Detailed quantum mechanical, molecular docking, QSAR prediction, photovoltaic light harvesting efficiency analysis of benzil and its halogenated analogues

The superiority of isomeric, fluorination and curtailed π-conjunction on A-D-A type acceptors for organic photovoltaics

The performance of organic solar cell (OSC) devices has been significantly enhanced by the dramatic evolution of A-D-A type non-fullerene acceptors (NFAs). Nevertheless, the structure-property-performance relationship of NFAs in the OSC device is unclear. Here, the intrinsic design factors of isomeric, fluorination and π-conjunction curtailing on the photophysical properties of benzodi (thienopyran) (BDTP) (named NBDTP-M, NBDTTP-M, NBDTP-Fin, and NBDTP-Fout)-based NFAs are discussed. The results show that fluorination on the terminal group of NBDTP-Fout could effectively decrease the highest occupied orbital (HOMO) energy level and the lowest unoccupied orbital (LUMO) energy level. And the long π-conjugated donor unit for NBDTTP-M could increase the HOMO energy level and bring a small HOMO-LUMO energy bandgap. Meanwhile, the substitution of external oxygen atoms and the fluorine atoms in the terminal group could introduce positive changes to the electrostatic potential of the NBDTP-Fout, favouring the charge separation at the donor/acceptor interface. Moreover, the structural design of external oxygen atom substitution, fluorination on the terminal group and curtailed π-conjugated donor unit could decrease the electron vibration-coupling of exciton diffusion, exciton dissociation and electronic transfer processes. The suppression of the exciton decay and charge recombination in those high-performance NFAs indicate that the investigated molecular designs could be effective for further improvement of OSCs.

Elucidating the Advancement in the Optoelectronics Characteristics of Benzoselenadiazole-Based A2-D-A1-D-A2-Type Nonfullerene Acceptors for Efficient Organic Solar Cells

The potential applications of nonfullerene acceptors (NFAs) such as tunable band gaps, improved charge separation, wide-range absorption, enhanced power conversion efficiency, and operational stability make them highly favorable for organic photovoltaic applications. Herein, we designed eight novel structurally modified nonfused benzoselenadiazole (BSe)-based A2-D-A1-D-A2-type NFAs for efficient organic solar cells (OSCs). These newly modeled BSe-based NFA series contain BSe as the central core. We employed strong electron-withdrawing moieties at terminal acceptor A2 to further enhance the optical, optoelectronics, and photovoltaic characteristics of OSCs. These designed molecules (HNM1-HNM8) along with the synthetic reference molecule (HNM) were thoroughly characterized by using efficient and advanced quantum chemical simulation approaches. Thus, to ascertain the enhancement of both optical and photochemical response, a thorough density functional theory (DFT) study was carried out using the M062X level in association with the 6-31G(d,p) basis set. All of the investigated molecules (HNM1-HNM8) had their excited states calculated using the time-dependent density functional theory method. The newly designed molecules (HNM1-HNM8) presented narrower band gaps, improved absorption and optoelectronics properties, and reduced excitation and binding energies. The electrostatic potential, density of states, transition density matrix, ionization potential, and electron affinity analysis of this newly designed (HNM1-HNM8) series revealed a strong coherence with those of the reference HNM molecule. Electron density difference mapping allowed us to visualize the spatial movement of electrons between the donor and acceptor molecules during excitation. This insight helps us to understand the efficiency of charge separation and recombination processes that are critical for the performance of organic photovoltaics. The reorganization energy and charge transfer analysis suggests that HNM1-HNM8 molecules could act as NFAs for organic photovoltaic applications to enhance their efficiency further. The donor: acceptor charge transfer analysis was also carried out, which revealed that the PTB7-Th:HNM2 donor:acceptor complex shows a great charge transportation process at the donor-acceptor interface. Moreover, the photovoltaic analysis shows that the designed (HNM1-HNM8) NFA series has a great potential to produce improved open-circuit voltage and fill factor values, which may be helpful in enhancing the overall PCEs of the OSCs.

