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101.
A combined experimental study and density functional theory calculations of fac‐[MnBr (CO)3L] complexes (L = 2‐(2′‐pyridyl)benzimidazole ligand, furnished with either morpholine (Lmorph) or phthalimido (Lphth) side‐chain) were performed using different spectral and analytical tools. The synthesized complexes released carbon monoxide upon the exposure to LED source light at 468 nm. Illumination of fac‐[MnBr (CO)3L] (10 μM) in the myoglobin solution (Mb) produced about 25 μM MbCO. The plateau of the CO release process is attained within 25 min. With the aid of time‐dependent density functional theory calculations, the observed lowest energy absorption transition at ~ 400 nm has a ground‐state composed of d (Mn)/π (pyridyl) and excited‐state of ligand π*‐orbitals forming MLCT/π‐π*. Natural population analyses of fac‐[MnBr (CO)3L] were carried out to get information about the strength of Mn–CO bonds, electronic arrangment and natural charge of manganese ion. 相似文献
102.
Nadia H. Metwally Eman A. Ragab Mona S. Mohamed 《Journal of heterocyclic chemistry》2020,57(4):1698-1713
Some novel N5-sulfonylated 4 were synthesized via sulfonylation of 5-amino-1H-pyrazole derivative 1 with arylsulfonyl chlorides. On the other hand, N1-alkylated pyrazoles 7 and 10 were synthesized through alkylation of compound 1 with each of chloroacetamides and ethylchloroacetate under different conditions. Condensation of compounds 4 and 7 with different aromatic aldehydes furnished the corresponding arylidene derivatives. In spite of, condensation of 10 with aromatic aldehydes afforded the 2-(5-amino-2-aryl-1H-pyrazol-1-yl)acetic acid. The structure of the newly synthesized compounds was elucidated by elemental analyses and spectral data. Also, the suggested mechanisms for their formation were studied. Additionally, some selected new compounds were screened against antimicrobial activity. Compound 7c exhibited a higher activity against Candida albicans (inhibition zone diameter [IZD] = 31.3 ± 0.6 mm) than the standard antibiotic Nystatin (IZD = 21 ± 0.5 mm). Also, compound 7c showed minimum inhibitory concentration = 125 and 250 μg/mL against Klebsiella pneumonia and Staphylococcus aureus, respectively. Molecular docking study also was carried out for compound 7c . 相似文献
103.
Moamen S. Refat Ismail Althagafi Nashwa El-Metwaly Reem Shah Hanadi Katouah Ragab R. Amin Yamany B. Yamany Tariq Altalhi Jehan Y. Al-Humaidi 《应用有机金属化学》2020,34(9):e5766
Series of Co (II), Cu (II), Zn (II) and Sn (II) complexes derived from thiosemicarbazide ligand (HTSC), was synthesized by environmentally favorable method (electrochemical). All isolated complexes, were deliberately characterized by available analytical and spectral tools. The proposed molar ratio was 1:2 (M:L) as the only isolated one, beside the significant contribution for solvent molecules. The octahedral configuration was proposed for all complexes. Conformational analysis was implemented using advanced program to determine the best structural forms for complexes. Moreover, essential parameters were calculated to export important features for studied complexes. Meanwhile, Hirshfeld crystal surface properties, were interested to illustrate strength of packing interaction forces. Furthermore, distinction of site types inside the molecule and their H-donor or H-acceptor ability. Antimicrobial study was conducted against different microorganisms, to assert on the importance of new complexes in therapeutic field. Furthermore and to strengthen the study, the inhibition simulation was performed with respect to all complexes against selected pathogen proteins. Essential interaction data, were exported for each docking process, to classify inhibition efficiency. Co (II) and Cu (II) complexes were the complexes that played well in therapeutic simulation treatments against Bacillus subtilis (1bn8) and Candida albicans kinase (4c0t) proteins. 相似文献
104.
New coordination compounds of some selected metal ions from the first and second transition metals series with a Schiff base were synthesized and characterized. The Schiff base is derived from 4-Aminoantipyrine and 3-(hydroxyimino) butan-2-one. The compounds were characterized by different analysis tools like; elemental analysis, mass spectra, Fourier transform infrared (FTIR) as well as electronic spectra, magnetic measurements, molar conductance and thermal analysis technique. All complexes were formed with 1:1 (metal: ligand) stoichiometry except Mn (II) where 1:2 (Mn: ligand) is formed. Schiff base ligand interacted as a tridentate ligand by using the nitrogen atoms of the imine and the oximato groups and the carbonyl oxygen atom as donor groups with all studied metal ions except copper (II) and manganese (II) where the carbonyl oxygen is not shared in the coordination. These complexes show various physicochemical properties. X-ray powder diffraction shows different crystal systems; Cd (II) complex: hexagonal, Cu (II) complex: orthorhombic; and [Ni (II), Mn (II), Rh (III) & Pd (II)] complexes: monoclinic. All compounds showed potent cytotoxicity against the growth of human liver cancer cell lines. The square planar Pd (II) complex was more active than those of octahedral geometries of all other synthesized complexes. Cd (II) complex has the highest microbial growth inhibition than the rest of the prepared complexes. The docking active sites interactions were evaluated using the selected proteins EGFR tyrosine kinase and protein crystal structure of GlcN-O-P synthase. in vitro antioxidant assay revealed potent free radical scavenging activity of the three synthesized Cu (II), Pd (II) and Rh (III) complexes that exceeded the standard ascorbic acid. Pd (II) complex shows the most significant inhibition denaturation percent. 相似文献
105.
