2,3-Dihydro-4H-1,3-oxazin-4-ones, Novel Auxiliaries for the Stereoselective Synthesis of 1β-methylcarbapenems
作者:Do K. Pyun、Won J. Jeong、Hee J. Jung、Jae H. Kim、Jin S. Lee、Cheol H. Lee、Bong J. Kim
DOI:10.1055/s-2001-18778
日期:——
as efficient auxiliaries for the stereoselectivesynthesis of β-methylcarbapenem intermediate 2. Reformatsky-type reactions of 4-acetoxyazetidinone with α-bromopropionyl dihydrooxazinone 10 provided β-methylazetidinones 4 in high diastereoselectivities. The auxiliaries 9 were also easily removed in the Dieckmann cyclization leading to β-methylcarbapenem skeletons. Practical synthesis of β-methylenolphosphates