| abstract |
(57) Abstract: A raw material for a pharmaceutical product such as a cephem compound having excellent antibacterial activity and useful as a therapeutic drug for various bacterial infections is obtained. A compound represented by the following formula (I), that is, a substituted or unsubstituted imidazo [5,1-b] thiazole derivative: (In the formula, R 1 , R 2 , R 3 , and R 4 represent a hydrogen atom, a substituted or unsubstituted alkyl group, a carbamoyl group, or the like.) |