The present disclosure describes compounds of the following formula in which: the groups A, which may be identical or different, represent a group n is an integer equal to 1 or 2, Y represents an oxygen or sulfur atom, a methylene, hydroxymethylene, carbonyl or thiocarbonyl group, or a group of formula the groups R, which may be identical or different, represent a hydrogen, an alkyl, alkylamine, hydroxyl-alkyl or alkyloxy chain containing from 1 to 6 carbons, or a &mdash；COOH, &mdash；CONH2, &mdash；COOR2 or &mdash；CONHR2 group in which R2 is an alkyl chain containing from 1 to 6 carbons, or, when the substituents R are identical in the 2-pyridinyl groups, the substituents R2 may together form an ethereal cyclic alkyl chain, with the exception of the compounds: 2,6-di[5-(2-pyridyl)pyrrol-2-yl]pyridine and bis[5-(6-methyl-2-pyridyl)pyrrol-2-yl]methane.
