In order to develop potent analgesic/anti-inflammatory compounds with reduced ulcerogenic risk, a series of thiazolotriazolyl-carboxylic and acetic acid esters were synthesized and characterized by spectral and elementary analysis. All synthesized compounds were screened for in vivo anti-inflammatory activities in mice by carregeenan-induced paw edema model. The compounds showing 20% reduction in paw edema were also evaluated for their analgesic activities by acetic acid-induced writhing test and the gastric ulceration risk by determining the lipid peroxidation level in stomachs. Among the compounds tested, compounds 1, 4, 6, 7, 8, 1a, 2a, 3a, 4a, 7a, 2b, and 8b showed moderate-to-good anti-inflammatory activity at various doses in any of the measurement intervals. Compounds 7a, 2b, and 8b were the most actives of the series in analgesic activity test. Moreover, compounds 1, 4, and 8 were found to be safe in stomach in respect of free radical production.