51
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Computational simulation, surface characterization, adsorption studies and electrochemical investigation on the interaction of guar gum with mild steel in HCl environment. RESULTS IN CHEMISTRY 2020. [DOI: 10.1016/j.rechem.2020.100054] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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52
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Udofia IA, Ogunbayo TB, Oloba-Whenu OA, Isanbor C, Ramasami P. Investigation of the reactivity indices for the formation of substituted dinitroanilines and correlations to their dockings on α-tubulin of Plasmodium falciparum. J Mol Model 2019; 25:342. [PMID: 31713698 DOI: 10.1007/s00894-019-4169-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 08/15/2019] [Indexed: 11/29/2022]
Abstract
The local and global reactivity descriptors of substituted dinitroaniline analogues were investigated using M06-2X/6-31 + G(d,p) method. It was observed that NH2 (m = 3.53 eV; p = 3.70 eV) substituent conveyed the highest nucleophilic character on the benzene ring system than the other groups under study. For the substrates 4-substituted-1-chloro-2,6-dinitrobenzenes, the condensed to atom electrophilicity ([Formula: see text]) increases in the order COOCH3 > NO2 > F > SO3H > CN > Cl > Br. The para substituted groups with the halogens follow the order of increasing electronegativity, F > Cl > Br. However, the nucleophilicity of the halo substituents of the products increases in the order, F > Br > Cl. Molecular docking simulations using the homology model with the crystallographic structure of zinc-induced bovine tubulin heterodimer (1JFF) as one of the templates reveal that the interactions between the tubulins of Plasmodium falciparum and dinitroaniline analogues are due to H-bonding. In general, the binding interaction is with the following residues: Met137, ARG64, Lys60, Glu183, Val4, His28, Cys171, Tyr224, Asn206, 228, Ile235, and Leu238. The pKas of the residue decrease as the ring activating power of the substituents increases from strongly activating to weakly activating groups. There is no evidence of intra or intermolecular H-bonding between Arg64 and Cys171. Electronegativity (χ) gives a better generic description of the dinitroanilines than any other parameters considered. Short-range hydrophobic interaction contributes to reduced binding affinities of the ligands. Graphical abstractReaction of substituted 2,6-dinitro chlorobenzene with diisopropylamine. Orbital interaction between the substrates and diisopropylamine in the formation of the dinitroanilines.
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Affiliation(s)
| | | | | | | | - Ponnadurai Ramasami
- Computational Chemistry Group, Department of Chemistry, Faculty of Science, University of Mauritius, Réduit, 80837, Mauritius.,Department of Applied Chemistry, University of Johannesburg, PO Box 17011, Doornfontein, Johannesburg, 2028, South Africa
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53
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Synthesis of Pyrazolo-Fused 4-Azafluorenones in an Ionic Liquid. Mechanistic Insights by Joint Studies Using DFT Analysis and Mass Spectrometry. Catalysts 2019. [DOI: 10.3390/catal9100820] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A series of pyrazolo-fused 4-azafluorenones (indeno[1,2-b]pyrazolo[4,3-e]pyridines, IPP) were synthesized via the three-component reaction between arylaldehydes, 3-methyl-1H-pyrazol-5-amine and 1,3-indanedione in an ionic liquid as a catalyst at room temperature. The applied synthetic route has the advantages of easy work-up under mild reaction conditions presenting moderate yields and an environmentally benign procedure. A theoretical study based on conceptual-density functional theory has been done, bond reactivity indices have been calculated and an electrophilic and nucleophilic character of localized orbitals has been determined to analyze the possible electronic mechanisms.
