A therapeutic method comprising treating non-aortal procedural vascular trauma comprising administering to a mammal, subjected to said procedural vascular trauma, an effective cytostatic antiproliferative amount of a compound of formula (I): ##STR5## wherein Z is a covalent bond; Y is H or O(C1 -C4)alkyl, R1 and R2 are individually (C1 -C4)alkyl or together with N are a saturated heterocyclic grou