Azlactone of a acetaminocinnamic acid

The azlactone of a-acetaminocinnamic acid may also be prepared by substituting the equivalent amount of glycine for acetylglycine and increasing the amount of atetic anhydride to three molecular proportions, but the yield is only about 45-50 per cent of the theoretical amount. 

The azlactone of a-acetaminocinnamic acid has been prepared by heating a mixture of glycine, benzaldehyde, acetic anhydride, and anhydrous sodium acetate and from iV-chloroacetylphe-nylalanine by treatment with acetic anhydride. ... 

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