دنيا لفته محمد الدحيدحاوي

Background: Coumarin is quite extend in plants including various vegeta- bles, flavors, foods. Coumarin has various significant medicinal activities such as anti-inflammatory, anti-oxidant, anti-viral, anti-microbial, anti-cancer and has been indicated to increase central nervous system activity. Methods: The syntheses of tailor-made coumarins, which are highly compelling for medical applications due to their structurally interesting antioxidant activity, were report in this manuscript. Coumarins were synthesized success- fully through the modification of 4-hydroxycoumarin by different reaction steps. The molecular structures of the coumarins were characterized by the Fourier transformation infrared and Nuclear magnetic resonance (NMR) spectroscopies. The antioxidant efficiency of the 4-hydroxycoumarins were evaluated by typical spectroscopic method, using radicals DPPH• and H2O2. Results: The new coumarins synthesized in this work exhibited an excellent antioxidant compared to the free vitamin C. Molecular modelling studies using DFT (Density Functional Theory) calculations showed that there is a high correlation between dipole moment, Ionization potential (IP), Electron affinity (EA), Hardness (η), Softness (S), Electro negativity (μ), energy gap, HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular) energies and antioxidant activity. Conclusion: New coumarin derivatives were successfully synthesized using chemical methods. The characterized of these coumarins were done by using different spectroscopic techniques (FT-IR and NMR) and micro-elemental analysis (CHNS). The antioxidant activity of these coumarins were determined by using DPPH and hydrogen peroxide assays. Results indicated that the new coumarins possess higher scavenging activity than vitamin C.

Compounds that can bind and stabilize non-canonical DNA structures are named quadruplex and are of interest in anticancer drug design due to their selective inhibitions of telomerase and consequent effects on cell proliferation. In this study, we report novel Co/Cu [II] complex compounds as G-quadruplex DNA binding ligands. The results from the preliminary assay indicated that the introduction of a positively charged 6-membered tail to the aromatic terminal group of benzimidazole significantly enhanced the binding affinity with the quadruplex and exhibited anti-telomerase activity. These derivatives showed significant selectivities for the telomeric quadruplex over duplex nucleic acids. The stabilization of non-canonical forms estimated with the FRET DNA technology using different sequences, such as F21T, c-kit1 and c-kit2, in cancer cell lines were assessed. Three members of this family showed to be very selective in stabilizing one particular G-quadruplex.

Syntheses of coumarins, which are a structurally interesting antioxidant activity, was done in this article. The modification of 7-hydroxycoumarin by different reaction steps was done to yield target compounds. Molecular structures were characterized by different spectroscopical techniques (Fourier transformation infrared and nuclear magnetic resonance). Antioxidant activities were performed by using various in vitro spectrophometric assays against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydrogen peroxide (H2O2). All compounds exhibited high efficiency as antioxidants compared to ascorbic acid. The highest efficiency scavenging activity was found for compound 3 (91.0 ± 5.0), followed by compounds 2 and 4 (88.0 ± 2.00; and 87.0 ± 3.00). Ascorbic acid C was used as a standard drug with a percentage inhibition of 91.00 ± 1.5. The mechanism of the synthesized compounds as antioxidants was also studied. Hartree–Fock–based quantum chemical studies have been carried out with the basis set to 3-21G, in order to obtain information about the three-dimensional (3D) geometries, electronic structure, molecular modeling, and electronic levels, namely HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital), to understand the antioxidant activity for the synthesized compounds.

Introduction: Coumarin is a natural product compound known for its medicinal properties. Methods: The rational design of 4-hydroxycoumarin functionalized thiadiazoles (3 and 4) was synthesized with tailor-made antioxidant properties. The strategy involves intra-molecular cyclization of 2-(coumarin-4-yloxy) acetic acid under reflux conditions. Antioxidant activity of synthesized compounds were performed using various in vitro assays against 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydrogen peroxide (H2O2) scavenging. Results: The results revealed that tested compounds 3 and 4 are much higher than well-known antioxidant compound naming ascorbic acid. They showed good scavenging capacity against DPPH and hydroxyl radicals. Ab initio HF (Hartree–Fock) with 3-21G basis set for the title compounds demonstrated the correlation of scavenging activities and theoretical parameters (such as, dipole-moment, ionization-potential, electron-affinity and highest occupied molecular orbital). Conclusion: In conclusion Coumarins were successfully synthesized and were evaluated as antioxidants by DPPH and hydrogen peroxide assays and they were indicated that they had good scavenging activities. The synthesized antioxidants were investigated theoretically and also some quantum chemical parameters were calculated.

In this study, we report novel compounds as polyamide compounds with aliphatic tertiary amine tail, compounds synthesized by conventional solution method employing DIC/HOBT as coupling system. The building block molecule was obtained by Chan-lam mediated oxidative coupling reaction in air; the biological activity against a panel of cancer cell line was assessed using SRB method. The results from preliminary assay indicated that introducing of imidazole heterocyclic unit instead of pyrrole in Distamycine significantly enhance the binding affinity with the quadruplex. The stabilization of non-canonical form was estimated with FRET DNA Technology using different sequences such as F21T, c-Myc, c-kit1 and c-kit2. Two member compounds (6 & 7) showed to be very selective in stabilizing one particular G-Quadruplex

Cancer is the effective reasons of death and solely little advance has been completed in diminishing the r of this disease. Cancers might be created in one of the three forms, mostly untrue diet, hereditary predisposition and out of the environment. Cancerogenesis is a method in which healthy cells transform into neoplastic mass, and disrupts cellular functions such as proliferation, differentiation and growth as a result of insufficiency response to the conventional control mechanism in cells, Cell reproduction in normal human tissues is regulated by a collection of proteins that control proliferative and inhibitory stimuli

Recently non-steroidal anti-inflammatory drugs (NSAIDs) have been proposed to prevent or to cure Alzheimer’s disease. In this respect, we synthesized new potential prodrugs of several NSAIDs in order to increase their access to the brain. The carboxylic group of NSAIDs was attached to the 1,4- dihydro-1-methylpyridine-3-carboxylate moiety, which acts as a carrier, via an amino acid bridge, according to the chemical delivery approach developed by Bodor.In this study new analogues were synthesized by insertion D- Threonine moiety using esterification method then linked to nicotinic acid by conventional solution method using DCC as coupling reagent all prodrugs were more lipophilic when compared to their corresponding parent compounds and consequently a better blood brain barrier (BBB) penetration is hypothesised the analogues were purified and monitered by TLC , melting point , and IR spectrophotometer FT.IR 8400 was achieved and CHNS analysis.