Engineering of the Central Core on DBD-Based Materials with Improved Power-Conversion Efficiency by Using the DFT Approach

Developing proficient organic solar cells with improved optoelectronic properties is still a matter of concern. In the current study, with an aspiration to boost the optoelectronic properties and proficiency of organic solar cells, seven new small-molecule acceptors (Db1-Db7) are presented by altering the central core of the reference molecule (DBD-4F). The optoelectronic aspects of DBD-4F and Db1-Db7 molecules were explored using the density functional theory (DFT) approach, and solvent-state calculations were assessed utilizing TD-SCF simulations. It was noted that improvement in photovoltaic features was achieved by designing these molecules. The results revealed a bathochromic shift in absorption maxima (λmax) of designed molecules reaching up to 776 nm compared to 736 nm of DBD-4F. Similarly, a narrow band gap, low excitation energy, and reduced binding energy were also observed in newly developed molecules in comparison with the pre-existing DBD-4F molecule. Performance improvement can be indicated by the high light-harvesting efficiency (LHE) of designed molecules (ranging from 0.9992 to 0.9996 eV) compared to the reference having a 0.9991 eV LHE. Db4 and Db5 exhibited surprisingly improved open-circuit voltage (V OC) values up to 1.64 and 1.67 eV and a fill factor of 0.9198 and 0.9210, respectively. Consequently, these newly designed molecules can be considered in the future for practical use in manufacturing OSCs with improved optoelectronic and photovoltaic attributes.

Investigation of the interaction of thymine drugs with Be12O12 and Ca12O12 nanocages: A quantum chemical study

Based on the DFT in a Wb97xd/6-311+G* level of theory, the interaction of thymine derivatives with Be12O12 and Ca12O12 nanocages was investigated. It was found that adsorption energies of thymine molecules on the Be12/Ca12-O12 surface was around -43.16, -60.06 and -29.62, -50.71, -45.95, -30.27 kcal/mol, for thymine (TH1), 1-amino thymine (TH2) and thymine glycol (TH3), respectively and this result supported the drug's adsorption. Additionally, according to the FMOs and MEP studies, a charge transfer from TH's to nanocages. Additionally, both molecular orbitals demonstrate that the LUMO and HOMO are primarily found on the BeO's surface.

Exploring the Electronic, Optical, and Charge Transfer Properties of A-D-A-Type IDTV-ThIC-Based Molecules To Enhance Photovoltaic Performance of Organic Solar Cells

Improving the charge mobility and optoelectronic properties of indacenodithiophene-based small molecule acceptors is a key challenge to improving overall efficiency. In this current research, seven newly designed molecules (DT1-DT7) comprising the indacenodithiophene-based core are presented to tune energy levels, enhance charge mobility, and improve the photovoltaic performance of IDTV-ThIC molecules via density functional theory. All the molecules were designed by end-capped modification by substituting terminal acceptors of IDTV-ThIC with strong electron-withdrawing moieties. Among all the examined structures, DT1 has proved itself a superior molecule in multiple aspects, including higher λmax in chloroform (787 nm) and gaseous phase (727 nm), narrow band gap (2.16 eV), higher electron affinity (3.31 eV), least excitation energy (1.57 eV), and improved charge mobility due to low reorganization energy and higher excited state lifetime (2.37 ns) when compared to the reference (IDTV-ThIC) and other molecules. DT5 also showed remarkable improvement in different parameters, such as the lowest exciton binding energy (0.41 eV), leading to easier charge moveability. The improved open-circuit voltage of DT4 and DT5 makes them proficient molecules exhibiting the charge transfer phenomenon. The enlightened outcomes of these molecules can pave a new route to develop efficient organic solar cell devices using these molecules, especially DT1, DT4, and DT5.

Synthesis and Biological Evaluation of Octahydroquinazolinones as Phospholipase A2, and Protease Inhibitors: Experimental and Theoretical Exploration

Phospholipase A2 (PLA2) promotes inflammation via lipid mediators and releases arachidonic acid (AA), and these enzymes have been found to be elevated in a variety of diseases, including rheumatoid arthritis, sepsis, and atherosclerosis. The mobilization of AA by PLA2 and subsequent synthesis of prostaglandins are regarded as critical events in inflammation. Inflammatory processes may be treated with drugs that inhibit PLA2, thereby blocking the COX and LOX pathways in the AA cascade. To address this issue, we report herein an efficient method for the synthesis of a series of octahydroquinazolinone compounds (4a-h) in the presence of the catalyst Pd-HPW/SiO₂ and their phospholipase A2, as well as protease inhibitory activities. Among eight compounds, two of them exhibited overwhelming results against PLA2 and protease. By using FT-IR, Raman, NMR, and mass spectroscopy, two novel compounds were thoroughly studied. After carefully examining the SAR of the investigated compounds against these enzymes, it was found that compounds (4a, 4b) containing both electron-donating and electron-withdrawing groups on the phenyl ring exhibited higher activity than compounds with only one of these groups. DFT studies were employed to study the electronic nature and reactivity properties of the molecules by optimizing at the BLYP/cc-pVDZ. Natural bond orbitals helped to study the various electron delocalizations in the molecules, and the frontier molecular orbitals helped with the reactivity and stability parameters. The nature and extent of the expressed biological activity of the molecule were studied using molecular docking with human non-pancreatic secretory phospholipase A2 (hnps-PLA2) (PDB ID: 1DB4) and protease K (PDB ID: 2PWB). The drug-ability of the molecule has been tested using ADMET, and pharmacodynamics data have been extracted. Both the compounds qualify for ADME properties and follow Lipinski's rule of five.

