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41.
A number of new derivatives of pyrimido[4,5‐c]pyridazine have been synthesized from the treatment of 6‐acetyl‐3‐amino‐2,5‐diphenyl‐2,5‐dihydropyridazine‐4‐carbonitrile ( 1 ) as precursor with various reactants obtained quantitatively the desired products ( 2 ), ( 5 ), ( 7 ), and ( 9a , 9b , 9c , 9d , 9e ). The structures of all the synthesized products have been elucidated thoroughly. The potential AKT1 inhibitory activities of these new synthesized compounds have also been studied by docking calculations, which have been performed in Gold 5.2 software using Genetic algorithm.  相似文献   
42.
Several new derivatives of oxazolo[5,4‐d]pyrimidine ( 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h ) have been synthesized through the reaction of 2,4‐dichloro‐6‐methyl‐5‐nitropyrimidine ( 2 ) with aryl carboxylic acids in refluxing POCl3. Further treatment of compounds ( 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h ) with hydrazine hydrate gave the hydrazine derivatives ( 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h ) that were subsequently cyclized into a novel heterocyclic system, oxazolo[5,4‐d][1,2,4]triazolo[4,3‐a]pyrimidine ( 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j , 5k , 5l , 5m , 5n , 5o , 5p ) and ( 7a , 7b , 7c , 7d ) on treatment with triethylorthoesters or carbondisulfide and alkylhalides, respectively.  相似文献   
43.
In this study, the interaction between (2,2?-bipyridine)(pyrrolidinedithiocarbamato) platinum(II) nitrate, [Pt(bpy)(pyr-dtc]NO3, and human serum albumin (HSA) was investigated by various spectroscopic methods (UV–vis, fluorescence, CD and FT-IR) and molecular docking technique at three temperatures. UV–vis absorption spectroscopy showed that Pt(II) complex can denature the protein at moderate concentrations. The results of emission quenching at two temperatures has revealed that the quenching mechanism of Pt(II) complex with HSA was static quenching mechanism. Binding constants (K), binding site number (n) and corresponding thermodynamic parameters ?G?, ?H? and ?S? were calculated and revealed that hydrophobic forces played a major role when Pt(II) complex interacted with HSA. The binding distance (r) between above complex and HSA based on Förster?s theory of non-radiation energy transfer was calculated as 3.22 nm. Alterations of HSA secondary structure induced by complex were confirmed by FT-IR and CD measurements. Also, a molecular docking study was performed for identification of key structural features of binding of the Pt complex into the receptor and predicting bioactive conformers. Our results may provide valuable information to understand the mechanistic pathway of drug delivery and to pharmacological behavior of drug.  相似文献   
44.
An efficient, high yielding and environmentally benign strategy to the synthesis of new 2-amino-3-cyano-4-H-chromene derivatives, via one-pot three-component reaction involving malononitrile, various α- or β-naphthol and appropriate aromatic aldehydes including 2-chloroquinoline-3-carbaldehydes in the presence of morpholine in water, was achieved. During the development of the synthesis five new chromene derivatives were fruitfully synthesized. It was found that employing this approach, aromatic aldehydes bearing electron-withdrawing groups give higher yields of the corresponding products in shorter reaction times. This observation was in agreement with topological analysis of calculated electron density functions using density functional theory and quantum theory of atoms in molecules approaches.  相似文献   
45.
We report a new strategy to immobilize a bromine source on the surface of magnetic Fe3O4 nanoparticles (Fe3O4 MNPs-DETA/Benzyl-Br3) leading to a magnetically recoverable catalyst, which exhibits high catalytic efficiency in oxidative coupling of thiols to the disulfides (89–98%). The Fe3O4 MNPs-DETA/Benzyl-Br3 catalyst was fabricated by anchoring 3-chloropropyltrimethoxysilane (CPTMS) on magnetic Fe3O4 nanoparticles, followed with N-benzylation and reaction with bromine in tetrachloridecarbon. The resulting nanocomposite was analyzed by a series of characterization techniques such as FT-IR, SEM, TGA, VSM and XRD. The catalyst could be recovered via magnetic attraction and could be recycled at least 5 times without appreciable decrease in activity.  相似文献   
46.
Different derivatives of a novel heterocyclic system, i.e., pyrimido[4,5‐d] [1,2,4]triazolo[4,3‐a]pyrimidine, are synthesized in moderate‐to‐good yields. These compounds exhibit excellent photochromism upon photoirradiation. The photophysical characterizations of these new compounds were evaluated by UV/VIS absorption and fluorescence emission studies. The emission spectra in various solvents are also presented and discussed. The changes are due to the intramolecular H‐bonding of pyrimido‐triazolo‐pyrimidine with H2O, and photoinduced electron and general solvent effect. These compounds display high fluorescence quantum yields and are reported as new fluorophores.  相似文献   
47.
Several derivatives of the new pyridazino[4,3‐e][1,3,4]oxadiazine ring system were prepared, and their antibacterial evaluations were performed on four different Gram‐negative and Gram‐positive bacteria. J. Heterocyclic Chem., (2010).  相似文献   
48.
49.
Molecular Diversity - New selenopheno[2,3-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives have been synthesized via Dimroth rearrangement by cyclocondensation of...  相似文献   
50.
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