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Reactions of chiral nopinane-annulated diazafluorenone with substituted phenols and naphthols by the action of trifluoromethanesulfonic acid led to spiro products. The structure of the resorcinol derivative was confirmed by X-ray structural analysis.

Background: One of the future applications of magnetic nanoparticles is the development of new iron-oxide-based magnetic resonance imaging (MRI) negative contrast agents, which are intended to improve the results of diagnostics and complement existing Gd-based contrast media.Results: Iron oxide nanoparticles designed for use as MRI contrast media are precisely examined by a variety of methods: powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, Mössbauer spectroscopy and zero-field nuclear magnetic resonance (ZF-NMR) spectroscopy. TEM and XRD measurements reveal a spherical shape of the nanoparticles with an average diameter of 5–8 nm and a cubic spinel-type crystal structure of space group Fd−3m. Raman, Mössbauer and NMR spectroscopy clearly indicate the presence of the maghemite γ-Fe2O3 phase. Moreover, a difference in the magnetic behavior of uncoated and human serum albumin coated iron oxide nanoparticles was observed by Mössbauer spectroscopy.Conclusion: This difference in magnetic behavior is explained by the influence of biofunctionalization on the magnetic and electronic properties of the iron oxide nanoparticles. The ZF-NMR spectra analysis allowed us to determine the relative amount of iron located in the core and the surface layer of the nanoparticles. The obtained results are important for understanding the structural and magnetic properties of iron oxide nanoparticles used as T2 contrast agents for MRI.

Complexes [Zn(L2)2Cl2], [Pd2(L2)2Cl4], and CuL2Cl, where L2 is (−)-camphor thiosemicarbazone, were synthesized. The structures of complexes [Zn(L2)2Cl2] and [Pd2(L2)2Cl4] were determined by X-ray diffraction. The crystal structure of complex [Zn(L2)2Cl2] contains mononuclear molecules with distorted tetrahedral {ZnCl2S2} coordination units and monodentate L2 ligands. Complex [Pd2(L2)2Cl4] has binuclear structure with Pd metal centers linked by L2 ligands via μ2-S atoms. Complex CuL2Cl, according to IR and NMR spectra contains S and Cl atoms in the coordination sphere of ion Cu+. Complexes [Pd(tsc)Cl2] and Zn(tsc)2Cl2 (where tsc is thiosemicarbazide) were also obtained to determine the influence of the terpene moiety on cytotoxic properties of these compounds. Mononuclear complex [Pd(tsc)Cl2] contains an NSCl2 planar square coordination polyhedron, and tsc is a bidentate chelate ligand. The effects of tsc, L2, and the complexes with tsc and L2 on viability of the MCF-7 cell line were investigated next. The results showed that tsc and L2 are nontoxic at the tested concentrations (1–50 μM). All the complexes exerted a significant dose-dependent cytotoxic effect, whereas complex CuL2Cl was found to have the lowest half-maximal inhibitory concentration (IC50).

Mononuclear zinc(ii) and cadmium(ii) complexes, ZnLCl2 (1), CdLCl2 (2), ZnL1Cl2·2H2O (3), and CdL1Cl2·2H2O (4), with chiral ligands containing a 2,2'-bipyridine moiety and natural terpene (+)-limonene (L) or (+)-3-carene (L1) moieties were synthesized. In these complexes the L and L1 ligands are shown to coordinate Zn2+ and Cd2+ ions through the 2,2'-bipyridine moiety. The acetamide group of the ligands interacts with M2+ ions by forming NM2+ and C[double bond, length as m-dash]OM2+ contacts and N-HCl hydrogen bonds with coordinated Cl- ions. In solutions the complexes have several conformers differing by the degree of the turn of the acetamide moiety relative to the ligand core and the type of its interaction with the coordination core. The ligands and complexes exhibit luminescence with the quantum yield increasing in the order: ligandcadmium(ii) complexzinc(ii) complex. The complexes 3 and 4 demostrate excitation wavelength independent single-channel fluorescence. As opposed to 3 and 4, the complexes 1 and 2 demonstrate excitation wavelength dependent emission with nanosecond and microsecond lifetimes of the excited states. According to our TD-DFT calculations, an interplay of ligand centered and halide to ligand transitions facilitates two deactivation channels in 1 and 2: S1-S0 and T1-S0.

Reaction of fused 4,5-diazafluorene–bis(nopinane) with tere-phthalaldehyde, benzophenone, ninhydrin or anthraquinone in THF in the presence of TiCl4 and pyridine results in a formation of new chiral condensation products, which exhibit solvatochromism and pleochroism. Crystal structure of the key products has been determined by X-ray crystallography, and unusual colour behavior has been explained by DFT calculations.

