Studies on 4(1H)-quinazolinones. I. A convenient synthesis and some reactions of 1-phenyl-2-substituted-4(1H)-quinazolinones.
作者:KENICHI OZAKI、YOSHIHISA YAMADA、TOYONARI OINE
DOI:10.1248/cpb.28.702
日期:——
1-Phenyl-4(1H)-quinazolinones having various substituents at C-2 were synthesized and some of their reactions were examined. 1-Phenyl-2-substituted-4(1H)) quinazolinones (3) were synthesized in good yield by the reaction of 2-phenylaminobenzamide (1) with excess acid chloride under mild reaction conditions. The 2-chloroalkyl derivatives (3b-d) react with nucleophiles in a characteristic manner depending on the length of the alkyl chain. Treatment of the 2-chloromethyl derivative (3b) with nucleophiles gave 2-(substituted-methyl)-4(1H)-quinazolinones (4). Reaction of 2-chloroethyl derivative (3c) with morpholine or alcohols gave 2-(β-substituted-ethyl) derivatives (5-7) through the intermediate (8), which was identified by isolation. Allowing a chloroform solution of the 2-(γ-chloropropyl) derivative (3d) to stand afforded the 4-oxoquinazolinium salt (9a) quantitatively.
合成了在 C-2 上具有不同取代基的 1-苯基-4(1H)-喹唑啉酮,并研究了它们的一些反应。在温和的反应条件下,2-苯氨基苯甲酰胺(1)与过量的氯化酸反应合成了 1-苯基-2-取代的-4(1H)喹唑啉酮(3),收率很高。根据烷基链的长度,2-氯烷基衍生物(3b-d)与亲核剂的反应方式各不相同。将 2-氯甲基衍生物(3b)与亲核剂进行处理,可得到 2-(取代-甲基)-4(1H)-喹唑啉酮(4)。将 2-氯乙基衍生物 (3c) 与吗啉或醇反应,通过中间体 (8) 分离出 2-(β-取代-乙基)衍生物 (5-7)。将 2-(γ-氯丙基)衍生物 (3d) 的氯仿溶液静置,可定量得到 4-氧代喹唑啉鎓盐 (9a)。