Displaying publications 81 - 100 of 800 in total

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  1. Abdullah MA, Mohd Faudzi SM, Nasir NM
    Mini Rev Med Chem, 2021;21(9):1058-1070.
    PMID: 33272171 DOI: 10.2174/1389557520999201203213957
    Medicinal chemists have continuously shown interest in new curcuminoid derivatives, diarylpentadienones, owing to their enhanced stability feature and easy preparation using a one-pot synthesis. Thus far, methods such as Claisen-Schmidt condensation and Julia- Kocienski olefination have been utilised for the synthesis of these compounds. Diarylpentadienones possess a high potential as a chemical source for designing and developing new and effective drugs for the treatment of diseases, including inflammation, cancer, and malaria. In brief, this review article focuses on the broad pharmacological applications and the summary of the structure-activity relationship of molecules, which can be employed to further explore the structure of diarylpentadienone. The current methodological developments towards the synthesis of diarylpentadienones are also discussed.
    Matched MeSH terms: Molecular Structure
  2. Abdelgawad MA, Musa A, Almalki AH, Alzarea SI, Mostafa EM, Hegazy MM, et al.
    Drug Des Devel Ther, 2021;15:2325-2337.
    PMID: 34103896 DOI: 10.2147/DDDT.S310820
    Introduction: Epidermal growth factor receptor (EGFR) inhibition is an imperative therapeutic approach targeting various types of cancer including colorectal, lung, breast, and pancreatic cancer types. Moreover, cyclooxygenase-2 (COX-2) is frequently overexpressed in different types of cancers and has a role in the promotion of malignancy, apoptosis inhibition, and metastasis of tumor cells. Combination therapy has been emerged to improve the therapeutic benefit against cancer and curb intrinsic and acquired resistance.

    Methods: Three semi-synthetic series of compounds (C1-4, P1-4, and G1-4) were prepared and evaluated biologically as potential dual epidermal growth factor receptor (EGFR) and COX-2 inhibitors. The main phenolic constituents of Amaranthus spinosus L. (p-coumaric, caffeic and gallic) acids have been isolated and subsequently subjected to diazo coupling with various amines to get novel three chemical scaffolds with potential anticancer activities.

    Results: Compounds C4 and G4 showed superior inhibitory activity against EGFR (IC50: 0.9 and 0.5 µM, respectively) and displayed good COX-2 inhibition (IC50: 4.35 and 2.47 µM, respectively). Moreover, the final compounds were further evaluated for their cytotoxic activity against human colon cancer (HT-29), pancreatic cancer (PaCa-2), human malignant melanoma (A375), lung cancer (H-460), and pancreatic ductal cancer (Panc-1) cell lines. Interestingly, compounds C4 and G4 exhibited the highest cytotoxic activity with average IC50 values of 1.5 µM and 2.8 µM against H-460 and Panc-1, respectively. The virtual docking study was conducted to gain proper understandings of the plausible-binding modes of target compounds within EGFR and COX-2 binding sites.

    Discussion: The NMR of prepared compounds showed characteristic peaks that confirmed the structure of the target compounds. The synthesized benzoxazolyl scaffold containing compounds showed inhibitory activities for both COXs and EGFR which are consistent with the virtual docking study.

    Matched MeSH terms: Molecular Structure
  3. Zainuri DA, Abdullah M, Zaini MF, Bakhtiar H, Arshad S, Abdul Razak I
    PLoS One, 2021;16(9):e0257808.
    PMID: 34582495 DOI: 10.1371/journal.pone.0257808
    The Ultraviolet-visible (UV-Vis) spectra indicate that anthracenyl chalcones (ACs) have high maximum wavelengths and good transparency windows for optical applications and are suitable for optoelectronic applications owing to their HOMO-LUMO energy gaps (2.93 and 2.76 eV). Different donor substituents on the AC affect their dipole moments and nonlinear optical (NLO) responses. The positive, negative, and neutral electrostatic potential regions of the molecules were identified using molecular electrostatic potential (MEP). The stability of the molecule on account of hyperconjugative interactions and accompanying charge delocalization was analyzed using natural bond orbital (NBO) analysis. Open and closed aperture Z-scans were performed using a continuous-wave frequency-doubled diode-pumped solid-state (DPSS) laser to measure the nonlinear absorption and nonlinear refractive index coefficients, respectively. The valley-to-peak profile of AC indicated a negative nonlinear refractive index coefficient. The obtained single crystals possess reverse saturation absorption due to excited-state absorption. The structural and nonlinear optical properties of the molecules have been discussed, along with the role of anthracene substitution for enhancing the nonlinear optical properties. The calculated third-order susceptibility value was 1.10 x10-4 esu at an intensity of 4.1 kW/cm2, higher than the reported values for related chalcone derivatives. The NLO response for both ACs offers excellent potential in optical switching and limiting applications.
