During World War II there was a huge effort to synthesize penicillin. Is the beta carbon, and then we hit the nitrogen. If we wanted to classify this lactam, the carbon next to theĬarbonyl is the alpha carbon. It's an amide in a ring, and we can see that here is our lactam. You could change into amoxicillin or ampicillin or anything like that. Structure for penicillin here, or a penicillin derivative,īy changing the R group. There's a special one in penicillin, an amide in a ring, We said this is why amidesĪre generally unreactive here. That allows this lone pair ofĮlectrons to be delocalized, which increases the electronĭensity around our carbonyl carbon, so that makes our carbonyl carbon less electrophilic, and In an ideal amide the planar nitrogen gives the best overlap of orbitals. Obviously Sp2 hybridized here, indicating that the nitrogen is planar. State of nitrogen in this resonance structure, it's Structure on the right and we think about the hybridization That would give the nitrogenĪ plus one formal charge. Negative one formal charge, and it would be a double bond between the carbon and the nitrogens. Structure for an amide, this top oxygen here gets a We know that the lone pair of electrons on nitrogen is not localized to the nitrogen, it's delocalized, it
Lactams are technically amides, however they're differentįrom typical amides. Lecturer: In this video we're going to look at beta-lactam antibiotics.
