合成路线1

The alkylation of 5-amino-4-cyanopyrazole (I) with n-propyl iodide led to a 4:1 inseparable mixture of regioisomers (II) and (III). This mixture was transformed into the respective imidates (IV) and (V) through refluxing in triethyl orhoformate. Subsequent addition of 2-furoic hydrazide (VI) to the nitrile group of (IV)+(V), followed by thermal cyclization in diphenyl ether at 260 C furnished the corresponding pyrazolotriazolopyrimidines. The desired regioisomer (VII) was then isolated by flash chromatography. Hydrolysis of (VII) with aqueous HCl afforded the aminopyrazole (VIII), which was further converted to the tricyclic compound (IX) by reaction with cyanamide and p-toluenesulfonic acid. Finally, coupling of (IX) with p-methoxyphenyl isocyanate (X) provided the title urea.