Dehydroacetic acid thiosemicarbazone and its copper(II) complexes have been synthesized and characterized by elemental analyses, IR, VIS-UV, magnetic susceptibility, conductivity, DTA and ESR spectra. Molar conductance indicates that the complexes are non-electrolytes except for [Cu(H₂L)]SO_{4^.2H2O. The ESR spectra of the complexes show axial type symmetry with g|| >> g- >> 2.00, indicating dx²-y² ground state with significant covalent bond character.}

The phase diagrams of AgGaS₂/AgInS₂/-HgS sections in the quasi-ternary Ag₂S-HgS-Ga₂S₃/In₂S₃/systems have been constructed using differential thermal, X-ray phase and microstructural analyses. AgGaS₂-HgS section is quasi-binary and belongs to the eutectic type. The coordinates of the eutectic point are 76 mol% HgS and 1018 K. AgInS₂-HgS is not quasi-binary above the solidus. In the AgGaS₂-HgS system the limited solid solutions within the composition range 0-2 mol% HgS and 82-98 mol% HgS at 670 K were discovered. The compounds AgInS₂ and HgS form limited solid solutions within the composition range 0-2 mol% HgS and 71-95 mol% HgS at 670 K. The solid solutions, in the part HgS-rich, are created on the basis of the low temperature cubic structure (-HgS) on both sections.

The synthesis and characterization of (NH₂RNH₂)₃CuCl₂^.H₂O complexes, where R = (-CH₂-)₃ or (-CH(CH₃)-CH₂-) are reported. The complexes are octahedral. The ESR spectra of polycrystalline samples showed broad lines, which indicate spin-exchange interactions between copper(II) ions. In solution at 77 K, the spectra show axial type symmetry with d_x²-y² ground state of a tetragonal distortion around copper(II) ion. The bonding parameters ₂² and ß₁² indicate a covalent character of in-plane and bondings, while ß² indicates ionic out-of-plane bondings. d-Orbital populations of the complexes indicate, that the unpaired electron site is mainly in d_x²-y² orbital.

From M(II)-Y^--4-X-pz systems, where M = Cu, Ni, Co; Y = NCO, C(CN)₃, N(CN)₂; X = Cl, Br, I (pz = pyrazole), new compounds of the type [MY₂(4-X-pz)₂] and [M(4-X-pz.Y)₂] have been prepared. Compounds [M(4-X-pz.Y)₂] arise by nucleophilic addition of imine nitrogen from 4-X-pz to cyano carbon of the pseudohalide under formation of five-membered metallocycle. The influence of X substituent on the course of this reaction with various M(II) and Y was investigated. An uncomplete course of nucleophilic addition is revealed by formation of mixed products, consisting of [MY₂(4-X-pz)₂] and [M(4-X-pz.Y)₂]. All compounds were studied by infrared and electronic spectroscopy and probable structures were assigned to the relevant species.

In the ternary system MgO-Na₂O-P₂O₅ the binary system Mg₃(PO₄)₂-Na₃PO₄ was investigated by thermal analysis, X-ray and microscopy, and its phase diagram was proposed. Three intermediate compounds occur in this system with the molar ratio Mg₃(PO₄)₂:Na₃PO₄ 4:1, 1:1 and 1:4, and corresponding formulas Mg₄Na(PO₄)₃, MgNaPO₄ and MgNa₄(PO₄)₂. The phosphate Mg₄Na(PO₄)₃ melts incongruently at 1155°C, the MgNa₄(PO₄)₂ melts congruently at 1655°C, whereas the phosphate MgNaPO₄ occurs only in the solid phase, which undergoes decomposition at 950-960°C. The polymorphism of these phosphates was investigated and temperatures of polymorphic transitions were determined.

Phase diagrams in the AgInSe₂-Ag₈GeSe₆ and AgInSe₂-Ag₈SnSe₆ systems have been constructed using differential thermal, X-ray phase and microstructural analyses. Both sections are quasibinary and of eutectic type and contain homogeneity ranges on the base of initial compounds.

The thermal decomposition of the complexes Mg(Clac)₂(pic)₂^.3H₂O (I), Mg(Cl₂ac)₂(pic)^.4H₂O (II) and Mg(Cl₃ac)₂(pic)₂^.3H₂O (III), where Clac = ClCH₂COO^-, Cl₂ac = Cl₂CHCOO^-, Cl₃ac = Cl₃CCOO^- and pic = -picoline had been investigated in air by TG and DTA. The possible scheme of destruction of the complexes is suggested. The final product was MgO for the complexes I-III. The thermal stability of the complexes can be ordered in the sequence: I = III << II. IR data suggest a unidentate coordination of carboxylates to Mg(II) in complexes I-III and -picoline coordination with Mg(II) through the nitrogen atom of its heterocyclic ring.

Molecular mechanics calculations (using MM+, MMX and AMBER force fields) of all constitutional and topological isomers of C₆₀H₅₈R¹R² with R¹, R² = H, Me revealed that "in,in" isomers are always the most stable, while the corresponding "out,out" isomers have the biggest energy. Moreover, a substitution of an "in" hydrogen atom by a methyl group in the confined volume of the C₆₀ cage does not change, or even lowers, the steric energy. The dependence of steric energy on the distance between the "in" hydrogen atoms (or between the carbon atoms of "in" methyl groups) reveals highly irregular behaviour, for close neighbours, reflecting differences in the energies associated with considerable distortions of the fullerane skeleton.

A series of variously N-substituted (2-furyl)aminomethanephosphonous acids was synthesized in fair yields. The synthesis of optically pure (S)-(2-furyl)-(R)-N--methylbenzylaminomethanephosphonous acid is also presented.

