The application of various isonitrile-based multicomponent reactions to protected (2-oxoethyl)boronic acid (as the carbonyl component) is described. The Ugi reaction, both in the four components and in the four centers-three components versions, and the van Leusen reaction, proved effective at providing small libraries of MIDA-protected β-aminoboronic acids. The corresponding free β-aminoboronic acids, quantitatively recovered through basic mild deprotection, were found to be quite stable and were fully characterized, including by 11B-NMR spectroscopy. Single-crystal X-ray diffraction analysis, applied both to a MIDA-protected and a free β-aminoboronic acid derivative, provided evidence for different conformations in the solid-state. Finally, the antimicrobial activities of selected compounds were evaluated by measuring their minimal inhibitory concentration (MIC) values, and the binding mode of the most promising derivative on OXA-23 class D β-lactamase was predicted by a molecular modeling study.

中文翻译：

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基于异腈的多组分合成β-氨基硼酸作为β-内酰胺酶抑制剂。

描述了将各种基于异腈的多组分反应应用于受保护的（2-氧乙基）硼酸（作为羰基组分）。在四个组分和四个中心-三个组分的版本中，Ugi反应和van Leusen反应均被证明可有效提供MIDA保护的β-氨基硼酸的小型文库。发现通过基本的轻度脱保护定量回收的相应的游离β-氨基硼酸非常稳定，并已通过11B-NMR光谱进行了全面表征。应用于MIDA保护的和游离的β-氨基硼酸衍生物的单晶X射线衍射分析提供了固态不同构象的证据。最后，