The present application describes compounds of general formula I where R1 is selected from any one of pyridinyl, thienyl, furanyl, imidazolyl, and triazolyl; and where each R1 heteroaromatic ring may optionally and independently be further substituted by 1, 2 or 3 substituents selected from straight and branched C1-C6 alkyl, NO2, CF3, C1-C6 alkoxy, chloro, fluoro, bromo, and iodo. The substitutions on the heteroaromatic ring may take place in any position on the ring system. The invention also includes enantiomers, salts and pharmaceutical compositions containing the compounds. The compounds may be used in treating patients for pain.