sodium(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-(2,2-Dimethyl-1-propyloxycarbonyloxy)ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-(2-Ethylphenoxycarbonyloxy)ethyl(1S,5R,6s)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-(2-Methylbenzoyloxy)ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthio-imidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

Cyclohexyl(cyclohexyloxycarbonyloxy)methyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

Cyclohexylcarbonyloxymethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-(3,3-Dimethyl-1-butyloxycarbonyloxy)ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-((Indan-5-yl)oxycarbonyloxy)ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-(4-Methylphenoxycarbonyloxy)ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

2,5-Dimethylbenzoyloxymethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthio-imidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-[2-(1-Propyl)phenoxycarbonyloxy]ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

4-(N,N-di-n-propylaminosulfonyl)benzoyl-oxymethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-(4-Methyl-1-pentyloxycarbonyloxy)ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-(Phenoxycarbonyloxy)ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthio-imidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

2-Adamantyloxycarbonyloxymethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthio-imidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-[2-(2-Propyl)phenoxycarbonyloxy]ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate

1-(2,4,6-Trimethylphenoxycarbonyloxy)ethyl(1S,5R,6S)-6-((1R)-1-hydroxyethyl)-1-methyl-2-(7-methylthioimidazo[5,1-b]thiazol-2-yl)-1-carbapen-2-em-3-carboxylate