申请人:THE PRESIDENT AND FELLOWS OF HARVARD COLLEGE
公开号:EP0334593A1
公开(公告)日:1989-09-27
Epoxyimines, formed with epoxyaldehydes, react via cycloaddition with amino-protected glycyl halides to provide 3-protected-amino-4-(substituted oxiranyl)azetidinones. Chiral epoxyimines from chiral epoxyaldehydes induce high levels of asymmetric induction during the cycloaddition to provide substantially one diastereomer of the 3,4-disubstituted azetidinone. For example, the epoxyimine formed with (2R,3S)-2-formyl-3-phenyloxirane and 2,4-dimethoxybenzylamine is reacted with phthalimidoacetyl chloride to provide [3R,4R,4(2S,3S)]-1-(2,4-dimethoxybenzyl)-3-phthalimido-4-(3-phenyloxiran-2-yl)-2-azetidinone.
The epoxy-substituted azetidinones are useful intermediates for β-lactam antibiotic compounds.
环氧亚胺与环氧醛形成的环氧亚胺与氨基保护的甘氨酰卤发生环化反应,生成 3-氨基保护的-4-(取代的环氧乙烷基)氮杂环丁酮。在环化反应过程中,来自手性环氧醛的手性环氧亚胺会产生高水平的不对称诱导,从而提供 3,4-二取代氮杂环丁酮的非对映异构体。例如,用 (2R,3S)-2-甲酰基-3-苯基环氧乙烷和 2,4-二甲氧基苄胺形成的环氧亚胺与邻苯二甲酰亚胺基乙酰氯反应,得到 [3R,4R,4(2S,3S)]-1-(2,4-二甲氧基苄基)-3-邻苯二甲酰亚胺基-4-(3-苯基环氧乙烷-2-基)-2-氮杂环丁酮。
环氧取代的氮杂环丁酮是β-内酰胺类抗生素化合物的有用中间体。