Synthesis and in vitro antifungal activity of 1-amino-3,4-dialkylnaphthalene-2-carbonitriles and their analogues

Twenty-four 3- and/or 4-alkyl-substituted 1-aminonaphthalene-2-carbonitrile s and their analogues were prepared and evaluated for growth-inhibiting act ivity against four phytopathogenic fungi: Fusarium culmorum, Alternaria bra ssicicola, Botrytis cinerea and penicillium expansum. The results obtained were compared with the activity of a commercial fungicide. The highest fung istatic activity was revealed by amino nitriles having hydrogen atoms or on ly one short alkyl group (CH3, C2H5) at the 3- or 4-position of the naphtha lene system. The minimum values of calculated EC50 and EC95 indexes were 1. 1 and 5.1mg litre(-1), respectively. These values were considerably lower t han those for the reference fungicide. (C) 2001 Society of Chemical Industry.