Patent ID: 8795706

Claim:
A method of treating presbyopia comprising administering to a subject a compound having the structure of Formula I or a pharmaceutically acceptable salt thereof: wherein at least one of X and Y is sulfur, and the other is sulfur, selenium, or a sulfonic group; R 19 is substituted or unsubstituted alkylene; R 20 , R 21 , R 30 , and R 31 are each independently hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted heterocycloalkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl; wherein R 30 and R 31 may optionally be joined together or together form a single bond; Z is N or O; and m is 0 or 1, wherein if Z is O, then m is 0, and if Z is N, then m is 1, and wherein the compound is not 5-(1,2-dithiolan-3-yl)pentanoic acid.