The Chemistry of β-Lactams

It is over sixty years since Alexander Fleming observed antibiosis between a Penicillium mould and bacterial cultures and gave the name penicillin to the active principle. Although it was proposed in 1943 that penicillin (1) contained a tJ-Iactam ring, this was not generally accepted until an X-ray crystallographic determination of the structure had been completed. RCONH )=r)