Lemire Alexandre, Grenon Michel, Pourashraf Mehrnaz, Charette André B
Département de Chimie, Université de Montréal, P.O. Box 6128, Station Downtown, Montréal, Québec, Canada H3C 3J7.
Org Lett. 2004 Sep 30;6(20):3517-20. doi: 10.1021/ol048624n.
[reaction: see text] The addition of nucleophiles to 3-substituted pyridinium salts prepared from N-methylbenzamide and various pyridines has been investigated. Good to excellent regioselectivities favoring the 2,3-disubstituted 1,2-dihydropyridines were observed. The resulting 1,2-dihydropyridines led to the corresponding 2,3-disubstituted pyridines upon treatment with Mn(OAc)3/NaIO4. This methodology was also successfully applied to the enantioselective syntheses of (-)-L-733,061 and (-)-CP-99,994, two members of a new class of highly potent, nonpeptide, Substance P antagonists.
[反应:见正文] 已对亲核试剂与由N-甲基苯甲酰胺和各种吡啶制备的3-取代吡啶鎓盐的加成反应进行了研究。观察到良好至优异的区域选择性,有利于生成2,3-二取代的1,2-二氢吡啶。所得的1,2-二氢吡啶在用Mn(OAc)₃/NaIO₄处理后生成相应的2,3-二取代吡啶。该方法还成功应用于(-)-L-733,061和(-)-CP-99,994这两种新型高效非肽类P物质拮抗剂的对映选择性合成。