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54
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Sánchez-Márquez J. Correlations between Fukui Indices and Reactivity Descriptors Based on Sanderson’s Principle. J Phys Chem A 2019; 123:8571-8582. [DOI: 10.1021/acs.jpca.9b05571] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jesús Sánchez-Márquez
- Departamento de Química-Física, Facultad de Ciencias, Campus Universitario Río San Pedro, Universidad de Cádiz, 11510 Puerto Real, Cádiz, Spain
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55
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Chen JY, Jiang H, Chen SJ, Cullen C, Ahmed CMS, Lin YH. Characterization of electrophilicity and oxidative potential of atmospheric carbonyls. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2019; 21:856-866. [PMID: 30942229 DOI: 10.1039/c9em00033j] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Carbonyls are reactive and electrophilic compounds found ubiquitously in the atmosphere. The interactions between atmospheric carbonyls and biological nucleophiles (e.g., thiol-containing compounds) have important implications on their toxicity, but the underlying mechanisms have not been fully understood. In this study, we used combined computational and experimental approaches to assess the reactivities of atmospheric carbonyls in respect to their electrophilic properties. Global electrophilicity indexes (ω) were calculated based on density functional theory. The reactivities of carbonyls with thiols were assessed using the dithiothreitol (DTT) assay as a surrogate of biological nucleophilic antioxidants. The computational results indicated that the ω of a given carbonyl compound is largely influenced by its molecular structure and adjacent functional groups. The calculated ω values showed a strong linear correlation with the logarithm of measured carbonyl mass-normalized DTT consumption rates (r2 = 0.8378 and 0.9899 for simple and α,β-unsaturated carbonyls, respectively). The removal of DTT through the nucleophilic addition pathway was confirmed by the detection of carbonyl-DTT adducts using the gas chromatography/electron ionization-mass spectrometry (GC/EI-MS) technique. Our results demonstrated that electrophilicity index can be potentially used as a molecular descriptor to predict toxicity of atmospheric carbonyls towards thiol-containing biomolecules. This work also highlights the significance of carbonyls in interpreting DTT-based aerosol oxidative potential.
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Affiliation(s)
- Jin Y Chen
- Environmental Toxicology Graduate Program, University of California, Riverside, California 92521, USA.
| | - Huanhuan Jiang
- Department of Environmental Sciences, University of California, Riverside, California 92521, USA
| | - Stacy Jy Chen
- Department of Environmental Sciences, University of California, Riverside, California 92521, USA
| | - Cody Cullen
- Department of Chemical Engineering, University of California, Riverside, California 92521, USA
| | - C M Sabbir Ahmed
- Environmental Toxicology Graduate Program, University of California, Riverside, California 92521, USA.
| | - Ying-Hsuan Lin
- Environmental Toxicology Graduate Program, University of California, Riverside, California 92521, USA. and Department of Environmental Sciences, University of California, Riverside, California 92521, USA
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56
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Sánchez-Márquez J. New advances in conceptual-DFT: an alternative way to calculate the Fukui function and dual descriptor. J Mol Model 2019; 25:123. [PMID: 31020412 DOI: 10.1007/s00894-019-4000-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 03/21/2019] [Indexed: 10/26/2022]
Abstract
An alternative way of calculating the Fukui function and the partial derivative of second order of the electronic density with respect to the number of electrons N is presented, the new formulas agree with the usual ones but only in cases without degeneracy. The new operative formulas are more general than the previous ones and are the right ones for those problematic cases where one or both of the frontier molecular orbitals are degenerate. Finally, we present a new way of applying the finite difference approximation that leads to more realistic results than the usual formulas. Graphical abstract A new way of calculating the Fukui function is presented that results in a new operative formula of the function. It has also been obtained the partial derivative of second order of the electronic density with respect to the number of electrons N, and it agree with the usual formula of the dual descriptor function but only in cases without degeneration.
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Affiliation(s)
- Jesús Sánchez-Márquez
- Departamento de Química-Física, Facultad de Ciencias, Campus Universitario Río San Pedro, Universidad de Cádiz, 11510, Puerto Real, Cádiz, Spain.
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57
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Gul M, Eryılmaz S. Synthesis, Antioxidant Activity and Theoretical Investigation of Isoxazolines Derivatives of Monoterpenoids. LETT ORG CHEM 2019. [DOI: 10.2174/1570178616666181226154540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The 3+2 cycloaddition reactions are important to generate five-membered heterocyclic compounds
as well as altering biological activity effects based on structure. In the study, we synthesized
new isoxazoline derivatives of different monoterpenoids and examined the structure analysis using
spectroscopical analysis methods, reveal changes in the theoretical analysis related to the biological activity.
These new compounds exhibit antioxidant activities; DPPH radical scavenging, ferric reducing,
metal chelating activities which are significantly higher than the related commercial monoterpenoids.
