Crystal to Hydrogel Transformation in S-Benzyl-L-Cysteine-Containing Cyclic Dipeptides - Nanostructure Elucidation and Applications.

Cyclic dipeptides (CDPs) are crucial building blocks for a range of functional nanomaterials due to their simple chemical structure and high molecular stability. In this investigation, we synthesized a set of S-benzyl-L-cysteine-based CDPs (designated as P1-P6) and thoroughly examined their self-assembly behavior in a methanol-water solvent to elucidate the relationship between their structure and gelation properties. The hydrophobicity of the amino acids within the CDPs was gradually increased. The present study employed a comprehensive array of analytical techniques, including NMR, FT-IR, AFM, thioflavin-T, congo-red CD, X-ray crystallography, and biophysical calculations like Hirshfield Surface analysis and DFT analysis. These methods revealed that in addition to hydrogen bonding, the hydrophobic nature of the amino acid side chain significantly influences the propensity of CDPs to form hydrogels. Each CDP yielded distinct nanofibrillar networks rich in ß-sheet structures, showcasing unique morphological features. Moreover, we explored the practical application of these CDP-based hydrogels in water purification by utilizing them to remove harmful organic dyes from contaminated water. This application underscores the potential of CDPs in addressing environmental challenges, offering a promising avenue for the future development of these materials in water treatment technologies.

Entropy-Enthalpy Compensation in Solvent Geometry Regulated Supramolecular Polymerization of Luminescent Napthalimide via a Non-Cooperative, Isodesmic Mechanism.

Supramolecular polymers of π-conjugated systems are an important class of materials with fascinating functions and properties originated from the dynamic behavior and highly ordered molecular organizations. Here, a donor-π-acceptor based functionalized luminescent napthalene monoimide (NMI) undergoes J-type self-assembly by non-covalent interactions via a non-cooperative, isodesmic mechanism to form supramolecular 1D nanowire. The fundamental insights into the thermodynamics regulating the supramolecular polymerization were derived through the fitting of the isodesmic model to variable temperature UV/Vis data in linear (dodecane) and nonliner hydrocarbon (decalin) based solvents. This shows a significant role of entropy-enthalpy compensation in solvent geometry-regulated formation and stabilization of supramolecular polymer. Furthermore, we have quantitively estimated the influence of solvent geometry and found that NMI forms stronger self-assembly and spontaneous gel in linear hydrocarbon based solvent compared to nonliner one and thereby substantially increases the degree of polymerization in linear hydrocarbon solvent (dodecane). This is accredited to the effective influence of the linear hydrocarbon solvent molecules in the polymerization process by favourable van der waals interactions with the peripheral alkyl chains of the NMI monomers in contrast to unfavourable interaction of nonliner hydrocarbon solvent due to geometry mismatch.

Urea-Promoted Neat Synthesis of Fused Dihydroisoquinolines and Disubstituted Pyridines: A Mechanistic Observation with Molecular-Sensing Studies.

An efficient and short synthesis of fused dihydroisoquinolines, diaryl substituted pyridine derivatives in good to high yields has been established by using an environmentally safe, solvent-metal-oxidant-free tandem approach. In this article, we discuss how the electrocyclic reaction is more pronounced in the solid phase in the presence of urea, whereas the typical aza-Michael addition is more prominent in presence of arylamine in the solution phase for 3-(2-formylcycloalkenyl)acrylic ester derivative substrates. The wide range of substrates and urea-promoted neat synthesis made our approach more significant in medical and also analytical science. Moreover, an isoquinoline alkaloid decumbenine B analogue has been synthesized by using our newly developed neat methodology. We have also investigated the photophysical properties of the synthesized fused dihydroisoquinoline derivatives. One of the synthesized molecules was used as a sensor for the selective detection of toxic picric acid. Therefore, the effective neat synthesis and molecular sensing applications of these compounds made our approach more exciting in the field of heterocyclic chemistry.

Solvent Geometry Regulated J- and H-Type Aggregates of Photoswitchable Organogelator: Phase-Selective Thixotropic Gelation and Oil Spill Recovery.

We demonstrate supramolecular polymerization and formation of 1D nanofiber of azobenzene based organogelator (AZO-4) in cyclic hydrocarbon solvents (toluene and methylcyclohexane). The AZO-4 exhibits J- and H-type aggregates in toluene: MCH (9 : 1) and MCH: toluene (9 : 1) respectively. The type of aggregate was governed by the geometry of the solvents used in the self-assembly process. The J-type aggregates with high thermal stability in toluene is due to the enhanced interaction of AZO-4 π- surface with the toluene π-surface, whereas H-aggregate with moderate thermal stability in MCH was due to the interruption of the cyclic hydrocarbon in van der Waals interactions of peripheral chains of AZO-4 molecule. The light induced reversible photoisomerization is observed for both J- and H-aggregates. The macroscopic property revealed spontaneous and strong gelation in toluene preferably due to the strong interactions of the AZO-4 nanofibers with the toluene solvent molecules compared to the MCH. The rheological measurements revealed thixotropic nature of the gels by step-strain experiments at room temperature. The thermodynamic parameter (ΔHm) of gel-to-sol transition was determined for all the gels to get more insight into the gelation property. Furthermore, the phase selective gelation property was extended to the oil spill recovery application using diesel/water and petrol/water mixture.

Live-Cell Mitochondrial Targeted NIR Fluorescent Covalent Labeling of Specific Proteins Using a Dual Localization Effect.

Here, our designed water-soluble NIR fluorescent unsymmetrical Cy-5-Mal/TPP+ consists of a lipophilic cationic TPP+ subunit that can selectively target and accumulate in a live-cell inner mitochondrial matrix where a maleimide residue of the probe undergoes faster chemoselective and site-specific covalent attachment with the exposed Cys residue of mitochondrion-specific proteins. On the basis of this dual localization effect, Cy-5-Mal/TPP+ molecules remain for a longer time period even after membrane depolarization, enabling long-term live-cell mitochondrial imaging. Due to the adequate concentration of Cy-5-Mal/TPP+ reached in live-cell mitochondria, it facilitates site-selective NIR fluorescent covalent labeling with Cys-exposed proteins, which are identified by the in-gel fluorescence assay and LC-MS/MS-based proteomics and supported by a computational method. This dual targeting approach with admirable photostability, narrow NIR absorption/emission bands, bright emission, long fluorescence lifetime, and insignificant cytotoxicity has been shown to improve real-time live-cell mitochondrial tracking including dynamics and interorganelle crosstalk with multicolor imaging applications.

Arylative Methylation of 2,3-Dihydropyrazines and Pyrazinones Using Dimethyl Sulfoxide as a C1 Source.

Divergent synthesis of α-C-H methylated pyrazines and pyrazinones using dimethyl sulfoxide as a nonconventional methylating agent under metal-free conditions was reported. Dimethyl sulfoxide-coordinated bromine cation pools generated from the treatment of dimethyl sulfoxide and 1,2-dibromoethane undergo Pummerer-type fragmentation to afford an electrophilic methyl(methylene)sulfonium ion for reaction with a carbon nucleophile followed by aromatization to afford α-methylated pyrazines and pyrazinones.

Synthesis of Multifused Pyrrolo[1,2-a]quinoline Systems by Tandem Aza-Michael-Aldol Reactions and Their Application to Molecular Sensing Studies.

Herein, we have presented a weak acid-promoted tandem aza-Michael-aldol strategy for the synthesis of diversely fused pyrrolo[1,2-a]quinoline (tricyclic to pentacyclic scaffolds) by the construction of both pyrrole and quinoline ring in one pot. The described protocol fabricated two C-N bonds and one C-C bond in the pyrrole-quinoline rings which have been sequentially formed under transition-metal-free conditions by the extrusion of eco-friendly water molecules. A ketorolac drug analogue has been synthesized following the current protocol, and one of the synthesized tricyclic pyrrolo[1,2-a]quinoline fluorophores has been used to detect highly toxic picric acid via the fluorescence quenching effect.

