The cyclic voltammetric response of dimethyl-[1-butyl-2,4-dioxo(1H,3H)pyrimido]tetrathiafulvalene 1 is studied in the presence of aminopyridine derivatives. The first oxidation potential of 1 increases with an increase in 2,6-di(N-acetylamino)pyridine concentration. with the maximum shift being 30 mV. This is assigned to the formation of a multihydrogen-bond complex in the neutral state with the binding constant estimated to be ca. 1000 M-1. An irreversible following chemical reaction is suggested for the explanation of the complicated behaviour of the second redox wave of 1 in the presence of 2,6-di(N-acetylamino)pyridine.