Syntheses of 3,4-dihydro-2H-1,4-benzoxazine-2-acetates and related compounds.
作者:YUTAKA MASUOKA、TSUNEHIKO(deceased) ASAKO、GIICHI GOTO、SHUNSAKU NOGUCHI
DOI:10.1248/cpb.34.130
日期:——
The intramolecular Michael addition of 4-(2-hydroxyanilino)-2-butenoates (3), -2-buteno-nitrile, and their 3-phenyl analogs (8) gave 3, 4-dihydro-2H-1, 4-benzoxazine-2-acetates (4), -2-acetonitrile (6), and their 3-phenyl analogs (9), respectively, in good yields. In addition, 3, 4-dihydro-3-oxo-2H-1, 4-benzoxazine-2-acetates (13) and 3, 4-dihydro-2-(p-nitrobenzyl)-2H-1, 4-benzoxazine (16) were synthesized from 2-hydroxyanilines (1) by the addition reaction of fumaric acid chloride monoester (11) and p-nitrocinnamyl bromide (14), respectively. In order to examine the biological activities of the 2H-1, 4-benzoxazine analogs, 2-(2-dialkylaminoethyl)-(18) and 2-(2, 2-diphenylethyl)-2H-1, 4-benzoxazines (19, 20) were prepared.Among the compounds synthesized, 4b and 19a showed considerable anxiolytic activity in the conflict test in rats, while the oxalates of 18a-c showed potent anticonvulsant activity.
4-(2-羟基苯氨基)-2-丁烯酸酯(3)、-2-丁烯腈及其3-苯基类似物(8)的分子内Michael加成反应,分别以良好的产率得到了3,4-二氢-2H-1,4-苯并噁嗪-2-乙酸酯(4)、-2-乙腈(6)及其3-苯基类似物(9)。此外,3,4-二氢-3-氧代-2H-1,4-苯并噁嗪-2-乙酸酯(13)和3,4-二氢-2-(对硝基苄基)-2H-1,4-苯并噁嗪(16)分别通过富马酸氯甲酸单酯(11)和对硝基肉桂基溴(14)的加成反应,从2-羟基苯胺(1)合成得到。为了考察2H-1,4-苯并噁嗪类似物的生物活性,合成了2-(2-二烷基氨基乙基)-(18)和2-(2,2-二苯基乙基)-2H-1,4-苯并噁嗪(19, 20)。在所合成的化合物中,4b和19a在小鼠冲突实验中表现出显著的抗焦虑活性,而18a-c的草酸盐则显示出强效的抗惊厥活性。