Crystallography-based exploration of non-covalent interactions for the design and synthesis of coumarin for stronger protein binding.

Protein molecules are a good target for the inhibition or promotion of biological processes. Different methods like QSAR and molecular docking have been developed to accurately design small binder molecules for target proteins. An alternative model has been developed wherein a statistical method is used to find the propensity of different non-covalent interactions between small molecules and amino acid residues of the protein. The results give hints as to the choice of substituents required at the SM to strongly bind to a protein. In this case, 75 different types of proteins bound with coumarin derivatives have been investigated and the non-covalent interactions observed between the basic coumarin moiety and amino acids have been analyzed. Density functional theory (DFT) calculations were used to identify the electronic features of coumarin to understand the feasibility of the observed non-covalent interactions and to find appropriate groups that can modulate these interactions. The binding affinity towards a protein (ß-lactoglobulin (BLG)) and the stability of the protein complex have been investigated through docking and molecular dynamics of 100 ns, respectively. The modeled compounds were synthesized and investigated with regards to their interactions with the model carrier protein. The thermodynamics of the interactions were also investigated and the binding is governed by the Le Chatelier principle.

A family of amphiphilic dioxidovanadium(V) hydrazone complexes as potent carbonic anhydrase inhibitors along with anti-diabetic and cytotoxic activities.

A family of dioxidovanadium(V) complexes (1-4) of the type [Na(H2O)x]+[VVO2(HL1-4)]- (x = 4, 4.5 and 7) where HL2- represents the dianionic form of 2-hydroxybenzoylhydrazone of 2-hydroxyacetophenone (H2L1, complex 1), 2-hydroxy-5-methylacetophenone (H2L2, complex 2), 2-hydroxy-5-methoxyacetophenone (H2L3, complex 3) and 2-hydroxy-5-chloroacetophenone (H2L4, complex 4), have been synthesized and characterized by analytical and spectral methods. These complexes exhibited the potential abilities to suppress the erythrocytes carbonic anhydrase enzymatic activity in type 1 and type 2 diabetic patients (in vitro), promising antidiabetic activity against T2 diabetic mice (in vivo). They also exhibited significant cytotoxic activity against cervical cancer (SiHa) cells (in vitro) as the IC50 value of complexes 1, 2 and 4 is substantially lower than the value found for cisplatin while that of 3 is comparable and follow the order: 4 < 1 < 2 < 3 and can kill the cells by apoptosis via the generation of reactive oxygen species (ROS). The complexes are soluble both in water and octanol media and also non-toxic at working concentrations. The antidiabetic activity of these four complexes follows the order: 4 > 2 > 1 > 3 while both the carbonic anhydrase and cytotoxic activity follow the order: 4 > 1 > 2 > 3 suggesting that complex 4, containing electron withdrawing Cl atom is the most reactive while 3 with electron donating OCH3 group is the least reactive species. The molecular docking study on hCA-I and hCA-II demonstrates that complexes interact via hydrogen bonding as well as different types of π-stacking.

A crystallography-based investigation of weak interactions for drug design against COVID-19.

