methyl 2-keto-2-(thieno[2,3-b]thiophen-2-yl)thioacetate

[(E)-Methoxyimino]-thieno[2,3-b]thiophen-2-yl-acetyl chloride

[(Z)-Methoxyimino]-thieno[2,3-b]thiophen-2-yl-acetic acid

(6R,7R)-7-{2-[(Z)-Methoxyimino]-2-thieno[2,3-b]thiophen-2-yl-acetylamino}-3-methyl-8-oxo-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid

(6R,7R)-7-((S)-2-Amino-2-thieno[2,3-b]thiophen-2-yl-acetylamino)-3-methyl-8-oxo-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid