The present invention provides wherein R1 is selected from the group consisting of C1-C10 alkoxy, OH and NR4R5; R2 is selected from the group consisting of C1-C10 alkyl and (CH2)nOH; R3 is selected from the group consisting of C1-C10 alkyl, heteroaryl, e.g. thienyl, furanyl and pyridyl, phenyl, mono, -di-, tri-substituted phenyl and heteroaryl; R4 and R5 are independently selected from the group consisting of H, C1-C10 alkyl, C1-C10 alkyl hydroxyl; m is 0 or an integer from 1 to 3 and n is an integer of from 1 to 4. These compounds are useful in lowering intraocular pressure and/or treating glaucoma or providing neuroprotection to the eye of a human patient.