Theoretical approaches on the compounds containing isoxazole moiety have been performed by the
DFT/B3LYP/method, 6-31G(d,p) basis set in the ground state. The global and local chemical reactivity
properties of the compounds were investigated by considering the values of electronegativity, global
hardness-softness, electronic chemical potential, electrophilicity index and condensed Fukui functions,
local softness and local electrophilicity index. Furthermore, total energy, FMOs energy values and the
dipole moment (µ), mean polarizability (α), and first order hyperpolarizability (β) values were analysed
at the theoretical level to examine the polarizability characteristics of the compounds. The antioxidant
activity values of the newly synthesized compounds were compared with a finding of the computational
study. The results obtained exhibited good correlation on some parameters.
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Affiliation(s)
- Melek Gul
- Department of Chemistry, Science-Art Faculty, Amasya University, Amasya, Turkey
| | - Serpil Eryılmaz
- Department of Physics, Science-Art Faculty, Amasya University, Amasya, Turkey
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58
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Sulaiman KO, Onawole AT, Faye O, Shuaib DT. Understanding the corrosion inhibition of mild steel by selected green compounds using chemical quantum based assessments and molecular dynamics simulations. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.01.136] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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59
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Wałejko P, Dobrzycki Ł, Ratkiewicz A, Socha P, Witkowski S, Cyrański MK. An X-ray and Natural Bond Orbital (NBO) structural study of α-tocopheryl and 2,2,5,7,8-pentamethylchroman-6-yl succinates. JOURNAL OF SAUDI CHEMICAL SOCIETY 2019. [DOI: 10.1016/j.jscs.2018.08.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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60
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Chauhan DS, Quraishi MA, Sorour AA, Saha SK, Banerjee P. Triazole-modified chitosan: a biomacromolecule as a new environmentally benign corrosion inhibitor for carbon steel in a hydrochloric acid solution. RSC Adv 2019; 9:14990-15003. [PMID: 35516289 PMCID: PMC9064206 DOI: 10.1039/c9ra00986h] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 04/29/2019] [Indexed: 11/21/2022] Open
Abstract
In this work, a new inhibitor, triazole modified chitosan, was synthesized for the first time following chemical modification of chitosan using 4-amino-5-methyl-1,2,4-triazole-3-thiol. The newly synthesized biopolymer (CS–AMT) was characterized using FTIR and NMR, and then it was evaluated as an inhibitor against corrosion of carbon steel in 1 M hydrochloric acid. The corrosion testing and evaluation were performed thoroughly employing the weight loss method, electrochemical measurements and surface analysis. A maximum corrosion inhibition efficiency of >95% was obtained at 200 mg L−1 concentration of inhibitor. The adsorption of inhibitor obeyed the Langmuir isotherm and showed physical and chemical adsorption. The electrochemical study via impedance analysis supported the adsorption of the inhibitor on the surface of carbon steel, and the potentiodynamic polarization indicated a mixed type of inhibitor behavior with cathodic predominance. To get a better insight on the interaction of inhibitor molecules with the metal surface, a detailed theoretical study was performed using DFT calculations, Fukui indices analysis and molecular dynamics (MD) simulation. The DFT study showed a lower energy gap of CS–AMT and the MD simulations showed an increased binding energy of CS–AMT compared to the parent chitosan and triazole moieties thereby supporting the experimental findings. A novel derivative of chitosan is evaluated as an environment-friendly corrosion inhibitor for carbon steel in hydrochloric acid solution.![]()
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Affiliation(s)
- Dheeraj Singh Chauhan
- Center of Research Excellence in Corrosion
- Research Institute
- King Fahd University of Petroleum and Minerals
