Herein disclosed are N-naphthoylglycine derivatives having aldose reductase inhibiting activity. The derivatives are useful for treating diabetic complications. The derivatives are of the formula
(where R' is hydrogen, lower alkyl, lower alkenyl or phenylmethyl, R2 is hydrogen or lower alkyl and R3, R4 and R5 are hydrogen or specified substituents) and therapeutically acceptable salts of the compounds wherein R2 is hydrogen. Certain intermediate amidoacids useful in the preparation of the above mentioned derivatives also have aldose reductive inhibiting effects.
Herein disclosed are N-naphthoylglycine derivatives having aldose reductase inhibiting activity. The derivatives are useful for treating, diabetic complications.