Abstract Eight new imidazo [2, 1-b] thiazoles were synthesized in order to evaluate their ability to stimulate the proliferation of thymic lymphocytes. The 2-chloro (5–8) proved more active than the 2, 3-dimethyl derivatives (1–4): in particular compounds 6 and 7 were more active than levamisole.
![2-chloro-6-(4-methylphenyl)imidazo[2,1-b][1,3]thiazole Structure](https://image.chemsrc.com/caspic/206/135718-54-6.png)