96035-98-2Relevant articles and documents
CARBAPENEM COMPOUNDS
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Page/Page column 52, (2017/10/13)
This invention relates to carbapenem compounds, their stereoisomers, pharmaceutically acceptable salts or N-oxides thereof, which may be useful for the treatment of bacterial infections, particularly drug-resistant bacterial infections, as well as the pro
Highly stereocontrolled synthesis of the 1β-methylcarbapenem key intermediate by the Reformatsky reaction of 3-(2-bromopropionyl)-2-oxazolidone derivatives with a 4-acetoxy-2-azetidinone
Ito,Sasaki,Tamoto,Sunagawa,Terashima
, p. 2801 - 2820 (2007/10/02)
The key synthetic intermediate (4) of 1β-methylcarbapenems (1~3) was efficiently synthesized by employing highly stereocontrolled Reformatsky reaction (C4-alkylation) of 3-(2-bromopropionyl)-2-oxazolidone derivatives (6) with (3R,4R)-4-acetoxy-3-[(R)-1-(t-butyldimethylsilyloxy)ethyl]-2-azetidino ne (5) in the presence of zinc dust followed by removal of 2-oxazolidone moieties. The best diastereoselectivity (β:α = 95:5) could be realized by uses of sterically crowded achiral 2-oxazolidone derivatives such as 4,4-dimethyl-, 4,4,5,5-tetramethyl, and 4,4-dibutyl-5,5-pentamethylene-2-oxazolidone and higher reaction temperatures (refluxing tetrahydrofran). The remarkable diastereoselectivities observed for the Reformatsky reactions could be explained by means of the weakly chelating transition state models.
A highly stereoselective synthesis of a key intermediate of 1β-methylcarbapenems employing the Reformatsky reaction of 3-(2-bromopropionyl)-2-oxazolidone derivatives
Ito,Terashima
, p. 6625 - 6628,6625-6628 (2007/10/02)
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