    Matched MeSH terms: Molecular Structure
  4. Khairul WM, Hashim F, Mohammed M, Shah NSMN, Johari SATT, Rahamathullah R, et al.
    Anticancer Agents Med Chem, 2021;21(13):1738-1750.
    PMID: 33176667 DOI: 10.2174/1871520620999201110190709
    INTRODUCTION: In this contribution, a series of alkoxy substituted chalcones were successfully designed, synthesized, spectroscopically characterized and evaluated for their cytotoxicity potential in inhibiting the growth of MCF-7 cells.

    OBJECTIVE: In order to investigate the influence between electron density in conjugated π-systems and biological activities, different withdrawing substituents, namely Nitro (NO2), Cyano (C≡N) and trifluoromethyl (CF3) were introduced in the chalcone-based molecular system.

    METHODS: All the derivatives were then tested on MCF-7 cell line using the fluorescence microscopy-based cytotoxicity analyses.

    RESULTS: The preliminary findings showed that both -NO2 and -CF3 substituents revealed their potential to inhibit the growth of MCF-7 with IC;50 values of 14.75 and 13.75 μg/ml, respectively. In addition, the morphological changes of MCF-7 cells were observed in response to alkoxy substituted chalcone treatment through an induction of apoptosis pathway with cell blebbing, phosphatidylserine exposure and autophagic activity with acidification of lysosomal structure. Intermolecular interaction based on in silico investigation on nitro, trifluoromethyl and cyano based chalcones exhibited several types of interactions with tumor necrosis factor receptor (PDB: 1EXT) protein and high hydrogen bond in the molecule-receptor interaction have given significant impact towards their toxicity on MCF-7 cells.

    CONCLUSION: Significantly, these types of chalcones exhibited ideal and high potential to be further developed as anti-cancer agents.

    Matched MeSH terms: Molecular Structure
  5. Nipun TS, Khatib A, Ibrahim Z, Ahmed QU, Redzwan IE, Saiman MZ, et al.
    Molecules, 2020 Dec 12;25(24).
    PMID: 33322801 DOI: 10.3390/molecules25245885
    Psychotria malayana Jack has traditionally been used to treat diabetes. Despite its potential, the scientific proof in relation to this plant is still lacking. Thus, the present study aimed to investigate the α-glucosidase inhibitors in P.malayana leaf extracts using a metabolomics approach and to elucidate the ligand-protein interactions through in silico techniques. The plant leaves were extracted with methanol and water at five various ratios (100, 75, 50, 25 and 0% v/v; water-methanol). Each extract was tested for α-glucosidase inhibition, followed by analysis using liquid chromatography tandem to mass spectrometry. The data were further subjected to multivariate data analysis by means of an orthogonal partial least square in order to correlate the chemical profile and the bioactivity. The loading plots revealed that the m/z signals correspond to the activity of α-glucosidase inhibitors, which led to the identification of three putative bioactive compounds, namely 5'-hydroxymethyl-1'-(1, 2, 3, 9-tetrahydro-pyrrolo (2, 1-b) quinazolin-1-yl)-heptan-1'-one (1), α-terpinyl-β-glucoside (2), and machaeridiol-A (3). Molecular docking of the identified inhibitors was performed using Auto Dock Vina software against the crystal structure of Saccharomyces cerevisiae isomaltase (Protein Data Bank code: 3A4A). Four hydrogen bonds were detected in the docked complex, involving several residues, namely ASP352, ARG213, ARG442, GLU277, GLN279, HIE280, and GLU411. Compound 1, 2, and 3 showed binding affinity values of -8.3, -7.6, and -10.0 kcal/mol, respectively, which indicate the good binding ability of the compounds towards the enzyme when compared to that of quercetin, a known α-glucosidase inhibitor. The three identified compounds that showed potential binding affinity towards the enzymatic protein in molecular docking interactions could be the bioactive compounds associated with the traditional use of this plant.
