| 摘要 |
This is an improved process of manufacturing N-acyl derivatives of glycines alpha -substituted by radicals with an aromatic nature by condensation of the addition product of glyoxylic acid and an amide, with an aromatic compound. In a first stage, the reaction is carried out at low temperature, in a concentrated sulfuric medium, of an aliphatic nitrile of the formula R-C 3BOND N in which R is a radical selected from the group of substituted and unsubstituted, saturated and unsaturated alkyl radicals, with a concentrated aqueous solution of glyoxylic acid. Then in a second stage, the mixture obtained is condensed also at low temperature with a compound of aromatic nature not including a hydroxyl group and having at least one substitutable free hydrogen, and the resulting product is collected. The concentrated sulfuric acid may be supplemented with acetic acid during the second stage. A surface active agent may be also added in this stage. The products are valuable intermediates for the preparation of semi-synthetic penicillins.
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