Three salts of perchlorinated sulfonium and ammonium derivatives of tetrabuthylammonium nonachloro-closo-decaborate, (n-Bu4N)2[2-B10Cl9-cyclo-S(CH2)4S-B10Cl9] (1), (n-Bu4N)[2-B10Cl9-cyclo-S(C2H4)2O] (2) and (n-Bu4N)[1-B10Cl9N(n-Pr3)] (3) are synthesized and characterized using IR, 11B, 1H, 13C NMR, X-Ray and 35Cl NQR-spectroscopy. The noncovalent interactions involving chlorine atoms were identified by 35Cl NQR spectra. The results were discussed in comparison with those of X-ray diffraction analysis which are based on measuring contacts shorter than the sum of van der Waals (vdW) radii of atoms. It has been found that the crystal lattice of 2 exhibits dynamic properties strongly different from those of 1 and 3. Whereas the 35Cl NQR spectra of the latters were extremely wide (up to 1200 kHz), the spectrum of 2 demonstrated a narrowing of almost an order of magnitude (up to 120 kHz) which indicated a significant weakening of the tendency for the formation of intermolecular bonds by chlorine atoms of this cluster.

A series of lanthanide(iii) complexes based on the new chiral ligand L, which contains 1,10-phenanthroline and (-)-menthol fragments, namely [LnL2(NO3)3] (Ln = Eu (1), Gd (2), Tb (3), Dy (4)), have been synthesized and structurally characterized. Complexes 1-4 are isostructural and crystallize in the non-centrosymmetric space group P41212. The mononuclear complexes comprise a 10-coordinate Ln3+ ion with two bidentate N,N-donor ligands (L) and three bidentate chelating nitrate groups. The magnetic properties of complexes 1-4 are determined mainly by the Ln3+ ions. In the case of complexes 3 and 4, significant anisotropy results in nonlinear field dependences of magnetization at low temperature. Complexes 1, 3 and 4 exhibit metal-centered red (Eu3+), green (Tb3+) and yellow (Dy3+) luminescence, respectively, whereas complex 2 displays blue ligand-based luminescence in the solid state at room temperature. The luminescence quantum yield for the solid samples increases in the order 4 < 2 ≈ 3 < 1. The europium(iii) complex shows long luminescence lifetimes (up to 1750 μs) and a very high quantum yield (φf = 0.87); these make this compound promising for application in sensing and optoelectronics.

Mononuclear and dinuclear zinc(II) and cadmium(II) complexes, [ZnLCl2] (1) and [Cd2L2Cl4] (2), with a chiral pentacyclic dihydrophenanthroline ligand L bearing a natural monoterpene (–)-α-pinene fragment were synthesized. DFT calculations of the specific rotation [α] and an NMR study show that the molecules of ligand L, complex 1 and the monomeric form of complex 2 exist in CDCl3 solutions with the P-helix conformation for the dihydrophenanthroline moiety. The dihydrophenanthroline fragments of L and mononuclear complex 1 also exists as a P-helix in the solid state, whereas the crystalline dinuclear complex 2 exists as an asymmetric dimer, [Cd2Cl4LPLM], where LP and LM are the ligand with P-helix and M-helix conformations of the dihydrophenanthroline fragment respectively. Full sets of photophysical parameters for L and complexes 1 and 2 have been determined. Compounds L, 1 and 2 display blue luminescence (λmax = 427, 405 and 415 nm in the solid state, respectively). The ligand L and complex 2 show moderate-to high quantum yields of 44% and 24%, respectively. The quantum yield for complex 1 is 6%. The emission lifetimes increase on going along the spectrum of luminescence, and in the deep red region, a rise of luminescence with times of 200–500 ps is observed. These processes can be explained by the migration of excitons and the capture of excitation by “defective” centers.

In this paper we present study of the magnetic structure of multiferroic series Bi1-yLayFeO3 (y = 0, 0.015, 0.03, 0.05 and 0.10) using nuclear magnetic resonance (NMR) at 4.2 K and Mossbauer spectroscopy at room temperature on 57Fe nuclei. We observed the presence of cycloid type spatial spin-modulated structure (SSMS) in the whole range of compositions. The study of the concentration dependence of the anharmonicity parameter m revealed that at the temperature of liquid helium in the composition region y = 0 – 0.10 as well as at room temperature for y = 0.03 the magnetic state of multiferroics is described by cycloid type SSMS with a positive effective uniaxial constant of magnetic anisotropy Κu > 0 (“easy axis” model). The study at room temperature in turn revealed that magnetic state of the multiferroics with y = 0 – 0.03 is described by cycloid type SSMS with a positive effective uniaxial constant of magnetic anisotropy Κu > 0 (“easy axis” model). In contrast, the magnetic state of multiferroics with y = 0.05 and 0.10 is described by a negative effective uniaxial constant of magnetic anisotropy Κu