The solid-phase synthesis of -hydroxymethylserine peptides is affected by accummulation of deleted sequences and NO-acyl migrations, occurring under acidic conditions of cleavage from Wang resin. The conformational behaviour of peptides, containing alanine host-residues separated by a single or consecutive -hydroxymethylserine (HmS) guest-residues, has been studied by CD spectroscopy in polar protic solvents. The presence of sequential motif (Ala-HmS)_n, n = 2, 4, shifts the conformational equilibria towards ordered structures. The CD spectrum of the nonapeptide Ac-Ala-(HmS-Ala)₄-OH in trifluoroethanol is indicative of a right-handed helix. Peptides with consecutive HmS_n residues, n = 2, 3, are apparently less ordered than those containing alternating sequences Ala-HmS. Random coil conformation is adopted by the nonapeptide Ac-Ala₃-(HmS)₃-Ala₃-OH containing three neighbouring HmS residues.

Reaction of 2-aminonicotinic acid hydrazide with cyanogen bromide allowed to obtain 2-amino-5-(2-amino-3-pyridyl)-1,3,4-oxadiazole (2), which with 2- or 3-chloropropionyl chloride and 4-chlorobutyryl chloride gave 5-(2-amino-3-pyridyl)-2-(2-chloropropionylamino)-1,3,4-oxadiazole(5),5-(2-amino-3-pyridyl)-2-(3-chloropropionylamino)-1,3,4-oxadiazole (6) and 5-(2-amino-3-pyridyl)-2-(4-chlorobutyrylamino)-1,3,4-oxadiazole (7), respectively. Cyclization of chloroacyl derivative 7 led to 5-(2-amino-3-pyridyl)-2-(2-oxo-1-pyrrolidinyl)-1,3,4-oxadiazole (9). Treatment of oxadiazole 2 with appropriate alkylating agents (1,3-dibromopropane or 1,4-dibromobutane) gave 2-azetidinyl-1,3,4-oxadiazole (10) or 2-pyrrolidinyl-1,3,4-oxadiazole (11). Compounds 3, 4, 7, 10 and 11 were tested towards a psychotropic activity. Compound 10 showed anxiolytic properties and an antiserotonin action, which was confirmed in the test of the black-white box and the m-CPP test, respectively. Crystal structure was determined on a single crystal.

Olean-12-en-, 11-oxoolean-12-en-, and 12-oxoolean[3,2-b]quinoline-28-oic acid methyl esters (3a-3c) were obtained from the respective 3-oxoderivatives 1a-1c through the C(2) o-nitrobenzylidene derivatives 2a-2c. It was observed that the C(3) carbonyl group had an activating effect on the neighbouring methylene function and the C(2) and C(12) carbonyl group in some derivatives of methyl oleanolate were deprived of this property.

An effective method of computing kinetic parameters (n, , E_d) of thermal desorption from the experimental thermal desorption curve has been elaborated. So far the Downhill Simplex Method in Multidimensions for minimization and the Runge-Kutta method for solvation the Polanyi-Wigner equation, for any set of kinetic parameters proposed by the Simplex Method, have been applied. The fitting procedure is demonstrated on examples of low coverage thermal desorption spectra for H (D) adsorbed on a thin gold film surface at 78 K.

Basing on the Tchen equation, the dynamic characteristics of a system consisted of a little sphere moving in an oscillatory flowing gas are developed. The conditions of appearance of steady points of solutions (node, focus, saddle) are formulated. Numerical solutions show that an additional attractor (asymptotic trajectory) can be found in this system.

Inhibition of jack bean urease by a mixture of boric acid and phosphate buffer pH 6.96 was studied. The inhibition constants of the mixture were determined in solutions of phosphate buffer (22-155 mM) by measuring the initial reaction rates for a series of boric acid concentrations (0-3 mM) at a series of substrate concentrations (2-50 mM urea). It was found that boric acid is a simple competitive inhibitor of urease with the inhibition constant of the system changing from 0.23 mM in 22 mM phosphate buffer to 0.76 mM in 155 mM phosphate buffer. It was shown, that boric acid and phosphate buffer pH 6.96 are mutually exclusive competitive inhibitors of jack bean urease. The inhibition constants of boric acid and of phosphate buffer pH 6.96 in an inhibitor-free system were determined to be 0.12 mM and 21 mM, respectively.

The molecular structure of 8 and 9 has been determined by a single-crystal X-ray analysis. Both chiral esters are derivatives of the non-steroidal antiinflammatory drug diclofenac (1), and have physicochemical properties of potential prodrug. Comparison of the geometry of 2-[(2,6-dichlorophenyl)amino]phenylacetate fragment, observed in eighteen solid-state structures, shows limited flexibility of 1. Two rotations around bonds linking the o-phenyl ring with the carboxyl and dichlorophenyl groups change their relative orientation, but both groups are nearly perpendicular to the o-phenyl plane. The amino group is involved exclusively in intramolecular contacts.

N2-[4-(2-chlorophenyl)-1,3-thiazol-2-yl]-(1R,1S)-6,7-dimethoxy-1-(3-pyridylmethyl)-
1,2,3,4-tetrahydro-2-isoquinolinecarboxo amide (C₂₇H₂₅ClN₄O₃S) combines the aminothiazole fragment with the isoquinoline segment of known pharmacological activity. Conformation of a substituent at N2 of isoquinoline is determined by attractive Coulombic interaction between carbonyl oxygen and thiazole sulphur atom.