Crystal and Molecular Structure of Chelidonine

The crystal and molecular structure of benzophenantridine alkaloid chelidonine, C20H19N05 CM = 353.37) was solved by direct methods and refined by the least-squares technique to a conventional R index of 0.117 for 1888 unique reflections. The crystals are monoclinic, space group P21. Both, B and C rings have half chair conformation and are in cis junction. The N-methyl and C14-hydroxyl groups are in equatorial and axial positions, respectively. The OH-group forms intramolecular hydrogen bond with N atom. Conformation of the molecule is quite different from that found in chelidonine-p-brombenzoateCBB)

Magnetic Properties of Cr(III) and Fe(III) Ions in Hexaaqua-Nitrate-Trihydrates

The manuscript contains new measurements and calculations of magnetic susceptibility of Cr(III) and Fe(III) ions in hexaaqua-nitrate-trihydrate. The magnetic properties of the ion M=Cr(III), Fe(III) in hexaaqua-nitrate-trihydrate M(H2O)6(NO3)3·3H2O were studied from the temperature dependence of magnetic susceptibility determined using the SQUID susceptometer, within the temperature range 4 K ≤ T ≤ 290 K. The detected deviation from the CurieWeiss law is explained by the splitting of the ground state energies of the magnetic ions under the influence of the crystalline field (splitting in the zero field) and the contribution of the temperature independent Van-Vleck paramagnetism

Kristalna i molekulska struktura fotodegradacionog proizvoda nizoldipina

Potential and generally selective antihypertensive and antianginal activities of nisoldipine have initiated the study of its molecular structure. The single crystals, which are the potential photodegradation products, were crystallized from methanol solution of nisoldipine, which was exposed to the action of the daylight. They were assumed to be the nitrozo derivatives of nisoldipine with the melting point 151-152°C. The crystal and molecular structure was determined by the X-ray diffraction method (MoKα, λ=0.71073A). On the basis of 3858 independent reflection intensities, the structure was solved by the direct method using the program SHELXS83 and refined by the least squares method (SHELXL93) up to final R-factor R=0.0578 for 1953 reflection (F0>4σ(F0)) and 334 parameters. The molecular structure obtained was that of: isobutyl methyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydro pyridine -3,5 dicarboxylate which confirmed that we are dealing with nisoldipine, so one should not speak about the presence of any assumed photodegradation product. .Potencijalna i u opštem slučaju selektivna antihipertenzivna i antianginozna aktivnost nizoldipina kao i njegova izuzetna fotosenzitivnost na dnevnom svetlu, inicirala je istraživanje njegove molekulske strukture kao i molekulske strukture njegovih produkata. Iz metanolnog rastvora nizoldipina izloženog dejstvu dnevne svetlosti dobijeni su kristalizacijom potencijalni produkti fotodegradacije. Pretpostavljeno je da se radi o nitrozo derivatu nizoldipina, tačke topljenja 151-152°C. Kristalna i molekulska struktura određena je metodom difrakcije rendgenskih zraka (MoKα, λ=0.71073A). Na osnovu 3858 izmerenih intenziteta refleksa rešena je molekulska struktura, direktnom metodom primenom programa SHELXS83 i utačnjena metodom najmanjih kvadrata (SHELXL93) do konačnog R-faktora R=0.0578 za 1953 refleksa (F0>4σ(F0)) i 334 parametra. Dobijena molekulska struktura: izobutil metil-2,6-dimetil-4-(2-nitrofenil)-1,4-dihidropiridin-3,5-dikarboksilat, potvrdila je da se radi o nizoldipinu i da nema osnova govoriti da kristali pripadaju nekom od pretpostavljenih produkata fotodegradacije.

In situ XRPD and DSC study of order-disorder phase transition in nanosize Li-ferrite

An order-disorder phase transition of nanosize Li-ferrite (Li0.50Fe2.50O4) was studied by DSC measurements and in situ XRPD technique. The phase transition temperature is found to be 762 °C (DSC) and (745±5) °C (XRPD).Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200

Influence of the weak interaction on the structure of metallocycle in binuclear copper(II) complex

The structure of binuclear Cu(II) complex containing double oximato bridges was determined by the single-crystal X-ray diffraction analysis. Copper is five-coordinated with perchlorato anion present at the borderline of semi-coordination. Comparison with the structurally related diiminedioxime Cu(II) complexes revealed the influence of the weak Cu···O(perchlorate) interaction on the geometry of the metallocycle

The Crystal and Molecular Structure of 5α-Cholestane-3,6-dione

The crystals of 5a-cholestane-3,6-dione (C27H44O2) are monoclinic, space group P2i with a= 1.9695(3), 6-0.7593(3), c = 0.8176(6) run, /?=92.78(3)°, V= 1.221(1) nm3 and Z=2. The structure was solved by the direct method and refined by the least squares technique to a conventional R = 0.097 for 2220 unique diffractometer observations. Ring D assumed an envelope shape. The side chain equatorially attached to C17 assumed open »zig-zag« conformation

Dielectric Properties of Nanosized ZnFe2O4

In this paper we present the results concerning the dielectric properties of the nanosized ZnFe2O4. Dielectric permittivity, the loss factor, as well as the conductivity, were measured in the temperature range 300-630 K and at 1 Hz, 10 Hz, 100 Hz, 1 kHz and 10 kHz frequencies. Signifi cant improvements in permittivity, loss factor and ionic conductivity comparing to bulk samples have been observed

SYNTHESIS, X-RAY AND ANTIMICROBIAL ACTIVITY OF ISATIN-3-PHENYLHYDRAZONE

Isatin-3-phenylhydrazone was synthesized and X-ray crystal structure of this compound has been solved. Its structure was also established using FTIR, UV/Vis and 1H-NMR spectroscopic method. The compound was tested for antimicrobial activity against Staphylococcus aureus, Bacillus subtilus, Enterococcus D, Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa and Candida albicans. Stability of isatin-3-phenylhydrazone toward UV-A irradiation has been studied in this work. Isatin derivative undergoes bleaching following first-order kinetics

Crystal and Molecular Structure of Chelidonine

The crystal and molecular structure of benzophenantridine alkaloid chelidonine, C20H19N05 CM = 353.37) was solved by direct methods and refined by the least-squares technique to a conventional R index of 0.117 for 1888 unique reflections. The crystals are monoclinic, space group P21. Both, B and C rings have half chair conformation and are in cis junction. The N-methyl and C14-hydroxyl groups are in equatorial and axial positions, respectively. The OH-group forms intramolecular hydrogen bond with N atom. Conformation of the molecule is quite different from that found in chelidonine-p-brombenzoateCBB)

Antioxidative enzyme activities in wheat genotypes

Activities of superoxide dismutase (SOD), guaiacol peroxidase (PX), glutahione peroxidase (GPX) and catalase (CAT) as well as formation of malondialdehyde (MDA) and liposoluble fluorescent compounds (LFC) in leaves of 20 wheat genotypes, parents and hybrids of F1 and F2 generation were examined. The aim was to determine inheriting pattern of investigated parameters and relation between antioxidative enzyme activities and lipid peroxidation and LFC formation. No consistent role of inheritance of antioxidant parameters was found. Investigated genotypes and hybrids, among themselves, differed significantly in antioxidative enzyme activities and MDA and LFC content. Results presented indicate that high contents of MDA and LFC are associated with low activities of antioxidative enzymes. Also, relatively small quantities of MDA and LFC are associated with high activities of SOD and CAT