Reaction of (+)-pinocarvone oxime with 2-morpholinocyclopent-2-enone and FeCl3·6H2O affords chiral C2-symmetric fused derivative of 4,5-diazafluorene, whose oxidation with SeO2 gives nopinane-annelated derivatives of 4,5-diaza-9Hfluoren- 9-one (C2-symmetry) and of 9,9’-bi-4,5-diazafluorenylidene (D2-symmetry). Structures of the compounds synthesized were proved by X-ray crystallography.

The complexes [Cu(HL)Cl] · 0.25H2O (I), [Cu(HL1)Cl] · 0.5H2O (II), [Ag(HL)] · 0.5H2O (III) were obtained; HL– and (HL1)– are the anions of the chiral N-substituted aminoacetic acid derivatives containing the natural monoterpenes (+)-3-carene and (–)-α-pinene, respectively. The µeff values for paramagnetic complexes I and II are 1.92 and 1.81 µB, respectively. Single crystals of the coordination 1D polymer [Cu(HL)Cl · 2H2O]n (IV) were grown. According to the X-ray diffraction data (CIF file CCDC No. 1035219), the crystal structure of complex IV is made up of the zigzag chains [Cu(HL)Cl]n and water molecules. The coordination polyhedron of the Cu atom is a distorted square pyramid (ClN2O2). The anion HL– acts as a chelating and bridging tetradentate ligand coordinated through the N atoms of the NH and NOH groups as well as through the O atoms of the COO–groups linking two adjacent Cu atoms together. The IR spectra of complexes I and II also provide evidence for the coordination of the functional COO–, NOH, and NH groups. In complex III, the coordination sphere of the Ag atom is made up of the O atoms of the COO–group. Complex III shows weak green photoluminescence (λmax = 530 nm).

The [ZnLCl2] (1) and Cd2L2Cl4 (2) complexes, where L is ethyl 2-methyl-5-(prop-1-en-2-yl)pyrido[2,3-a]phenazine-3-carboxylate, were synthesized. The complexes were characterized by elemental analyses, 1H and 13C NMR spectroscopy, and X-ray powder diffraction. Single crystals of 1 and [Cd2L2Cl4]·4CH2Cl2 (3) have been grown. The structure of 1 consists of mononuclear molecules, while the structure of 3 is built up of centrosymmetrical binuclear [Cd2L2Cl4] complex molecules and uncoordinated CH2Cl2 molecules. In 1 and 3, L acts as a bidentate chelating ligand. There is five-membered ZnN2C2 chelate cycle in the [ZnLCl2] molecule. There are two five-membered CdN2C2 chelate cycles and a Cd2Cl2 dinuclear unit in the molecule of [Cd2L2Cl4]. The coordination polyhedra are distorted tetrahedron Cl2N2 (in the structure 1) and distorted tetragonal pyramid Cl3N2 (in the structure of 3). According to IR-spectroscopic data, complex 2 is binuclear. Complexes 1 and 2 display bright luminescence in CHCl3 solutions (λmax = 477 and 475 nm, respectively) and in the solid state (λmax = 510 and 529 nm, respectively). The free L ligand shows weak luminescence intensity (λmax = 441 and 467 nm in CHCl3 and solid state, respectively).

Reaction of pinocarvone oxime with enamines and FeCl3 or CuCl2 resulted in annulation of nopinane carbon frame with pyridine and regioselective formation of chiral nopinane-annelated pyridines in 20–39% yields. Chemical structure of the pyridine derivatives were proved by precise NMR study.

A synthetic approach to a new group of stable chiral C2-symmetric diimines with the 4,5-diazafluorene core has been developed based on condensation of dipinodiazafluorene with aromatic diamines. The chemical structures of new compounds were proven by spectroscopic methods and X-ray crystallography. All the compounds form solvates with organic solvents (chloroform, benzene, 1,4-dioxane) and water. Specific spectral data of the new compounds are explained using calculated data (DFT). Diimines of the pinodiazafluorene series give colored reactions with transition metal ions and can be regarded as prospective polydentate ligands with interesting luminescent and chiroptical properties.

(+)-3-Carene-, (S)-(–)-α-pinene- and (R)-(+)-limonene-derived α-nitroso chlorides on treatment with an excess of acetone cyanohydrin afford the corresponding α-cyano oximes, whose structure was solved by X-ray crystallography.