    Matched MeSH terms: Molecular Structure
  6. Sabri MZ, Hamid AAA, Hitam SMS, Rahim MZA
    Biophys Chem, 2020 12;267:106492.
    PMID: 33035750 DOI: 10.1016/j.bpc.2020.106492
    Aptamers are oligonucleotides and peptides around 15-100 bases in length and are suitable as detection probes or as therapeutics molecules. There are growing interests in the aptamer screening approach through computational simulation methods. DNA and RNA modelling lacks of validation on their predicted 3D structures due to less number of validation tools, unlike protein structures. We suggest an approach to design the stem-loop/hairpin for the three dimensional structure of DNA aptamers through serial applications of computational prediction methods by comparing the simulated structures with the experimental data deposited in PDB Data bank, followed by MD simulations. The result shows minimal structural differences were observed between the designed and the original NMR aptamers, and the stem-loop conformational structures were also retained during the MD thus suggesting the proposed aptamers designing methods are able to synthesize a high quality molecular structure of hairpin aptamers, comparable to the NMR structures.
    Matched MeSH terms: Molecular Structure
  7. Huong DTM, Chai WS, Show PL, Lin YL, Chiu CY, Tsai SL, et al.
    Int J Biol Macromol, 2020 Dec 01;164:3873-3884.
    PMID: 32896561 DOI: 10.1016/j.ijbiomac.2020.09.020
    Water pollution caused by dyes has been a serious problem affecting human health and environment. The surface of polyacrylonitrile (PAN) nanofiber membranes was modified by mild hydrolysis and coupled with bovine serum albumin (BSA) obtained from the laboratory wastes, resulting in the synthesis of P-COOH and P-COOH-BSA nanofibers. The nanofibers with specific functional groups may enhance their potential applications toward the removal of ionic dyes in wastewater. Toluidine blue O (TBO) was applied as an example of cationic dye to evaluate the removal efficiency of P-COOH-BSA nanofiber. Results showed that the equilibrium dissociation constant and maximum removal capacity were 0.48 mg/mL and 434.78 mg/g, respectively, at pH 12, where the TBO removal can be explained based on Langmuir isotherm and pseudo-second-order model. Desorption studies have shown that TBO adsorbed on P-COOH-BSA protein membrane can be completely eluted with either 1 M NaCl or 50% glycerol. The results of repeated studies indicated that after five consecutive adsorption/desorption cycles, the removal efficiency of TBO can be maintained at ~97%. P-COOH-BSA has shown to be promising adsorbent in TBO dye removal from dye wastewater.
    Matched MeSH terms: Molecular Structure
  8. Khaw KY, Chong CW, Murugaiyah V
    J Enzyme Inhib Med Chem, 2020 Dec;35(1):1433-1441.
    PMID: 32608273 DOI: 10.1080/14756366.2020.1786819
    Mangosteen is one of the best tasting tropical fruit widely cultivated in Southeast Asia. This study aimed to quantify xanthone content in different parts of Garcinia mangostana by LC-QTOF-MS and determine its influence on their cholinesterase inhibitory activities. The total xanthone content in G. mangostana was in the following order: pericarp > calyx > bark > stalk > stem > leaves > aril. The total xanthone content of pericarp was 100 times higher than the aril. Methanol extracts of the pericarp and calyx demonstrated the most potent inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with IC50 values of 0.90 and 0.37 µg/mL, respectively. Statistical analysis showed a strong correlation between xanthone content and cholinesterase inhibition. Nonmetric multidimensional scaling analysis revealed α-mangostin and γ-mangostin of pericarp as the key metabolites contributing to cholinesterase inhibition. Due to the increasing demand of mangosteen products, repurposing of fruit waste (pericarp) has great potential for enhancement of the cognitive health of human beings.
    Matched MeSH terms: Molecular Structure
  9. Pustenko A, Nocentini A, Balašova A, Alafeefy A, Krasavin M, Žalubovskis R, et al.
    J Enzyme Inhib Med Chem, 2020 Dec;35(1):245-254.
