A Rapid Synthesis of 2,3,11,11a-Tetrahydro-6H-pyrazino[1,2-b]isoquinoline-1,4-diones Through an Amido Iminium Ion Cyclization
摘要:
7,10-Dimethoxy-6-methyl-2,3,11,11a-tetrahydro-6H-pyrazino[1,2-b]isoquinoline-1,4-diones (5) and (6) were syntured from glycine anhydride and 2,5-dimethoxybenzaldehyde through an amido iminium ion cyclization reaction.这种构建四氢异喹啉环的方法将有助于合成黄樟素类化合物。
在TMSOTf作为催化剂存在下,将醛二甲基乙缩醛(此处为乙醛)加至1-乙酰基-3-芳基甲基哌嗪-2,5-二酮(此处为2,5-二甲氧基苯基)的未分离的O-三甲基甲硅烷基衍生物中相应的N-甲氧基烷基衍生物,在酸性条件下,通过涉及N-酰基阳离子(6 S *,11a R *)-2-乙酰基-6-烷基-3的Pictet-Spengler型反应,具有很高的收率, 6,11,11a-tetrahydro-2 H -pyrazino [1,2- b]异喹啉-1,4-二酮。11a-立体异构体的差向异构化是通过自由基溴化,自发氢溴酸盐消除和催化氢化来完成的,得到(6 S *,11a S *)异构体。我们提出这些化合物作为四氢异喹啉抗肿瘤抗生素的前体。
Improvements in Aldol Reactions with Diketopiperazines
作者:Juan Francisco González、Elena de la Cuesta、Carmen Avendaño
DOI:10.1081/scc-120030746
日期:2004.12.31
Precipitation of products by using dichloromethane as solvent permits an efficient aldol-type reaction between 1,4-diacetyl-2,5-piperazinedione and aromatic aldehydes catalyzed by K'BuO/'BuOH independently of the electrophilic character of the aryl ring. A simple method to obtain 3-methyl-2,4,5-trimethoxybenzaldehyde is also reported.
ONA, CHI WI;LEE, HONG CHANG, AUSTRAL. J. CHEM., 43,(1990) N, C. 773-775
作者:ONA, CHI WI、LEE, HONG CHANG
DOI:——
日期:——
YOKOI, TOSHIO;YANG, LI-MING;YOKOI, TOMIKO;WU, RONG-YANG;LEE, KUO-HSIUNG, J. ANTIBIOTICS, 41,(1988) N 4, 494-501