Mixed bivalent transition metal complexes of 1,10-phenanthroline and 2-aminomethylthiophenyl-4-bromosalicylaldehyde Schiff base: Spectroscopic, molecular modeling and biological activities

Synthesis, Characterization, and Antioxidant and Bleomycin‐Dependent DNA Damage Evaluation of Curcumin Analogs

“…By comparing the results obtained for the antioxidant activity of the compounds reported in this study with their structures, the following structure SARs were postulated: Compounds 1 , 13 , 15 , 21 , 22 , and 23 have comparatively higher antioxidant activity than ascorbic acid, which may be attributed to the presence of OH, methoxy, pyrazole, oxazole, and indole moieties. Cyclization of the hydrazone derivatives 6 and 7 into the triazine derivatives 11 and 12 , respectively, enhance the biological activity. Compounds 23 > 21 > 22 may be attributed to decrease in the mesomeric effect (M + ) as follows: Cl < H < CH 3 . Compound 1 exhibited good antioxidant activity compared to the new synthesized compounds, which may be due to the presence of two free α,β‐unsaturated ketones. Compounds bearing ortho ‐diphenoxyl and/or ortho ‐methoxyphenoxyl groups exhibit remarkably higher antioxidative activity than the ones bearing no such functionalities, which gives us useful information for antioxidant drug design. The introduction of a heterocyclic ring like pyrazole, trizaine, oxazole, and indole rings enhances the antioxidant activity and gives us useful information for antioxidant drug design. This in agreement with the results reported in literature . …”

Synthesis of some transition metal complexes of novel 1-methylpyrazole-3-aldehyde-4-(2-pyridyl) thiosemicarbazone: Spectroscopic and in vitro biological activity studies

“…In the Co(II) complex, only two bands are observed at 9935 cm -1 4 T1g(F) → 4 T2g(F) (1) and 20,423 cm -1 4 T1g(F) → 4 T1g(P) (3) as reported in many octahedral cobalt(II) complexes [45,46]. The ν2 transition was not observed due to very weak intensity.…”

Synthesis, Antimicrobial Activity and Molecular Modeling of Some Novel 5‐Aminopyrazole, Pyrazolo[1,5‐a]pyrimidine, Bispyrazole and Bispyridone Derivatives Containing Antipyrinyl Moiety

“…The most stable structures for the 21a and 21b as representative compounds of the synthesized compounds subsequently optimized to the closest local minimum at the semiempirical level using PM3 parameterizations. The values of the following parameters: the highest occupied molecular orbital energy (EHOMO), the lowest unoccupied molecular orbital energy (ELUMO), the difference between HOMO and LUMO energy levels (ΔE), Mulliken electronegativity (χ), chemical potential (Pi), global hardness (η), global softness (S), and global electrophilicity (ω) have been calculated using semi‐empirical PM3 method as implemented in HyperChem . In a first step, the molecular geometries of all compounds were fully optimized in the gas phase to gradients of 0.01 kcal.mol −1 Å −1 and afterwards the molecular descriptors were determined.…”