80926-64-3

Upstream product

• 16869-24-2 4-nitrobenzyl bromoacetate 
• 18162-48-6 tert-butyldimethylsilyl chloride 
• 75939-72-9 racemic (3S,4R)-3-((R)-1-hydroxyethyl)-4-triphenylmethylthio-2-azetidinone 
• 87996-98-3 Silver; (2S,3R)-3-[(S)-1-(tert-butyl-dimethyl-silanyloxy)-ethyl]-1-(4-nitro-benzyloxycarbonylmethyl)-4-oxo-azetidine-2-thiolate 
• 83807-48-1 {(2R,3S)-3-[(R)-1-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-2-chloro-4-oxo-azetidin-1-yl}-(4-oxo-[1,3]dithietan-2-ylidene)-acetic acid 4-nitro-benzyl ester 
• 82864-29-7 (3S,4R)-3-<(R)-1-tert-Butyldimethylsilyloxyethyl>-4-methylthio-2-oxoazetidine 
• 83860-44-0 {(2R,3S)-3-[(R)-1-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-2-methylsulfanyl-4-oxo-azetidin-1-yl}-(4-oxo-[1,3]dithietan-2-ylidene)-acetic acid 4-nitro-benzyl ester 
• 88816-45-9 4-Nitrobenzyl 3,3-di(acetylthio)-2-[(3S,4R)-4-ethylthio-3-(1'(R)-{dimethyl-{2-methylprop-2-yl}silyloxy}ethyl)-2-azetidinon-1-yl]propenoate 
• 88816-47-1 4-Nitrobenzyl 3,3-di(acetylthio)-2-[(3S,4R)-4-chloro-3-(1'(R)-{dimethyl-{2-methylprop-2-yl}silyloxy}ethyl)-2-azetidinon-1-yl]propenoate 
• 87996-93-8 racemic (3S,4R)-3-((R)-1-(t-butyldimethylsilyloxy)ethyl)-4-triphenylmethylthio-2-azetidinone 
• 87996-95-0 racemic (3S,4R)-1-(p-nitrobenzylcarbonyl)methyl-3-((R)-1-t-butyldimethylsilyloxyethyl)-4-triphenylmethylthio-2-azetidinone 
• 87996-99-4 racemic (3S,4R)-1-(p-nitrobenzyloxycarbonyl)methyl-3-<((R)-1-t-butyldimethylsilyloxy)-ethyl>-4-phenoxy(thiocarbonyl)thio-2-azetidinone 

Downstream Products

• 83807-51-6 (5S,6S)-6-[(R)-1-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-3-cyanomethylsulfanyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester 
• 81878-57-1 (5R,6S)-3-Cyanomethylsulfanyl-6-((R)-1-hydroxy-ethyl)-7-oxo-4-thia-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester 
• 81864-87-1 (5R,6S)-6-[(R)-1-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-3-cyanomethylsulfanyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester 

Relevant academic research and scientific papers

Stereoselective Synthesis of a (5R,6S)-6--2-thioxopenam Ester through a Hydroxy Group Directed Chlorinolysis

Hydroxy group directed chlorinolysis of (3S,4R)-3--4-ethylthioazetidin-2-one (4) gives predominantly the corresponding (4S)-4-chloroazetidinone (5) which is cyclised to the (5R,6S)-6--2-thioxopenam (1).

AN EFFICIENT SYNTHESIS OF 2-SUBSTITUTED-THIO-6-HYDROXYETHYL-PENEM-3-CARBOXYLIC ACIDS VIA 2-THIOXOPENAMS

Allyl and p-nitrobenzyl (5R,6S)-6-((R)-1-(t-butyldimethylsilyloxy)ethyl)-2-thioxopenam-3-carboxylates (19) were synthesized by base mediated cyclization of the corresponding 1-carboxylmethyl-4-phenoxy(thiocarbonyl)thio-2-azetidinones (16).The thioxopenams underwent alkylation and Michael reactions to produce 2-alkylthio- and 2-alkenylthio-penem derivatives 20 and 21.

2-Thioxopenams, Useful Intermediates for Penem Synthesis

The new penam derivatives, 2-thioxopenams, are prepared by a novel synthetic method and treated with alkylating agents to give penem derivatives.