Sixteen arene-Ru based molecular-rectangles were self-assembled in high yields by the equimolar mixing of arene-Ru acceptors (Aa-Ad) with various azopyridyl ligands (1,2-di(pyridyl-4yl)diazene (L1), 1,2-bis(pyridin-4-ylmethylene)hydrazine (L2), 1,2-bis(1-(pyridin-4-yl)ethylidene)hydrazine (L3), 1,2-bis(pyridin-4-ylmethylene)hydrazine (L4)) in nitromethane-methanol solutions. These new molecular-rectangles were fully characterized by a host of analytical techniques including elemental analysis, (1)H and (13)C NMR and HR-ESI-MS. The solid-state structures of two molecular-rectangles (1b and 4d) were determined by single crystal X-ray diffraction data. UV-visible and fluorescence studies were also carried out for the entire suite of rectangles. As with recent studies of similar arene-Ru complexes, the anti-proliferative activities of these complexes were evaluated against SK-hep-1 (liver cancer) and A-549 (lung cancer) human cancer lines. Additionally, the cellular pharmacology and intracellular localizations in AGS (gastric cancer) human cancer cells were determined for selected complexes (1c, 1d and 4c) by apoptosis and fluorescence microscopy studies. These studies confirm that arene-Ru molecular-rectangles inhibit cell cycle progression to the G0 phase, in contrast to that of cisplatin which arrests cell growth in the G2 phase.

The plasmonic coupling between the interacting noble metal nanoparticles plays an important role to influence the optical properties of arrays. In this work, we have extended the Mie theory results of our recent communication to include the effect of particle interactions between the alloy nanoparticles by varying interparticle distance and number of particles. The localized surface plasmon resonance (LSPR) peak position, full width at half maxima (FWHM) and scattering efficiency of one dimensional (1D) bimetallic alloy nanosphere (BANS) arrays of earlier optimized compositions i.e. Ag0.75Au0.25, Au0.25Cu0.75 and Ag0.50Cu0.50 have been studied presently by using discrete dipole approximation (DDA) simulations. Studies have been made to optimize size of the nanosphere, number of spheres in the arrays, material and the interparticle distance. It has been found that both the scattering efficiency and FWHM (bandwidth) can be controlled in the large region of the electromagnetic (EM) spectrum by varying the number of interacting particles and interparticle distance. In comparison to other alloy arrays, Ag0.50Cu0.50 BANS arrays (each of particle radius 50 nm) shows larger tunability of LSPR with wide bandwidth (essential condition for plasmonic solar cells).

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Some new mixed ligand dibutyltin(IV) complexes of the type Bu 2 SnLA [where LH = RC(0)CH 2 C(0)R', R = -QHj and R' = -CH 3 (L,H), R = -C 6 H 5 and R' = -CF^LjH), R = -C 4 H 3 S and R' = -CF 3 (L 3 H) andAH=t(0)QH4C(0)NfCHR"C00H, R"= -H(A,H), R"= -CH 3 (A 2 H),R"= -CHaQHs (A 3 H), -CHR" = -CH 2 CH 2 -(A4H)] have been prepared by the reaction of dibutyltin(IV) dichloride with the corresponding ligands in the presence of triethylamine in 1:1:1:2 molar ratios in dry refluxing THF solution. The structural elucidation of these newly synthesised complexes is based upon physico-chemical and spectroscopic studies. These complexes possess penta-coordinated tin centres as inferred from U9 Sn NMR spectral studies of some of these complexes.Brought to you by | Purdue University Libraries Authenticated Download Date | 6/1/15 12:30 AM fluorinated ß-diketones on the properties of the resulting mixed ligand organotin(IV) complexes. In this paper, we report the preparation, structural aspects and spectral studies of some mixed ligand complexes of dibutyltin(IV) of ß-diketones, fluorinated ß-diketones and N-protected amino acids. EXPERIMENTALAll the reactions were carried out under strictly anhydrous conditions. Dibutyltin(IV) dichloride (Lancaster) was distilled (135°/10mm) before use. All the solvents were dried by standard methods. Tin was estimated as tin(IV) oxide. Melting points were determined in sealed capillaries. Molecular weight measurements were carried out by determining depression in freezing point and were found to be in agreement with calculated values (Table 1). N-protected amino acids were synthesised by the method reported by Sheehan /20/. ß-Diketones were commercially available.

The interaction of titanocenedichloride with various monofunctional bidentate ligands in different stoichiometric ratios affords products of variable compositions depending upon the nature of the ligands and experimental conditions. [1][2][3] An exhaustive survey of the literature reveals that a large number of dicyclopentadienyl titanium(IV) complexes of the types [Ti(C 5 H 5 ) 2 ClL], [TiC 5 H 5 ClL 2 ] and [Ti(C 5 H 5 ) 2 L 2 ] (where L = monofunctional bidentate ligand) have been synthesised and extensively studied 4-6 due to their interesting chemistry and applications. Metallocene catalysts 7-9 are put to use for the industrial polymerisation of alkenes. [10][11][12][13] It is reported that some of the derivatives of titanocenedichloride exhibit an antitumour effect, 14,15 this has provided an impetus for further studies in this field.N-protected amino acids and heterocyclic β-diketones are the potential organic ligands which have aroused much interest because of their interesting bonding patterns 16,17 and potential biological applications of their metal complexes. [18][19][20] Much interest has been focused on the chemistry of complexes of these ligands with group IV and XIV metals. 16,17,[21][22][23][24][25][26] However, there is no literature report on the synthesis of mixed ligand complexes of titanocenedichloride derived from these ligands. As an extension of the work described in our previous communications, 22,27 it was considered relevant to prepare mixed ligand complexes of dicyclopentadienyl titanium(IV) of these potential organic ligands. The present work has the objective of seeking more information concerning the nature of bonding and comparative ligating capability of these ligands towards dicyclopentadienyl titanium(IV). Results and discussionDicyclopentadienyl titanium(IV) complexes of general formula [TiCp 2 LA] where LH= RCOC:C(OH)N(C 6 H 5 )N:CCH 3 and AH = HOOC-CHR'NC(O)C 6 H 4 C(O) [R = -C 6 H 5 , -CH 3 , -C 2 H 5 and R' = -H, -CH 2 C 6 H 5 , -CH 3 and -CH(CH 3 ) 2 ]have been synthesised by the interaction of titanocenedichloride with congested heterocyclic β-diketones (LH) and N-protected amino acids (AH) in the presence of triethylamine in a 1:1:1:2 molar ratio in refluxing THF solution, see below.After filtering off triethylamine hydrochloride formed during the reaction and stripping the volatile fraction under reduced pressure, coloured solid powders were obtained which were recrystallised from CHCl 3 /n-hexane mixture in 48 to 56% yield. These solid derivatives have sharp melting points and are highly soluble in common organic solvents like THF, benzene and chloroform. The newly synthesized mixed ligand complexes of dicyclopentadienyl Ti(IV) derived from N-protected amino acids and heterocyclic β-diketones were subjected to spectral (IR, 1 H NMR and 13 C NMR) studies and information inferred from these studies has been used to diagnose the nature of bonding and to elucidate the plausible structures of these complexes. IR spectral studiesThe IR spectra of these complexes are record...

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