Abstract A series of benzimidazole, thiazole, and benzothiazole carbamates derived from 8-methyl-8-azabicyclo[3.2.1]octan-3α-ol hydrochloride was synthesized and studied by 1 H, 13 C NMR and IR spectroscopy. To assist in the interpretation of the spectroscopic data, the free bases were obtained and studied by IR spectroscopy in different media. As in related compounds, spectroscopic results showed that two different carbamates (1-carbamate or 2-carbamate) could be obtained in the case of the hydrochlorides of benzimidazole derivatives. The hydrochlorides studied displayed in DMSO- d 6 solution a preferred flattened chair-envelope conformation with the N CH 3 substituent in an equatorial disposition. Pharmacological assays in vitro and in vivo were drawn to evaluate 5-HT 3 activity.