Imidazolidin-2-one and 1,3-benzodiazepin-2-one scaffolds are structural motifs of many biologically active compounds. Herein, we report a highly regioselective acid-catalyzed intramolecular nucleophilic cyclization/intermolecular electrophilic substitution reaction sequence of (2,2-dialkoxyethyl)ureas. The reaction benefits from readily available starting materials, a simple workup procedure, moderate to high yields of target compounds, and provides a convenient entry to previously unknown 4-(het)arylimidazolidinones and 5-(het)arylbenzodiazepinones. The proposed mechanism of the reaction is also discussed.

No abstract

No abstract

The rare example of pyrrolidine C–N bond cleavage in 1-sulfonylpyrrolidines in acidic media in the presence of phenols is reported. The reaction proceeds under mild conditions and provides a convenient route to otherwise hardly accessible and previously unknown dibenzoxanthenes, diarylbutanes, and resorcinarenes having a sulfonylamide moiety.

No abstract

A novel tandem reaction, which transforms N-(4,4-diethoxybutyl)imines to 3-arylidene-1-pyrrolines via intramolecular Mannich reaction/[1,3]-sigmatropic rearrangement of the aryl fragment is described.

Conformations and dynamics of 1,5-diaza-3,7-diphosphacyclooctane (1) with chiral l-menthyl substituents on the phosphorus atoms and several metal complexes thereof were investigated by a variety of DNMR methods. In solution 1 adopts a C(2) symmetrical "crown"-like conformation (CW) and the conformational preference and dynamics of the complexes depend on the type of metal: for the Cu complex the CW form is preferred, whereas the Pd, Pt, or Mo complexes exist in an equilibrium of two "chair-boat"-like conformations (CB/CB*). The barriers of interconversion between these two conformations for the Pd and Pt complexes are about 2 times higher than for the Mo complex. Quantum chemical calculations (B3LYP/6-31G(d)) are in agreement with experimental findings.

A first successful synthesis of 2‐(pyrazolyl)pyrrolidines is reported starting from readily available reagents. A wide variety of N‐substituted 2‐(pyrazolyl)pyrrolidines are obtained with up to 96 % yield. The influence of the obtained compounds on biofilm formation by V. aquamarinus DSM 26054 and A. calcoaceticus VKPM B–10353 have been studied. Some of the tested compounds were found to suppress the growth of bacterial biofilms at nanomolar concentrations and thus are promising candidates for further studies.