| 摘要 |
There are provided chelating agents particularly useful for the preparation of diagnostic and therapeutic agents for magnetic resonance imaging, scintigraphy, ultrasound imaging, radiotherapy and heavy metal detoxification, said agents being compounds of formula I X-CHR1-NZ-(CHR1)n-A-(CHR1)m-NZ-CHR1-X (I) (wherein each of the groups Z is a group -CHR1X or the groups Z together are a group -(CHR1)q-A min -(CHR1)r-, where A min is an oxygen or sulphur atom or a group -N-Y; A is a group -N-Y or A-(CHR1)m- represents a carbon-nitrogen bond or, when the groups Z together are a group -(CHR1)q-A min -(CHR1)r-, A may also represent an oxygen or sulphur atom; each Y, which may be the same or different, is a group -(CHR1)p-N(CHR1X)2 or a group -CHR1X; each X, which may be the same or different, is a carboxyl group or a derivative thereof or a group R1; each R1, which may be the same or different, is a hydrogen atom, a hydroxyalkyl group or an optionally hydroxylated alkoxy or alkoxyalkyl group; n,m,p,q and r are each 2,3 or 4; with the provisos that at least two nitrogens carry a -CHR1X moiety wherein X is a carboxyl group or a derivative thereof, that each -CHR1X moiety is other than a methyl group, and that unless A min is sulphur or A is N-(CHR1)p-N(CHR1X)2 at least one R1 is other than hydrogen and that where A and A min are groups NCHR1X at least one CHR1X group is other than a CH2X<3> group (wherein X<3> represents a caboxyl group or a derivative thereof or a 2-hydroxyethyl or 2,3-dihydroxypropyl group)) and salts thereof. |