    PMID: 31790605 DOI: 10.1080/14756366.2019.1695795
    A new series of homosulfocoumarins (3H-1,2-benzoxathiepine 2,2-dioxides) possessing various substitution patterns and moieties in the 7, 8 or 9 position of the heterocylic ring were prepared by original procedures and investigated for the inhibition of four physiologically relevant carbonic anhydrase (CA, EC 4.2.1.1) isoforms, the human (h) hCA I, II, IX and XII. The 8-substituted homosulfocoumarins were the most effective hCA IX/XII inhibitors followed by the 7-substituted derivatives, whereas the substitution pattern in position 9 led to less effective binders for the transmembrane, tumour-associated isoforms IX/XII. The cytosolic isoforms hCA I and II were not inhibited by these compounds, similar to the sulfocoumarins/coumarins investigated earlier. As hCA IX and XII are validated anti-tumour targets, with one sulphonamide (SLC-0111) in Phase Ib/II clinical trials, finding derivatives with better selectivity for inhibiting the tumour-associated isoforms over the cytosolic ones, as the homosulfocoumarins reported here, is of crucial importance.
    Matched MeSH terms: Molecular Structure
  10. Mohammed A, Velu AB, Al-Hakami AM, Meenakshisundaram B, Esther P, Abdelwahid SA, et al.
    Trop Biomed, 2020 Dec 01;37(4):1062-1073.
    PMID: 33612758 DOI: 10.47665/tb.37.4.1062
    Pandemic H1N1 influenza virus respiratory illness has become an inevitable global health concern. With antigenic drift, it becomes necessary to have drugs over tailor-made HIN1 vaccine every year. In the current study, we screened many Piperine derivative in which, N-5-(3,4-dimethoxyphenyl)-2E,4E-pentadienylpiperidine (AB05) and was further studied for anti-H1N1influenza virus activity and compared with other stains in-vitro on MDCK cell line. Initial cytotoxic doses of AB05 for the MDCK cell line were > 25µM. The results showed a dose-dependent reduction of the viral plaque's in the adsorption assay with EC50 of 0.33 µM. The mechanism of AB05 was by inhibition of matured viral release as evaluated by the time of virus addition with incubation of 6-10 hours. With the promising H1N1 virucidal activity of AB05, we included various strains of human influenza virus to screen AB05 inhibition of Neuraminidase (NA). The result showed 70% NA inhibition in WSN (H1N1), 90% in H3N2 and Influenza B and 49% in Tamiflu resistant H1N1). Further our In silco docking studies substantiated experimental results by showing the difference in binding and cooperation between H1N1 and N3N2. Together these observations illustrate that Piperine derivative AB05 is a promising lead molecule which needs further evaluation in animal models.
    Matched MeSH terms: Molecular Structure
  11. Mirza MU, Ahmad S, Abdullah I, Froeyen M
    Comput Biol Chem, 2020 Dec;89:107376.
    PMID: 32979815 DOI: 10.1016/j.compbiolchem.2020.107376
    Human ubiquitin carboxyl-terminal hydrolase-2 (USP2) inhibitors, such as thiopurine analogs, have been reported to inhibit SARS-CoV papain-like proteases (PLpro). The PLpro have significant functional implications in the innate immune response during SARS-CoV-2 infection and considered an important antiviral target. Both proteases share strikingly similar USP fold with right-handed thumb-palm-fingers structural scaffold and conserved catalytic triad Cys-His-Asp/Asn. In this urgency situation of COVID-19 outbreak, there is a lack of in-vitro facilities readily available to test SARS-CoV-2 inhibitors in whole-cell assays. Therefore, we adopted an alternate route to identify potential USP2 inhibitor through integrated in-silico efforts. After an extensive virtual screening protocol, the best compounds were selected and tested. The compound Z93 showed significant IC50 value against Jurkat (9.67 μM) and MOTL-4 cells (11.8 μM). The binding mode of Z93 was extensively analyzed through molecular docking, followed by MD simulations, and molecular interactions were compared with SARS-CoV-2. The relative binding poses of Z93 fitted well in the binding site of both proteases and showed consensus π-π stacking and H-bond interactions with histidine and aspartate/asparagine residues of the catalytic triad. These results led us to speculate that compound Z93 might be the first potential chemical lead against SARS-CoV-2 PLpro, which warrants in-vitro evaluations.
    Matched MeSH terms: Molecular Structure
  12. Ibeji CU, Salleh NAM, Sum JS, Ch'ng ACW, Lim TS, Choong YS
    Sci Rep, 2020 11 03;10(1):18925.
