Compounds of the formula: ##STR1## wherein R is aryl of 6 to 12 carbon atoms or aralkyl of 7 to 14 carbon atoms either optionally substituted with 1 to 3 substituents independently selected from lower alkyl of 1 to 6 carbon atoms, lower alkoxy of 1 to 6 carbon atoms, lower alkylthio of 1 to 6 carbon atoms, lower alkylsulfinyl of 1 to 6 carbon atoms, lower alkylsulfonyl of 1 to 6 carbon atoms, halogen, trihalomethyl, nitro, cyano or carboxyl; alkyl of 1 to 10 carbon atoms, cycloalkyl of 3 to 10 carbon atoms, lower alkenyl of 2 to 6 carbon atoms, or lower alkynyl of 2 to 6 carbon atoms, all optionally substituted with 1 to 3 halogen atoms; lower alkoxyalkylene; lower alkylene carbalkoxy; lower alkylthioalkylene; lower alkylsulfinylalkylene; or lower alkylsulfonylalkylene; R.sup.1 and R.sup.2 are independently hydrogen, lower alkyl of 1 to 6 carbon atoms, aryl of 6 to 12 carbon atoms, or thienyl, or taken together form an alkylene bridge to give a cycloalkyl group of 3 to 10 carbon atoms; and R.sup.3 is alkyl of 1 to 3 carbon atoms substituted with 3 to 6 halogen atoms or trihalovinyl are fungicidal.