Studies with tetrazole derivatives; some pharmacologic properties of 1,5-disubstituted tetrazoles.

The action of a group of 1,5-disubstituted tetrazole derivatives on the central nervous system has been studied. Both stimulatory and depressant effects have been observed. Certain relationships between chemical structure and pharmacologic action have become apparent. The optimum structural factors for maximum stimulatory action appear to be the presence of a relatively large saturated cyclic or open chain aliphatic group in position 1 and a small group, preferably methyl, in the 5 position of the tetrazole ring system. Several compounds in the group, namely 1-cyclohexyl-5-methyl tetrazole (TT-79), 1-cyclohexyl-5-ethyl tetrazole (TT-18), 1-cyclopentyl-5-methyl tetrazole (TT-09) and 1-isobutyl-5-methyl tetrazole (TT-020) are outstanding in their stimulatory effects and deserve further investigation.