【药物名称】Etazolate, SQ-20009(hydrochloride)
化学结构式(Chemical Structure):
参考文献No.47605
标题:Hydrazines and hydrazones of pyrazolopyridine carboxylic acids and esters
作者:Hoehn, H.; Chasin, M. (Bristol-Myers Squibb Co.)
来源:DE 2028869; GB 1317797; NL 165461C; NL 7008768
合成路线图解说明:

The condensation of 1-ethyl-5-aminopyrazole (I) with diethyl ethoxymethylenemalonate (II) by heating at 120 C gives diethyl [((1-ethyl-5-pyrazolyl)amino)methylene]malonate (III), which by heating at 235-5 C in diphenyl ether is converted into ethyl 1-ethyl-4-hydroxy-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (IV). The reaction of (IV) with ethyl iodide (A) and K2CO3 in DMF affords ethyl 1-ethyl-4-ethoxy-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (V), which is condensed with hydrazine in refluxing ethanol with ZnCl2 yielding ethyl 1-ethyl-4-hydrazino-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (VI). Finally, (VI) is condensed with refluxing acetone (B).

参考文献No.65187
标题:Etazolate
作者:Chatterjee, S.S.
来源:Drugs Fut 1977,2(4),243
合成路线图解说明:

The condensation of 1-ethyl-5-aminopyrazole (I) with diethyl ethoxymethylenemalonate (II) by heating at 120 C gives diethyl [((1-ethyl-5-pyrazolyl)amino)methylene]malonate (III), which by heating at 235-5 C in diphenyl ether is converted into ethyl 1-ethyl-4-hydroxy-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (IV). The reaction of (IV) with ethyl iodide (A) and K2CO3 in DMF affords ethyl 1-ethyl-4-ethoxy-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (V), which is condensed with hydrazine in refluxing ethanol with ZnCl2 yielding ethyl 1-ethyl-4-hydrazino-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (VI). Finally, (VI) is condensed with refluxing acetone (B).

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