Taxane diterpenes 5: Synthesis of the A- and C-rings: An unusual rearrangement of an N-hydroxyimino lactone
作者:Philip Magnus、Nicholas Westwood、Mark Spyvee、Christopher Frost、Patrick Linnane、Francis Tavares、Vince Lynch
DOI:10.1016/s0040-4020(99)00305-1
日期:1999.5
Ring A of taxol was synthesized from the bromodiene 5 and acryloyl chloride to give 6, which was resolved by separation of diastereomers 7. Allylic oxidation of 7 gave 8, which on deprotection, esterification and reduction gave 11. Heating 11 followed by reduction and protection gave 13. The C-ring component was made using asymmetric Birch reduction methodology combined with standard functional group
由溴二茂烯5和丙烯酰氯合成紫杉醇环A得到6,通过分离非对映异构体7拆分。7的烯丙基氧化得到8,经脱保护,酯化和还原反应得到11。加热11,然后还原和保护得到13。C环组件是使用不对称的Birch还原方法与标准官能团操作相结合制成的,给出了28个。将13和28合并得到29,将其转换为33。热解33不会产生一氧化氮,而是离子化为氧二烯基阳离子,最终导致34。