- Dhahran 31261
- Saudi Arabia
| | - M. A. Quraishi
- Center of Research Excellence in Corrosion
- Research Institute
- King Fahd University of Petroleum and Minerals
- Dhahran 31261
- Saudi Arabia
| | - A. A. Sorour
- Center of Research Excellence in Corrosion
- Research Institute
- King Fahd University of Petroleum and Minerals
- Dhahran 31261
- Saudi Arabia
| | - Sourav Kr. Saha
- Surface Engineering & Tribology Group
- CSIR-Central Mechanical Engineering Research Institute
- Durgapur 713209
- India
| | - Priyabrata Banerjee
- Surface Engineering & Tribology Group
- CSIR-Central Mechanical Engineering Research Institute
- Durgapur 713209
- India
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61
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Tomberg A, Johansson MJ, Norrby PO. A Predictive Tool for Electrophilic Aromatic Substitutions Using Machine Learning. J Org Chem 2018; 84:4695-4703. [PMID: 30336024 DOI: 10.1021/acs.joc.8b02270] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
At the early stages of the drug development process, thousands of compounds are synthesized in order to attain the best possible potency and pharmacokinetic properties. Once successful scaffolds are identified, large libraries of analogues are made, which is a challenging and time-consuming task. Recently, late stage functionalization (LSF) has become increasingly prominent since these reactions selectively functionalize C-H bonds, allowing to quickly produce analogues. Classical electrophilic aromatic halogenations are a powerful type of reaction in the LSF toolkit. However, the introduction of an electrophile in a regioselective manner on a drug-like molecule is a challenging task. Herein we present a machine learning model able to predict the reactive site of an electrophilic aromatic substitution with an accuracy of 93% (internal validation set). The model takes as input a SMILES of a compound and uses six quantum mechanics descriptors to identify its reactive site(s). On an external validation set, 90% of all molecules were correctly predicted.
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62
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Syntheses, density functional and sparkle PM6 semi empirical theoretical studies of O,O′-dialkyl/alkylenedithiophosphate derivatives of tin(IV) phthalocyanine adducts. J Mol Struct 2018. [DOI: 10.1016/j.molstruc.2018.04.039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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63
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Haque J, Srivastava V, Chauhan DS, Lgaz H, Quraishi MA. Microwave-Induced Synthesis of Chitosan Schiff Bases and Their Application as Novel and Green Corrosion Inhibitors: Experimental and Theoretical Approach. ACS OMEGA 2018; 3:5654-5668. [PMID: 31458765 PMCID: PMC6641920 DOI: 10.1021/acsomega.8b00455] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 05/15/2018] [Indexed: 05/22/2023]
Abstract
Environmentally friendly three chitosan Schiff bases (CSBs) were first time synthesized under microwave irradiation by the reaction of chitosan and aldehydes [benzaldehyde (CSB-1), 4-(dimethylamino)benzaldehyde (CSB-2), and 4-hydroxy-3-methoxybenzaldehyde (CSB-3)] and characterized by IR and NMR spectroscopy. The corrosion inhibition performance of the synthesized inhibitors was studied by the electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP). The results show that all the Schiff bases (CSBs) act as effective corrosion inhibitors for mild steel in 1 M HCl solution. Among the synthesized Schiff bases, CSB-3 exhibited the maximum inhibition efficiency of 90.65% at a very low concentration of 50 ppm. The EIS results showed that the CSBs inhibit corrosion by the adsorption mechanism. The PDP results show that all the three Schiff bases are mixed-type inhibitors. The formation of inhibitor films on the mild steel surface was supported by scanning electron microscopy/energy dispersive X-ray analysis and Fourier-transform infrared spectroscopy methods. The adsorption of CSBs on the mild steel surface obeys the Langmuir adsorption isotherm. The theoretical studies via density functional theory and molecular dynamics simulation corroborated the experimental results.
