| abstract |
According to the invention there is provided a compound of Formula (I) in which: A is a C 2-8 alkylene group; R 1 , R 2 , R 3 , and R 4 are independently selected from hydrogen, C 1-4 alkyl, C 2-4 dihydroxyalkyl in which the carbon atom attached to the nitrogen atom does not carry a hydroxyl group and no carbon atom is substituted by two hydroxyl groups, or R 2 and R 3 together form a C 2-6 alkylene group which with the nitrogen atom to which R 2 and R 3 are attached forms a heterocyclic ring; X 1 , X 2 and X 3 are independently selected from hydrogen, hydroxyl, NR 1 -A-NR 2 R 3 R 4+ (Z m- ) 1/m , halogeno amino, C 1-4 alkoxy or C 2-8 alkanoyloxy; and (Z m- ) 1/m is an anion of charge m; or a derivative in which the group NR 1 is quaternarised. |