Jan Janczak

Crystal structure, vibrational spectra and nonlinear optical properties of tetrakis(2,4,6-triamino-1,3,5-triazin-1-ium) bis(selenate) trihydrate crystal

Abstract X-ray single crystal diffraction and the vibrational spectroscopic analysis of a new melaminium salt, tetrakis(2,4,6-triamino-1,3,5-triazin-1-ium) bis(selenate) trihydrate, (C3H7N6+)4·(SeO42−)2·3H2O, is reported. The compound crystallizes in the non centrosymmetric space group of triclinic system. Second harmonic generation efficiency deff=0.4deff(KDP). Intense hydrogen-bonded network is present in the crystal structure of the complex with notable vibrational effects.

Synthesis, cytotoxicity and antibacterial activity of new esters of polyether antibiotic – salinomycin

A series of 12 novel ester derivatives of naturally occurring polyether antibiotic - salinomycin were synthesized, characterised by spectroscopic method and evaluated for their in vitro antibacterial activity and cytotoxicity. The new esters were demonstrated to form complexes with monovalent and divalent metal cation of 1:1 stoichiometry in contrast to the salinomycin which forms only complexes with monovalent cations. All the obtained compounds show potent antiproliferative activity against human cancer cell lines and a good selectivity index for cancer versus mammalian cells. Additionally, 3 compounds showed higher antiproliferative activity against the drug-resistant cancer cells and lower toxicity towards normal cells than those of unmodified salinomycin and standard anticancer drugs such as cisplatin and doxorubicin. Some of the synthesized compounds showed good inhibitory activity against Staphylococcus strains and clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE). These studies show that salinomycin esters are interesting scaffolds for the development of novel anticancer and Gram-positive antibacterial agents.

Antiproliferative activity of salinomycin and its derivatives.

Antiproliferative activity of seven amides and one benzotriazole ester derivative of salinomycin, a polyether ionophore antibiotic, with recently reported antibacterial activity, are herein described. Salinomycin and the majority of derivatives exhibit potent antiproliferative activity against the drug-resistant cancer cell lines. Moreover almost all derivatives show stronger activity against LoVo/DX cell line than that of unmodified salinomycin.

X-ray analysis of phthalocyanines formed in the reaction of AuCu and AuSn alloys with 1,2-dicyanobenzene

Abstract X-ray investigations of the reactions of copper, tin and their alloys with gold, with 1,2-dicyanobenzene at 210 °C have been performed. It was found that under the conditions used, gold does not take part in the reaction with 1,2-dicyanobenzene, but separates from the alloys. Copper and tin phthalocyanines are formed as the main products of the above reactions. The crystal structure of tin phthalocyanine (SnPC) has been determined. SnPc crystallizes in the triclinic system ( a=12.048(3) A , b=12.630(3) A , c=8.671(3) A , a=95.85(5)°, β=95.10(5)°, γ=68.25(5)°), space group P 1 , Z=2. The refined structure with anisotropic temperature factors gave R=0.041. The Sn atom is coordinated by four isoindole N atoms, the average SnN distance being 2.267(6) A. The SnPc molecule is not planar. The Sn atom is 1.1286 A out of the plane of the four coordinating N atoms.

Synthesis and antimicrobial activity of amide derivatives of polyether antibiotic-salinomycin.

For the first time a direct and practical approach to the synthesis of eight amide derivatives of polyether antibiotic-salinomycin is described. The structure of allyl amide (3a) has been determined using X-ray diffraction. Salinomycin and its amide derivatives have been screened for their in vitro antimicrobial activity against the typical gram-positive cocci, gram-negative rods and yeast-like organisms, as well as against a series of clinical isolates of methicillin-resistant Staphylococcus aureus and methicillin-sensitive S. aureus. Amides of salinomycin have been found to show a wide range of activities, from inactive at 256 μg/mL to active with MIC of 2 μg/mL, comparable with salinomycin. As a result, phenyl amide (3b) was found to be the most active salinomycin derivative against gram-positive bacteria, MRSA and MSSA.

