| abstract |
A heterocyclic compound represented by the general formula (1) or a salt thereof: n n n n n n n n n n wherein m, l, and n respectively represent an integer of 1 or 2; X represents βOβ or βCH 2 β; n R 1 represents hydrogen, a lower alkyl group, a hydroxy-lower alkyl group, a protecting group, or a tri-lower alkylsilyloxy-lower alkyl group; n R 2 and R 3 , which are the same or different, each independently represent hydrogen or a lower alkyl group; or R 2 and R 3 are bonded to form a cyclo-C3-C8 alkyl group; and n R 4 represents an aromatic group or a heterocyclic group, wherein n the aromatic or heterocyclic group may have one or more arbitrary substituent(s). |