Interactions between proteins and small molecules play important roles in the inhibition of protein function. However, a lack of proper knowledge about non-covalent interactions can act as a barrier towards gaining a complete understanding of the factors that control these associations. To find effective molecules for COVID-19 inhibition, we have quantitatively investigated 143 X-ray crystal structures of the SARS-CoV-2 Mpro protein of coronavirus with covalently or non-covalently bound small molecules (SMs). Our present study is able to explain ordinary and perceptive aspects relating to protein inhibition. The active site of the protein consists of 21 amino acid residues, but only nine are actively involved in the ligand binding process. The H41, M49, and C145 residues have highest priority with respect to interactions with small molecules through hydrogen bond, CH-π, and van der Waals interactions. At the active site, this ranking of amino acids is clear, based on different spatial orientations of ligands, and consistent with the electronic properties. SMs with aromatic moieties that bind to the active site of the protein play a distinct role in the determination of the following order of interaction frequency with the amino acids: CH-π > H-bonding > polar interactions. This present study revealed that the G143 and C145 residues play crucial roles in the recognition of the carbonyl functionality of SMs through hydrogen bonding. With this knowledge in mind, an effective inhibitor small-molecule for SARS-CoV-2 Mpro was designed: docking studies showed that the designed molecule has strong binding affinity towards the protein. The non-covalent interactions in the protein-ligand complex are in good agreement with the results obtained from X-ray crystallography. Moreover, the present study focused on weak forces and their influence on protein inhibition, henceforth shedding much light on the essential requirements for moieties that should be present in a good inhibitor and their orientations at the ligand binding site.

Molecular designing, crystal structure determination and in silico screening of copper(II) complexes bearing 8-hydroxyquinoline derivatives as anti-COVID-19.

The pandemic by COVID-19 is hampering everything on the earth including physical and mental health, daily life and global economy. At the moment, there are no defined drugs, while few vaccines are available in the market to combat SARS-CoV-2. Several organic molecules were designed and tested against the virus but they did not show promising activity. In this work we designed two copper complexes from the ligands analogues with chloroquine and hydroxychloroquine. Both the ligands and complexes were well characterized by using various spectroscopic, thermal and X-ray diffraction techniques. Both the complexes as well as ligands were screened through in silico method with the chloroquine and hydroxychloroquine which essentially proved pivotal for successful understanding towards the target protein and their mechanism of action. The results indicated that the balanced hydrophobic and polar groups in the complexes favor their binding in the active site of the viral ADP-ribose-1 monophosphatase enzyme over the parent organic molecules.

Anti-COVID-19 terpenoid from marine sources: A docking, admet and molecular dynamics study.

Traditional medicines contain natural products (NPs) as main ingredient which always give new direction and paths to develop new advanced medicines. In the COVID-19 pandemic, NPs can be used or can help to find new compound against it. The SARS coronavirus-2 main protease (SARS CoV-2 Mpro) enzyme, arbitrate viral replication and transcription, is target here. The study show that, from the electronic features and binding affinity of all the NPs with the enzyme, the compounds with higher hydrophobicity and lower flexibility can be more favorable inhibitor. More than fifty NPs were screened for the target and one terpenoid (T3) from marine sponge Cacospongia mycofijiensis shows excellent SARS CoV-2 Mpro inhibitory activity in comparison with known peptide based inhibitors. The molecular dynamics simulation studies of the terpenoids with the protein indicates that the complex is stable and hydrogen bonds are involved during the complexation. Considering binding affinity, bioavailability, pharmacokinetics and toxicity of the compounds, it is proposed that the NP T3 can act as a potential drug candidate against COVID-19 virus.

Self-assembling behaviour of a modified aromatic amino acid in competitive medium.

Aromatic amino acid, specifically phenylalanine (Phe), is one of the most studied building blocks in peptide synthesis due to its importance in biology. It is reported in the literature that Phe-containing peptides have a high tendency to form different self-assembled materials due to efficient aromatic-aromatic interactions. In this article, we have tuned the supramolecular interactions of phenylalanine by making it electron-deficient upon introduction of the nitro group in the ring. The presence of the nitro group has a profound influence on the self-assembly process. It has been observed that 4-nitrophenylalanine (4NP) is a highly efficient gelator compared with the native phenylalanine in DMSO solvent in terms of minimum gelation concentration and it forms hydrogen bonding mediated crystals in water. The change of self-assembling patterns of 4NP in these solvents was studied using X-ray diffraction, UV-Vis spectroscopy, FE-SEM and other techniques. With the help of different experimental data and density functional theory (DFT), we have simulated the theoretical structure of 4NP in DMSO. The theoretical structure of 4NP in DMSO is different compared with that of crystals in water. We then studied the self-assembly process of 4NP in the mixed solvent of DMSO (polar aprotic) and water (polar protic). Different competitive non-covalent interactions of solvents as well as the ratio of the solvent mixture guide the final self-assembly state of 4NP.

