DFT Investigations(Geometry Optimization, UV/Vis, FT-IR, NMR, HOMO-LUMO, FMO, MEP, NBO, Excited States) and the Syntheses of New Pyrimidine Dyes

In the present work, the molecular structures of two new synthesized dyes：（4,6-dimethylpyrimidin-2-ylamino）（5-p-tolylisoxazol-3-yl）methanol（PS-1） and N-（4,6-dimethylpyrimidin-2-yl）-5-phenylisoxazole-3-carboxamide（PS-2）, have been investigated using density functional theory（DFT） in dimethylformamide（DMF） for the first time. The electronic spectra of new dyes in a DMF solvent were carried out by time dependent density functional theory（TD-DFT） method. After quantum-chemical calculations two new dyes for the optoelectronic applications were synthesized. FT-IR spectra of the title compounds are recorded and discussed. NucleusIndependent Chemical Shifts（NICS） calculations have also been carried out for the title compounds. The computed absorption spectral data of the title compounds are in good agreement with the experimental data, thus allowing an assignment of the UV spectra. The HOMO and LUMO molecular orbitals, excitation energies and oscillator strengths for the dyes have also been calculated and presented.

Thermostable Broad Band Polarizing PVA-Film: Theoretical and Experimental Investigations

In the present work, for the first time on the basis ofpoly （vinyl alcohol） （PVA）, 2- （4-dimethylaminostyryl）-l-ethylquinolinium iodide （quinaldine red （QR）） and trisodium （4E）-5-oxo- 1-（4-sulfonatophenyl）-4-[（4-sulfonatophenyl）hydrazono]-3 pyrazolecarboxylate （tartrazine （T））, thermostable polarizing film in a wide range of spectra （λmax=394-511 nm） with polarization efficiency （PE） = 98% in absorption maximum and stretching degree （Rs） = 3.5 was developed. The basic spectral-polarization parameters （polarization efficiency and transmittance） of oriented colored PVA-films were measured and discussed. During the work it was found that oriented PVA-films are the phenomenon of anisotropy of thermal conductivity （λ｜/λ⊥）. It is a very important parameter for the development of thermostable PVA-polarizing films. For the first time quantum-chemical calculations using density functional theory （DFT） approach for structural analysis and electronic spectrum of the QR were carried out via the B3LYP/dgdzvp and TDB3LYP/dgdzvp methods. Interpretation of absorption strips in visible region of spectrum was also reported. The excitation energies, electronic transitions and oscillator strengths for the studied structures have also been calculated （B3LYP/dgdzvp）. The NBO analysis and Mulliken atomic charges of the QR were carried out.

Antitumor and Antioxidant Activities of the New Anthraquinone Derivatives: Synthesis, DPPH, ABTS, Biological and DFT Investigations

In the given research,for the first time the molecular structures of four new anthraquinone derivatives have been predicted and investigated by using Density Functional Theory(DFT/M052X/MidiX)in water.After quantum-chemical calculations the title compounds have been synthesized.The M052X/MidiX method has been employed to obtain Bond Dissociation Enthalpy(BDE),Mulliken Charges,NBO analysis,Ionization Potential(IP),Electron Affinities(EA),HOMO and LUMO energies,Hardness(η),Softness(S),Electronegativity(μ),Electrophilic Index(ω),Electron Donating Power(ω^-),Electron Accepting Power(ω^+)and Energy Gap(Eg) in order to infer scavenging activity of the four new synthesized anthraquinone derivatives(Sm-3,Sm-4,Sm-7,Sm-10).Comparative analysis of BDE of Sm-3,4,7,10 indicates the weal antioxidant potential of these structures.These molecules have high antioxidant potential due to the planarity and formation of intramolecular hydrogen bonds.Experimental investigations establish high antioxidant and antitumor activities of the synthesized anthraquinone derivatives.

Synthesis, Crystal Structure and Theoretical Calculations of N-Benzyl-1-(5-(3-chlorophenyl)-1,3,4-oxadiazol-2-yl)cyclopentanamine

N-benzyl-1-（5-（3-chlorophenyl）-1,3,4-oxadiazol-2-yl）cyclopentanamine was synthesized via one-pot reaction of appropriate benzylamine, cyclopentanone,（N-isocyanimino）triphenylphosphorane and m-chlorobenzoic acid. The quantum theoretical calculations for crystal structure were performed by density functional theory（DFT/B3LYP/6-311＋G＊）. From the optimized structure, geometric parameters were obtained and experimental measurements were compared with the calculated data. Frontier molecular orbitals（FMOs）, total density of states（DOS）, molecular electrostatic potential（MEP）, molecular properties, natural charges, NMR parameters and NBO analysis for the product were investigated by theoretical calculations.

