Benzofuran and dihydrobenzofuran melatonergic agents

A compound of Formula I or a pharmaceutically acceptable solvate thereof having the Formula:

• ##STR28## wherein Q.sup.1 and Q.sup.2 each are independently hydrogen or halogen;
• Y is CR.sup.3, CR.sup.3 R.sup.4 or (CH.sub.2).sub.n, with n=1;
• Z is oxygen and X is CH.sub.2 or CH;
• or X is oxygen and Z is CH.sub.2 or CH;
• R is hydrogen, halogen or C.sub.1-4 alkyl in both cases;
• m is 1 or 2;
• R.sup.1 is C.sub.1-6 alkyl, C.sub.3-6 cycloalkyl, C.sub.1-3 haloalkyl, C.sub.1-6 alkylamino, C.sub.2-6 alkenyl, C.sub.1-4 alkoxy(C.sub.1-4)alkyl, C.sub.1-4 alkylthio(C.sub.1-4)alkyl or C.sub.1-4 trifluoromethylalkyl;
• R.sup.2 is hydrogen or C.sub.1-4 alkyl;
• and
• R.sup.3 and R.sup.4 each are independently hydrogen or C.sub.1-4 alkyl.