| abstract |
The present invention relates to compounds of formula (I) and pharmaceutically acceptable salts of these compounds. In the formula, R6 represents hydrogen or lower alkyl; each R1 represents hydrogen, lower alkyl, halogen, nitro, trihaloalkyl, lower alkoxy, formyl, lower alkanoyl, lower alkylamino or lower dialkylamino; Y represents (II) or (III); X represents O, S or NR5; R2 represents OR7 or NR7R8; each R3 and R4 independently represents hydrogen or lower alkyl; R5, R7 and R8 independently represent hydrogen or lower alkyl; n represents 0-3 and m represents 0-6. These compounds are useful for treating glaucoma or for assessing the function of the cornea in mammals. |