Anthelmintic phosphonamidate and phosphoramidate compositions and methods of use

This invention relates to novel anthelmintic compositions containing as the essential active ingredient, a compound of the formula: wherein R1 is cylcoalkyl, or optionally substituted aralkyl, aryl, pyridyl, or pyrazinyl; R2 is hydrogen, alkyl, cycloalkyl, alkoxyalkyl, alkylthioalkyl, cyanoalkyl, alkenyl, or optionally substituted aralkyl or aryl; R1 and R2 taken together with the nitrogen atom to which they are attached form an optionally substituted morpholino or piperidino group; R3 is hydrogen, alkyl, cycloalkyl, alkenyl, or optionally substituted aralkyl or aryl; R4 is alkoxy, haloalkoxy, dialkylamino, alkylthio, phenoxy or phenylthio; and R5 is alkyl, alkoxy, haloalkoxy, dialkylamino, alkylthio, phenyl, phenoxy or phenylthio; and X is oxygen or sulfur; AND PHARMACEUTICALLY ACCEPTABLE METAL SALTS AND METAL SALT COMPLEXES THEREOF, AND TO METHODS OF EMPLOYING THEM IN THE TREATMENT OF INTESTINAL PARASITES IN ANIMALS, E.G. MAMMALS, FISH, AND BIRDS.