THE PREPARATION OF 2(OR 3)-METHYL-AND 2(OR 3)-PIPERUDINYLTYROSINES

Nor-adrenaline is derived from tyrosine through a series of biochemical reactions, and certain related analogues (Ⅱ,Ⅲ) are potent in the treatment of hypertension. In order to find the compounds which may interfere with the biosynthesis of nor-adrenaline, several tyrosine analogues (Ⅳ,Ⅴ,Ⅵ, and Ⅶ) were synthesized. But none of these compounds are active. The above compounds were prepared by condensation of diethyl 2(or 3)-bromo- methyl-4-acetoxybenzyl-formamidomalonate with excess piperidine and subsequent hydro- lysis of the condensation products (Ⅸ,Ⅹ) and diethyl 2(or 3)-methyl-4-hydroxybenzyl- formamidomalonate with concentrated hydrochloric acid.