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The geometric parameters of dl- and d-tetranuclear iron(III) tartrates [Fe4(d-L)2(l-L)2(H2O)8]4–and [Fe4(d-L)4(H2O)8]4–(H4L is tartaric acid) were optimized using the molecular mechanics method (MIND program, Dashevskii–Plyamovatyi model).

The reactions of 1,3-bis(ω-bromobutyl- or -pentyl)-6-methyluracil with 1,3-bis(ω-ethylaminobutyl- or -pentyl)-6-methyluracil afforded pyrimidinophanes containing N atoms in bridging polymethylene chains. Individual geometric isomers of pyrimidinophanes were isolated. The structure of one of these isomers was established by X-ray diffraction analysis. Quaternization of the bridging N atoms with o-nitrobenzyl bromide gave rise to water-soluble pyrimidinophanes.

Formation of heteronuclear erbium(III), thulium(III), and iron(III) d- and dl-tartrates was studied by proton magnetic relaxation, pH-metry, and paramagnetic birefringence in combination with mathematical simulation. The paramagnetic birefringence constants mP of the complexes were calculated.

The catalytic effect of new amphiphilic pyrimidinic compounds with two ammonium head groups and different kinds of counterions, inorganic bromide anions and hydrophobic tosylate anions, was studied and compared with that of conventional cetyltrimethylammonium surfactants with bromide and tosylate counterions.

The cyclization of 1,3-bis(ω-bromoalkyl)uracils with sodium sulfide led to pyrimidinophanes, containing one uracil unit and an S atom in the spacer, macrocyclic structure was confirmed by X-ray data; the S atom in bridge can be oxidized into sulfoxide or sulfone or converted into sulfonium ion.

Cationic dimeric pyrimidinic surfactants have been synthesised; the aggregation and catalytic properties of supramolecular systems based on these surfactants and polyethyleneimine have been studied.

Two novel macrocyclic 6-methyluracilic amphiphiles (uracilophanes) with four (UP1) and two (UP2) uracil moieties and ammonium groups have been synthesized. Tetracationic multi-uracilophane is composed of two macrocyclic units bridged each other with an external methylene spacer, while in the cryptand-like dicationic uracilophane pyrimidinic moieties are connected with an internal methylene spacer. This internal spacer provided a conformational rigidity to the macrocycle. The self-assembly of the uracilophanes is studied and compared with a reference dicationic uracilophane (UP3) with no spacer fragment. Compounds UP1 and UP3 are capable of aggregating, which is characterized by the analogous critical micelle concentration of 1 mM, although the former has four decyl tails versus two decyl tails in UP3 molecule. NMR self-diffusion, fluorimetry and DLS techniques revealed that bimodal size distribution occurs in the UP1 solution, with small (≤ 2 nm) and large (ca. 30–50 nm) aggregates contributed. Unexpectedly, the cryptand-like uracilophane UP2 with the same hydrophobicity as UP3 does not form aggregates. The balance of the geometry and energetic factors was analyzed and compared with those contributing to the aggregation of the reference compound UP3. It was established that it is the geometry that controls the packing of the cryptand-like uracilophanes upon aggregation, while hydrophobic effect plays a minor role. In contrast, both factors control the aggregation of oligomeric macrocycle, with energetic factor prevailing. These findings are of importance for (i) the understanding the diverse structural behavior of bioamphiphiles that have very similar chemical structure, but different conformations; and (ii) the design of amphiphiles with controlled model of self-assembly. Supramolecular systems studied can be recommended for biotechnological applications.

