Abstract: An intimal thickening inhibitory agent comprising, as an active ingredient, a compound represented by formula (1): wherein x represents an oxygen atom or a group of formula (2) —S—(O)n  (2) wherein n represents an integer of from 0 to 2, R1 represents a hydrogen atom or an acyl group; R2 represents a hydrogen atom, a lower alkyl group or a lower alkenyl group; R3 represents a lower alkyl group; and R4, R5, and R6, which may be the same or different, each represent a hydrogen atom or a substituted or unsubstituted alkyl group; or R3 and R4 may be taken together to form a 5-membered ring; or R5 and R6 may be taken together to form a cycloalkyl group; provided that R6 is nil when R3 and R4 are taken together to form benzofuran or benzo[b]thiophene.

Abstract: An intimal thickening inhibitory agent comprising, as an active ingredient, a compound represented by formula (1): ##STR1## wherein X represents an oxygen atom or a group of formula (2): ##STR2## wherein n represents an integer of from 0 to 2, R.sub.1 represents a hydrogen atom or an acyl group; R.sub.2 represents a hydrogen atom, a lower alkyl group or a lower alkenyl group; R.sub.3 represents a lower alkyl group; and R.sub.4, R.sub.5, and R.sub.6, which may be the same or different, each represent a hydrogen atom or a substituted or unsubstituted alkyl group; or R.sub.3 and R.sub.4 may be taken together to form a 5-membered ring; or R.sub.5 and R.sub.6 may be taken together to form a cycloalkyl group; provided that R.sub.6 is nil when R.sub.3 and R.sub.4 are taken together to form benzofuran or benzo[b]thiophene.