    PMID: 33144641 DOI: 10.1038/s41598-020-75799-8
    Pulmonary tuberculosis, caused by Mycobacterium tuberculosis, is one of the most persistent diseases leading to death in humans. As one of the key targets during the latent/dormant stage of M. tuberculosis, isocitrate lyase (ICL) has been a subject of interest for new tuberculosis therapeutics. In this work, the cleavage of the isocitrate by M. tuberculosis ICL was studied using quantum mechanics/molecular mechanics method at M06-2X/6-31+G(d,p): AMBER level of theory. The electronic embedding approach was applied to provide a better depiction of electrostatic interactions between MM and QM regions. Two possible pathways (pathway I that involves Asp108 and pathway II that involves Glu182) that could lead to the metabolism of isocitrate was studied in this study. The results suggested that the core residues involved in isocitrate catalytic cleavage mechanism are Asp108, Cys191 and Arg228. A water molecule bonded to Mg2+ acts as the catalytic base for the deprotonation of isocitrate C(2)-OH group, while Cys191 acts as the catalytic acid. Our observation suggests that the shuttle proton from isocitrate hydroxyl group C(2) atom is favourably transferred to Asp108 instead of Glu182 with a lower activation energy of 6.2 kcal/mol. Natural bond analysis also demonstrated that pathway I involving the transfer of proton to Asp108 has a higher intermolecular interaction and charge transfer that were associated with higher stabilization energy. The QM/MM transition state stepwise catalytic mechanism of ICL agrees with the in vitro enzymatic assay whereby Asp108Ala and Cys191Ser ICL mutants lost their isocitrate cleavage activities.
    Matched MeSH terms: Molecular Structure
  13. Abdullah MA, Lee YR, Mastuki SN, Leong SW, Wan Ibrahim WN, Mohammad Latif MA, et al.
    Bioorg Chem, 2020 11;104:104277.
    PMID: 32971414 DOI: 10.1016/j.bioorg.2020.104277
    A series of aminated- (1-9) and sulfonamide-containing diarylpentadienones (10-18) were synthesized, structurally characterized, and evaluated for their in vitro anti-diabetic potential on α-glucosidase and DPP-4 enzymes. It was found that all the new molecules were non-associated PAINS compounds. The sulfonamide-containing series (compounds 10-18) selectively inhibited α-glucosidase over DPP-4, in which compound 18 demonstrated the highest activity with an IC50 value of 5.69 ± 0.5 µM through a competitive inhibition mechanism. Structure-activity relationship (SAR) studies concluded that the introduction of the trifluoromethylbenzene sulfonamide moiety was essential for the suppression of α-glucosidase. The most active compound 18, was then further tested for in vivo toxicities using the zebrafish animal model, with no toxic effects detected in the normal embryonic development, blood vessel formation, and apoptosis of zebrafish. Docking simulation studies were also carried out to better understand the binding interactions of compound 18 towards the homology modeled α -glucosidase and the human lysosomal α -glucosidase enzymes. The overall results suggest that the new sulfonamide-containing diarylpentadienones, compound 18, could be a promising candidate in the search for a new α-glucosidase inhibitor, and can serve as a basis for further studies involving hit-to-lead optimization, in vivo efficacy and safety assessment in an animal model and mechanism of action for the treatment of T2DM patients.
    Matched MeSH terms: Molecular Structure
  14. Konidala SK, Kotra V, Danduga RCSR, Kola PK
    Bioorg Chem, 2020 11;104:104207.
    PMID: 32947135 DOI: 10.1016/j.bioorg.2020.104207
    Four series of thirteen new coumarin-chalcone hybrids (DPCU 1-13, DPCT 1-13, DCCU 1-13 and DCCT 1-13) were designed and synthesized using Biginelli synthesis, Pechmann condensation, Acetylation, and Claisen-Schmidt reactions. Synthesized compounds were tested for insulin receptor in silico docking studies (PDB ID: 1IR3); DCCU 13 and DCCT 13 derivatives received the lowest docking score; Streptozocin (STZ) and Nicotinamide (NA) induced type II diabetes was tested for their anti-diabetic activity in rats. In vivo tests suggested that fasting blood glucose levels of animals treated with DCCU 13 (30 mg/kg body weight) and DCCT 13 (30 mg/kg body weight) were significantly and moderately suppressed, respectively, relative to fasting blood glucose levels of diabetic control animals. Similarly, therapy with DCCU 13 and DCCT 13 attenuated oxidative stress parameters such as lipid peroxidation (MDA), superoxide dismutase (SOD) and increased the glutathione (GSH) in the liver and pancreas in a dose-dependent manner. In comparison, therapy with DCCU 13 (30 mg/kg body weight) mitigated alterations in the histological architecture of the liver and pancreatic tissue. These results indicated that the hybrids DUUC 13 and DCCT 13 at 30 mg/kg had an anti-hyperglycemic and antioxidant impact on STZ + NA mediated type II diabetes in rats. Further detailed work could be required to determine the precise mode of action of the anti-diabetic behavior of hybrids.