The optically active complexes [Zn(L)2Cl2] (I) and [Zn(L1)2Cl2] (II) (L and L1 are thiosemicar-bazones of (+)-camphor and (−)-carvone, respectively) were obtained. The crystal structures of L and complex I were determined by X-ray diffraction. The structure of L consists of hydrogen-bonded molecules united into chains. The crystal structure of complex I is built from mononuclear molecules. The coordination polyhedron of the Zn atom is a distorted tetrahedron Cl2S2. The molecule L functions as a monodentate ligand. According to data from IR spectroscopy, complex II is structurally similar to complex I.

The complex of CdCl2 with 2-(3,5-dimethylpyrazol-1-yl)-4-methylquinoline (L), Cd2(L)Cl4 (I), is synthesized. According to the X-ray diffraction data, the structure of coordination polymer I is formed by chains in which two crystallographically independent Cd atoms linked by the bridging Cl atoms have different coordination numbers (5 and 6) and different environments. Five Cl atoms form the coordination polyhedron of the Cd(2) atom: a square pyramid (Cd-Cl 2.554(3)–2.689(3) A) completed to a bipyramid by the CI atom at a substantially longer distance of 2.865(4) A. Two Cl atoms and the N atom of quinoline fragment L are arranged in the equatorial plane of the coordination polyhedron of the Cd(1) atom, which is a distorted trigonal bipyramid. The axial vertices are occupied by the N atom of the pyrazole cycle of L and the Cl atom. Five-membered metallocycles CdCN3 are formed upon the coordination of bidentate chelating ligands L. The planes of L of two adjacent chains are parallel (the distances between them are ∼3.5 A), which suggests the π-π interaction between the planes. The luminescence excitation spectrum of compound I has a broad band with λmax = 350 nm. The spectrum of bright blue photoluminescence of compound I (300 K, λexc = 340 nm) contains an intense band with λmax = 420 nm.

Coordination compounds Cu2(H2L1)Cl4 (I), Pd2(H2L1)Cl4 (II), Cu2(H2L2)Cl4 (III), and Pd2(H2L2) Cl4 (IV) with chiral bis-α-sulfanyloximes, the derivatives of the monoterpenoid (−)-α-pinene, were obtained. The complexes I and III are paramagnetic (μeff = 2.45 and 2.67 μB, respectively), II and IV are diamagnetic. According to IR spectroscopy, in the compounds I–IV the nearest environment of Cu and Pd atoms includes N, S, and Cl atoms. The values of μeff and parameters of ESR spectra of the solid phase and solutions of I and III show a binuclear structure of the Cu(II) complexes. Parameters of the 1H and 13C NMR spectra of compounds II and IV indicate the formation of binuclear Pd(II) complexes of C2 symmetry and the closure of fivemembered chelate rings PdNSC2. The PdCl2 fragments are in transoid position. H2L1 and H2L2 are tetradentate bridging chelating ligands.

The Cu2LCl4 complex (I) with chiral bis{(E)-[(1S,4R)-Δ7,8-1-amino-2-para-menthalidene]aminohydroxy} methane (L — a derivative of natural monoterpenoid (R)-(+)-limonene) is synthesized. The crystal structure of the solvate of complex I[Cu(L)(μ-Cl)CuCl3] · iso-PrOH (II) is determined by X-ray diffraction analysis. Structure II is based on molecules of the [Cu(L)(μ-Cl)CuCl3] binuclear complexes in which L is the tetradentate cycleforming ligand. One Cl atom manifests the bridging function. The CuN4 Cl coordination unit is a square pyramid, and CuCl4 is a distorted tetrahedron. The iso-PrOH molecules are localized in cavities between the layers of structure II. The μeff value for complex I is 2.56 μB and indicates the absence of an appreciable interaction between the Cu2+ ions in the Cu(II)-Cl-Cu(II) exchange cluster. The compound CuLCl2· H2O (III) is synthesized. The μeff value for compound III is 1.6 μB. Complexes I and III are studied by EPR and IR spectroscopy.

The NMR technique has been applied to characterize the phototransformation products of the natural alkaloid lappaconitine. It was demonstrated that the photolysis of lappaconitine 1 results in cleavage of the ester bond with elimination of N-acetylanthranilic acid. The final reaction product was found to be an immonium salt 4 of N-acetylanthranilic acid and enamine 3. An equilibrium between the imine cation and the enamine 3 was detected.