Curious Results in the Prospective Binding Interactions of the Food Additive Tartrazine with ß-Lactoglobulin.

The detailed characterizations of the binding interactions between food additive tartrazine (TZ) and ß-lactoglobulin (ß-LG) have been investigated through spectroscopic techniques combined with a molecular modeling study. A series of analyses, such as hyperchromic change in the UV-visible spectra, temperature-dependent quenching constant, time-resolved fluorescence, and Rayleigh scattering measurements, show that quenching of ß-LG proceeds by a static quenching mechanism. TZ specifically binds with ß-LG in a stoichiometry ratio of 1:1, and the observed binding constants (104, K) are 7.64, 9.13, 9.72, and 10.79 at 293, 298, 303, and 308 K, respectively. However, the curious results of binding constants (K) with temperature, encountered in the static quenching, have been well explained on the basis of Le Chatelier's principle. Thermodynamic data and pH-dependent studies along with the surface hydrophobicity binding displacement assay reveal that the durable mode of binding is chiefly entropy-driven, revealing noteworthy interactions of such ionic molecules with the hydrophobic part of ß-LG. The modulation of protein conformation has been investigated through steady-state absorption spectroscopy, synchronous emission spectroscopy, circular dichroism, and dynamic light scattering studies. TZ acts as a potential inhibitor in fibrillogenesis. Furthermore, the molecular docking study offers accurate insights about the binding of TZ with ß-LG, in consistence with the experimental results. This study would be helpful in pharmaceutical, food, and industrial engineering chemistry research.

Antibacterial activities of sulfamethoxazolyl-azo-phenols and their Cu(II) complexes along with molecular docking properties.

Sulfamethoxazolyl-azo-phenols [SMX-N=N-C6H2(R)(R/)-OH] (1a, 2a) and their Cu(II) complexes, [Cu(SMX-N=N-C6H2(R)(R/)-O)2] (1b, 2b) (R = p-OMe, R/ = H, 1a/1b; R = p-Cl, R/ = m-CH3, 2a/2b) show antibacterial sensitivity against Gram-positive bacteria, B. subtillis; IC50: 281.47 ± 1.84 µM (1a), 126.39 ± 1.66 µM (1b), and 279.94 ± 3.15 µM (2a), 123.62 ± 1.27 µM(2b), and Gram-negative bacteria, E. coli; IC50: 204.66 ± 3.31 µM (1a) and 89.05 ± 1.48 µM (1b), 223.13 ± 2.71 µM (2a), and 98.26 ± 1.59 µM (2b). Interaction of DNA with free ligand (1a and 2a) is insignificant, while the complexes (1b and 2b) interact strongly and the binding constants are K b, 8.413 × 104 M-1 (1b) and 6.56 × 105 M-1 (2b). Optimized structures of the compounds are docked with protein structure of DHPS (E. coli) to propose the most favoured binding mode of the drugs in the active site. The in silico test of the compound helps to understand drug metabolism, drug-protein interactions, and toxicity (ADMET).

Comparative study on Antibacterial efficacy of a series of chromone sulfonamide derivatives against drug-resistant and MDR-isolates.

