Patent ID: 8741259

Claim:
A compound having formula I: or a pharmaceutically acceptable salt thereof, wherein: R 1 -R 4 are each independently H, hydroxyl, alkyl, alkoxy, aminocarbonyl, or halogen; R 5 is H, alkyl, aralkyl, or aminocarbonyl; A represents —N═C(R 15 )— (wherein a bond at the left end bonds to the benzene ring of formula I above and a bond at the right end bonds to the nitrogen heteroatom of formula I above) or —NH—CH(R 15 )— (wherein a bond at the left end bonds to the benzene ring of formula I above and a bond at the right end bonds to the nitrogen heteroatom of formula I above); R 15 is represented by formula II: wherein: R 6 -R 9 are each independently H, hydroxyl, alkyl, or alkoxy; R 10 -R 14 are each independently H, hydroxyl, alkyl, alkoxy, or aminocarbonyl; and X is O, S or N(H); with the proviso that the compound of formula I is not