A series of new 4-(1,3,4-thiadiazol-2-yl)-containing polysubstituted pyrroles 3 a-k has been synthesized by a preparative convenient method from ethyl 5-chloro-4-formyl-1H-pyrrole-3-carboxylates 1 a-e, which were selectively transformed into the corresponding polysubstituted pyrrole-4-carboxylic acids 2 а-е using sodium hypochlorite as an oxidizer. Further, they were transformed into the target compounds with a high yield using the cyclocondensation with N-mono- or N,N-disubstituted thiosemicarbazides in the boiling phosphorus trichloroxide. As seen from the screening of antimicrobial activity, the synthesized compounds exhibit the inhibiting and bactericide activity against some bacteria and fungi. The highest activity has been established for the compounds 3 a, c, e-h, j against the strain Klebsiella pneumoniae (МІС=31.25 µg/mL). The calculated HOMO energy level proves that the compound 3 с is the most reactive ligand for the interaction with a protein receptor. The molecular docking data show that the compound 3 h has the highest affinity to the ThiM Klebsiella pneumoniae kinase.

A series of new derivatives of 3-(pyrrol-4-yl)acrylamides 3a-l with the pyrrole nucleus functionalized by chlorine atoms and ester group, have been synthesized by simple preparative methods from the available esters of 5-chloro-4-formylpyrrol-3-carboxylic acids 1a-e. At first, 3-(pyrrol-4-yl)acrylic acids 2a-e were synthesized by the Knoevenagel’s reaction between malonic acid and the esters 1a-e. Then the target compounds were obtained with a high yield in the reactions between chloroanhydrides of the synthesized acrylic acids and aromatic or aliphatic amines in the boiling benzene. The structure of all obtained compounds was confirmed by elemental analysis, IR, ¹H-NMR, and ¹³C-NMR spectroscopy, and additionally checked by the mass-spectrometry. Then the antimicrobial activity of all amides was tested in vitro on some gram-positive and gram-negative bacteria and fungi. It has been found that the gram-negative bacteria are resistant against the synthesized chemicals, while the gram-positive bacteria are sensitive to the amides 3с, e, f, g, i. The highest activity against Staphylococcus aureus MR and Staphylococcus epidermidis MS was registered for the amide 3f, and the retardation area diameter for this amide was greater than that for the control drugs.