Stereochemistry and ring opening of a carbocyclic analogue of a 1-oxapenam

✍ Scribed by Demetrios Agathocleous; Graham Cox; Michael I Page

• Book ID: 104218416
• Publisher: Elsevier Science
• Year: 1986
• Tongue: French
• Weight: 173 KB
• Volume: 27
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)84333-6

✦ Synopsis

The cycloaddition of succinimido ketene to 2,3_dihydrofuran yields 7-exo-succinimido bicycle C3.2.01 2-oxoheptan-6-one. This unusual stereo-chemistry is confirmed by 'H NMR and X-ray crystallography. The cyclobutanone product undergoes ring opening in concentrated hydrochloric acid to give 1-succinimido-5-chloro-2-pentanone. #e have shown that B-lactam antibiotics do not exhibit unusual chemical reactivity and that a pyramidal nitrogen does not significantly reduce amide resonance in bicyclic Blactams.' ' Consequently we have reported that cyclobutanone analogues of the ,&lactams may inhibit transpeptidase and B-lactamase enzymes by formation of hemi-ketals or by ring opening of the four-membered ring using the enzymes active serine hydroxyl residue.3 The synthetic strategy we have previously used for introducing the required acylamino substituent into the carbocyclic analogues of penicillin is to use the addition of phthalimido-and succinimido-ketenes to C=C bonds:3