β-Lactams:  Versatile Building Blocks for the Stereoselective Synthesis of Non-β-Lactam Products

Abstract

4468 3. Synthesis of Amino(hydroxy) Acid Derivatives 4474 3.1. β-Amino Acids 4474 3.2. R-Hydroxy-β-amino Acids 4480 3.3. R-Amino Acids 4482 4. Synthesis of β-Amino Ketone Derivatives 4484 5. Synthesis of γ-Amino Alcohol Derivatives 4485 6. Miscellaneous 4486 7. Conclusions 4489 8. Abbreviations 4489 9. Acknowledgments 4489 10. References 4489

Synthesis and Biological Activity of a Series of Novel N‐Substituted β‐Lactams Derived from Natural Gallic Acid

“…[11][12][13][14][15][16] Especially, the monocyclic b-lactams namely azetidinones, are an important part of the b-lactams antibiotic scaffold, which are always obtained via classical Staudinger ketene-imine cycloaddition reaction [17][18][19][20][21][22] and are known to exhibit interesting and broad biological activities. A large number of monocyclic b-lactams possess powerful antibacterial, antimicrobial, anti-inflammatory, anti-convulsant, anti-viral and antitubercular activity etc.…”

Divergent, stereoselective access to heterocyclic α,α-quaternary- and β2,3,3-amino acid derivatives from a N-Pmp-protected Orn-derived β-lactam

“…The intermolecular nucleophilic ring opening of N-Boc-β-lactams has also been successfully applied to the synthesis of β-amino acids, β-amino-α-hydroxy acid and β,β-disubstituted-β-amino acid derived peptides. 38,39 Based on these precedents, we envisaged a route for the preparation of conformationally restricted 2-piperidinone-containing β-amino acid derivatives, using again β-lactam 7 as the key precursor. Thus, removal of the Z protecting group from 7 by catalytic hydrogenation promoted the formation of the 3.5-spiro derivative 11 in good yield (84%), through a 6-exo-trig ring closure (Scheme 3).…”

Synthesis of some new spirocyclic β-lactam and spirocyclic thiazolidin-4-one derivatives

“…Structural reasoning for 7-(4-amino-3-cyano-5,10-dioxo-1,5,10, Among the several methods for the synthesis of β-lactams, the cycloaddition reaction of Schiff bases with ketenes (Staudinger reaction) [43,44] is mostly applied. This method has been used for the synthesis of a large number of monocyclic, bicyclic, tricyclic and spirocyclic β-lactams [1]. The α-methylene protons in chloroacetyl chloride are activated due to the electron-withdrawing inductive effect (-I) effect exerted by the adjacent chlorine atom and the carbonyl group.…”

“…β-Lactam as synthetic intermediate has been widely recognized in organic synthesis because it is an active moiety present in most widely used antibiotics such as penicillin, cephalosporins, carbapenems, nocardicins and monobactams [1]. In addition to their use as antibiotics, β-lactams are increasingly being used as synthons for other biologically important molecules [2].…”