    Matched MeSH terms: Molecular Structure
  15. Chan SY, Loh YC, Oo CW, Yam MF
    Bioorg Chem, 2020 11;104:104239.
    PMID: 33142420 DOI: 10.1016/j.bioorg.2020.104239
    The development of vasorelaxant as the antihypertensive drug is important as it produces a rapid and direct relaxation effect on the blood vessel muscles. Resveratrol (RV), as the most widely studied stilbenoid and the lead compound, inducing the excellent vasorelaxation effect through the multiple signalling pathways. In this study, the in vitro vascular response of the synthesized trans-stilbenoid derivatives, SB 1-8e were primarily evaluated by employing the phenylephrine (PE)-precontracted endothelium-intact isolated aortic rings. Herein we report trans-3,4,4'-trihydroxystilbene (SB 8b) exhibited surprisingly more than 2-fold improvement to the maximal relaxation (Rmax) of RV. This article also highlights the characterization of the aromatic protons in terms of their unique splitting patterns in 1H NMR.
    Matched MeSH terms: Molecular Structure
  16. Khaw KY, Kumar P, Yusof SR, Ramanathan S, Murugaiyah V
    Arch Pharm (Weinheim), 2020 Nov;353(11):e2000156.
    PMID: 32716578 DOI: 10.1002/ardp.202000156
    α-Mangostin has been reported to possess a broad range of pharmacological effects including potent cholinesterase inhibition, but the development of α-mangostin as a potential lead compound is impeded by its toxicity. The present study investigated the impact of simple structural modification of α-mangostin on its cholinesterase inhibitory activities and toxicity toward neuroblastoma and liver cancer cells. The dialkylated derivatives retained good acetylcholinesterase (AChE) inhibitory activities with IC50 values between 4.15 and 6.73 µM, but not butyrylcholinesterase (BChE) inhibitory activities, compared with α-mangostin, a dual inhibitor (IC50 : AChE, 2.48 µM; BChE, 5.87 µM). Dialkylation of α-mangostin produced AChE selective inhibitors that formed hydrophobic interactions at the active site of AChE. Interestingly, all four dialkylated derivatives of α-mangostin showed much lower cytotoxicity, being 6.4- to 9.0-fold and 3.8- to 5.5-fold less toxic than their parent compound on neuroblastoma and liver cancer cells, respectively. Likewise, their selectivity index was higher by 1.9- to 4.4-fold; in particular, A2 and A4 showed improved selectivity index compared with α-mangostin. Taken together, modification of the hydroxyl groups of α-mangostin at positions C-3 and C-6 greatly influenced its BChE inhibitory and cytotoxic but not its AChE inhibitory activities. These dialkylated derivatives are viable candidates for further structural modification and refinement, worthy in the search of new AChE inhibitors with higher safety margins.
    Matched MeSH terms: Molecular Structure
  17. Low FW, Chin Hock G, Kashif M, Samsudin NA, Chau CF, Indah Utami AR, et al.
    Molecules, 2020 Oct 21;25(20).
    PMID: 33096759 DOI: 10.3390/molecules25204852
    Renewable solar energy is the key target to reduce fossil fuel consumption, minimize global warming issues, and indirectly minimizes erratic weather patterns. Herein, the authors synthesized an ultrathin reduced graphene oxide (rGO) nanosheet with ~47 nm via an improved Hummer's method. The TiO2 was deposited by RF sputtering onto an rGO nanosheet with a variation of temperature to enhance the photogenerated electron or charge carrier mobility transport for the photoanode component. The morphology, topologies, element composition, crystallinity as well as dye-sensitized solar cells' (DSSCs) performance were determined accordingly. Based on the results, FTIR spectra revealed presence of Ti-O-C bonds in every rGO-TiO2 nanocomposite samples at 800 cm-1. Besides, XRD revealed that a broad peak of anatase TiO2 was detected at ~25.4° after incorporation with the rGO. Furthermore, it was discovered that sputtering temperature of 120 °C created a desired power conversion energy (PCE) of 7.27% based on the J-V plot. Further increase of the sputtering temperature to 160 °C and 200 °C led to excessive TiO2 growth on the rGO nanosheet, thus resulting in undesirable charge recombination formed at the photoanode in the DSSC device.
