Spectra and fungicidal activities of naphthofuran and naphthopyrone derivatives

For a series of naphthofurans, naphthopyrones and their derivatives, ¹³C NMR, UV and extinction coefficients, FL and quantum yields, as well as agricultural fugicidal activities have been reported. It is found that compounds 2,3-dimethyl-5-hydroxy-furo [3,2-b] naphthalene (I-1),2,7-diacetoxy-1,8-diacetylnaphthalene (III-3),4-methyl-7-hydroxy naphtho [1,2-b] pyran-2-one (II-1) and 3H-4,8,9-trimethyl furo [2',3':5,6] naphtho [1,2-b] pyran-7-one (II-3) have good control activities to colletotrichum in vitro, and the first two have good control activities to the colletotrichum in vivo.