Novel N-benzyl-2-oxo-1,2-dihydrofuro [3,4-d]pyrimidine-3(4H)-carboxamide as anticancer agent: Synthesis, drug-likeness, ADMET profile, DFT and molecular modelling against EGFR target

A novel compound N-benzyl-2-oxo-1,2-dihydrofuro [3,4-d]pyrimidine-3(4H)-carboxamide (DHFP) was synthesized by addition, rearrangement, and intramolecular cyclization reactions. The three-dimensional geometry of DHFP has been determined by density functional theory calculations in the gas phase. Thus, the geometrical properties of DHFP such as the bond lengths, bond angles, and dihedral bond angles have been determined in the optimized molecular configuration. Also, the HOMO-LUMO energies were calculated. The charge distribution of the DHFP has been calculated by Natural Population Analysis (NPA) approach. NMR and FTIR spectra were calculated and compared with their experimental corresponding to confirm the synthesis of the DHFP. The anticancer activities of the DHFP were also determined on human colon cancer (HT29) and prostate cancer (DU145) cell lines. Molecular docking studies of the DHFP with EGFR tyrosine kinase, which is responsible for cancer cell proliferation and growth, were performed and it was observed that docking interaction took place. The DHFP has the potential to be a drug, as it is determined that DHFP obeys Lipinski's five rules, can cross the blood-brain barrier, and can be rapidly absorbed from the gastrointestinal wall.

Modeling the structure and reactivity landscapes of a pyrazole-ammonium ionic derivative using wavefunction-dependent characteristics and screening for potential anti-inflammatory activity

Spectroscopic investigations of 1-phenyl -2,3-dimethyl-5-oxo-1,2-dihydro-1H-pyrazol-4-ammonium 2[(2-carboxyphenyl) disulfanyl]benzoate (PACB) reported experimentally and theoretically. NH-O interaction is observed and there is a very large downshift for NH-O stretching frequency. Reactive sites are identified from the chemical and electronic properties. For PACB the maximum repulsion was around H33, H55 and H57 atom. LOL shows red regions between C-C and blue around C atoms are surrounded by a delocalized electron cloud. The red ring is a hallmark of electron density depletion from the NCI plot due to electrostatic repulsion and its existences suggests that coordination sphere for PACB is minimally strained around the central ion. Atomic contact energy values and high score of the docking results obtained propose that, PACB may have inhibitory properties and have a significant function in pharmacological chemistry. Molecular dynamics simulation was performed to validate the stability of the title compound with the Bovine thrombin-activatable fibrinolysis inhibitor protein.Communicated by Ramaswamy H. Sarma.

Schiff Bases from α-ionone with Adenine, Cytosine, and l-leucine Biomolecules: Synthesis, Structural Features, Electronic Structure, and Medicinal Activities

Tea is a very important source of the terepenoid [Formula: see text]-ionone, which is much appreciated as a medicinal beverage. Schiff bases are a very important class of organic compounds usually formed by the condensation of carbonyl compounds with amines. [Formula: see text]-ionone is a carbonyl terpenoid obtained from Schiff bases on condensation with nucleobases like adenine and cytosine and the amino acid [Formula: see text]-leucine. We synthesized these three Schiff bases and characterized them using UV, FTIR, and H1 and C13-NMR spectra. The molecules were optimized using B3LYP/6-311+G(2d,p) level followed by the simulation of FT-IR spectra, of which the simulated and experimental spectra showed complete agreement. The UV spectra were simulated using TD-DFT, and the electronic excitations were carefully analyzed. Natural bond orbitals provided an analysis of the stability of the compound, which is supplemented by the data from frontier molecular orbital analysis. Detailed wavefunction analysis is reported which predicts the active centers, reactivity profile, and the extent of non-covalent interactions. PASS indicated that compounds show antieczemic properties and antiarthritic properties, which is confirmed with the help of molecular docking results.

