18048-64-1Relevant articles and documents
Iodine-catalyzed oxidative annulation: Facile synthesis of pyrazolooxepinopyrazolones: Via methyl azaarene sp3C-H functionalization
Zhang, Xin-Ke,Miao, Xiao-Yu,Zhou, Yu,Wang, Yu-Mei,Song, Ying-Chun,Liu, Hang,Xiong, Yi-Lu,Li, Ling-Yu,Wu, An-Xin,Zhu, Yan-Ping
supporting information, p. 1236 - 1242 (2022/02/19)
An iodine-catalyzed methyl azaarene sp3 C-H functionalization has been developed for the synthesis of a seven-membered O-heterocyclic architecture containing three different heterocyclic aromatic hydrocarbons. This method can be applied to a wide range of substituted methyl azaarenes and diverse 2,4-dihydro-3H-pyrazol-3-ones, and brings about the efficient preparation of 2,9-dihydrooxepino[2,3-c:6,5-c′]dipyrazol-3(7H)-ones in high yields with the merits of low catalyst loading, good functional group tolerance and metal-free conditions.
Preparation method of eltrombopag intermediate and preparation method of eltrombopag diethanolamine salt
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Paragraph 0051-0052; 0054, (2021/06/22)
The invention provides a preparation method of an eltrombopag intermediate and a preparation method of eltrombopag diethanolamine salt, and relates to the technical field of medicinal chemistry. According to the preparation method of the eltrombopag intermediate, p-bromophenol is taken as a raw material, and the problem of poor selectivity of nitration reaction is solved. After iodination, the coupling reaction yield of the intermediate compound as shown in a formula (I) and phenylboronic acid is high. Subsequently reduction reaction is carried out, the debromination reaction is complete, the yield is 90% or more, the refining is simpler, and the synthesis yield of the compound of the formula (I) is higher and the operation is simple. Through the improvement, the yield of the key compound shown as the formula (I) is relatively high, the subsequent treatment operation is simple, the process is easy for amplified production, the yield of the whole synthesis process of the eltrombopag diethanolamine salt is 48.1%, the operation is simple, less three wastes are generated, and the synthesis process is suitable for amplified production.
Metal-Free Direct C–H Thiolation and Thiocyanation of Pyrazolones
Kittikool, Tanakorn,Yotphan, Sirilata
supporting information, (2020/02/13)
Metal-free approach for direct C–H thiolation and thiocyanation of N-substituted pyrazolones with disulfides and thiocyanate salts, respectively, are developed. These reactions allow the C–S bond coupling to proceed effectively under mild conditions, providing useful and convenient methods for preparation of a series of 4-thio-substituted pyrazolone analogues, which have potential applications in organic, medicinal and material chemistry. Preliminary mechanistic investigation suggested that radical processes are likely to involve in these transformations.