abstract |
There is provided a compound of formula R 1 -CO-X-Y-Z-R 2 wherein X and Z are each optional groups independently selected from saturated or unsaturated carbon chains having a length of 1 to 3 carbons; Y is SO, S, SO 2 , CH=CH, CH 2 CH 2 or O; R 1 is selected from the following groups (A) wherein - - - denotes the point of attachment; R 2 is a heteroaryl group comprising an optionally substituted 5 or 6 membered ring, which ring contains only carbon and at least one nitrogen, or contains only carbon, and at least two nitrogens and at least one sulphur; and wherein (i) when R 1 is group (B) and -CO-X-Y-Z- is CO-CH 2 -SO, CO-CH 2 -S, or CO-CH 2 -SO 2 , R 2 is other than group (C) and; (ii) when R 1 is group (D) and -CO-X-Y-Z- is -CO-CH 2 -O-, R 2 is other than group (E). |