Tunable nanosystems based on a novel water insoluble pyrimidinic amphiphile are designed. pH dependent aggregates composed of protonated pyrimidinophane 1 are formed at pH

Reactions of pyrimidinophanes with two 6-methylthiocytosine and one 5(6)-alkyluracil moieties bridged with each other by polymethylene spacers with methyl or nonyl p-toluenesulfonate, p-toluenesulfonic acid, methanesulfonate and trifluorosulfonate afforded amphiphilic macrocyclic bis-p-toluene-, methane- and trifluorosulfonates. Despite the presence of several reaction centers in the initial pyrimidinophane molecules, protonation and methylation occurred only at the N(1) atom (with quaternization) of the 6-methylthiocytosine moieties. The bacteriostatic and fungistatic activity of the products was estimated. Macrocyclic tosylates exhibit a remarkable selectivity towards Staphylococcus aureus, with MIC values comparable with a reference drug. Bacteriostatic activity of the amphiphilic pyrimidinophanes depends on the size of the macrocycles, and the highest activity corresponds to definite lengths of polymethylene bridges. Besides, the antimicrobial activity of the screened pyrimidine derivatives depends on their topology. While macrocyclic tosylates are more active against bacteria than against fungi, acyclic tosylate with the same structural fragments shows a dramatical decrease of MIC towards mold and yeast with respect to the corresponding macrocycle. It is found that macrocyclic and acyclic tosylates in high dilutions decrease the extracellular lipase activity.

The reactions of stoichiometric amounts of sodium salts of 2-hydroxy-3-methyl-4-oxo-3,4-dihydropyrimidine or 2-hydroxy-3,6-dimethyl-4-oxo-3,4-dihydropyrimidine and dibromoalkanes in dimethylformamide were used to synthesize α,ω-bis(3-methyl- or 3,6-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-1-pyirimidinyl)alkanes with 1 and 3-5 methylene units in the hydrocarbon brigde.

The cyclization of 1,3-bis(ω-bromoalkyl)uracils with sodium sulfide led to pyrimidinophanes, containing one uracil unit and an S atom in the spacer, macrocyclic structure was confirmed by X-ray data; the S atom in bridge can be oxidized into sulfoxide or sulfone or converted into sulfonium ion.

New pyrimidinophanes containing four uracil units connected with methylene bridges through the N(1) and C(5) atoms of pyrimidine rings were obtained by treatment of 1,4-bis(3,6-dimethyluracil-1-yl)butane with paraform.

pH-Metering and magnetic double refraction are used to determine the molar constant of magnetic double refraction of dysprosium monotartrate DyH2L+ (H4L is tartaric acid). A molecular mechanics technique (Dashevskii-Plyamovatyi model) was used to model the structure of the ligand and hydrate surroundings of dysprosium(III) in DyH2L+. Theoretical molar constants of magnetic double refraction calculated from the molecular mechanics data (CONKERR program) were compared with the experimental values; the most probable models of the surroundings of the dysprosium(III) are established.

Reactions of 1,3-bis(ω-bromoalkyl)-substituted uracils, quinazoline-2,4-dione, and 5-methyl-1,3,5-triazine-2,4,6-trione and 1,3-bis(m-bromomethylbenzyl)-5-bromouracil with amines (aliphatic amines, benzylamines, naphthylmethanamine, and anisidine) gave a series of macrocyclic compounds having one pyrimidine or triazine fragment and an azapolymethylene bridge connecting the N1 and N3 atoms of the heteroring. The bridging nitrogen atom in some macrocyclic compounds was subjected to quaternization with methyl p-toluenesulfonate.

Protonation (alkylation) sites of several thiopyrimidine derivatives were directly determined by 1H−15N (1H−13C) heteronuclear single quantum coherence/heteronuclear multiple bond correlation methods, and it was found that in all compounds, protonation (methylation) occurred at the N1 nitrogen. GIAO DFT chemical shifts were in full agreement with the determined tautomeric structures. According to ab initio calculations, the stability of the different protonated forms and methylated derivatives was favored due to thermodynamic control and not kinetic control.

