Stereoselective reductive amination of β-keto esters derived from dipeptides. Stereochemical and mechanistic studies on the formation of 5-carboxymethyl-2-oxopiperazine derivatives

✍ Scribed by Rosario Patiño-Molina; Rosario Herranz; Ma Teresa García-López; Rosario González-Muñiz

• Publisher: Elsevier Science
• Year: 1999
• Tongue: French
• Weight: 804 KB
• Volume: 55
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(99)00957-6

✦ Synopsis

The stereoselective generation of 3,%disubstituted and 3.5.6~trisubstituted 2-oxopiperazine derivatives can be accomplished by intramolecular reductive amination of P-keto esters derived from Z-Xaa-Gly-OH and Z-Xaa-Yaa-OH dipeptides, respectively. Differences in the stereoselectivity between the use of NaBHqCN and hydroaen as reducing agents are due to the reduction of different intermediates, as deduced from experimenis of isotopie labelling with deuterium.