Patent ID: 8008289

Claim:
A compound of formula (I) wherein: y is any integer from 1 to 8; z is any integer from 1 to 8 with the proviso that y and z cannot simultaneously be 1; X is —CO—(Y) k —(R 1 ) n or SO 2 —(Y) k —(R 1 ) n ; k is 0 or 1; Y is a cycloalkyl, polycyloalkyl, cycloalkenyl or polycycloalkenyl group; each R 1 is independently selected from an alkylaminoalkyl, alkylaminodialkyl, charged alkylaminotrialkyl or charged alkylcarboxylate radical of 1 to 20 carbon atoms; or each R 1 is independently selected from charged aminotrialkyl, or carboxylate radical; and n is any integer from 1 to m, where m is the maximum number of substitutions permissible on the cyclo-group Y; and, where R 1 is charged, one or more suitable counter-ions are present.