DFT Study of Physisorption Effect of the Curcumin on CNT(8,0-6) Nanotube for Biological Applications

In the given work the adsorption properties of molecule curcumin((1 E,6 E)-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione) on CNT(8,0-6) nanotube were investigated by the density functional theory(DFT) in the solvent water for the first time. The non-bonded interaction effects of compounds curcumin and CNT(8,0-6) nanotube on the electronic properties, UV/Vis spectra, chemical shift tensors and natural charges were determined and discussed. The electronic spectra of the compound curcumin and the complex CNT(8,0-6)/curcumin in the solvent water were calculated by time dependent density functional theory(TD-DFT) for investigation of the maximum wavelength value of molecule Curcumin before and after the non-bonded interaction with the CNT(8,0-6) nanotube and molecular orbitals involved in the formation of absorption spectrum of the complex CNT(8,0-6)/curcumin at maximum wavelength.

Optimization, Spectroscopic(FT-IR, Excited States, UV/Vis) Studies, FMO, ELF, LOL, QTAIM and NBO Analyses and Electronic Properties of Two New Pyrimidine Derivatives

In the given research,the molecular structures of two new compounds,4-((E)-3-(dimethylamino)styryl)-6-((E)-4-(dimethylamino)styryl)pyrimidine-2-amine(PM-1)and N-(4-((E)-3-(dimethylamino)styryl)-6-((E)-4-(dimethylamino)styryl)pyrimidine-2-yl)-4,6-dichloro 1,3,5-1,3,5-triazin-2-amine(PM-2),have been studied with the use of density functional theory(DFT/B3LYP/MidiX)in dimethylformamide(DMF)for the first time.The electronic spectra of the new compounds in a DMF solvent were carried out by temporally dependent density functional theory(TD-DFT)method.The computed absorption spectral data of the title compounds are in good agreement with the experimental data,thus allowing an assignment of the UV/Vis spectra.The equilibrium geometry,the HOMO and LUMO molecular orbitals,excitation energies,oscillator strengths and Natural Bond Orbital(NBO)analysis for the molecules have also been calculated and presented.FT-IR spectra of the title molecules are recorded and discussed.The electron location function(ELF),localized orbital locator(LOL)and quantum theory of atoms in molecules(QTAIM)analyses were also carried out.On the basis of polyvinyl alcohol(PVA)and synthesized molecules,polarizer for UV/Vis region of the spectrum has been developed.

Theoretical Study of Interaction between Apalutamide Anticancer Drug and Thymine by DFT Method

The main purpose of this study is a better comprehension of the non-bonded interaction between an anticancer drug apalutamide and deoxyribonucleic acid(DNA).In the prese nt work,the in teraction between an ticancer drug apalutamide and one of the DNA bases called 2,-deoxythymidine 5,-monophosphate(thymine)by Density Functional Theory(DFT)calculations in the solvent water has been investigated for the first time.The non-bonded interaction effects of the molecule apalutamide with thymine on the electronic properties,chemical shift tensors and natural charges have been also detected.The natural bond orbital(NBO)analysis was performed for determining the role of electron donor and acceptor of the molecules apalutamide and thymine at the complex thymine/apalutamide.Both Electron location function(ELF),localized orbital locator(LOL)and quantum theory of atoms in molecules(QTAIM)analysis were carried out in order to determine the chemical bond nature in the investigated compounds.The values of ELF and LOL parameters for the selected bonds are small,which confirms the non-covalent character of these bonds in nature.The electronic spectra of the apalutamide drug,thymine and complex thymine/apalutamide in solvent water were calculated by Time Dependent Density Functional Theory(TD-DFT)for the investigation of interaction effect;Non-bonded interaction between the compound apalutamide and thymine has changed the value of λmax.

Theoretical Study of Adsorption Behavior of Vemurafenib Drug over BNNT(5,5-9) as a Factor of Drug Delivery: a DFT Study

In this research,a density functional theory(DFT)calculation was performed for investigation adsorption behavior of the anticancer drug Vemurafenib on BNNT(5,5-9)by using the M06-2X/6-31 G*level of theory in the solvent water.The electronic spectra of the Vemurafenib drug,BNNT(5,5-9)and complex BNNT(5,5-9)/Vemurafenib in solvent water were calculated by Time Dependent Density Functional Theory(TD-DFT)for the study of adsorption effect.The non-bonded interaction effects of the Vemurafenib drug with BNNT(5,5-9)on the electronic properties,natural charges and chemical shift tensors have been also detected.The results display the change in title parameters after process adsorption.According to the natural bond orbital(NBO)results,the molecule Vemurafenib and BNNT(5,5-9)play as both electron donor and acceptor at the complex BNNT(5,5-9)/Vemurafenib.On the other hand,the charge transfer occurs between the bonding,antibonding or nonbonding orbitals in two molecules drug and BNNT.As a consequence,BNNT(5,5-9)can be considered as a drug delivery system for the transportation of Vemurafenib as anticancer drug within the biological systems.