The reaction of 1R,2R,5R-2-dimethylamino-2,6,6-trimethylbicyclo[3.1.1]heptane-3-one oxime (pinaneoxime) with Os3(CO)10(NCMe)2 was used to synthesize the (μ-H)Os3(μ-κ1-O-N=C12H21N)(CO)10 cluster with coordination of the ligand through the oxime O atom and invariable terpenoid structure. The structure of the synthesized cluster was determined by X-ray diffraction analysis. The theoretical conformational analysis of the above cluster in a solution and in crystal state was performed by a combined MM3/MERA method. The rotation of a ligand about the O(1)-N(2) bond was found impossible due to a high energy barrier (E > 550 kJ/mol).

Chiral bis-α-thiooxime (H2L1), the derivative of the natural monoterpenoid (+)-3-carene, was synthesized and used to prepare paramagnetic complexes of the composition M(H2L1)Cl2 (M=Ni, Cu). The crystal structures of [Ni(H2L1)Cl2] (I) and [Cu(H2L1)Cl2] (II) were determined by X-ray diffraction analysis. Crystals I and II consist of mononuclear acentric molecules. The Ni2+ ion in a molecule of complex I coordinates two N atoms and two S atoms of a tetradentate chelating ligand (the H2L1 molecule) and two Cl atoms. The NiCl2N2S2 coordination core forms octahedron compressed along the apical N atoms. In a molecule of complex II, the Cu2+ ion coordinates two S atoms and the N atom of a tridentate chelating H2L1 ligand and two Cl atoms. The CuCl2NS2 coordination core forms a trigonal bipyramid.

A three component condensation of 6-quinolylamine with 4-bromo-or 4-methoxybenzaldehyde, and 1,3-cyclohexanedione or dimedone gave 12-(4-bromophenyl)-and 12-(4-methoxyphenyl)-9,9-dimethyl-8,9,10,12-tetrahydro-7H-benzo[b][4,7]phenanthrolin-11-ones. The reaction intermediates obtained were N-arylmethylene-6-quinolylamines, 2-arylmethylenebis(1,3-cyclohexanediones), 3-(6-quinolylamino)-2-cyclohexenone, and 5,5-dimethyl-3-(6-quinolylamino)-2-cyclohexenone.

Coordination compounds [CoLCl2] (I), [CuLCl(NO3)] (II), CuL(NO3)2 (III), and CuLCl2 (IV) (where L is a chiral pyrazolylquinoline—a derivative of terpenoid (+)-3-carene) were synthesized. X-ray diffraction data showed that crystal structures I and II are built of mononuclear acentric molecules. In the molecule of complex I, the Co2+ ion coordinates two N atoms of bidentate cycle-forming ligand L and two Cl atoms. The coordination polyhedron of Cl2N2 is a distorted tetrahedron. For complex I, μeff = 4.50 μB, which corresponds to a high-spin configuration d 7. In the molecules of II(1), II(2) (which are diastereoisomers of complex II), each Cu2+ ion coordinates two N atoms of bidentate cycle-forming ligand L, the Cl atom, and two O atoms of bidentate cyclic NO 3 − ion. The ClN2O2 coordination polyhedra are tetragonal pyramids with different degrees of distortion. The structure of complex II consists of supramolecular clusters, i.e., isolated chains incorporating the molecules of II(1) and II(2). The values of μeff for II–IV correspond to the d 9 configuration. The results of EPR and IR study suggest that complex III contains the O4N2 polyhedron, whereas complex IV contains the Cl2N2 polyhedron. Complexes I and IV were found to show a high catalytic activity in ethylene polymerization reaction.

The copper(II) compounds [CuL](NO3)2 · H2O (I), [CuL](ClO4)2 · H2O (II), CuLCl2 · 3H2O (III), and CuLBr2 · 4H2O (IV), where L is a chiral dioxatetraazamacrocyclic ligand based on the natural monoterpene (+)-3-carene, have been synthesized. According to IR and EPR spectroscopy, L acts as a tetradentate chelating ligand coordinated through the N atoms of the NH and C=N groups. The NO 3 − anions in I and the ClO 4 − anions in II are outer-sphere. I and II have a planar coordination core CuN4, III has a CuN4ClO coordination core, and IV has a CuN4Br2 coordination core.

The synthesis of the [Cu(H2L)](NO3)2 complex (I) and of a mixed-valent complex [Cu(H2L)Cl]2[CuCl2]Cl·0.5H2O (II), where L is chiral bis(menthane) propylenediaminodioxime. According to the data of single-crystal X-ray diffraction analysis, compounds I and II have ionic structures. In complex cations, the Cu2+ ion coordinates four N atoms of tetradentate chelate ligand, namely, the H2L molecule. The coordination surrounding of the Cu atom in I is a distorted square CuN4, while in II, it is a distorted square pyramid CuN4Cl. The complex anion [CuCl2]− in II has linear structure. The mutual arrangement of oxime groups in H2L corresponds to amphi-configuration of a ligand and therefore, intramolecular hydrogen bond O...H-O are formed in H2L. The complex cations in compound II are joined in dimers through hydrogen bonds Cl...H-O. The values μeff for I and II are equal to 1.82 and 2.82 μB, respectively.

