4-Thia-1-azabicyclo(3.2.0)heptane-2-carboxylic acid, 6-((2-amino-2-ethyl-1-oxobutyl)amino)-3,3-dimethyl-7-oxo-, (2S-(2alpha,5alpha,6beta))- 76741-90-7 alpha-Ethyl-alpha-aminopropylpenicillin