The share of Klebsiella pneumoniae in infections has been recently increasing. Multidrug-resistant strains that produce more than one antibiotic resistance mechanism are also increasingly isolated. Contamination of the organs preservation fluid occurs quite often, but the isolated microorganisms are mainly saprophytic bacteria that are part of the skin microbiota (coagulase-negative Staphylococcus, Corynebacterium spp). The following case describes a K. pneumoniae blood infection in a patient after liver transplantation. Susceptibility of the strains to chosen antimicrobials was determined using the automated method. For strain isolated from blood, it was confirmed by loop-mediated isothermal amplification of genetic material. © 2021 Indian Association of Medical Microbiologists

The Knoevenagel reaction is an essential synthetic tool in the organic and medicinal chemistry of thiazolidin-4-one derivatives. In the present work, the application of ethylenediamine diacetate (EDDA) as an effective catalyst for the interaction of 2-thioxothiazolidin-4-one with 4-(tert-butyl)cyclohexanone is proposed. The structure of novel synthesized 5-[4-(tert-butyl)cyclohexylidene]-2-thioxothiazolidin-4-one (yield 61%) was confirmed by¹H-,¹³C-NMR, LC-MS, IR, and UV spectra. Drug-like properties of the synthesized compound were evaluated in silico using the SwissAdme, and their potential antimicrobial activity against 15 strains of Gram-positive and Gram-negative bacteria as well as yeasts was evaluated in vitro. The synthesized compound possesses satisfactory drug-like parameters and promising antimicrobial properties and presents interest as a prospective intermediate for the forthcoming design of biologically active small molecules. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Multicomponent reactions effectively contribute to modern organic and medicinal chemistry. 4-Thiazolidinone core and cyclopropyl moiety are important structural motifs for design of potential biologically active molecules. In the present paper, the convenient step-economy and cost-effective synthesis of 2-(cyclopropylamino)-5-(4-methoxybenzylidene)thiazol-4(5H)-one (2) is described based on the application of the MCR methodology. The proposed approach includes direct one-pot interaction of 2-thioxothiazolidin-4-one (rhodanine), 4-methoxybenzaldehyde with cyclopropylamine which was used in 10% excess compare to other reagents. The structure of synthesized compound 2 was confirmed using ¹H, ¹³C, 2D NMR, LC-MS, IR and UV spectra. The presence of prototropic amino/imino tautomerism for synthesized compound 2 was observed based on spectral analysis data. Screening of antimicrobial activity against 12 strains of Gram-positive and Gram-negative bacteria, as well as yeasts, was performed for synthesized derivative 2. © 2022 by the authors.