Copper(II) complexes with chiral ethylenediaminodioxime (H2L1) and propylenediaminodioxime (H2L2), the derivatives of terpenoid α-pinene, of the composition [Cu(H2L1)](NO3)2 (I) and [Cu(H2L2)NO3]NO3 (II) are synthesized and studied by X-ray diffraction method. The ionic structures of I and II consist of complex cations [Cu(H2L1)]2+ (I), [Cu(H2L2)NO3]+ (II), and outer-sphere anions NO 3 − . In the cation of compound I, the Cu2+ ion (C.N.4) coordinates four N atoms of tetradentate cycle-forming ligand H2L1 with anti-configuration. The coordination surrounding of the Cu atom is a trapezoidally distorted square. In the cation of compound II, the Cu2+ ion (C.N.5) coordinates the O atom of monodentate nitro group in addition to four N atoms of tetradentate cycle-forming ligand H2L2. The coordination polyhedron of the Cu atom has the shape of a distorted square pyramid N4O. Coordinated H2L2 molecule has amphi-configuration, which is responsible for the formation of hydrogen bond between the oxime groups. The complex cations and NO 3 − anions in structures I and II are linked into ionic ensembles by hydrogen bonds.

Distillation of the flowering tops of Seseli buchtormense (Fisch. ex Sprengel) W. Koch obtained from various altitudes of Altai Region yielded 0.21% (300 m.a.s.l.), 32% (400 m.a.s.l.), 30% (700 m.a.s.l.) and 0.40% (2030 m.a.s.l.), of aromatic pure mobile oil. Analysis of the oil samples using GC, GC/MS gave 82 components. The major components were sabinene (17.7–25.1%), α-pinene (5.3–14.6%), (E)-nerolidole (5.5–11.6%), β-phelandrene (2.5–7.0%), β-myrcene (3.3–6.6%), δ-kadinene (3.0–6.0%), germacrene D-4-ol (3.1–4.6%), α-bosabolol (0.0–7.7%), fenchone (0.5–7.0%) and limonene (0.8–4.5%).

Distillation of the fresh flowering tops of wild-growing Solidago virgaurea L. collected from the Russian Altai at 290 m and 650 m yielded 0.22% and 0.07% pure light yellow oil, respectively. GC and GC/MS analyses of the oils revealed that the main components from 290 m were α-pinene (36.5%), myrcene (14.8%), β-caryophyllene (10.5%), germacrene D (8.2%), β-pinene (7.1%) and limonene+β-phellandrene (6.4%). The oil from the sample collected at 650 m had benzyl benzoate (57.0%), β-caryophyllene (6.3%), germacrene D (6.0%), α-pinene (4.4%) and α-humulene (4.0%) as major components, suggesting polymorphism or the existence of different chemoytpes. Using the disc diffusion method we tested the activity of the oil obtained from 290 m against five microbes of health and environmental importance. It showed complete inhibition or killed Aspergillus niger and Staphylococcus aureus, strong inhibition of Saccharomyces cervisiae, and low activity against Escherichia coli, but no effect on Pseudomonas aeruginosa.

Mannich condensation of 3,3,5-trimethylcyclohexanone with paraformaldehyde and dimethylamine or benzylamine hydrochloride involves both activated methylene group in the initial ketone to give compounds with equatorial aminomethyl substituent. The major isomer is that formed by addition at the less sterically hindered carbon atom. Likewise, Mannich condensation of the E and Z isomers of 3,3,5-trimethylcyclohexanone oxime react at both methylene groups, and the addition of aminomethyl fragment occurs preferentially at that methylene group which is located more closely to the oxime hydroxy group.

Reactions of (dichloroiodo)benzene or (dichloroiodo)benzene/iodine with various monoterpenes in methanol provide a selective approach to the respective products of chloromethoxylation or iodomethoxylation of the double bond. The halomethoxylation of (+)-3-carene, carvone, and β- pinene proceeds with especially high regio- and stereoselectivity affording an appropriate single product in each case, while the reaction of limonene gives products of functionalization of both double bonds. This new methodology for the controlled introduction of halogen substituents into the structure of naturally occuring monoterpenes provides an entry into various potentially important synthetic intermediates.

