For the first time, derivatives of 3,7-diazabicyclo[3.3.1]nonane (bispidine) were proposed as potential inhibitors of the SARS-CoV-2 main viral protease (3-chymotrypsin-like, 3CLpro). Based on the created pharmacophore model of the active site of the protease, a group of compounds were modeled and tested for activity against 3CLpro. The 3CLpro activity was measured using the fluorogenic substrate Dabcyl-VNSTLQSGLRK(FAM)MA; the efficiency of the proposed approach was confirmed by comparison with literature data for ebselen and disulfiram. The results of the experiments performed with bispidine compounds showed that 14 compounds exhibited activity in the concentration range 1–10 μM, and 3 samples exhibited submicromolar activity. The structure–activity relationship studies showed that the molecules containing a carbonyl group in the ninth position of the bicycle exhibited the maximum activity. Based on the experimental and theoretical results obtained, further directions for the development of this topic were proposed.

Stable negative ions containing up to sixteen silicon atoms have been measured by mass spectromettry in RF power-modulated silane plasmas for amorphous silicon deposition. These hydrogenated silicon cluster ions reach much higher masses than the positive ions, which have no more than six silicon atoms. This supports the view that negative ions are the precursors to particulate formation in silane plasmas. The time-dependent fluxes d positive and negative ions from the plasma are shown with a 5 p s time resolution. Possible cluster reaction sequences are discussed and the effect of visible light on the negative ion signal i s commented upon.

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The effect of the emission layer deposition method on the characteristics of OLEDs was studied on the example of the europium mixed ligand complex Eu(tta)3DPPZ (tta: 2-thenoyltrifluoroacetone, DPPZ: dipyrido[3,2-a:2’c,3’c-c]phenazine), which...

A new series of dicarboxylic derivatives of bispidines have been synthesized to develop novel copper(II) complexes suitable as imaging agents for positron emission tomography. For characterization purposes, copper complexes of bispidines were synthesized in the pure form and in quantitative yields by neutralization of ligands with malachite. The formation of complexes and their stoichiometries were studied by potentiometric titration, cyclic voltammetry, and spectroscopic methods. The stability constants were found to be fairly suitable for copper cation fixation inside dianionic chelate molecules.

Novel [LPdCl] 3 trimers (L ) chiral secondary benzylamine) were synthesized via direct cyclopalladation. The structures of trimeric palladacycles were confirmed by means of X-ray analysis. The secondary interactions stabilizing trimeric molecules were investigated. An equilibrium between dimeric and trimeric palladacycle species was found in solution by means of dynamic NMR-spectroscopy and ESI mass spectrometry study.

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