UR-3216
Chemical Name: 2-[5-[N-[4-(Hydroxyamidino)benzoyl]-4-nitro-L-phenylalanyl]-4,5,6,7-tetrahydro-2H-pyrazolo[4,3-c]pyridin-2-yl]acetic acid ethyl ester
CAS No. 220386-67-4
项目整合开发状态: Preclinical
项目研究机构: Ube (Originator)
合成路线:Claisen condensation of ethyl formate with N-trityl-4-piperidone (I) in the presence of NaOEt afforded the intermediate dicarbonyl enolate (II),which was subsequently condensed with ethyl hydrazinoacetate (III) to furnish the desired pyrazolopyridine (IV) accompanied by minor amounts of its regioisomer (V).After acid cleavage of the trityl protecting group of (IV),the desired isomer (VI) was isolated by recrystallization from isopropanol.Coupling of (VI) with N-Boc-L-4-nitrophenylalanine (VII) employing BOP yielded amide (VIII).Subsequent Boc group cleavage in (VIII) with trifluoroacetic acid provided amine (IX),which was coupled with 4-cyanobenzoic acid (X) using 6-chloro-2,4-dimethoxy-1,3,5-triazine (CDMT) to yield (XI).Finally,addition of hydroxylamine to the cyano group of (XI) gave the title N-hydroxyamidine.
📌 参考资料/链接:
参考文献标题:N-Acylamino acid amide cpds.and intermediates for preparation thereof
文献作者:Baba,K.; Tanaka,M.; Kuroki,Y.; Takata,K.; Motoyama,T.; Ueno,H.(Ube Industries,Ltd.)
参考来源:EP 1020467; US 6265418; WO 9906402