130632-19-8

Upstream product

• 17599-61-0 N-benzylidene-1,1,1-trimethylsilanamine 
• 438566-59-7 (3R,4S)-cis-3-benzyloxy-1-[(2R,5R)-2,5-dimethylpyrrolidin-1-yl]-4-phenylazetidin-2-one 
• 100-52-7 benzaldehyde 
• 19810-31-2 Benzyloxyacetyl chloride 
• 438566-45-1 (3R,4S)-3-benzyloxy-1-[(2S)-2-(1-ethyl-1-methoxypropyl)pyrrolidin-1-yl]-4-phenylazetidin-2-one 
• 130632-16-5 Benzyloxy-acetic acid (1R,2S)-2-methylamino-1-phenyl-propyl ester 
• 120419-97-8 (E)-N-benzylidene-1,1,1-trimethylsilanamine 

Downstream Products

• 132127-34-5 (3R,4S)-3-hydroxy-4-phenylazetidin-2-one 
• 136561-53-0 (2R,3S)-2-hydroxy-3-amino-3-phenylpropionic acid 

Relevant academic research and scientific papers

Studies on stereoselective [2+2] cycloadditions between N,N-dialkylhydrazones and ketenes

Staudinger-like cycloadditions between chiral, non-racemic N,N-dialkylhydrazones 1 and functionalized ketenes constitute an efficient methodology for the stereoselective construction of the β-lactam ring. The potential for fine tuning of the dialkylamino

N,N-dialkylhydrazones as the imine component in the Staudinger-like [2+2] cycloaddition to benzyloxyketene

To overcome the limitations of using unstable imines in Staudinger cycloadditions to ketenes, aldehyde N,N-dialkylhydrazones 1 were used as stable imines. This strategy and a fine tuning of the auxiliary result in a straightforward synthesis of cycloadducts 2, deprotected β-lactams 3, and isoserines 4 (see scheme: a) Et3N, toluene, Δ; b) 1. magnesium monoperoxyphthalate, 2. H2, Pd/C; c) H+).

New and efficient approaches to the semisynthesis of taxol and its C-13 side chain analogs by means of β-lactam synthon method

Highly efficient chiral ester enolate-imine condensation giving 3-hydroxy-4-aryl-β-lactams with excellent enantiomeric purity is successfully applied to the asymmetric synthesis of the enantiomerically pure taxol C-13 side chain, N-benzoyl-(2R,3S)-3-phenyl-isoserine and its analogs. (3R,4S)-N-benzoyl-3-(1-ethoxyethoxy)-4-phenyl-2-azetidinone readily derived from the 3-hydroxy-4-phenyl-β-lactam is coupled with protected baccatin IIIs, followed by deprotection to give optically pure taxol and 10-deacetyl-7,10-bis(Troc)-taxol in good yields. Fully assigned 1H, 13C, and 2D (COSY and HETCOR) NMR spectra of taxol thus synthesized are shown and discussed.

ASYMMETRIC SYNTHESIS OF β-LACTAMS BY CHIRAL ESTER ENOLATE-IMINE CONDENSATION

Asymmetric cyclocondensation of N,N-bis(silyl)glycinates bearing chiral ester moieties with aldimines is found to proceed with extremely high enantioselectivity to give the corresponding chiral β-lactams in good to high yields.It is found that the E/Z-geometry of the chiral ester-enolate is responsible for cis/trans stereochemistry of the β-lactam formed.Effects of various chiral auxiliaries in the ester-enolates on the enantioselectivity of the reactions are examined.