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Affiliation(s)
- Jiyaul Haque
- Department
of Chemistry, Indian Institute of Technology
(Banaras Hindu University), Varanasi 221005, India
| | - Vandana Srivastava
- Department
of Chemistry, Indian Institute of Technology
(Banaras Hindu University), Varanasi 221005, India
| | - Dheeraj S. Chauhan
- Center
of Research Excellence in Corrosion, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Hassane Lgaz
- Department
of Applied Bioscience, College of Life & Environment Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, South Korea
| | - Mumtaz A. Quraishi
- Department
of Chemistry, Indian Institute of Technology
(Banaras Hindu University), Varanasi 221005, India
- Center
of Research Excellence in Corrosion, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
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64
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Sánchez-Márquez J, Zorrilla D, García V, Fernández M. Introducing a new methodology for the calculation of local philicity and multiphilic descriptor: an alternative to the finite difference approximation. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1445875] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Jesús Sánchez-Márquez
- Departamento de Química-Física, Facultad de Ciencias, Universidad de Cádiz, Cádiz, Spain
- IMEYMAT: Institute of Research on Electron Microscopy and Materials of the University of Cádiz, Cádiz, Spain
| | - David Zorrilla
- Departamento de Química-Física, Facultad de Ciencias, Universidad de Cádiz, Cádiz, Spain
- IMEYMAT: Institute of Research on Electron Microscopy and Materials of the University of Cádiz, Cádiz, Spain
| | - Víctor García
- Departamento de Química-Física, Facultad de Ciencias, Universidad de Cádiz, Cádiz, Spain
| | - Manuel Fernández
- Departamento de Química-Física, Facultad de Ciencias, Universidad de Cádiz, Cádiz, Spain
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65
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Effect of electron donating functional groups on corrosion inhibition of mild steel in hydrochloric acid: Experimental and quantum chemical study. J Taiwan Inst Chem Eng 2018. [DOI: 10.1016/j.jtice.2017.09.021] [Citation(s) in RCA: 167] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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66
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Introducing a new bond reactivity index: Philicities for natural bond orbitals. J Mol Model 2017; 24:25. [PMID: 29273935 DOI: 10.1007/s00894-017-3553-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 12/01/2017] [Indexed: 10/18/2022]
Abstract
In the present work, a new methodology defined for obtaining reactivity indices (philicities) is proposed. This is based on reactivity functions such as the Fukui function or the dual descriptor, and makes it possible to project the information from reactivity functions onto molecular orbitals, instead of onto the atoms of the molecule (atomic reactivity indices). The methodology focuses on the molecules' natural bond orbitals (bond reactivity indices) because these orbitals have the advantage of being localized, allowing the reaction site of an electrophile or nucleophile to be determined within a very precise molecular region. This methodology provides a "philicity" index for every NBO, and a representative set of molecules has been used to test the new definition. A new methodology has also been developed to compare the "finite difference" and the "frontier molecular orbital" approximations. To facilitate their use, the proposed methodology as well as the possibility of calculating the new indices have been implemented in a new version of UCA-FUKUI software. In addition, condensation schemes based on atomic populations of the "atoms in molecules" theory, the Hirshfeld population analysis, the approximation of Mulliken (with a minimal basis set) and electrostatic potential-derived charges have also been implemented, including the calculation of "bond reactivity indices" defined in previous studies. Graphical abstract A new methodology defined for obtaining bond reactivity indices (philicities) is proposed and makes it possible to project the information from reactivity functions onto molecular orbitals. The proposed methodology as well as the possibility of calculating the new indices have been implemented in a new version of UCA-FUKUI software. In addition, this version can use new atomic condensation schemes and new "utilities" have also been included in this second version.
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67
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Singh A, Ansari KR, Xu X, Sun Z, Kumar A, Lin Y. An impending inhibitor useful for the oil and gas production industry: Weight loss, electrochemical, surface and quantum chemical calculation. Sci Rep 2017; 7:14904. [PMID: 29097741 PMCID: PMC5668278 DOI: 10.1038/s41598-017-13877-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 10/03/2017] [Indexed: 12/13/2022] Open
Abstract
The influence of a Schiff base namely N,N'-(pyridine-2,6-diyl)bis(1-(4-methoxyphenyl) methanimine) (PM) on the corrosion of J55 and N80 steel in 3.5 wt.% NaCl solution saturated with CO2 was evaluated using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD), contact angle, scanning electron microscopy (SEM), atomic force microscopy (AFM) and scanning electrochemical microscopy (SECM). Potentiodynamic polarization results suggested that the inhibitor acted as a mixed type inhibitor by reducing both anodic and cathodic reactions. The adsorption of PM on the J55 and N80 steel surface obeyed the Langmuir adsorption isotherm. XRD, contact angle, SEM, AFM and SECM studies revealed that the surface of the metal was quite unaffected after the addition of inhibitor. Quantum chemical calculations and molecular dynamic simulation support the experimental results well.
