91527-75-2Relevant academic research and scientific papers
On the Mechanism of Photodehydrogenation of Aryl(hetaryl)pyrazolines in the Presence of Perchloroalkanes
Traven, Valery F.,Cheptsov, Dmitriy A.,Bulanova, Maria V.,Solovjova, Natalya P.,Chibisova, Tatyana A.,Dolotov, Sergei M.,Ivanov, Ivan V.
, p. 659 - 666 (2018/05/03)
New (1,5-diaryl-3-pyrazolinyl)coumarins have been synthesized. The compounds do not undergo keto-enol tautomeric transformations with changes in the solvent. (1,5-Diaryl-3-pyrazolinyl)coumarins provide dehydrogenation reaction under irradiation in the presence of perchloroalkanes and manifest themselves as effective photogenerators of acidity. Several aspects of photodehydrogenation mechanism have been studied. Oxygen is shown not be involved in the reaction. Polar solvents increase rate of the reaction. The measured rate constants of the photodehydrogenation reactions vary in a significant range according to the structure of pyrazoline. The data correlate with ionization potentials of pyrazolines available from DFT quantum chemical calculations. These results are discussed in terms of proposed scheme of mechanism of pyrazolines photodehydrogenation assuming formation of ion-radical and ion intermediates.
Antioxidant effectiveness generated by one or two phenolic hydroxyl groups in coumarin-substituted dihydropyrazoles
Xi, Gao-Lei,Liu, Zai-Qun
, p. 385 - 393 (2013/10/01)
A cascade operation was designed to synthesize nine coumarin-substituted dihydropyrazoles with only one or two phenolic hydroxyl groups contained. Antioxidant abilities of the obtained compounds were evaluated by inhibiting 2,2′-azobis(2-amidinopropanehydrochloride) (AAPH)-, Cu2+/ glutathione (GSH)-, and .OH-induced oxidation of DNA. It was found that less phenolic hydroxyl groups can enhance the abilities of coumarin-substituted dihydropyrazoles to protect DNA against the oxidation. Moreover, these coumarin-substituted dihydropyrazoles were employed to scavenge 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS+.), 2,2′-diphenyl-1-picrylhydrazyl radical (DPPH), and galvinoxyl radical, respectively. It was found that double phenolic hydroxyl groups were more beneficial for enhancing the abilities of coumarin-substituted dihydropyrazoles to quench the aforementioned radicals. Therefore, dihydropyrazole linked with coumarin exhibited powerful antioxidant effectiveness even in the case of less phenolic hydroxyl groups involved.
Synthesis and pharmacological evaluation of a novel series of 5-(substituted)aryl-3-(3-coumarinyl)-1-phenyl-2-pyrazolines as novel anti-inflammatory and analgesic agents
Khode, Suresh,Maddi, Veeresh,Aragade, Prashant,Palkar, Mahesh,Ronad, Pradeep Kumar,Mamledesai, Shivalingarao,Thippeswamy,Satyanarayana
experimental part, p. 1682 - 1688 (2009/06/20)
A novel series of 5-(substituted)aryl-3-(3-coumarinyl)-1-phenyl-2-pyrazolines (3a-l) were synthesized by reacting various substituted 3-aryl-1-(3-coumarinyl)propan-1-ones (2a-l) with phenylhydrazine in the presence of hot pyridine. Structures of all new s
Synthesis of 1-substituted 5-aryl-3-(3-coumarinyl)-2-pyrazolines by the reaction of 3-aryl-1-(3-coumarinyl)propen-1-ones with hydrazines
Levai, Albert,Jeko, Jozsef,Brahmbhatt
, p. 1231 - 1235 (2007/10/03)
1-Acetyl- and 1-propionyl-2-pyrazolines 11-27 have been synthesized by the reaction of (3-coumarinyl)chalcones 1-10 with hydrazine in hot acetic acid or propionic acid. While 5-aryl-3-(3-coumarinyl)-1-phenyl-2-pyrazolines 28-35 have been prepared by the r
