Some new thiazolidines and spirothiazolidines derived from hydrazones of2-methylimidazo[1,2-a]pyridine-3-carboxylic acid hydrazide, a bioisosteric derivative ofisoniazid, were synthesized and characterized by analytical, IR, 1H- and 13C-NMR andmass spectral data. Some of the newly synthesized compounds were screened for theirantimycobacterial activities. None of the tested compounds showed significant in vitroantituberculous activity at 6.25 μg/mL (MIC rifampin 0.031 μg/mL).