The present invention relates to 1,3,4-oxadiazole heterocyclic carbon compounds and to their preparation and use. More particularly. the invention relates to 1,3,4-oxadiazoles substituted in the 2-position with 3-chlorophenylpiperazinylalkyl moieties and their therapeutic use in treating depression.
3-chlorophenylpiperazinylalkyl derivatives of certain heterocycles have been previously disclosed as having psychotropic activity and specifically being of use in the treatment of depression. These art compounds, as well as those of the present invention, can be represented structurally as depicted below. ##STR1## In this structure Het denotes certain heterocyclic moieties and it is the nature of these that distinguishes the art compounds from those of the instant invention as well as from each other. Temple and Lobeck in U.S. Pat. No. 4,487,773 disclose and claim a series of compounds (1) depicted structurally below. ##STR2## wherein R is halogen or alkoxy; n is 2-4: and R.sup.1 is hydrogen, halogen or alkoxy. These compounds have antidepressant activity.
U.S. Pat. No. 3,857,845 to G. Palazzo describes the antidepressant compound (2) commonly called etoperidone. The structure for etoperidone is depicted below. ##STR3##
U.S. 3,381,009 to G. Palazzo, et al., discloses a related series of 1,2.4-triazolo [4.3-a] pyridines of which one compound, commonly known as trazodone, is an effective antidepressent in man. The structure for trazodone (3) is shown below. ##STR4##
Temple and Yeager in U.S. Pat. No. 4,367,335 and U.S. Pat. No. 4,456,756 disclose and claim a series of compounds (4) with psychotropic properties whose structure is depicted below. ##STR5## wherein R.sup.1 is, inter alia, halogen.
None of the aforementioned references disclose or suggest piperazine derivatives containing the 1,3,4-oxadiazole heterocyclic component of the subject compounds of this invention.