7- Thia-2-azabicyclo heptan-3-ones

Chemical Abstracts most penicillins as 4-thia-l-azabicyclo[3.2.0]heptane-7-ones (2). Using this system, penicillin G [161-33-6] (1, R =... 

The nomenclature of penicillins requires special comment. Compound (2) can be named as follows (a) penicillin G (b) benzylpenicillin (note that the term penicillin may refer to the compound class (1), to the structural fragment (3) or, especially in the medical literature, to compound (2) itself) (c) 6/3-phenylacetamidopenicillanic acid (d) 2,2-dimethyl-6/3-phenylacetamidopenam-3a -carboxylic acid (e) (2S,5i ,6i )-3,3-di-methyl-7-oxo-6-(2-phenylacetamido)-4-thia-l-azabicyclo[3.2.0]heptane-2-carboxylic acid and (f) [2S-(2a,5a,6/3)]-3,3-dimethyl-7-oxo-6-[(phenylacetyl)amino]-4-thia-l-azabicyclo-[3.2.0]heptane-2-carboxylic acid. The numbered system shown in (2) is the one most commonly used in the penicillin literature and will be used in this chapter note that different number is used when (2) is named according to (e) and (f) above. 

Penams. The key step in a synthesis of 6-methyl-4-thia-l-azabicyclo-[3.2.0]heptane-7-one (3) is formation of the p-lactam ring by reaction of 2, prepared... 

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