    Matched MeSH terms: Molecular Structure
  18. Adalat B, Rahim F, Taha M, Alshamrani FJ, Anouar EH, Uddin N, et al.
    Molecules, 2020 Oct 20;25(20).
    PMID: 33092223 DOI: 10.3390/molecules25204828
    We synthesized 10 analogs of benzimidazole-based thiosemicarbazide 1 (a-j) and 13 benzimidazole-based Schiff bases 2 (a-m), and characterized by various spectroscopic techniques and evaluated in vitro for acetylcholinesterase (AchE) and butyrylcholinesterase (BchE) inhibition activities. All the synthesized analogs showed varying degrees of acetylcholinesterase and butyrylcholinesterase inhibitory potentials in comparison to the standard drug (IC50 = 0.016 and 4.5 µM. Amongst these analogs 1 (a-j), compounds 1b, 1c, and 1g having IC50 values 1.30, 0.60, and 2.40 µM, respectively, showed good acetylcholinesterase inhibition when compared with the standard. These compounds also showed moderate butyrylcholinesterase inhibition having IC50 values of 2.40, 1.50, and 2.40 µM, respectively. The rest of the compounds of this series also showed moderate to weak inhibition. While amongst the second series of analogs 2 (a-m), compounds 2c, 2e, and 2h having IC50 values of 1.50, 0.60, and 0.90 µM, respectively, showed moderate acetylcholinesterase inhibition when compared to donepezil. Structure Aactivity Relation of both synthesized series has been carried out. The binding interactions between the synthesized analogs and the enzymes were identified through molecular docking simulations.
    Matched MeSH terms: Molecular Structure
  19. Abdul Rahman SF, Xiang Lian BS, Mohana-Kumaran N
    Future Oncol, 2020 Oct;16(28):2235-2249.
    PMID: 32715755 DOI: 10.2217/fon-2020-0389
    The B-cell lymphoma 2 (BCL-2) anti-apoptotic proteins have become attractive therapeutic targets especially with the development of BH3-mimetics which selectively target these proteins. However, it is important to note that expression levels of the anti-apoptotic proteins and their relevance in inhibiting apoptosis varies between different cell lineages. This addiction to certain anti-apoptotic proteins for survival, can be determined with various techniques and targeted effectively with selective BH3-mimetics. Studies have highlighted that anti-apoptotic proteins BCL-XL and MCL-1 are crucial for cervical cancer cell survival. Co-targeting BCL-XL and MCL-1 with selective BH3-mimetics yielded promising results in cervical cancer cell lines. In this review, we focus on the expression levels of the anti-apoptotic proteins in cervical cancer tissues and how to possibly target them with BH3-mimetics.
    Matched MeSH terms: Molecular Structure
  20. Mohammed AAM, Suaifan GARY, Shehadeh MB, Okechukwu PN
    Eur J Med Chem, 2020 Sep 15;202:112513.
    PMID: 32623216 DOI: 10.1016/j.ejmech.2020.112513
    Herein we report the design, synthesis and biological evaluation of structurally modified ciprofloxacin, norfloxacin and moxifloxacin standard drugs, featuring amide functional groups at C-3 of the fluoroquinolone scaffold. In vitro antimicrobial testing against various Gram-positive bacteria, Gram-negative bacteria and fungi revealed potential antibacterial and antifungal activity. Hybrid compounds 9 (MIC 0.2668 ± 0.0001 mM), 10 (MIC 0.1358 ± 00025 mM) and 13 (MIC 0.0898 ± 0.0014 mM) had potential antimicrobial activity against a fluoroquinolone-resistant Escherichia coli clinical isolate, compared to ciprofloxacin (MIC 0.5098 ± 0.0024 mM) and norfloxacin (MIC 0.2937 ± 0.0021 mM) standard drugs. Interestingly, compound 10 also exerted potential antifungal activity against Candida albicans (MIC 0.0056 ± 0.0014 mM) and Penicillium chrysogenum (MIC 0.0453 ± 0.0156 mM). Novel derivatives and standard fluoroquinolone drugs exhibited near-identical cytotoxicity levels against L6 muscle cell-line, when measured using the MTT assay.
    Matched MeSH terms: Molecular Structure
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