92-43-3Relevant articles and documents
A convenient one-pot synthesis of 1-aryl-substituted 4-iodopyrazol-3-ols via aromatisation and oxidative iodination reactions
Liu, Jingjing,Yang, Shanguang,Dong, Ruimei,Jin, Zhudan,Wang, Mingliang
, p. 24 - 27 (2018/02/28)
A convenient and economical one-pot synthesis of a series of new 1-aryl-substituted 4-iodopyrazole-3-ols from easily available pyrazolidin- 3-ones in the presence of sodium iodide, 30% solution of hydrogen peroxide and a catalytic amount of sulfuric acid in dichloromethane via aromatisation and oxidative iodination reactions are described. This protocol has the advantages of high atom economy, costeffectiveness, short reaction time and environmental friendliness.
Biguanide derivatives, pharmaceutical composition, preparation method and application
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Paragraph 0035-0037, (2019/01/14)
The invention belongs to the field of medicine and particularly relates to biguanide derivatives, pharmaceutical composition, a preparation method and an application. The biguanide derivatives are compounds with the structure shown in the description, or pharmaceutically acceptable salts, solvates, isomers, esters and predrugs of the compounds. The compounds can remarkably inhibit proliferation and migration of tumor cells, IC50 is greatly lower than that of metformin and phenformin before derivatization, the compound 11 has the highest activity, and activity of the compounds in UMUC3, T24 andA2780 cells is more than 300-800 times that of metformin, and the compounds have good application prospect in antitumor drugs.
DMF-catalyzed direct and regioselective C-H functionalization: Electrophilic/nucleophilic 4-halogenation of 3-oxypyrazoles
Liu, Yuanyuan,He, Guangke,Chen, Kai,Jin, Yin,Li, Yufeng,Zhu, Hongjun
supporting information; experimental part, p. 5323 - 5330 (2011/11/13)
A novel, straightforward, and highly regioselective 4-chlorination of 3-oxypyrazole derivatives in boiling thionyl chloride (SOCl2) in the presence of catalytic N,N-dimethylformamide (DMF) has been developed. This reaction likely proceeds through a DMF-catalyzed electrophilic/nucleophilic chlorination mechanism and involves electrophilic attack by SOCl2 and nucleophilic substitution by Cl- as the key steps. Based on this mechanism, the corresponding 4-bromination and 4-iodination of 3-oxypyrazoles have also been achieved in good yield by adding Br- and I -, respectively, to the reaction system. This halogenation method enables quick access to many original 4-halo-3-oxypyrazole series. A novel DMF-catalyzed electrophilic/nucleophilic 4-halogenation of 3-oxypyrazole derivatives has been developed. This halogenation procedure provides quick access to many novel 4-halo-3-oxypyrazole series.