Method for the treatment and prevention of ocular disorders

A method for treating or preventing an ocular disease

• comprising administering to a subject in need thereof a therapeutically effective amount of a compound of general formula (I):
• wherein:
• Ak is alkylene;
• R1 is —NR5R6, in which R5 and R6 are each independently hydrogen or straight- or branched-chain alkyl comprising from one to six carbon atoms;
• or R5 and R6, together with the nitrogen atom to which they are attached, form a saturated or unsaturated heterocyclic ring containing from four to six ring atoms, which ring may optionally contain another heteroatom selected from the group consisting of nitrogen, oxygen and sulfur and may be optionally substituted by from one to four groups which may be the same or different selected from alkyl, hydroxyl, amino, N-alkylamino and N,N-dialkylamino;
• R2 is isobutyl;
• R3 is (E)-2-butenyl-1 or n-butyl;
• R4 is ethyl, 1-hydroxyethyl, isopropyl or n-propyl;
• or a pharmaceutically acceptable salt or solvate thereof.