136582-28-0

Upstream product

• 129374-88-5 2-Hydroxy-2-((2S,3S)-3-isopropyl-2-methanesulfonyloxymethyl-4-oxo-azetidin-1-yl)-3-oxo-butyric acid benzyl ester 
• 129374-88-5 2-Hydroxy-2-((2S,3R)-3-isopropyl-2-methanesulfonyloxymethyl-4-oxo-azetidin-1-yl)-3-oxo-butyric acid benzyl ester 
• 94271-67-7 1-(2,4-Dimethoxy-benzyl)-3-isopropyl-4-oxo-azetidine-2-carboxylic acid ethyl ester 
• 124156-27-0 ethyl 3-isopropyl-1-(4-methoxyphenyl)-4-oxoazetidin-2-carboxylate 
• 129374-60-3 (3R,4S)-1-(2,4-Dimethoxy-benzyl)-4-hydroxymethyl-3-isopropyl-azetidin-2-one 
• 129374-73-8 (3R,4S)-4-Hydroxymethyl-3-isopropyl-1-(4-methoxy-phenyl)-azetidin-2-one 
• 129374-62-5 trans-3-isopropyl-4-(methylsulfonyloxymethyl)azetidin-2-one 
• 93552-78-4 benzyl 2,3-dioxobutanoate 
• 94271-67-7 ethyl (+/-)-3-isopropyl-1-(2,4-dimethoxybenzyl)-4-oxo-2-azetidinecarboxylate 
• 129374-59-0 (2S,3S)-1-(2,4-Dimethoxy-benzyl)-3-isopropyl-4-oxo-azetidine-2-carboxylic acid methyl ester 
• 129374-60-3 cis-4-hydroxymethyl-3-isopropyl-1-(2,4-dimethoxybenzyl)azetidin-2-one 
• 129374-75-0 cis-4-(Hydroxymethyl)-3-isopropyl-1-(4-methoxyphenyl)azetidin-2-one 
• 129374-62-5 cis-3-isopropyl-4-(methylsulfonyloxymethyl)azetidin-2-one 
• 94271-66-6 diethyl (+/-)-3-isopropyl-1-(2,4-dimethoxybenzyl)-4-oxo-2,2-azetidinedicarboxylate 

Downstream Products

• 129374-66-9 cis-benzyl 7-isopropyl-3-methyl-2-iso-oxacephem-4-carboxylate 
• 129374-68-1 cis-benzyl 7-isopropyl-3-methyl-2-isocephem-4-carboxylate 
• 129374-66-9 benzyl (+/-)-trans-7-isopropyl-3-methyl-2-isoxacephem-4-carboxylate 
• 129374-68-1 trans-benzyl 7-isopropyl-3-methyl-2-isocephem-4-carboxylate 

Relevant academic research and scientific papers

Simple and Condensed β-Lactams 12. Alternative Entry into the 2-Isocephem and 2-Iso-oxacephem Series.

The N-Unsubstituted-2-azetidinones ( 17a,b) react smoothly with esters of 2,3-dioxobutyric acid.In resulting intermediates (29b; 30a,b) were converted into the acetoacetates (33b; 34a,b) which were cyclized and deprotected to give the 2-iso-oxacephem- and 2-isocephem-4-carboxylic acids (1a,b) and (2a,b).