Compounds of the formula ##STR1## wherein R.sup.1 and R.sup.3 each is hydrogen or R.sup.1 and R.sup.3 together form a second carbon-to-nitrogen bond, R.sup.2 is hydrogen or cyano, R.sup.4 is alkyl and Ar is one of certain aromatic moieties. The compounds can be used as abscission agents for the loosening of fruit and/or leaves on plants.
式##STR1##中的化合物,其中R.sup.1和R.sup.3各自是氢或者R.sup.1和R.sup.3共同形成第二个碳-氮键,R.sup.2是氢或
氰基,R.sup.4是烷基,Ar是某些芳香基团中的一个。这些化合物可以用作促进植物果实和/或叶片脱落的脱离剂。