Fungicidal compounds having the formula (I): STR1 and stereoisomers thereof, wherein A is hydrogen, halo, hydroxy, C1-4 alkyl, C1-4 alkoxy, C1-4 haloalkyl, C1-4 haloalkoxy, C1-4 alkylcarbonyl, C1-4 alkoxycarbonyl, phenoxy, nitro or cyano; R1 and R2, which may be the same or different, are hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted heterocyclylalkyl, optionally substituted cycloalkylalkyl, optionally substituted aralkyl, optionally substituted aryloxyalkyl, optionally substituted heterocyclyloxyalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aryl, optionally substituted heterocyclyl, optionally substituted aryloxy, optionally substituted heterocyclyloxy, nitro, halo, cyano, --NR3 R4, --CO2 R3, --CONR3 R4, --COR3, --S(O)n R3 wherein n is 0, 1 or 2, (CH2)m PO(OR3)2 wherein m is 0 or 1, or R1 and R2 join to form a carbocyclic or heterocyclic ring system; R3 and R4, which are the same or different, are hydrogen, optionally substituted alkyl, optionally substituted aralkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted aryl or optionally substituted heteroaryl, or R3 and R4 join to form an optionally substituted heterocyclic ring; and R5 and R6 are independently hydrogen or C1-4 alkyl.