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Tethering of two biologically active molecules in a single unit is considered as a captivating solution for the extension of existing antibiotics. β-Lactams which display a vast array of biological properties due to various ring substitutions continue to attract the attention of synthetic chemists. The incorporation of the 'isoxazole' nucleus in its appendage is known to enhance the properties of β-lactam compounds. Its inclusion in the compounds offers decreased toxicity, increased efficacy, and improved pharmacokinetics spectrum. In the reported work, we highlight the efficient use of 1,3-dipolar cycloaddition reaction to synthesize novel isoxazole/dihydroisoxazole ring-linked β-lactam hybrids using 3-propargyloxy-β-lactams/3-allyl-β-lactams as synthons. The methodology devised has been found to be highly regioselective and generalized for the selected substrates to provide a variety of novel hybrid compounds under elementary reaction conditions. The synthesized compounds have been well characterized by various spectroscopic techniques and optimized reaction conditions for both types of hybrid compounds have been studied. [ABSTRACT FROM AUTHOR]

A highly efficient, novel, two‐phase liquid method using phase transfer catalyst is reported to prepare β‐lactam‐conjugated silver nanoparticles as an approach to improve antibacterial activity of β‐lactams. In the method assisted by cetyltrimethylammonium bromide, NaBH4 reduced AgNO3 producing silver NPs that are coated with β‐lactams. The studies conducted provide a generalized method applicable to all types of β‐lactam substrates for capping on silver NPs. The NPs have been characterized by UV–Visible, Fourier transform infrared spectroscopy, x‐ray diffraction, transmission electron microscopy, and dynamic light scattering methods. [ABSTRACT FROM AUTHOR]

This document provides information on the synthesis and characterization of novel β-lactam compounds. The authors conducted studies using different starting materials and reaction conditions, and the results are summarized in tables and schemes. The document also includes detailed experimental procedures and characterization data for the synthesized compounds, such as physical properties and spectroscopic data. The information presented can be useful for researchers studying β-lactam compounds and their properties. The authors acknowledge their affiliations and declare no conflicts of interest. Additional characterization spectra can be found in a separate publication. [Extracted from the article]

A novel, facile, highly efficient and stereoselective protocol for the synthesis of cis-3-allyl-3-phenylsulfinyl-β-lactams and 3-allylidene-β-lactams from cis-3-allyl-3-phenylthio-β-lactams using Selectfluor both as an oxidizing agent and as an eliminating agent with temperature as a control parameter over the reaction outcome has been reported. The methodology is able to conquer the earlier reported shortcomings of long reaction time (24–90 hrs.) and lack of control over product ratio. The synthesized compounds will serve as important synthons for compounds of enhanced biological activity and potency. [ABSTRACT FROM AUTHOR]

An operationally simple, highly efficient and stereoselective method for oxidation of trans‐3‐phenylthio‐β‐lactams to trans‐3‐phenylsulfinyl‐β‐lactams is reported. High selectivity and yields were obtained under mild conditions. The probable mechanistic scheme for the formation of oxidized product is proposed. [ABSTRACT FROM AUTHOR]

A new study on the synthesis of β-lactams functionalized hafnia nanoparticles is done. The reported work describes the utility of hydrothermal method to prepare hafnia nanoparticles coated with β-lactams. The method provides spherical NPs with dimensions of 30–50 nm and are slightly anionic. The conjugate has been found to be biologically active and well characterized by techniques like FTIR, XRD, FESEM, TEM, and EDX methods. The methodology gives a conjugate whose synthesis has not been attempted so far in the literature. [ABSTRACT FROM AUTHOR]