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β-Lactam antibiotics have occupied a central role in the fight against pathogenic bacteria and the subsequent rise in quality of life for the world population as a whole. However, the extensive use of common β-lactam antibiotics such as penicillins and cephalosporins in medicine has resulted in an increasing number of resistant strains of bacteria through mutation and β-lactamase gene transfer. The...
β-Lactam rings containing compounds are a group of antibiotics of unparalleled importance in chemotherapy. Considerable effort has been reported in the development of novel, more effective β-lactam compounds as well as their biological evaluation. This article reviews the progress made in the stereoselective synthesis of spiro-β-lactams, a unique class of heterocycles, their biological evaluation,...
In this chapter, a comprehensive overview of the most significant and interesting contributions published from 2000 until now, concerning the preparation of novel β-lactam structures is presented. Among the different synthetic strategies available, either novel or already known but efficient and versatile methodologies are covered. The simple modifications of one or more substituents linked to the...
The main strategies for the ring opening of β-lactams by chemical means are described. The discovery of each approach is put into context, sometimes in connection to processes occurring in biological systems, and the synthetic opportunities each approach offers are shown. Thus, this β-lactam route affords a number of synthetically relevant building-blocks, including α-amino acids, β-amino acids, their...
Since the discovery of penicillin in 1929, β-lactam antibiotics have been recognized as potentially chemotherapeutic drugs of incomparable effectiveness, conjugating a broad spectrum of activity with very low toxicity. The primary motif azetidin-2-one ring (β-lactam) has been considered as specific pharmacophores and scaffolds. With the advent of combinatorial chemistry and automated parallel synthesis...
The main computational studies on the formation of β-lactams through [2+2] cycloadditions published during 1992–2008 are reported with special emphasis on the mechanistic and selectivity aspects of these reactions. Disconnection of the N1-C2 and C3–C4 bonds of the azetidin-2-one ring leads to the reaction between ketenes and imines. Computational and experimental results point to a stepwise mechanism...
Stereocontrolled synthesis of racemic and chiral novel β-lactams using polyaromatic imines has been accomplished. Domestic and automated microwave-induced reactions have been investigated for the preparation of these types of β-lactams. A preliminary mechanism of this reaction has been advanced. Formation of trans-β-lactams has been explained through isomerization of the enolates formed during the...
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