Weak Interactions in the Structures of Newly Synthesized (–)-Cytisine Amino Acid Derivatives

Eight new (–)-(N-[(AA)-(N-phtaloyl)]cytisines (where AA is amino acid: glycine, β-alanine, D,L-valine, L-valine, L-isoleucine, L-leucine, D-leucine and D,L-phenyloalanine), were synthesized and fully spectroscopically characterized (NMR, FTIR and MS). For two of these compounds, N-[glycine-(N-phtaloyl)]cytisine and N-[L-isoleucine-(N-phtaloyl)]cytisine, X-ray crystal structures were obtained and used as the basis for an in-depth analysis of intermolecular interactions and packing energies. The structural geometrical data (weak hydrogen bonds, π···π interactions, etc.) were compared with the energies of interactions and the topological characteristics (electron density, Laplacian at the appropriate critical point) based on the atoms-in-molecules theory. The results suggest that there is no straightforward connection between the geometry of point-to-point interactions and the molecule-to-molecule energies. Additionally, the usefulness of the transfer of multipolar parameters in estimating of critical points’ characteristics have been confirmed

Synthesis, characterization, and biological properties of mono-, di- and poly-nuclear bismuth(III) halide complexes containing thiophene-2-carbaldehyde thiosemicarbazones

In order to investigate the coordination chemistry and pharmacological applications of bismuth compounds, a series of new bismuth(III) halide thiosemicarbazone complexes were synthesized. The reactions of thiophene-2-carbaldehyde-N-substituted thiosemicarbazones with bismuth(III) halides resulted in the formation of the {[[BiCl2(eta 1-S-Httsc)4]+.Cl-][BiCl2(mu 2-Cl)(eta 1-S-Httsc)2]2} (1), {[BiCl3(eta 1-S-Htmtsc)3].CH3OH} (2), {[BiCl3(eta 1-S-Htetsc)3].CH3OH} (3), {[BiBr2(mu 2-Br)(eta 1-S-Httsc)2]2.CH3OH} (4), {[BiBr2(mu 2-Br)(eta 1-S-Htmtsc)2]n} (5), and {[BiI2(mu 2-I)(eta 1-S-Httsc)2]2} (6) complexes (Httsc: thiophene-2-carbaldehyde thiosemicarbazone, Htmtsc: thio-phene-2-carbaldehyde-N-methyl thiosemicarbazone, Htetsc: thiophene-2-carbaldehyde-N-ethyl thio-semicarbazone). The complexes were characterized by a number of different spectroscopic techniques and the crystal structures of all bismuth(III) complexes (1-6) were determined by using single crystal X-ray diffraction study. In addition, the thermal stability of the complexes was compared using Thermogravimetric-differential thermal analysis. Crystal structures of the two free ligands, thiophene-2-carbaldehyde-N-methyl-thio-semicarbazone and thiophene-2-carbaldehyde-N-ethyl-thiosemicarbazone, were also determined by using single crystal X-ray diffraction analysis. The Hirshfeld surface of the bismuth(III) complexes and free ligands were additionally analyzed to verify the intermolecular interactions. Biological studies showed that all six bismuth(III) thiosemicarbazone complexes (1-6) exhibited biological activities against selected bacteria and the human breast adenocarcinoma (MCF-7) cell line.Scientific and Technological Research Council of Turkey (TUBITAK); [121Z222]Acknowledgements This research was carried out in partial fulfillment of the re-quirements for the master thesis of K.T. under the supervision of I.I.O. This work was supported by The Scientific and Technological Research Council of Turkey (TUBITAK, Project No. 121Z222)

Cd(II) and Cu(II) coordination polymers constructed from the expanded 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene ligand: conventional and ultrasound-assisted synthesis, crystal structure, luminescence and magnetic properties

A 3D open inorganic/organic framework, {[Cd(mu-L)(mu(3)-SO4)(H2O)]center dot H2O}(n) (1) [L = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene] was synthesized by the reaction of CdSO4 center dot 8H(2)O with L. The treatment of Cu(NO3)(2)center dot 3H(2)O with the same N,N'-donor ligand in two different solvent mixtures, methanol/ dichloromethane (2) and methanol/ chloroform (3), afforded two new ladder-like coordination polymers of formula {[Cu(mu-L)(mu-NO3)(NO3)]center dot solv}(n) [solv = CH2Cl2 (2) and CHCl3 (3)]. The non-interpenetrated ladder motifs 2 and 3 enclathrate the uncoordinated solvent molecules. Crystalline coordination polymers 1 and 3 were also successfully prepared by a sonochemical method under different reaction conditions. Our results indicate that the size of the particles is dependent on the irradiation time. 1 and 3 exhibit intense luminescent emissions in the solid state at room temperature. Cryomagnetic measurements of 3 show the occurrence of a ferromagnetic interaction between the copper(II) ions through the double oxo-nitrate bridge together with a very weak inter-ladder antiferromagnetic interaction [J = +4.93(2) cm(-1), g = 2.10(1) and Theta = -0.567(5) K]