the corresponding O-benzyloxime (2b) are easily esterified in high yield by beta-bromo alcohols. The resulting esters undergo radical cyclization to alpha-(2,2-diphenylhydrazino)- or alpha-[(phenylmethoxy)amino]lactones on treatment with tributyltin hydride. Esters for radical cyclization were also made using a beta-(phenylseleno) alcohol and an enol ether. Several derivatives of glyoxylic acid were
乙醛酸二苯hydr(2a)和相应的O-苄基
肟(2b)容易被β-
溴醇高产率地酯化。用氢化三
丁基锡处理后,所得酯经历自由基环化成α-(2,2-二苯基
肼基)-或α-[((
苯基甲氧基)
氨基]内酯。还使用β-(苯基
硒代)醇和烯醇醚制备用于自由基环化的酯。评估了
乙醛酸的几种衍
生物,但没有一个比2a或2b有效。
亚胺28是通过间接途径制备的。它会通过氮取代基(28-> 30)的取代而经历自由基环化反应,从而可以通过环化产物的酸
水解生成α-
氨基内酯。