽

Luís A. E. Batista de Carvalho ◽

M. Paula M. Marques

Keyword(s):

Density Functional ◽

Spectroscopic Techniques ◽

Functional Theory ◽

Vibrational Study ◽

Combined Use ◽

The Density Functional Theory ◽

Mechanical Methods ◽

Reported Data ◽

Theoretical Results ◽

Good Agreement

A conformational analysis of the Pt(dap)Cl2complex (-diaminopropane) was performed by vibrational spectroscopy (FTIR, Raman, and INS), coupled to quantum mechanical methods within the density functional theory (DFT) and effective core potential (ECP) approaches. A complete spectral assignment of the system was achieved, due to the combined use of all available vibrational spectroscopic techniques. A good agreement was found between experimental and theoretical results, as well as with reported data for analogous complexes (e.g., cisplatin).

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NMR and Theoretical Studies on the Conformational Preferences of Some Non-metal Coordinated N-Enoyl Systems Attached to Common Chiral Auxilaries

Journal of the Mexican Chemical Society ◽

10.29356/jmcs.v58i2.162 ◽

2017 ◽

Vol 58 (2) ◽

Author(s):

Rosmarbel Morales-Nava ◽

Alejandro Ramírez-Solís ◽

Mario Fernández-Zertuche

Keyword(s):

Density Functional ◽

Vibrational Analysis ◽

Basis Sets ◽

Chiral Auxiliaries ◽

Nmr Studies ◽

Stable Conformation ◽

Functional Theory ◽

Exchange Correlation ◽

H Nmr ◽

Conformational Preferences

We report a systematic study of a series of N-enoyl systems attached to common oxazolidin-2-ones, oxazolidine-2-thiones and thiazolidine-2-thiones chiral auxiliaries in order to determine the most stable conformation of these compounds. 1H NMR studies show an anti-s-cis structure as the most stable conformation for these series of compounds. Density Functional Theory geometry optimizations and vibrational analysis using the b3lyp exchange-correlation functional with the standard 6-31g** basis sets were done, including solvent effects (chloroform and toluene). Gibbs free energy differences show that the anti-s-cis structures are the most stable conformers lying, on average, ca. 6 kcal/mol lower in energy than the syn-s-cis conformers, widely used to explain the structure and reactivity of N-enoyl systems.

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Synthesis, Characterization and DFT Study of 4,4′-Oxydianiline Imines as Precursors of Tetrahalo-1,3-oxazepine-1,5-dione

Indonesian Journal of Chemistry ◽

10.22146/ijc.22437 ◽

2017 ◽

Vol 17 (2) ◽

pp. 330

Author(s):

Abdullah Hussein Kshash ◽

Mohammed Ghannam Mokhlef

Keyword(s):

Schiff Bases ◽

Phthalic Anhydride ◽

Density Functional ◽

Spectroscopic Techniques ◽

Functional Theory ◽

Homo And Lumo ◽

Ft Ir ◽

Gaussian Program ◽

Theoretical Results ◽

Direct Condensation

This work presents four Schiff bases derived from 4,4′-Oxydianiline, distinguished by the para substituted halogen of benzaldehyde. These bases were used to synthesize eight compounds of di-1,3-oxazepine by direct condensation with tetrachloro phthalic anhydride and tetrabromo phthalic anhydride. The reactions were monitored with TLC and all structures were characterized using spectroscopic techniques such as FT-IR, 1H-NMR, 13C-NMR and C, H, N techniques. On the other hand, a theoretical study by Density Functional Theory (DFT) for the electronic structures was intended to study the effects of para-substituted halogen of benzaldehyde on the electronic structure of synthesized Schiff bases by using the Gaussian program. Theoretical results indicate that there is no effect of halogen atoms except for bromine on HOMO and LUMO energies of the synthesized compounds.

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BIS(BIPYRIDYL)-RU(II)-1-BENZOYL-3-(PYRIDINE-2-YL)-1H-PYRAZOLE AS POTENTIAL PHOTOSENSITISER: EXPERIMENTAL AND DENSITY FUNCTIONAL THEORY STUDY

Jurnal Teknologi ◽

10.11113/jt.v79.11335 ◽

2017 ◽

Vol 79 (5-3) ◽

Author(s):

Wun-Fui Mark-Lee ◽

Febdian Rusydi ◽

Lorna Jeffery Minggu ◽

Takashi Kubo ◽

Mohammad Kassim

Keyword(s):

Density Functional Theory ◽

Electronic Properties ◽

Density Functional ◽

Energy Levels ◽

Spectroscopic Techniques ◽

Functional Theory ◽

Injection Process ◽

Highest Occupied Molecular Orbital ◽

Ligand Charge Transfer ◽

Td Dft

Ru(II) complexes, [Ru(bpy)2(m-R-L)](PF6)2 where bpy = 2,2’-bipyridyl and m-R-L= 1-(meta-R)-benzoyl-3-(pyridine-2-yl)-1H-pyrazole derivatives (R = H, CH3 and Cl) abbreviated as RuL, Ru(m-CH3-L) and Ru(m-Cl-L) complexes, respectively, were synthesized and characterized with spectroscopic techniques namely, infrared, UV-Vis and nuclear magnetic resonance (NMR), photoluminescence and mass spectroscopy. Density functional theory (DFT) and time-dependent (TD) DFT calculations were carried out to study the structural and electronic features of the molecules. These Ru(II) complexes exhibit photo-electronic properties required for a photosensitiser in a TiO2-catalysed photoelectrochemical (PEC) cell. In-depth understanding of the R-L fragment functionality is important to tune the photo-electronic properties of the Ru(II) complex. The highest-occupied molecular orbital (HOMO) is mainly localized at the Ru(II) centre, while the LUMO is dominantly spread across the R-L ligand. The Ru(II) complexes showed favourable metal-to-ligand charge transfer (MLCT) energy levels, which are comparably higher than the conduction band of TiO2 to facilitate electron injection process. Among the Ru(II) complexes, Ru(m-Cl-L) comparatively possesses the highest photoluminescence quantum yield and has the potential to be applied as photosensitiser in PEC systems.

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