The present invention provides a polychelant compound of formula (VII), (wherein each X which may be the same or different is NZ, O or S, at least two Xs being NZ; B is (CR.sup.1 Y) or --N(CR.sup.1.sub.2 Y)--; each Z is a group R.sup.1 or a group CR.sup.1.sub.2 Y, at least one Z being a group CR.sup.1.sub.2 Y; each Y is a group CO.sub.2 H, PO.sub.3 H, SO.sub.3 H, CONR.sup.1.sub.2, CON(OR.sup.1)R.sup.1, CNS or CONR.sup.1 NR.sup.1.sub.2 ; m is 0 or 1 or 2; each n is 2 or 3; q is 0 or 1 when B is (CR.sup.1 Y) and 2 when B is N(CR.sup.1.sub.2 Y); p is an integer having a value of at least 2; each R.sup.1 which may be the same or different is a hydrogen atom or an alkyl, aryl or aralkyl group optionally substituted by one or more hydroxy or alkoxy groups, or two R.sup.1 groups on ring atoms or in Z groups together represent a linker group L; each L which may be the same or different represents a bond or an organic linker group having a molecular weight of less than 1000 and salts and chelates thereof. These compounds, especially the diand trichelates with paramagnetic or heavy metal ions are especially useful as diagnostic imaging contrast agents.
本发明提供了一种多螯合物化合物,其
化学式为(VII),其中每个X可能相同或不同为NZ,O或S,至少有两个X为NZ; B为(CR.sup.1 Y)或--N(CR.sup.1.sub.2 Y)--; 每个Z为R.sup.1基团或CR.sup.1.sub.2 Y基团,至少有一个Z为CR.sup.1.sub.2 Y基团; 每个Y为CO.sub.2 H,PO.sub.3 H,SO.sub.3 H,CONR.sup.1.sub.2,CON(OR.sup.1)R.sup.1,CNS或CONR.sup.1 NR.sup.1.sub.2基团; m为0或1或2; 每个n为2或3; 当B为(CR.sup.1 Y)时,q为0或1,当B为N(CR.sup.1.sub.2 Y)时,q为2; p为至少为2的整数; 每个R.sup.1可能相同或不同为氢原子或烷基,芳基或芳烷基,可以选择地被一个或多个羟基或烷氧基取代,或者在环原子或Z基团上的两个R.sup.1基团一起表示为连接基L; 每个L可能相同或不同,表示键或具有分子量小于1000的有机连接基,以及其盐和螯合物。这些化合物,特别是与顺磁性或重
金属离子形成的二和三螯合物,特别适用于诊断成像对比剂。