作者:Michael A. Lyon、Simon Lawrence、David J. Williams、Yvette A. Jackson
DOI:10.1039/a809203f
日期:——
Synthesis of 9-phenyl-7H-benzothiazolo[4,5,6-ij][2,7]naphthyridin-7-one 11, an analogue of kuanoniamine A 8, is described. The synthesis involves a hetero Diels–Alder reaction of crotonaldehyde dimethylhydrazone with 4,7-dioxo-2-phenylbenzothiazole 18a or with 6-bromo-4,7-dioxo-2-phenylbenzothiazole 18b followed by annelation of the appropriate adduct. Reaction with 18a produced two sets of regioisomers—the thiazoloquinolinediones 19a,b, and the dimethylamino dioxobenzothiazoles 23a,b. The structure of 23b was determined by single-crystal X-ray structure analysis. Verification of the other structures, and methods used to improve the Diels–Alder reaction are described.
本研究描述了 9-苯基-7H-苯并噻唑并[4,5,6-ij][2,7]萘啶-7-酮 11 的合成,它是宽胺 A 8 的类似物。合成过程包括巴豆醛二甲基腙与 4,7-二氧代-2-苯基苯并噻唑 18a 或 6-溴-4,7-二氧代-2-苯基苯并噻唑 18b 的杂 Diels-Alder 反应,然后对相应的加合物进行炔化反应。与 18a 反应产生了两组区域异构体--噻唑喹啉二酮 19a,b 和二甲基氨基二氧代苯并噻唑 23a,b。23b 的结构是通过单晶 X 射线结构分析确定的。文中还介绍了其他结构的验证以及改进 Diels-Alder 反应的方法。