(R)-2-amino-2-(4-hydroxyphenyl)acetamide

D-p-Hydroxyphenylglycinamide is an activated side chain precursor and is an intermediate in the synthesis of 3-(4-Hydroxyphenyl)-2(1H)-pyrazinone (H951260), which is a potential impuritiy of the penicillins, ampicillin and amoxicillin, which have not been reported previously. 3-(4-Hydroxyphenyl)-2(1H)-pyrazinone impurity may be formed during the semi-synthetic preparation of these antibiotics or upon their degradation.