Novel N-substituted heterocyclic derivatives represented by the formula, ##STR1## wherein R is hydrogen or lower alkanoyl; R.sub.1 is hydrogen, lower alkyl, lower alkoxy, halogen, nitro, trifluoromethyl, amino or N-lower alkanoylamino; R.sub.2 is hydrogen, halogen, amino or N-lower alkanoylamino; W is oxygen, sulfur, sulfinyl or sulfonyl; and Y is ##STR2## (wherein R.sub.3 is hydrogen, lower alkyl or lower alkanoyl; and R.sub.4 is hydrogen, halogen or lower alkyl), and pharmaceutically acceptable salts thereof, which have excellent anti-inflammatory, analgesic, sedative, anti-convulsive or anti-hypertensive activities.