作者:M.-Lluïsa Bennasar、Cecília Juan、Joan Bosch
DOI:10.1039/b007814j
日期:——
fluoro- pyridinium triflate 7, followed by oxidation–hydrolysis of the resultant 2-fluoro-1,4-dihydropyridine 8b afforded pyridone 9b, from which 20-deoxycamptothecin (11), a known precursor of camptothecin, was synthesized by a radical cyclization–desulfurization, with subsequent elaboration of the lactone E ring by chemoselective reduction.
将衍生自α-(甲基
硫烷基)
丁酸异丙酯的烯醇化物加入到 N-(
喹啉甲基)-2-
氟吡啶鎓
三氟甲磺酸盐 7 中,然后氧化
水解生成的 2-
氟-1,4-
二氢吡啶 8b,得到
吡啶酮 9b,从中通过自由基环化-脱
硫合成已知的
喜树碱前体 20-脱氧
喜树碱 (11),随后通过
化学选择性还原制备内酯 E 环。