Synthesis, structural investigations and magnetic properties of dipyridinated manganese phthalocyanine, MnPc(py)2

Abstract The MnPc(py)2 complex was obtained in the reaction of MnPc with purified and dry pyridine under non-oxidation conditions. It crystallises in the centrosymmetric space group P21/c of the monoclinic system with two molecules per unit cell. The Mn2+ cation is coordinated by four N-isoindole atoms of phthalocyaninato(2−) macrocycle and axially by two nitrogen atoms of pyridine molecules into a tetragonal bipyramid. The MnPc(py)2 crystals are moderately stable under air, but in pyridine solution the MnPc(py)2 complex undergoes oxidation by O2 yieldings the binuclear manganese(III) μ-oxo complex (MnPcpy)2O as evidenced by the UV–Vis spectroscopy. The magnetic susceptibility measurement performed on solid sample of MnPc(py)2 shows the Curie–Weiss behaviour in the temperature region of 300–15 K. The calculated magnetic moment μeff indicates three unpaired electrons (S=3/2), thus the ground state configuration of Mn ion is (a1g)2(eg)2(b2g)1, and the MnPc(py)2 complex is the intermediate spin complex. Below 5.5 K (TN) the magnetic susceptibility sharply decreases due to the cooperative intermolecular antiferromagnetic interactions.

Crystal and molecular structures of metal-free phthalocyanines, 1,2-dicyanobenzene tetramers. II: α form

Abstract Phthalocyanine (C32H16N8) is formed besides tin phthalocyanine in the reaction of AuSn4 with 1,2-dicyanobenzene at 210 °C and crystallizes in the monoclinic system (space group, P21/c). The unit-cell parameters are a = 14.803(3) A , b = 4.729(2) A , c = 19.870(4) A , β = 122.02(2)° and Z = 2. The refined structure with anisotropic temperature factors for carbon and nitrogen atoms and isotropic for hydrogen atoms gave R = 0.0487. The crystal structure data for metal-free phthalocyanines are discussed and compared with metal phthalocyanines. The phthalocyanine molecule is planar; the average derivation of the atoms from the phthalocyanine plane is 0.0257.

Synthesis, antiproliferative and antibacterial activity of new amides of salinomycin.

A series of 11 novel amides of salinomycin were synthesized for the first time. All the obtained compounds were found to show potent antiproliferative activity against human cancer cell lines including the drug-resistant cancer cells. Four new salinomycin derivatives revealed good antibacterial activity against clinical isolates of methicillin-resistant Staphylococcus epidermidis (MRSE).

Bis(melaminium) sulfate dihydrate

The crystals of a new melaminium salt, bis(2,4,6-triamino-1,3,5-triazin-1-ium) sulfate dihydrate, 2C3H7N6+*SO4(2-)*2H2O, are built up from monoprotonated melaminium(1+) residues, sulfate(2-) anions and water molecules. The SO4(2-) ion has a slightly distorted tetrahedral geometry. The melaminium residues are interconnected by N-H.N hydrogen bonds, forming chains. The chains of melaminium residues develop a three-dimensional network through multiple donor-acceptor hydrogen-bond interactions with sulfate anions and water molecules.

SYNTHESIS AND X-RAY CHARACTERIZATION OF THE IODINE-DOPED METALLODIPHTHALOCYANINE UPC2I5/3

Abstract Partially oxidized by iodine, uranium(IV) diphthalocyanine, U(C32H16N8)2I5/3, (UPc2I5/3), was obtained by the direct reaction of pure powder uranium with 1,2-dicyanobenzene under a stream of iodine. The compound crystallizes in a space group D4h2−P4/mcc of the tetragonal system with one molecule in a unit. The two heavy atoms (U and I) are disordered in the crystal. The crystal is composed of partially oxidized UPc2 units, which form a pseudo monodimensional stack along the [001] direction. The stacks are surrounded by disordered chains of iodine, identified as I3− ions by Raman spectroscopy. The EPR measurements (g=2.0014) confirm that phthalocyaninato ligand is partially oxidized.