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Affiliation(s)
- Ambrish Singh
- School of Materials Science and Engineering, Southwest Petroleum University, Chengdu, 610500, Sichuan, China.
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan, 610500, China.
| | - K R Ansari
- Department of Chemistry, Indian Institute of Technology, Banaras Hindu University, Varanasi, 221005, U.P., India
| | - Xihua Xu
- School of Materials Science and Engineering, Southwest Petroleum University, Chengdu, 610500, Sichuan, China
| | - Zhipeng Sun
- School of Materials Science and Engineering, Southwest Petroleum University, Chengdu, 610500, Sichuan, China
| | - Ashok Kumar
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona, 85287-1604, United States of America
| | - Yuanhua Lin
- School of Materials Science and Engineering, Southwest Petroleum University, Chengdu, 610500, Sichuan, China.
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan, 610500, China.
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68
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Synthesis and DFT Calculations of Novel Vanillin-Chalcones and Their 3-Aryl-5-(4-(2-(dimethylamino)-ethoxy)-3-methoxyphenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde Derivatives as Antifungal Agents. Molecules 2017; 22:molecules22091476. [PMID: 29240047 PMCID: PMC6151623 DOI: 10.3390/molecules22091476] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 08/31/2017] [Accepted: 08/31/2017] [Indexed: 01/10/2023] Open
Abstract
Novel (E)-1-(aryl)-3-(4-(2-(dimethylamino)ethoxy)-3-methoxyphenyl) prop-2-en-1-ones 4 were synthesized by a Claisen-Schmidt reaction of 4-(2-(dimethylamino)ethoxy)-3-methoxy-benzaldehyde (2) with several acetophenone derivatives 3. Subsequently, cyclocondensation reactions of chalcones 4 with hydrazine hydrate afforded the new racemic 3-aryl-5-(4-(2-(dimethylamino)ethoxy)-3-methoxyphenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehydes 5 when the reaction was carried out in formic acid. The antifungal activity of both series of compounds against eight fungal species was determined. In general, chalcone derivatives 4 showed better activities than pyrazolines 5 against all tested fungi. None of the compounds 4a–g and 5a–g showed activity against the three Aspergillus spp. In contrast, most of the compounds 4 showed moderate to high activities against three dermatophytes (MICs 31.25–62.5 µg/mL), being 4a followed by 4c the most active structures. Interestingly, 4a and 4c possess fungicidal rather than fungistatic activities, with MFC values between 31.25 and 62.5 μg/mL. The comparison of the percentages of inhibition of C. neoformans by the most active compounds 4, allowed us to know the role played by the different substituents of the chalcones’ A-ring. Also the most anti-cryptococcal compounds 4a–c and 4g, were tested in a second panel of five clinical C. neoformans strains in order to have an overview of their inhibition capacity not only of standardized but also of clinical C. neoformans strains. DFT calculations showed that the electrophilicity is the main electronic property to explain the differences in antifungal activities for the synthesized chalcones and pyrazolines compounds. Furthermore, a quantitative reactivity analysis showed that electron-withdrawing substituted chalcones presented the higher electrophilic character and hence, the greater antifungal activities among compounds of series 4.
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69
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Dohare P, Ansari K, Quraishi M, Obot I. Pyranpyrazole derivatives as novel corrosion inhibitors for mild steel useful for industrial pickling process: Experimental and Quantum Chemical study. J IND ENG CHEM 2017. [DOI: 10.1016/j.jiec.2017.03.044] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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70
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Navarro R, Monterde C, Molina S, Pérez-Perrino M, Reviriego F, del Prado A, Gallardo A, Reinecke H. Understanding the regioselectivity of Michael addition reactions to asymmetric divinylic compounds. RSC Adv 2017. [DOI: 10.1039/c7ra11005g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
In the present paper, we describe the synthesis of novel monomers prepared by regioselective Michael addition to asymmetric divinylic compounds.