The reactions of 1,3-bis(alpha,omega-bromoalkyl)-6-methyluracils with 1,3-bis(alpha,omega-ethylaminoalkyl)-6-methyluracils or 1,3-bis(bromopentyl)thymine with butylamine afforded pyrimidinophanes containing one or two uracil units and nitrogen atoms in bridging polymethylene chains. In some cases individual geometric isomers of pyrimidinophanes differing in the mutual arrangement of the carbonyl and methyl groups at different pyrimidine rings were isolated. Quaternization of the bridging nitrogen atom with o-nitrobenzyl bromide, benzyl bromide, n-decyl bromide gave rise to water-soluble pyrimidinophanes which were evaluated for their antibacterial and antifungal activity. The arrangement of the carbonyl groups in macrocycles doesn't affect the activity. Antibacterial and antifungal activity of pyrimidinophanes increases with the increase of polymethylene N(pyr)-N-chain length and dramatically increases upon the introduction of n-decyl substituent at nitrogen atoms in spacers. Pyrimidinophanes with 5 and 6 methylene groups in N(pyr)-N-chain and n-decyl substituent showed significant bacteriostatic, fungistatic, bactericidal, fungicidal activity which comparable with standard antibacterial and antifungal drugs. Acyclic counterpart demonstrated the highest activity against fungi. Toxicity of more effective pyrimidinophanes was determined for mice and Daphnia magna Straus.

The reactions of 1,3-bis(alpha,omega-bromoalkyl)-6-methyluracils with 1,3-bis(alpha,omega-ethylaminoalkyl)-6-methyluracils or 1,3-bis(bromopentyl)thymine with butylamine afforded pyrimidinophanes containing one or two uracil units and nitrogen atoms in bridging polymethylene chains. In some cases individual geometric isomers of pyrimidinophanes differing in the mutual arrangement of the carbonyl and methyl groups at different pyrimidine rings were isolated. Quaternization of the bridging nitrogen atom with o-nitrobenzyl bromide, benzyl bromide, n-decyl bromide gave rise to water-soluble pyrimidinophanes which were evaluated for their antibacterial and antifungal activity. The arrangement of the carbonyl groups in macrocycles doesn't affect the activity. Antibacterial and antifungal activity of pyrimidinophanes increases with the increase of polymethylene N(pyr)-N-chain length and dramatically increases upon the introduction of n-decyl substituent at nitrogen atoms in spacers. Pyrimidinophanes with 5 and 6 methylene groups in N(pyr)-N-chain and n-decyl substituent showed significant bacteriostatic, fungistatic, bactericidal, fungicidal activity which comparable with standard antibacterial and antifungal drugs. Acyclic counterpart demonstrated the highest activity against fungi. Toxicity of more effective pyrimidinophanes was determined for mice and Daphnia magna Straus.

The reactions of disodium salts of N,N"-bis(2-mercapto-6-methylpyrimidin-4-yl)alkylenediamines with 1,3-bis(ω-bromoalkyl)-6-methyluracils afforded a series of macrocyclic compounds containing three pyrimidine fragments with different numbers of methylene groups in linking bridges.

The structures of the ligand and hydrate environments of dysprosium(III) have been determined for dysprosium(III) d - and dl -tartrates in aqueous solution.

A series of acyclic and macrocyclic nucleobase derivatives that contain uracil and 2-thiocytosine units linked by polymethylene spacers was prepared. The length of spacers as well as the oxidation number of sulfur atoms entering into the structure of the compounds was varied. The crystal structure of pyrimidinophane with hexa- and heptamethylene linkers was established by X-ray analysis. The metal ion-binding properties of pyrimidinophanes and their acyclic counterparts were investigated by liquid extraction and 1H NMR titration experiments. The compounds with 2-thiocytosine fragments revealed a high selectivity of extraction towards Ag+ ions. The stoichiometry of silver complexes and the binding constants have been determined. The antibacterial activity of these complexes was also discussed.

New pyrimidinophanes containing four uracil units connected with methylene bridges through the N(1) and C(5) atoms of pyrimidine rings were obtained by treatment of 1,4-bis(3,6-dimethyluracil-1-yl)butane with paraform.