Benzoxazole, benzothiazole and benzimidazole derivatives as fungicides

A compound having the general formula (I):

• and stereoisomers thereof, in which A, B, C and D are independently H, halo, C.sub.1-4 alkyl, C.sub.2-4 alkenyl, C.sub.2-4 alkynyl, C.sub.1-4 alkoxy, C.sub.1-4 alkylthio, cyano, nitro, C.sub.1-4 haloalkyl, phenyl, phenoxy, benzyl or benzyloxy, the phenyl moieties of any of the foregoing being optionally substituted with one or more of halo, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, nitro or cyano;
• X is oxygen, sulphur or NR, in which R is H or C.sub.1-4 alkyl;
• and W is CH.sub.3 CH.dbd.C.CO.sub.2 CH.sub.3 or CH.sub.3 O.N.dbd.C.CONR.sup.1 R.sup.2, in which R.sup.1 and R.sup.2 are independently H or methyl.