| abstract |
A compound that is a compound of formula (I) ** (See formula) ** where -A-B- is -O-CH2-, -S-CH2-, -CH2-O- or -CH2-S-; X is O or NH; R1 and R2 are independently C1-4 alkyl optionally substituted with 1-2 substituents independently selected from hydroxy and C1-4 alkoxy; R3, R4 are independently H, C1-4 alkyl or C3-7 cycloalkyl, each optionally substituted with 1-3 substituents independently selected from halogen, hydroxy, C1-4 alkoxy and C3-7 cycloalkyl; or R3 and R4, together with the nitrogen atom to which they are attached, form a 4- to 6-membered heterocyclic group optionally substituted with 1-3 substituents selected from hydroxy, C1-4 alkyl, C1-4 acyl and C1-4 hydroxyalkyl . R5-R8 are independently H, halogen, hydroxy, C1-4 alkyl or C1-4 alkoxy and R9 is H, hydroxy or C1-4 alkoxy; or a pharmaceutically acceptable salt thereof. |