Metal-chelating 2,6-disubstituted pyridine compounds and their use

Abstract

Bifuncitonal chelating pyridine compound and its use for conferring chelating properties on organic compounds. The pyridine compound has the structure ##STR1## where (i) n is an integer 1 or 2, (ii) R.sub.1, R.sub.2 and R.sub.3 represent groups that have no electrons capable of significantly delocalizing or resonating with the pyridine ring, such as hydrogen, alkyl or aralkyl having an aliphatic carbon atom next to the pyridine ring; at least two of R.sub.1, R.sub.2 and R.sub.3 being hydrogen, iii) Z an Z' represent identical or different structures, each of which comprises at least one heteroatom having a free pair of electrons as that the said at least one heteroatom together with the nitrogen atom of the pyridine ring is capable of chelating a metal ion, iv) - - - - specifies that the group X-Y is a substituent replacing a hydrogen anywhere in the parent pyridine compound, and v) X-Y represents an organic group which is inert to said chelation, and in which iX is an inert and stable bridge and Y is a functional group or a residue of an organic compounbd that has properties conferred on the compound of formula II; said group X-Y being linked to the pyridine ring of formula II via an aliphatic carbon atom attached to and acid ester, salt and chelate forms thereof involving at least one of said chelating heteroatoms.