Simplification of antitumoral phenanthroindolizidine alkaloids: Short synthesis of cytotoxic indolizidinone and pyrrolidine analogs
作者:Javier Miguélez、Alicia Boto、Raquel Marín、Mario Díaz
DOI:10.1016/j.ejmech.2013.06.009
日期:2013.8
Hydroxylated seco-analogs of cytotoxic phenanthroindolizidine alkaloids were prepared in good yields from inexpensive 4-hydroxyproline derivatives, in just two steps. Thus, a sequential oxidative radical scission–oxidation was used for the direct conversion of the proline derivative into a 2-(2-aryl-oxoethyl)pyrrolidine with a variety of aryl and heteroaryl groups. The 4R-stereogenic center allowed
只需两步,即可从廉价的4-羟基脯氨酸衍生物中以高收率制备细胞毒性的菲咯啉吲哚嗪生物碱的羟基化类似物。因此,顺序氧化自由基的断裂-氧化被用于脯氨酸衍生物直接转化为带有各种芳基和杂芳基的2-(2-芳基-氧乙基)吡咯烷。4 R-立体异构中心可方便地进行异构体分离,并在引入新链时进行立体控制(有趣的是,2,4-顺式异构体为主)。在第二步中,环化反应提供了带有吲哚并吲哚酮核心的生物碱类似物;发生部分异构化,但异构体易于纯化。然后比较了双环吲哚并二酮和更简单的吡咯烷衍生物对致瘤性人神经元SHSY-5Y和乳腺癌MCF7细胞的细胞毒活性。所有联苯衍生物均表现出有效的活性(一种化合物在微摩尔剂量下在两种肿瘤细胞中均导致> 80%的细胞死亡),在吡咯烷酮和吲哚齐酮酮系列中可比。