2-Amino-quinolin-4-one-3-phosphonic acid esters

A compound of the formula:

• ##STR7## wherein R.sup.O is hydrogen, alkyl of 1 to 6 carbon atoms, alkenyl of 3 to 6 carbon atoms, alkynyl of 3 to 6 carbon atoms, cycloalkyl of 3 to 6 carbon atoms, cycloalkylalkyl in which the cycloalkyl is of 3 to 6 carbon atoms and the alkyl portion is of 1 or 2 carbon atoms, or ##STR8## n is 0 or 1, Y and Y' are independently hydrogen, fluoro, chloro, or bromo, alkyl of 1 to 3 carbon atoms, alkoxy of 1 to 3 carbon atoms or trifluoromethyl,
• R and R' are independently hydrogen, fluoro, chloro, bromo, alkyl of 1 to 4 carbon atoms, alkoxy of 1 to 4 carbon atoms, nitro or trifluoromethyl, with the proviso that only one of R and R' can be from the group consisting of nitro and trifluoromethyl, or R and R'
• together form 6,7-methylenedioxy, and R.sub.1 and R.sub.2 are independently alkyl of 1 to 4 carbon atoms, with the further proviso that the unsaturation in any alkenyl or alkynyl is on other than the alpha carbon atom.