80629-51-2

Upstream product

• 75-07-0 acetaldehyde 
• 24138-27-0 methyl-6,6-dibromopenicillanate 
• 24158-88-1 6,6-dibromopenicillanic acid 
• 104862-33-1 (2S,5R,6R)-6-Bromo-6-iodo-3,3-dimethyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]heptane-2-carboxylic acid methyl ester 
• 75-16-1 methylmagnesium bromide 
• 24138-27-0 methyl dibromopenicillanate 

Downstream Products

• 74189-21-2 (2S,6R)-6-((R)-1-Hydroxy-ethyl)-3,3-dimethyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]heptane-2-carboxylic acid methyl ester 
• 85281-73-8 (3S,4R)-3-[(R)-1-(tert-butyldimethylsilyloxy)-ethyl]-4-phenylthio-2-azetidinone 
• 383186-38-7 (3S,4R)-4-benzenesulfonyl-3-((1R)-1-(tert-butyldimethylsilanyloxy)-ethyl)-azetidin-2-one 
• 80629-53-4 {(2S,3R)-2-Ethylsulfanylthiocarbonylsulfanyl-4-oxo-3-[(S)-1-(2,2,2-trichloro-ethoxycarbonyloxy)-ethyl]-azetidin-1-yl}-(triphenyl-λ⁵-phosphanylidene)-acetic acid allyl ester 

Relevant academic research and scientific papers

STEREOSELECTIVITY IN 6-HALOPENICILLANATE GRIGNARD REACTIONS

Structural modifications of 6-halopenicillanate Grignards result in increased "aldol" stereoselectivity.The intermediacy of tetrahedral penicillin carbanions in THF and β-lactam enolates in CH2Cl2/toluene is proposed.

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.

SYNTHESIS OF OPTICALLY ACTIVE PENEMS

A general synthesis for optically active penems is described.Penems undergo a novel thermal isomerisation reaction.