Rakesh K. Sindhu Rishu Verma Twinkle Salgotra Md. Habibur Rahman Muddaser Shah Rokeya Akter Waheed Murad Sidra Mubin Parveen Bibi Safaa Qusti Eida M. Alshammari Gaber El-Saber Batiha Micha Tomczyk Hayder M. Al-kuraishy 《Molecules (Basel, Switzerland)》2021,26(17)
Breast cancer persists as a diffuse source of cancer despite persistent detection and treatment. Flavonoids, a type of polyphenol, appear to be a productive option in the treatment of breast cancer, because of their capacity to regulate the tumor related functions of class of compounds. Plant polyphenols are flavonoids that appear to exhibit properties which are beneficial for breast cancer therapy. Numerous epidemiologic studies have been performed on the dynamic effect of plant polyphenols in the prevention of breast cancer. There are also subclasses of flavonoids that have antioxidant and anticarcinogenic activity. These can regulate the scavenging activity of reactive oxygen species (ROS) which help in cell cycle arrest and suppress the uncontrolled division of cancer cells. Numerous studies have also been performed at the population level, one of which reported a connection between cancer risk and intake of dietary flavonoids. Breast cancer appears to show intertumoral heterogeneity with estrogen receptor positive and negative cells. This review describes breast cancer, its various factors, and the function of flavonoids in the prevention and treatment of breast cancer, namely, how flavonoids and their subtypes are used in treatment. This review proposes that cancer risk can be reduced, and that cancer can be even cured by improving dietary intake. A large number of studies also suggested that the intake of fruit and vegetables is associated with reduced breast cancer and paper also includes the role and the use of nanodelivery of flavonoids in the healing of breast cancer. In addition, the therapeutic potential of orally administered phyto-bioactive compounds (PBCs) is narrowed because of poor stability and oral bioavailability of compounds in the gastrointestinal tract (GIT), and solubility also affects bioavailability. In recent years, creative nanotechnology-based approaches have been advised to enhance the activity of PBCs. Nanotechnology also offers the potential to become aware of disease at earlier stages, such as the detection of hidden or unconcealed metastasis colonies in patients diagnosed with lung, colon, prostate, ovarian, and breast cancer. However, nanoformulation-related effects and safety must not be overlooked. This review gives a brief discussion of nanoformulations and the effect of nanotechnology on herbal drugs. 相似文献
106.
Kakos SH Dressel LT Bushendorf JD Kotarba CP Wijetunge P Kulatilleke CP McGillivary MP Chaka G Heeg MJ Ochrymowycz LA Rorabacher DB 《Inorganic chemistry》2006,45(2):923-934
The two ethylene bridges in the macrocyclic tetrathiaether 1,4,8,11-tetrathiacyclotetradecane ([14]aneS(4)) have been systematically replaced by cis- or trans-1,2-cyclopentane to generate a series of new ligands that exhibit differing preferences for the orientation of the sulfur donor atoms while maintaining constant inductive effects. The resulting five dicyclopentanediyl derivatives, along with two previously synthesized monocyclopentanediyl analogues, have been complexed with Cu(II), and their stability constants, formation and dissociation rate constants, and redox potentials have been determined in 80% methanol/20% water (by weight). The crystal structures of the Cu(II) complexes with the five dicyclopentanediyl-[14]aneS(4) diastereomers as well as the structures for a representative Cu(I) complex and one of the free ligands have also been determined. The properties of these complexes are compared to previous data obtained for the corresponding cyclohexanediyl derivatives in an attempt to shed additional light on the influence of sterically constraining substituents upon the properties of macrocyclic ligand complexes. 相似文献
107.
108.
F. M. Ragab 《Mathematische Zeitschrift》1962,78(1):222-230
Ohne Zusammenfassung 相似文献
109.
Theodor W. Güntert Horst H. A. Linde Mohamed S. Ragab Sigrid Spengel 《Helvetica chimica acta》1976,59(6):2138-2148
Synthesis of a homologous steroidal 17β-pyrrolinone. We describe the synthesis of 4′-[(3β-Hydroxy-androst-5-en-17β-yl)methyl]-3′-pyrrolin-2′-one ( 15 ) starting from 3β-acetoxy-23-diazo-21,24-dinorchol-6-en-22-one ( 1 ). 相似文献
110.