The Action on Tyrosine and on Phxnylamino- Acetic Acid of Acetic Anhydride and Acetone in the Presence of Pyridine
نویسندگان
چکیده
There are recorded in literature several instances in which the acylation of amino acids in the presence of pyridine proceeded abnormally. ’ We have encountered an unexpected reaction in attempting to acetylate I-tyrosine suspended in. a solution of pyridine in commercial acetic anhydride (containing 90 to 95 per cent of the pure anhydride). From the reaction product a orystalline substance, CMH~~O~N, melting at 122-123”C., was isolated. This compound contains at least one acetyl group (attached to the tyrosine hydroxyl) which is easily removed on boiling for a short time with 1 equivalent of 0.66 N sodium hydroxide. A compound, G2H1603N, is thus obtained. On the basis of these preliminary results, the two possible structures I and II were considered for the compound CIJIi~O~N.
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