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Affiliation(s)
| | - Cristina Monterde
- Institute of Organic Chemistry
- Spain
- Institute of Material Science
- Cantoblanco
- Spain
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Sánchez-Márquez J. Introducing new reactivity descriptors: “Bond reactivity indices.” Comparison of the new definitions and atomic reactivity indices. J Chem Phys 2016; 145:194105. [DOI: 10.1063/1.4967293] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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72
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Etemadi Y, Shiri A, Eshghi H, Akbarzadeh M, Saadat K, Mozafari S, Beyzaei H, Moghaddam-Manesh M. Synthesis, Characterisation, and in Vitro Antibacterial Evaluation of a New Class of 2-substituted-4-methyl-7,8-dihydro-5H-pyrimido[4,5-d]thiazolo[3,2-a] Pyrimidines. JOURNAL OF CHEMICAL RESEARCH 2016. [DOI: 10.3184/174751916x14737838285904] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The reaction of 2,4-dichloro-5-(chloromethyl)-6-methylpyrimidine with 4,5-dihydrothiazol-2-amine in chloroform led to the formation of 2-chloro-4-methyl-7,8-dihydro-5H-pyrimido[4,5-d]thiazolo[3,2-a]pyrimidine (3). The true structure of the target compound was confirmed by density functional theory calculations of condensed Fukui indices. The substitution of the 2-Cl function in compound 3 with different secondary amines yielded 2-substituted-4-methyl-7,8-dihydro-5H-pyrimido[4,5-d]thiazolo[3,2-a]pyrimidines in good yields. The assigned products were tested for their potential antibacterial activity and the results indicated that a few derivatives are valuable compounds with great potential to be used as antibacterial agents.
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Affiliation(s)
- Yasaman Etemadi
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Ali Shiri
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Hossein Eshghi
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Marzieh Akbarzadeh
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Kayvan Saadat
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Sarinasadat Mozafari
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Hamid Beyzaei
- Department of Chemistry, Faculty of Science, University of Zabol, Zabol, Iran
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73
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Sulaiman KO, Onawole AT. Quantum chemical evaluation of the corrosion inhibition of novel aromatic hydrazide derivatives on mild steel in hydrochloric acid. COMPUT THEOR CHEM 2016. [DOI: 10.1016/j.comptc.2016.08.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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74
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Akaberi T, Shiri A, Sheikhi-Mohammareh S. Synthesis of New Derivatives of Pyridazino[6,1-c]Pyrimido[5,4-e][1,2,4]Triazine; a Novel Heterocyclic System. JOURNAL OF CHEMICAL RESEARCH 2016. [DOI: 10.3184/174751916x14497690510968] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Several derivatives of the novel pyridazino[6,1-c]pyrimido[5,4-e][1,2,4]triazine ring system have been synthesised through heterocyclisation of 5-bromo-2,4-dichloro-6-methylpyrimidine with 3-chloro-6-hydrazinylpyridazine followed by treatment with secondary amines in boiling ethanol.
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Affiliation(s)
- Toktam Akaberi
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Ali Shiri
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
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Marmitt S, Gonçalves PFB. A DFT study on the insertion of CO2into styrene oxide catalyzed by 1-butyl-3-methyl-Imidazolium bromide ionic liquid. J Comput Chem 2015; 36:1322-33. [DOI: 10.1002/jcc.23930] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/03/2015] [Accepted: 04/04/2015] [Indexed: 01/05/2023]
Affiliation(s)
- Sandro Marmitt
- Theoretical Chemistry Group; Institute of Chemistry; UFRGS, Av. Bento Gonçalves, 9500 Porto Alegre 91501-970 RS Brazil
| | - Paulo F. B. Gonçalves
- Theoretical Chemistry Group; Institute of Chemistry; UFRGS, Av. Bento Gonçalves, 9500 Porto Alegre 91501-970 RS Brazil
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76
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Reactivity indices for natural bond orbitals: a new methodology. J Mol Model 2015; 21:82. [PMID: 25761421 DOI: 10.1007/s00894-015-2610-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 02/08/2015] [Indexed: 12/22/2022]
Abstract
A new reactivity index has been defined; this parameter is focused on a molecule's natural bond orbitals (NBOs) and derives in a natural way from Fukui functions. NBOs have the advantage of being very localized, allowing the reaction site of an electrophile or nucleophile to be determined within a very precise molecular region. Finally, the indices for a representative set of organic molecules were calculated and their usefulness tested on some protonation reactions.
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