Mixed carboxylic‐carbonic acid anhydrides of acylamino acids and peptides as a convenient source of 2,4‐dialkyl‐5(4 H)‐oxazolones
Racemic 2‐R 1 ‐4‐R 2 ‐5(4 H )‐oxazolones (R 1 = CH 3 , C 6 H 5 , C 6 H 5 CH 2 OCONHCH 2 R 2 = aliphatic and C 6 H 5 CH 2 ) have been prepared in good yields by reaction of the parent N ‐acetyl‐, N ‐benzoyl‐, and N ‐benzyloxycarbonylglycyl‐amino acids with methyl chloroformate in cold dichloromethane...
Published in: | International Journal of Peptide and Protein Research |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
1988
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Subjects: | |
Online Access: | http://dx.doi.org/10.1111/j.1399-3011.1988.tb00042.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1399-3011.1988.tb00042.x https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1399-3011.1988.tb00042.x |
Summary: | Racemic 2‐R 1 ‐4‐R 2 ‐5(4 H )‐oxazolones (R 1 = CH 3 , C 6 H 5 , C 6 H 5 CH 2 OCONHCH 2 R 2 = aliphatic and C 6 H 5 CH 2 ) have been prepared in good yields by reaction of the parent N ‐acetyl‐, N ‐benzoyl‐, and N ‐benzyloxycarbonylglycyl‐amino acids with methyl chloroformate in cold dichloromethane in the presence of N ‐methylmorpholine, followed by washing the mixtures with aqueous solutions and removal of the solvent. The products derived from optically active substrates contained enantiometric excesses of 83–98%. The method cannot be applied to the preparation of oxazolones from N ‐formylamino acids. |
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