Sulfonamide derivatives have numerous pharmaceutical applications having antiviral, antibacterial, antifungal, antimalarial, anticancer, and antidepressant activities. The structural flexibility of sulfonamide derivatives makes them an excellent candidate for the development of new multi-target agents, although long-time exposure to sulfonamide drugs results in many toxic impacts on human health. However, sulfonamides may be functionalized for developing less toxic and more competent drugs. In this work, sulfonamides including Sulfapyridine (a), Sulfathiazole (b), Sulfamethoxazole (c), and Sulfamerazine (d) are used to synthesize Schiff bases of 7-hydroxy-4-methyl-2-oxo-2H-chromene-8-carbalde-hyde (1a-1d). The synthesized compounds were spectroscopically characterized and tested against hospital isolates of three Gram-positive (Methicillin-resistant Staphylococcus aureus PH217, Ampicillin-resistant Coagulase-negative Staphylococcus aureus, multidrug-resistant (MDR) Enterococcus faecalis PH007R) and two Gram-negative bacteria (multidrug-resistant Escherichia coli, and Salmonella enterica serovar Typhi), compared to the quality control strains from ATCC (S. aureus 29213, E. faecalis 25922, E. coli 29212) and MTCC (S. Typhi 734). Two of the four Schiff bases 1a and 1b are found to be more active than their counterpart 1c and 1d; while 1a have showed significant activity by inhibiting MRSA PH217 and MDR isolates of E. coli at the minimum inhibitory concentration (MIC) of 150 µg/mL and 128 µg/mL with MBC of 1024 µg/mL, respectively. On the other hand, the MIC of 1b was 150 µg/mL against both S. aureus ATCC 29213 and Salmonella Typhi MTCC 734, compared to the control antibiotics Ampicillin and Gentamycin. Scanning electron microscopy demonstrated the altered surface structure of bacterial cells as a possible mechanism of action, supported by the in-silico molecular docking analysis.

Structural, Theoretical Investigations, Hirshfeld Surface Analysis, and Cytotoxicity Profile of a Neocuproine-Co(II)-Based Discrete Homodinuclear Complex.

In this work, we aimed to synthesize a new cobalt(II) complex, namely [Co2(µ-HIPA)(NC)2(H2O)3(NO3)]·(NO3)(C2H5OH)(1) (where H3IPA = 5-hydroxy isophthalic acid and NC = 2,9-dimethyl-1,10-phenanthroline or neocuproine), as a promising chemotherapeutic agent. The diffraction (single crystal-XRD and powder-XRD), spectroscopic (FTIR and UV-visible), molar conductance, and thermal techniques were used to characterize complex 1. Single-crystal X-ray diffraction analysis reveals that Co(II) exists in an octahedral geometry, with the ligation of four oxygen atoms, and two nitrogen atoms. Topological analysis of complex 1 reveals 2,6C6 topological type as an underlying net. The plausible intermolecular interactions within complex 1 that control the crystal packing were analyzed by Hirshfeld surface analysis. In vitro cytotoxicity of complex 1 was evaluated against acute myeloid leukemia (THP-1), colorectal (SW480), and prostate (PC-3) cancer cell lines by utilizing an MTT assay. The result shows that complex 1 can inhibit the growth of cancer cells (THP-1, SW480, and PC-3) at lower inhibitory concentration (IC50) values of > 100, 43.6, and 95.1 µM respectively. The morphological changes induced by complex 1 on THP-1 and SW480 cancer cell lines were carried out with acridine orange/ethidium bromide staining methods. Additionally, comprehensive molecular docking studies were performed to understand the potential binding interactions of complex 1 with different bio-macromolecules.

Anti-HSV nucleoside and non-nucleoside analogues: spectroscopic characterisation of naphthyl and coumarinyl amides and their mode and mechanism of antiviral action.

