Patent ID: 6916831

Claim:
A compound having a structure according to Formula I: wherein: X is selected from the group consisting of O and S; Y is selected from the group consisting of O and S; m is from 1 to 3; n is from 1 to 5; R 1 and R 3 are each independently selected from the group consisting of H, hydroxy, lower alkyl, lower alkoxy, halo, amino, aminoalkyl, nitro, heteroaryl, —OC(═O)R 6 , —O(C═O)OR 6 ; and —O(C═O)N(R 6 ) 2 ; subject to the proviso that at least one of R 1 and R 3 is not H; R 2 is selected from the group consisting of: where p is O to 4, R 5 is hydroxy, alkoxy or amino, and R 6 is H or lower alkyl; or a pharmaceutically acceptable salt thereof.