New optically active levorotatory compounds [Ni(HL1)]NO3 (I) and [Ni(HL2)]NO3· H2O (II) containing the anions of chiral diaminodioximes, H2L1 and H2L2, derived from the terpenes ±-pinene and (+)-3- carene, respectively, were synthesized. Complexes I and II were studied by X-ray diffraction. The crystal structures of compounds are ionic, being composed of the [Ni(HL1)]+ or [Ni(HL2)]+ cations and the outer-sphere NO−3 anions. The Ni2+ ion coordinates four N atoms of the tetradentate chelating ligand, the NiN4 coordination unit being shaped like a tetrahedrally distorted square. Compounds I and II are diamagnetic, which corresponds to a low-spin d8 configuration. The NMR spectra of compounds were recorded and analyzed.

Copper(II) compounds with the optically active diaminodioxime (H2L) derived from the monoterpenoid (+)-3-carene, Cu(H2L)(NO3)2·H2O (I), Cu(H2L)(ClO4)2·H2O (II), Cu(H2L)Br2·H2O (III), and Cu(H2L)SO4·0.5H2O (IV) with µeff equal to 1.81, 1.79, 1.71, and 1.8 µB, respectively, were prepared. Studies of the complexes by IR and EPR spectroscopy showed that I and II are mononuclear ionic complexes. Compound III apparently has polymeric structure (the CuN4Br2 coordination unit). According to EPR data, the Cu2+ ions in polycrystalline compounds III and IV undergo exchange interactions.

New coordination compounds of copper(I) have been synthesized: [Cu2L 2 1 Cl2] (I) and [Cu2(HL2)2Br2] (II), where L1 is methyl 3-[(3,5-dimethyl-pyrazole-1-carbothioyl)-amino]-propionate, and HL2 is ethyl [(3,5-dimethyl-pyrazole-1-carbothioyl)-amino]-acetate. X-ray diffraction analysis showed that the crystal structures of these compounds are built from binuclear molecules. The L1 and HL2 molecules perform the bridging tridentate cyclic function, which results in a closure of two five-membered chelate cycles CuN2SC and metallocycle Cu2S2. Each Cu atom coordinates the N atom of the pyrazole ring, the halogen atom (Cl in I and Br in II), and two S atoms, thus forming a distorted tetrahedron. The Cu2S2 metallocycles, the CuN2SC chelate cycles, and the pyrazole rings are flat. Both CuN2SC chelate cycles are almost perpendicular to the Cu2S2 metallocycle and form a chair conformation. Redox reactions in CuCl2·2H2O-L1-ethanol and CuBr2-HL2-ethanol systems were examined by EPR spectroscopy.

The reaction of acetone-4-(2-methoxy-phenyl)thiosemicarbazone with triosmium cluster Os3(CO)11(NCMe) results in the formation of the cluster with the μ2 chelate-bridging ligand coordinated by S and N1 atoms, which was studied by X-ray diffraction analysis. Reaction of (3aR, 3bR, 4aR, 5aS)-5a-hydroxy-3,4,4-trimethyl-3a,3b,4,4a,5,5a-hexahydrocyclopropa[3, 4]cyclopenta[1,2-c]pyrazole-1-carbothioic acid amide with Os3(CO)11(NCMe) gives rise to the complex with the bridging ligand coordinated by sulphur atom. Further transformation of the complex in hot benzene results in tautomeric rearrangement of the organic ligand and the cleavage of the pyrazolinol cycle to form an open chain tautomer. Unusual silica gel induced oxidative cleavage of the cyclopropane ring in the open chain derivative and epoxidation of cycloalcane C–C bond are observed on the air.

Condensation of dimethyl and diethyl acetylenedicarboxylate with thioacetamides gave the corresponding alkyl (3-oxo-2,3-dihydrothiophen-2-ylidene)- and (4-oxothiazolidin-5-ylidene)acetates. Treatment of these compounds with zinc in acetic acid resulted in reduction of the exocyclic double bonds. The products can be used in membrane processes as sodium cation carriers.

A method for the synthesis of previously inaccessible 5-dialkylamino-substituted 1,2,3-thiadiazole-4-carbaldehydes was developed. Ring transformation in these compounds induced by primary aliphatic and aromatic amines, hydroxylamines, and N-substituted hydrazines resulted in the synthesis of a broad range of 1,2,3-triazole-4-carbothioamide.