Nucleoside analogues acyclovir, valaciclovir, and famciclovir are the preferred drugs against human Herpes Simplex Viruses (HSVs). However, the viruses rapidly develop resistance against these analogues which demand safer, more efficient, and nontoxic antiviral agents. We have synthesized two non-nucleoside amide analogues, 2-Oxo-2H-chromene-3-carboxylic acid [2-(pyridin-2-yl methoxy)-phenyl]-amide (HL1) and 2-hydroxy-1-naphthaldehyde-(4-pyridine carboxylic) hydrazone (HL2). The compounds were characterized by different physiochemical methods including elementary analysis, FT-IR, Mass spectra, 1H-NMR; and evaluated for their antiviral efficacy against HSV-1F by Plaque reduction assay. The 50% cytotoxicity (CC50), determined by MTT test, revealed that HL1 (270.4 µg/ml) and HL2 (362.6 µg/ml) are safer, while their antiviral activity (EC50) against HSV-1F was 37.20 µg/ml and 63.4 µg/ml against HL1 and HL2 respectively, compared to the standard antiviral drug Acyclovir (CC50 128.8 ± 3.4; EC50 2.8 ± 0.1). The Selectivity Index (SI) of these two compounds are also promising (4.3 for HL1 and 9.7 for HL2), compared to Acyclovir (49.3). Further study showed that these amide derivatives block the early stage of the HSV-1F life cycle. Additionally, both these amides make the virus inactive, and reduce the number of plaques, when infected Vero cells were exposed to HL1 and HL2 for a short period of time. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03658-0.

Anion-assisted supramolecular polymerization of luminescent organic π-conjugated chromophores in a moderately polar solvent: tunable nanostructures and their corresponding effects on electronic properties.

Supramolecular polymers of π-conjugated organic chromophores have emerged as promising candidates in organic electronics because of their dynamic and highly ordered molecular organization. Herein, we demonstrate the formation of luminescent, highly conducting supramolecular polymers of a functionalized naphthalimide π-chromophore-based organic semiconductor in a moderately polar organic solvent (tetrahydrofuran) by overcoming solute-solvent H-bonding via assistance from fluoride anions. The polymerization is exclusively guided by the synergistic effects of cascade H-bonding (F-⋯H-N- of primary amines, followed by -CO⋯H-N- of amides), π-π stacking and hydrophobic interactions. An increasing molar equivalent of anions leads to a morphology transition from 1D nanowires to 2D nanosheets via nanotubes and nanorings, but above a particular threshold of the same anion, depolymerization-mediated disruption of long-range order and formation of non-luminescent spherical particles was observed. Such significant impacts of anions in supramolecular polymerization-depolymerization were utilized in modulating the electronic properties of this naphthalimide-based organic semiconductor.

Evaluation of F-18 FDG radiopharmaceuticals through Molecular Docking and radiation effects.

Fluorodeoxyglucose (FDG), marked with the most used Positron Emission Tomography (PET) radiopharmaceutical Fluorine-18 (F-18), is a glucose analog and is taken to living cells through membrane glucose carriers. F-18 FDG involvement in tissue is proportional to glucose use. In many cancers, there is increased glucose use due to increased gluten expression and hexokinase activity. F-18 FDG PET is a proven method for diagnosis, staging, re-staging, and evaluation of treatment response in oncology. The purpose of this study is to find the effect of ionizing radiation on proteins in the mechanism of action of FDG and determine to Molecular mechanisms of F-18 FDG accumulation in metabolism. In the study, two different models were used together, the first method, the study was Molecular Docking method for modeling molecules deconstructed and the structure of FDG was energy minimized by utilizing the density functional theory, and the B3LYP functional was used with 6-311G basis set. The second method was the Monte Carlo method for modeling ionizing radiation interactive with the potential routes of FDG metabolism within the cell. It was determined that the Gibbs free energy (ΔG) change was compatible with the ionizing radiation factors for binding of FDG to the aphthous regions of Glucose-6-phosphate isomerase (G1), hexokinase (G2), and glucose transporter-1 (G3) were selected. In this study, the strong binding of FDG to protein influences the effect of radiation on the active site of enzymes. The G1 and G3 shown in the study interacted with only one charged amino acid FDG, and the absence of an aromatic residue around it can be considered among the results of this study as the cause of the low protective effect against ionizing radiation.