Adsorption of adipic acid in Al/B-N/P nanocages: DFT investigations

Drug delivery clusters based on nanocages recently have been the most capable to study. Adipic acid (ADPA) interaction mechanism over nanocages of X(Al/B)12Y(N/P)12 was investigated. We analyzed various electronic, chemical, and spectroscopic properties with nanocages of the adsorbed ADPA molecule. Adsorption energies were calculated to study the adsorption of ADPA with nanocages. Raman enhanced surface scattering is used to track the drug as an effective approach to vibrational spectroscopy. Detection of the drug has been investigated using the SERS properties of nanocages. Title drug acts as a donor of electrons and adsorbs at the electrophilic site of nanocages. Variations in chemical descriptors to recognize the sensing property of ADPA-nanocages are also noted. Analysis of various properties explains enhancement which makes it possible to detect the drug in other products. • Interaction of adipic acid with fullerene-like metal nanocages • Enhancement of spectral properties • Changes in charge transfer values in nanocage-drug system • Docking studies identify the drug delivery property.

Excited-state electronic properties, structural studies, noncovalent interactions, and inhibition of the novel severe acute respiratory syndrome coronavirus 2 proteins in Ripretinib by first-principle simulations

Ripretinib is a recently developed drug for the treatment of adults with advanced gastrointestinal stromal tumors. This paper reports an attempt to study this molecule by electronic modeling and molecular mechanics to determine its composition and other specific chemical features via the density-functional theory (DFT), thereby affording sufficient information on the electronic properties and descriptors that can enable the estimation of its molecular bioactivity. We explored most of the physico-chemical properties of the molecule, as well as its stabilization, via the studies of the natural bond orbitals and noncovalent interactions. The electronic excitation, which is a time-dependent process, was examined by the time-dependent DFT with a CAM-B3LYP functional. The molecular docking study indicated that Ripretinib strongly docks with three known novel severe acute respiratory syndrome coronavirus 2 (SARS-n-CoV-2) proteins with a reasonably good docking score.

DFT computational study towards investigating psychotropic drugs, promazine and trifluoperazine adsorption on graphene, fullerene and carbon cyclic ring nanoclusters

Detection and qualification process related to impurities assume importance in pharmacological drug development programmes and the present article gives the structural and spectral characterisation of phenothiazine derivatives, promazine (PME) and trifluoperazine (TPE) and their self-assembly with graphene/fullerene/carbon ring (CG/CF/CR) systems theoretically. The investigation of adsorption behaviour of these compounds can provide valuable information about its reactivity, electronic and structural properties. Three-dimensional electrostatic potential diagrams were mapped. The frontier orbital energies and energy band gaps of the molecules were computed. Delocalization of charge density between the bonding or lone pair and antibonding orbitals is calculated by NBO analysis. Docking was executed to investigate binding areas of chemical compounds. Bioactivity scores show that the pharmacokinetic and pharmacological properties of the ligands are appropriate leading to be considered potential drug agents. The obtained theoretical wavenumber results of the present study were fully compatible with the experimental results.

Spectroscopic and computational study of chromone derivatives with antitumor activity: detailed DFT, QTAIM and docking investigations

Theoretical investigations of three pharmaceutically active chromone derivatives, (E)-3-((2,3,5,6-tetrafluorophenyl)hydrazono)methyl)-4H-chromen-4-one (TPC), (E)-3-((2-(2,4,6-trifluorophenyl)hydrazono)methyl)-4H-chromen-4-one (FHM) and(E)-3-((2-(perfluorophenyl)hydrazono)methyl)-4H-chromen-4-one (PFH) are reported. Molecular geometries, vibrational spectra, electronic properties and molecular electrostatic potential were investigated using density functional theory. Quantum theory of atoms in molecules (QTAIM) study shows that the maximum of ellipticity parameters in the existing bonds in TPC, FHM and PFH, attributes to the bonds involving in aromatic region points toward the π-bond interactions in the molecules. Based on energy gap (1.870, 1.649 and 1.590 eV) and electrophilicity index (20.233, 22.581 and 23.203 eV) values of TPC, FHM and PFH, we can conclude that all molecules have more biological activity. The molecular electrostatic potential maps were calculated to provide information on the chemical reactivity of the molecule and also to describe the intermolecular interactions. All these studies including docking studies, help a lot in determining the biological activities of chromone derivatives. Activities of chromone derivatives are compared with 5-fluorouracil and azathioprine (antitumor, antiproliferative standards) and were found to be higher than reference ones.

