40257-94-1Relevant articles and documents
Synthesis of arylhydrazone-based molecular switches using aryldiazonium silica sulfate nanocomposites and analysis of their isomerization
Abbaspourrad, Alireza,Aghaei, Hamidreza,Chermahini, Alireza Najafi,Khazdooz, Leila,Soltani, Solmaz,Zarei, Amin
, (2021/06/26)
A fast and efficient method for the synthesis of a series of arylhydrazones by reacting aryldiazonium silica sulfate nanocomposites with malononitrile, ethyl acetoacetate and dimedone is reported. All reactions were carried out in water at room temperature and the corresponding products were obtained in 77–87% yields. The existence of two kinds of intramolecular hydrogen bonds in the arylhydrazones synthesized using ethyl acetoacetate enables these compounds to be switched by rotation about the hydrazone C[dbnd]N bond, which leads to a reversible isomerization between their E and Z configurations. This switching can be controlled by changing the polarity of the solvents. The E/Z ratio of each synthesized compound was studied in CHCl3 and DMSO. The ratios of the E/Z were calculated using 1H NMR data in both CDCl3 and DMSO?d6, and used to calculate ΔG° for the E-Z isomerization of each synthesized compound in these two solvents. By changing the solvent from CHCl3 to DMSO, the E/Z ratios decreased. The results demonstrated that the ΔG° values for the formation of Z isomers were more negative than those of the E isomers in DMSO. This is why Z isomers are more stable than E isomers in DMSO. The results of density functional theory (DFT) calculations at B3LYP/6–311++G (d,p) level of theory, were in agreement with the experiments and confirmed the increased stability of Z isomers in DMSO. In most cases, DFT calculation in CDCl3 and DMSO indicate that the dipole moments of the Z isomers are significantly higher than those of the E isomers. Finally, the effect of temperature on the E-Z isomerization was studied using dynamic 1H NMR. The findings demonstrated that temperature does not have any significant effect on the E-Z isomerization in CDCl3 and DMSO?d6.
Computer-aided molecular design of pyrazolotriazines targeting glycogen synthase kinase 3
Sciú, M. Lourdes,Sebastián-Pérez, Victor,Martinez-Gonzalez, Loreto,Benitez, Rocio,Perez, Daniel I.,Pérez, Concepción,Campillo, Nuria E.,Martinez, Ana,Moyano, E. Laura
, p. 87 - 96 (2018/10/31)
Numerous studies have highlighted the implications of the glycogen synthase kinase 3 (GSK-3) in several processes associated with Alzheimer’s disease (AD). Therefore, GSK-3 has become a crucial therapeutic target for the treatment of this neurodegenerative disorder. Hereby, we report the design and multistep synthesis of ethyl 4-oxo-pyrazolo[4,3-d][1–3]triazine-7-carboxylates and their biological evaluation as GSK-3 inhibitors. Molecular modelling studies allow us to develop this new scaffold optimising the chemical structure. Potential binding mode determination in the enzyme and the analysis of the key features in the catalytic site are also described. Furthermore, the ability of pyrazolotriazinones to cross the blood–brain barrier (BBB) was evaluated by passive diffusion and those who showed great GSK-3 inhibition and permeation to the central nervous system (CNS) showed neuroprotective properties against tau hyperphosphorylation in a cell-based model. These new brain permeable pyrazolotriazinones may be used for key in vivo studies and may be considered as new leads for further optimisation for the treatment of AD.
Synthesis, absorption properties and biological evaluation of some novel disazo dyes derived from pyrazole derivatives
Sener, Nesrin,Sener, Izzet,Yavuz, Serkan,Karci, Fikret
, p. 3003 - 3012 (2015/12/11)
In this study, 20 novel disazo dyes containing pyrazole derivatives were synthesized by a convenient method. Diazotized aniline and some aniline derivatives were reacted with malononitrile to give 2-arylazomalononitrile derivatives 1(a-e). The synthesized 2-arylazomalononitrile derivatives were reacted with hydrazine and phenyl hydrazine to afford the corresponding 3,5-diamino-4-arylazo-1 H-pyrazole 2(a-e) and 3,5-diamino-4-arylazo-1-phenylpyrazole 3(a-e). Diazotized compounds of 2(a-e)and 3(a-e) reacted with ethylacetoacetate to give 4-arylazo-3-amino-1 H-pyrazole-5-ylazo-ethylacetoacetate 4(a-e) and 4-arylazo-3-amino-1-phenylpyrazole-5-ylazo-ethylacetoacetate 7(ae). The obtained 4(a-e) and 7(a-e) were reacted with hydrazine and phenyl hydrazine to give disazo dyes 5(a-e), 6(a-e), 8(a-e) and 9(a-e), respectively. The synthesized disazo dyes were characterized by spectroscopic techniques as well as elemental analysis. The solvatochromic behaviours of these dyes in various solvents were examined. Acid-base effects on the absorption maxima of the dyes were also reported. Antimicrobial activities of the synthesized novel disazo dyes were investigated.
