Total synthesis of 12-methoxydihydrochelerythrine and anti-tumour activity of its quaternary base: toward an efficient synthetic route for 12-alkoxybenzo[c]phenanthridine bases via naphthoquinone monooxime from 2-benzofuranyl-1-tetralone derivative
作者:Toshiko Watanabe、Yoshiaki Ohashi、Rie Yoshino、Naoko Komano、Miyuki Eguchi、Sakiko Maruyama、Tsutomu Ishikawa
DOI:10.1039/b304216m
日期:——
features an efficient route to a 12-alkoxybenzo[c]phenanthridine skeleton via naphthoquinone monooxime 11 as a key compound. Starting from 7-methoxy-2-methylbenzo[b]furan (9), 3-aryl-1-tetralone 10 was synthesised, followed by aromatisation to 3-aryl-1-naphthol 17. After oxidative cleavage of the furan ring, basic nitrosation of naphthol 22 gave the naphthoquinone 11. The benzo[c]phenanthridine skeleton
描述了从整叶西兰花(Bocconia integrifolia)中分离的12-甲氧基二氢白屈菜红碱(6)的简明全合成。该合成的特征是通过萘醌一肟11作为关键化合物,可高效合成12-烷氧基苯并[c]菲啶骨架。从7-甲氧基-2-甲基苯并[b]呋喃(9)开始,合成了3-芳基-1-四氢萘酮10,然后芳构化为3-芳基-1-萘酚17。呋喃环被氧化裂解后,碱性萘酚22的亚硝化得到萘醌11。11的还原环化形成苯并[c]菲啶骨架。内酰胺部分在23中脱氧得到正碱基32,甲基32在还原条件下甲基化得到目标二氢碱基6(从苯并呋喃9提取23步,总产率为10%)。相应的四元碱基7对癌细胞系显示出中等的抗肿瘤活性。NCI-H460:IC50 4.5 microM; MDA-MB-231:IC50 1.2 microM。通过将7与白屈菜红碱(35)(IC50 5.3 microM)进行比较,将甲氧基引入苯并[c]菲啶骨架