N-aralkyl- and N-heteroaralkyl-aminoalkanephosphinic acids

A N-aralkyl-aminoalkanephosphinic acid of formula I ##STR16## wherein R is lower alkyl having at least 2 carbon atoms, lower alkenyl, lower alkynyl, oxo-lower alkyl, hydroxy- or dihydroxy-lower alkyl, hydroxy-lower alkenyl, mono-, di- or poly-halo-lower alkyl, mono-, di- or poly-halo-lower alkenyl, mono-, di- or poly-halo(hydroxy)-lower alkyl, mono-, di- or poly-halo(hydroxy)-lower alkenyl, lower alkoxy-lower alkyl, di-lower alkoxy-lower alkyl, lower alkoxy(hydroxy)-lower alkyl, lower alkoxy(halo)-lower alkyl, lower alkylthio-lower alkyl, di-lower alkylthio-lower alkyl, cycloalkyl, hydroxycycloalkyl, oxa-, dioxa-, thia- and dithia-cycloalkyl, cycloalkyl-lower alkyl, cycloalkenyl-lower alkyl, cycloalkyl(hydroxy)-lower alkyl, (lower alkyl thio)cycloalkyl(hydroxy)-lower alkyl, or mono- or di-phenyl-lower alkyl that is unsubstituted or mono-, di- or tri-substituted by lower alkyl, lower alkoxy, halogen, hydroxy and/or by trifluoromethyl, naphthyl-lower alkyl, R.sub.1 is hydrogen or hydroxy, R.sub.2 is a phenyl-lower alkyl radical that is mono- or di-substituted by carboxy;

• lower alkoxycarbonyl;
• cyano;
• carbmoyl;
• N-mono- or N,N-di-lower alkylcarbamoyl;
• carboxy-lower alkyl;
• lower alkoxycarbonyl-lower alkyl;
• cyano-lower alkyl;
• carbamoyl-lower alkyl;
• N-mono- or N,N-di-lower alkylcarbamoyl-lower alkyl;
• and R.sub.3 is hydrogen, lower alkyl or R.sub.2, or a salt thereof.