Chelating agents and their metal chelates for treating free radical induced conditions

Abstract

The invention provides the use of a compound of formula (I) or a metal chelate or salt thereof in the manufacture of a therapeutic agent for use in the treatment of prophylaxis of conditions resulting from the presence of free radicals in the human or non-human animal body (wherein in formula (I): each R,independently represents hydrogen or —CH,COR,; R,represents hydroxy, optionally hydroxylated alkoxy, amino or alkylamido; each R,independently represents a group XYR,; X represents a bond, or a C,alkylene or oxoalkylene group optionally substituted by a group R,; Y represents a bond, an oxygen atom or a group NR,; R,is a hydrogen atom, a group COOR,, an alkyl, alkenyl, cycloalkyl, aryl or aralkyl group optionally substituted by one or more groups selected from COOR,, CONR,, NR,, OR,, ═NR,, ═O, OP(O)(OR,)R,and OSO,M; R,is hydroxy, an optionally hydroxylated, optionally alkoxylated alkyl or aminoalkyl group; R,is a hydrogen atom or an optionally hydroxylated, optionally alkoxylated alkyl group; M is a hydrogen atom or one equivalent of a physiologically tolerable cation; R,represents a C,alkylene group, a 1,2-cycloalkylene group, or a 1,2-arylene group; and each R,independently represents hydrogen or C,alkyl). Such compounds are particularly effective in relieving symptoms associated with reperfusion of ischemic tissue and in treating or preventing radiation-induced injury.