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Tetra-2-pyridinylpyrazine (TPP) or 2,3,5,6-tetra-2-pyridinylpyrazine (tppz) is a poly-N-donor ligand
P 4861 (OTTO) Tetra-2-pyridinylpyrazine, 97% Cas 25005-97-4 - used as reagent in chemical research.