A Convergent Synthetic Route to (+)-Dynemicin A and Analogs of Wide Structural Variability
作者:Andrew G. Myers、Norma J. Tom、Mark E. Fraley、Scott B. Cohen、David J. Madar
DOI:10.1021/ja9703741
日期:1997.7.1
yield of 85% and an overall yield of 2−3%. Key features of this sequence include the coupling of the enol triflate 11 and the arylboronic acid 10 (90%), the thermal deprotection/internal amidation of the coupling product 18 (84%), the use of 2-chloropyridine as an economical alternative to 2,6-di-tert-butylpyridine to promote the reaction of the quinolone 9 and triflic anhydride (85%), the highly stereoselective
描述了对 (+)-dynemicin A (1) 的对映选择性合成路线,其中关键和最后一步是醌亚胺 6 与异苯并呋喃 107 的 Diels-Alder 环加成,然后进行氧化处理以提供 (+)-1以 40% 的收率。合成路线始于乙酰乙酸(-)-薄荷酯和巴豆酸反式乙酯缩合形成结晶环己二酮 14,然后分 23 步转化为对映体纯的醌亚胺 6,平均产率为 85%,总产率产率为 2-3%。该序列的关键特征包括烯醇三氟甲磺酸酯 11 和芳基硼酸 10 (90%) 的偶联、偶联产物 18 (84%) 的热脱保护/内部酰胺化、使用 2-氯吡啶作为经济的替代品2、