94944-07-7

Upstream product

• 119067-27-5 (3S,4S)-4-Benzoyl-3-((S)-1-hydroxy-ethyl)-1-(4-methoxy-phenyl)-azetidin-2-one 
• 94944-06-6 (2R,3R)-N-(benzoyl)methyl-N-4-methoxyphenyl-2,3-epoxybutanamide 
• 5883-82-9 2-((4-methoxyphenyl)amino)-1-phenylethanone 
• 104-94-9 4-methoxy-aniline 
• 70-11-1 α-bromoacetophenone 
• 1074-12-0 phenylglyoxal hydrate 
• 62558-62-7 (E)-2-((4-methoxyphenyl)imino)-1-phenylethanone 
• 118990-84-4 (3S,4R)-4-benzoyl-3-<1(S)-<(triisopropylsilyl)oxy>ethyl>-1-(p-methoxyphenyl)azetidin-2-one 
• 84939-32-2 2R,3R-2,3-epoxybutyric acid-p-methoxyphenylamide 

Downstream Products

• 104401-70-9 (3S,4S)-4-benzoyl-3-<1-(R)-hydroxyethyl>-2-azetidinone 
• 94944-11-3 (3R,4R)-4-benzoyloxy-3-<1-(R)-hydroxyethyl>-2-azetidinone 
• 94944-08-8 (3S,4S)-4-Benzoyl-3-[(R)-1-(tert-butyl-dimethyl-silanyloxy)-ethyl]-1-(4-methoxy-phenyl)-azetidin-2-one 
• 94944-09-9 [3S-[3α(S*),4β]]-4-benzoyl-3-[1-[[[(1,1-dimethyl-ethyl)dimethyl]silyl]oxy]ethyl]-2-azetidinone 

Relevant academic research and scientific papers

Preparation method of azetidinone compound and preparation method 4 - acyloxy-azetidinone compound

The invention provides a preparation method of a azetidinone compound and a preparation method of 4 - acyloxy-azetidinone compound. The preparation method comprises the following steps S1, an epoxy amide compound reacts with I alkali reagents to form a ring reaction, and first 1st reaction systems are obtained. Step S2: The first reaction system is subjected to hydroxyl protection reaction with a raw material including a silanization reagent and a nitrogen-containing basic organic matter to obtain second reaction systems. In step S3, second reaction system and second base reagent are subjected to isomerization reaction to obtain the azetidinone compound, wherein the epoxy amide compound has the structure shown VI, the separation process of the isomer product of the structure shown II and formula III IV is avoided, and the selectivity and yield of the azetidinone compound are improved.

Synthesis of (1′R,3S,4S)-3-[1′-(tert-butyldimethylsilyloxy) ethyl]-4-(cyclopropylcarbonyloxy)azetidin-2-one

The novel carbapenem precursor 1e has been synthesized from L-threonine, cyclopropyl methyl ketone and benzhydrylamine (for the introduction of the azetidinone N-protecting group). Two independently prepared building blocks - sodium (2R,3R)-2,3-epoxybutyrate as a mixed salt with NaBr (2b) and N-(benzhydryl)aminomethyl cyclopropyl ketone (4e) - were coupled to give (2R,3R)-N-(benzhydryl)-N-(2-cyclopropyl-2-oxoethyl)-2,3-epoxybutyramide (8e). This key intermediate gave a regio- and stereoselective C3-C4 ring closure on LiHMDS treatment in THF at 0°C to yield (1′R,3S,4S)-4- cyclopropylcarbonyl-1-diphenylmethyl-3-(1-hydroxyethyl)azetidin-2-one (13e). N-Deprotection of 13e was performed by photochemical bromination and subsequent hydrolysis. The resulting (1′R,3S,4S)-4-(cyclopropylcarbonyl)-3-(1- hydroxyethyl)azetidin-2-one (23e) reacted in a Baeyer-Villiger oxidation with a total control of the regioselectivity (due to the poor migratory aptitude of the cyclopropyl group) to furnish (1′R,3S,4S)-3-(1-hydroxyethyl)-4- (cyclopropylcarbonyloxy)azetidin-2-one (24e), subsequent O-silylation achieving the total synthesis of 1e (title compound). Wiley-VCH Verlag GmbH & Co. KGaA, 2006.

Process for preparing azetidinones

A process for preparing azetidinones of the formula: STR1 wherein R1 is an amino-protecting group and R2 is alkyl or aryl, which comprises reacting compounds of the formulae (VIII) and (IX) STR2 wherein L is a leaving group. The prod