ORGN 173 |
| The formation of 2,5-diketopiperazines from a water suspension of N-Boc protected dipeptide alkylesters was induced by microwave assisted heating. The products, which precipitated, were obtained in good yields and required no further purification. However, racemisation or diastereomer formation was found with one or two phenylalanines in the sequence. Microwave assisted heating was likewise applied in the Boc deprotecting step as well as in the synthesis of the protected dipeptides, where polystyrene bound carbodiimide, with HOBt as additive, was used as coupling agent. Two side products, formed through alkylation of HOBt by the solvent dichloromethane at the enhanced temperature, were detected during the peptide coupling. |
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Physical Organic Chemistry, Combinatorial and Process Chemistry, New Reactions and Methodology, Peptides, Proteins and Amino Acids
8:00 PM-10:00 PM, Sunday, April 6, 2008 Morial Convention Center -- Hall A, Poster
Division of Organic Chemistry |