Utilization of O/S-doped graphene nanoclusters for ultrasensitive detection of flurane derivatives-DFT investigations

Nanocluster based drug delivery systems are very useful in modern medical treatment and interaction mechanism of desflurane (DES), isoflurane ISO), sevoflurane (SEV) over carboxyl substituted graphene-doped with O and S atoms were investigated in the present study. Different electronic and chemical properties of adsorbed desflurane, isoflurane and sevoflurane with nanoclusters are analyzed. To track the drugs, SERS is used as an efficient method and drug's detection was analyzed using SERS. DES's energy over GQD-S is greater than that over GQD-O nanocluster and for ISO and SEV, adsorption energies over the O/S nanoclusters are same. The title drugs work on the reactives sites and got adsorbed. For ISO, there is an increase in fluorine atom charges and for DES and SEV, the fluorine atom charge decreases due to adsorption in both O/S nanoclusters. Changes in chemical descriptors are identified for the sensing property of drug-nanoclusters.Communicated by Ramaswamy H. Sarma.

Cocrystals of hydrochlorothiazide with picolinamide, tetramethylpyrazine and piperazine: quantum mechanical studies, docking and modelling of the photovoltaic efficiency for DSSC

Cocrystals are of immense applications in crystal engineering and pharmaceutical chemistry. Hydrochlorothiazide is found to form cocrystals with picolinamide (H1), tetramethylpyrazine (H2) and piperazine (H3). It was characterized using IR spectra, and quantum mechanical calculations for geometry and other properties. Frontier orbital energies are used to predict the energy properties and model the possible charge transfer between the constituents of the cocrystal. The frontier molecular orbital analysis indicates chemical reactivity and bioactivity of the cocrystals. The MEP surface reveals the various reactive surfaces in the cocrystal system, which is very important in deciding various biological activities. The UV-Vis spectra show the possible electronic transitions of the molecules. Simulated electronic spectra using TDDFT method with CAM-B3LYP functional were used to investigate the suitability of the cocrystals to be used in DSSC. Moreover, the molecular docking analysis proves that the cocrystals can act as potential inhibitors and paves the way for developing effective drugs.

Structural study of letrozole and metronidazole and formation of self-assembly with graphene and fullerene with the enhancement of physical, chemical and biological activities

Letrozole and metronidazole are two commonly used drugs for the management of breast cancer and parasitic infections, respectively. This manuscript attempts to study their structure, geometry, search for stable conformers using relaxed potential energy scan, spectral properties, quantum mechanical properties like energy and reactivity descriptors, intra molecular electron transfer properties, non-linear properties etc using various computational tools. It is found that these compounds will form a self-assembly with graphene sheets and fullerenes and exhibit a surface-enhanced Raman spectra and enhancement in non-linear optical properties when compared to the single molecule. The electronic absorption behavior of the compounds was studied using TD-DFT method. Global chemical reactivity descriptors and activity sites toward electrophilic and nucleophilic attack have been discussed. Studies of intra molecular electron transfer gave information about the relative stability of the compounds. Molecular docking studies indicate that the pure compounds and their self-assemblies with graphene have excellent biological activities.Communicated by Ramaswamy H. Sarma.

Detailed molecular structure (XRD), conformational search, spectroscopic characterization (IR, Raman, UV, fluorescence), quantum mechanical properties and bioactivity prediction of a pyrrole analogue

Pyrroles are an exciting class of organic compounds with immense medicinal activities. This manuscript presents the structural and quantum mechanical studies of 1-(2-aminophenyl) pyrrole using X-Ray diffraction and various spectroscopic methods like Infra-Red, Raman, Ultra-violet and Fluorescence spectroscopy and its comparison with theoretical simulations. The single-crystal X-ray diffraction values and optimized geometry parameters also were within the agreeable range. A fully relaxed potential energy scan revealed the stability of the possible conformers of this molecule. We present the density functional theory results and assignment of the vibrational modes in the infrared spectrum. The experimental and scaled simulated vibrations matched when density functional theory simulations (B3LYP functional with 6–311++G∗∗). The electronic spectrum was simulated using time-dependent density functional theory with CAM-B3LYP functional in dimethylsulphoxide solvent. The fluorescence spectrum of the compound was studied at different excitation wavelengths in the dimethylsulphoxide solvent. The stability of the molecule by intramolecular electron transfer by hyperconjugation was studied with the natural bond orbital analysis. Frontier molecular orbitals and molecular electrostatic potentials of the compound gave an idea about the reactive behaviour of the compounds. Prediction of activity spectral studies followed by docking analysis indicated that the molecule is active against arylacetonitrilase inhibitor.