436156-75-1

Upstream product

• 436156-44-4 tert-butyl N-(3,4,5-trimethoxy)benzyl-L-phenylalaninate 
• 15100-75-1 L-phenylalanine tert-butyl ester hydrochloride 
• 86-81-7 3,4,5-trimethoxy-benzaldehyde 
• 436156-61-5 tert-butyl N-(3,4,5-trimethoxy)benzyl-N-chloroacetyl-L-phenylalaninate 

Downstream Products

• 344765-43-1 4-benzyl-4-tert-butoxycarbonyl-2-azetidinone 

Relevant academic research and scientific papers

Amino acid-derived 4-alkyl-4-carboxy-2-azetidinones. New insights into β-lactam ring formation and n-deprotection

The preparation and N-deprotection of a series of phenylalanine-derived 2-azetidinones incorporating 2,4-dimethoxybenzyl (Dmb), 2,3,4-, 2,4,6- and 3,4,5-trimethoxybenzyl (Tmb) groups at 1 position are described. The base-promoted cyclization of the corresponding methoxy-substituted Nαbenzyl-Nα-chloroacetyl derivatives to the 1,4,4-trisubstituted azetidinones proceeded with moderate to good yields, except for the 2,4,6-Tmb analogue. In spite of the number and position of the OMe groups, N-unsubstituted β-lactams were obtained by oxidative debenzylation using potassium peroxodisulfate. Alternatively, debenzylation of Pmb, Dmb and Tmb 2-azetidinones with TFA/anisole resulted in concomitant β-lactam opening to α-benzylaspartic acid derivatives.