Paramagnetic complexes Cu(HL1)Cl2 (I), Cu(HL2)Cl2 · 2H2O (II), and Cu(HL1)Br2 (III) are synthesized by the reaction of copper(II) halides with the optically active α-alkylamino oximes HL1 and HL2 of caryophyllene type. Crystal and molecular structures of complex I are determined. The crystals are orthorhombic: a = 9.038(2) A, b = 11.990(2) A, c = 11.990(2) A, V = 2004.8(7) A3, space group P212121, Z = 4, ρ(calcd) = 1.812 g/cm3, R1 = 0.0632. In a mononuclear complex I, the coordination polyhedron of CuCl2N2 is a distorted square. The structures of complexes II and III are suggested on the basis of EPR, IR and Raman spectroscopy data.

Copper(II) complexes with (1R*,4S*)-1-N-morpholino-n-menth-8-en-4-one (HL), namely, [Cu2(HL)2Cl4] (I) and [Cu2(HL)LCl3] · CH3CN (II), were synthesized and characterized by X-ray diffraction analysis, magnetic susceptibility, and EPR methods. The complexes have binuclear structures. In compound I, the coordination polyhedron of CuCl3N2 is a square pyramid in planar Cu2Cl2 metal cycle; the exchange couplings of unpaired electrons of Cu(II) ions are weak. Complex II incorporates polyhedra of CuCl2N2 (flattened tetrahedron) and of CuCl2N2O (trigonal bipyramid). The Cu2ClNO metal cycle is nonplanar with antiferromagnetic exchange coupling and exchange parameter –2J = 182 cm–1. The EPR spectrum of compound I are analyzed.

Ni(II) chelate with (3S)-3-hydroxyaminocaran-4-one E-oxime (H2L) of composition Ni(HL)2 · 2H2O was synthesized. The compound is diamagnetic, which suggests the square-planar structure of a NiN4 coordination unit. The electronic absorption spectroscopy and EPR methods were used to study its oxidative dehydrogenation in benzene resulting in a compound containing nitroxyl radicals Ni(HL·)2 and exhibiting strong antiferromagnetic exchange coupling of unpaired electrons of the radicals. An intermediate paramagnetic form Ni(HL)(HL·) was discovered by the EPR method.

Reaction of 3-nitro- and 3-ethoxycarbonyl-1,2,4-triazolo[5,1-c]-1,2,4-triazin-4-ones with 1-adamantanol (or 1-adamantyl nitrate) in concentrated sulfuric acid or with 1-bromoadamantane in sulfolane affords N-adamantyl derivatives. The adamantylation of 3-nitro-1,4-dihydro-7H-1,2,4-triazolo[5,1-c]-1,2,4-triazin-4-one yields a mixture of N8- and N1-isomers that undergo interconversion in concentrated sulfuric acid along intermolecular mechanism.

2-(Alkoxycarbonylmethylidene)-4-aryl-5-(dialkylamino)thiophen-3(2H)-ones were synthesized by condensation of N,N-(dialkyl)arylthioacetamides with dialkyl acetylenedicarboxylates. Intermediate substituted vinylic sulfides were isolated. When heated or in the presence of an acid or a base, they undergo cyclization into thiophenes.

Depending on the conditions, 3-(4-R-thiosemicarbazido)-2-polyfluorobenzoylacrylates can be converted into the corresponding potassium salts, [1,3,4]thiadiazino[6,5,4-ij]quinolines, and pyrazole or 1,3,4-thiadiazole derivatives.

Benzylic oxidation of pinopyridine with SeO2 affords the corresponding keto derivative (71% yield) whose reductive amination with o- and p-anisidines proceeds stereoselectively to give 8R-amino derivatives; the reaction with o-phenylenediamine results in achiral pyridophenazine derivative possessing intense blue fluorescence at 441 nm. Structures of o-anisidine derivative and substituted pyridophenazine have been characterized by X-ray crystallography.

Reactions of chiral β-diketone with racemic hydrazines as well as reaction of chiral pyrazole with cyclohexene epoxide and trans-stilbene epoxide have been examined as the routes to optically active pyrazolylethanols. Diastereomerically pure products have been isolated by crystallization or column chromatography in good yields.

Hydrolysis of bis(2,2,2-trifluoroethyl) 2,2-dimethylcyclopropane-1,1-dicarboxylate with pig liver esterase afforded (1 R )-2,2-dimethyl-1-(2,2,2-trifluoroethoxycarbonyl)-cyclopropane-1-carboxylic acid in high enantiomeric excess. This compound was rearranged to (1 S )-2,2,2-trifluoroethyl-2,2-dimethyl-1-[( N -ethoxycarbonyl)amino]-cyclopropane-1-carboxylate via a Curtius type reaction with DPPA. Final alkaline hydrolysis gave (1 S )-1-amino-2,2-dimethylcyclopropane-1-carboxylic acid.