Patent ID: 7211670

Claim:
A method of synthesizing 3-hydroxyamidino-phenylalanine derivatives of formula (IIa) which are present as: L- or D-enantiomers, (E)- or (Z)-isomers, or (E/Z)-mixtures and as free bases or salts thereof formed with acids, wherein R 1 is: (a) a group of formula wherein R 3 is selected from the group consisting of methoxycarbonyl, ethoxycarbonyl, benzyloxycarbonyl, dimethylaminocarbonyl, acetyl, and propionyl, comprising the reaction of a nitrile of general formula (III) wherein R 1 is as defined above, with hydroxylamine hydrochloride in the presence of sodium carbonate in alcoholic-aqueous solution at reflux temperature.