Synthesis of (−) cephalosporolide E and (+) cephalosporolide F utilizing the vinylogous Mukaiyama type reaction with an α-chloro sulfide
作者:Sadagopan Raghavan、Javed Sardar Patel、K. V. S. Ramakrishna
DOI:10.1039/c6ra13861f
日期:——
synthesis of cephalosporolide E and F is described utilizing diastereoselective reduction of a propargylic ketone using a Noyori catalyst to create the C6 carbinol stereogenic center. A vinylogous silylketene acetal addition to an α-chloro sulfide is exploited for stereoselective carbon–carbon bond formation and introduction of the butenolide moiety. Oxidative radical cyclization is utilized for the creation
A concise protecting-group-free synthesis of cephalosporolides E and F
作者:Dipali A. Chaudhari、Pullaiah Kattanguru、Rodney A. Fernandes
DOI:10.1039/c5ra06991b
日期:——
A concise protecting-group-free synthesis of cephalosporolides E and F has been described. The key steps involve the one-pot conversion of L-mannonic-γ-lactone to γ-vinyl-β-hydroxy-γ-lactone, cross-metathesis and Wacker-type oxidative spiroketalization. The internal olefin served as a latent keto functionality with excellent delivery of a regioselective keto group for spiroketalization. The synthetic
The Stereoselective Total Synthesis of the Elusive Cephalosporolide F
作者:Leonardo Xochicale-Santana、Omar Cortezano-Arellano、Bernardo A. Frontana-Uribe、Victor M. Jimenez-Pérez、Fernando Sartillo-Piscil
DOI:10.1021/acs.joc.3c00251
日期:——
Here we report a seven-step protecting-group-free stereoselectivetotalsynthesis of the elusive (+)-cephalosporolide F from d-glucose. A microwave-assisted reaction between the Meldrum’s acid and the d-glucose to the respective octono-1,4-lactone derivative, and a low temperature visible-light photoredox spirocyclization of a chiral N-alkoxyphthalimide to ceph F, are the two key chemical reactions
在这里,我们报告了从d -葡萄糖合成难以捉摸的 (+)-头孢内酯 F 的七步无保护基立体选择性全合成。Meldrum 酸和d -葡萄糖之间的微波辅助反应生成相应的 octono-1,4-内酯衍生物,以及手性N -烷氧基邻苯二甲酰亚胺低温可见光光氧化还原螺环化生成头孢 F,是两种关键化学物质在环保过程中实现这一前所未有的壮举的反应。