Ophthalmically acceptable compositions used in arresting the development of cataracts or macular degeneration comprising a pharmaceutically acceptable carrier or diluent and a compound having the formula: ##STR00001## where R.sub.1 and R.sub.2 are, independently, H or C.sub.1 to C.sub.3 alkyl; R.sub.3 and R.sub.4 are, independently C.sub.1 to C.sub.3 alkyl; and where R.sub.1 and R.sub.2, taken together, or R.sub.3 and R.sub.4, taken together, or both may be cycloalkyl; R.sub.5 is H, OH, or C.sub.1 to C.sub.6 alkyl; R.sub.6 is or C.sub.1 to C.sub.6 alkyl, alkenyl, alkynyl, or substituted alkyl or alkenyl; R.sub.7 is C.sub.1 to C.sub.6 alkyl, alkenyl, alkynyl, or substituted alkyl or alkenyl or where R.sub.6 and R.sub.7, or R.sub.5, R.sub.6 and R.sub.7, taken together, form a carbocycle or heterocycle having from 3 to 7 atoms in the ring.