The thiosemicarbazone derivatives and their coordination complexes with different 3d- elements posses important biological activity, original analytical applications and other useful physical proprieties. The chemistry of the manganese complexes with this type of ligands is less studied then for other 3d-elements. For the synthesis of manganese polynuclear compounds frequently is used several ligands or a polyfunctional organic assemblies. The polyfunctional organic assemblies can be obtained ussing two technologies: direct condensation of two or more carbonyl with different polyamine and ussing template methodology. In this study we are ussing template reaction on the matrix of manganese(II) salts between salicylaldehyde S-methylthiosemicarbazone and 2-formylpyridine derivatives. In this case the manganese ions is oxidized from 2+ to 3+ with formation of the polynuclear assemblies containing Mn(III). The size of the polynuclear product is directly depending of the substituent in 2-formylpyridine. In the case where we are using non-substituted 2-formylpyridine we have obtained decanuclear assemblies and in the case of 6-substituted 2-formylpyridine with bromo or methyl group the formation of the hexanuclear complexes was observed (Figures 1a and 1b).figureFigure 1. ORTEP representations of the structure of the decanuclear a and hexanuclear b manganese(III) complexes with thiosemicarbazide derivativesIn the structure of manganese(III) polynuclear compounds two different ligand types were found: the initial salicylaldehyde S-methylthiosemicarbazone as deprotonated anion and the addition product of 2-formylpyridine derivatives to the salicylaldehyde S-methylthiosemicarbazone as three charged anion. The ratio of the initial organic components have not influence on the composition of the final product. The complexes show a dominant antiferromagnetic interaction between paramagnetic manganese(III) centers. Acknowledgment: One of the authors (O.P.) thanks the Erasmus Mundus Cooperation Windows Program for the financial support.