Monika Mazik

Molecular Recognition of Carbohydrates by Artificial Receptors: Systematic Studies towards Recognition Motifs for Carbohydrates

The synthesis and binding properties for carbohydrates of several artificial, acyclic receptors containing two or three heterocyclic recognition units covalently attached to a phenyl spacer is described. These host molecules having uncharged hydrogen-bonding sites were used in a systematic study towards the evaluation of recognition motifs for carbohydrates. A novel effective, acyclic hydrogen-bonding receptor possessing naphthyridine-amide moieties as heterocyclic recognition units has been developed.

Intermolecular CH⋯N/CH⋯O hydrogen bonds in the crystal structures of α,β-unsaturated ketones carrying a terminal pyridine subunit

Abstract α,β-Unsaturated ketones 1–4 carrying a terminal pyridine subunit form aggregates in the crystalline state with the molecules linked together through CH⋯N/CH⋯O hydrogen bonds. The hydrogen-bonding motifs are discussed.

The potential of CH···N interactions in determining the crystal structures of novel 3,4-disubstituted-5-pyridinyl-isoxazoles

Abstract The crystal structures of novel 3,4-disubstituted-5-pyridinyl-isoxazoles, such as 3-methyl-4-phenyl-5-pyridinyl-isoxazole (1), 4-methyl-3-phenyl-5-pyridinyl-isoxazole (2) and 3,4-diphenyl-5-pyridinyl-isoxazole (3), are governed by significant CH···N interactions.

Hydrogen-bonding motifs in the crystals of secondary diamides with 2-amino-6-methyl- and 2,6-diaminopyridine subunits

Abstract Hydrogen-bonding motifs in the crystal structures of N,N′-bis-(6-methyl-pyridin-2-yl)-isophthalamide (1), 1,3-bis[[(6-methyl-pyridin-2-yl)amino]carbonyl-methyloxy]benzene (2), N,N′-bis-(6-amino-pyridin-2-yl)-isophthalamide (3) and 1,3-bis[[(6-amino-pyridin-2-yl)amino]carbonyl-methyloxy]benzene (4) are reported. The hydrogen bond preferences were analyzed.

Control of molecular self-assembly by hydrogen-bonding and aromatic interactions: Formation of discrete cyclic tetrameric aggregates

Abstract Four molecules of 3-phenyl-4-pyridin-4′-yl-3-buten-2-on-oxime 1 form discrete cyclic aggregates stabilized by a network of 8 hydrogen bonds and stacking interactions.

Trimethoxybenzene- and trimethylbenzene-based compounds bearing imidazole, indole and pyrrole groups as recognition units: synthesis and evaluation of the binding properties towards carbohydrates

The aim of the study was to evaluate the potential of trimethoxybenzene- and trimethylbenzene-based compounds bearing imidazole or indole groups as recognition sites in the complexation of carbohydrates. Representatives of these compounds were prepared and their binding properties toward selected carbohydrates evaluated. The results of the binding studies were compared with those obtained for the prepared pyrrole bearing analogues and for the previously described triethylbenzene-based receptors.

New helical hydrogen-bonded assemblies forming channel-inclusion complexes

Helical hydrogen-bonded assemblies of 2-methyl-1-phenyl-3-pyridin-4′-yl-2-propen-1-on-oxime create three-dimensional networks containing large channels with hydrophobic environments, which are able to trap suitable guest molecules.

Programmed Construction of Discrete Self‐Assembled Cyclic Aggregates

Examples for programmed self-assembly of alpha,beta-unsaturated ketoximes carrying a terminal pyridine subunit are described. The solid-state structures of a series of pyridinyl alpha,beta-unsaturated ketoximes 1 were investigated by X-ray structural analysis; this demonstrated that molecules 3-5 predictably form discrete cyclic aggregates stabilized by a network of hydrogen bonds and aromatic interactions.

Reaction of 1,2-diketones with N,N-dimethylcyanamide in the presence of titanium(IV) chloride.

1,2-Diketones RCOCOR (R = Ph, p-tolyl, m- or p-anisyl, Me) undergo TiCl4-catalyzed [2 + 2] cycloaddn. to N,N-dimethylcyanamide with subsequent ring opening to give 1:1 adducts RCOCR:NCONMe2 and 1:2 adducts Me2NCON:CRCR:NCONMe2 (10). The structure of 10 (R = Ph) was established by X-ray anal.

Trimethyl-, triethyl- and trimethoxybenzene-based tripodal compounds bearing pyrazole groups: conformations and halogen-/hydrogen-bond patterns in the crystalline state

X-ray analyses of a series of benzene-based tripodal molecules 1–9, bearing either bromo-substituted pyrazole groups or analogues lacking the bromo substituents, provide interesting insights into the molecular recognition phenomena and also give information about the different conformations which adopt the tripodal molecules in the solvent-free crystals and in solvates. The crystal packings are characterized by the presence of C–H⋯O, C–H⋯N, C–H⋯Br and C–H⋯Cl hydrogen bonds as well as C–Br⋯N, C–Br⋯Br, C–Br⋯Cl and C–Br⋯π halogen bonds. The conformations observed in the case of the triethyl- and trimethoxybenzene-based compounds can be defined as ababab, ababba, ababbb, abaaba, abaabb, aaabba and aaaaaa with the pyrazole-bearing arms arranged either in an aaa or an aab fashion.