Rhenium bipyridine complexes for the recognition of glucose

Three metal(II) complexes constructed using the 2-(1H-benzo[d]imidazol-2-yl)quinoline ligand

2-(1H-benzo[d]imidazol-2-yl)quinoline (BQ) as ligand and three coordination compounds of formula {Zn(BQ)Cl2} (1), {Pb(BQ)Cl2} n (2) and {[Cu(BQ)2(OC(O)CH3)]OC(O)CH3 · CH3COOH} (3) have been synthesized and fully characterized. The complexes crystallize in triclinic space group P 1 ‾ $P‾{1}$ . In complexes 1 and 2, the coordination geometry is a distorted tetrahedral environment around the zinc center and a distorted sixfold coordination geometry around the lead center, respectively. In complex 3 the central Cu(II) center is in a trigonal bipyramidal coordination geometry. The Cu(II) ion is surrounded by two bidentate 2-(2′-quinolyl)benzimidazole (BQ) ligands and one coordinated acetate molecule. One further acetate anion associated by a strong hydrogen bond with a molecule of acetic acid balances the charge of the compound.

Luminescent iridium(iii)–boronic acid complexes for carbohydrate sensing

A family of four Ir(iii) complexes with either pyridyl-1,2,4-triazole or pyridyl-1,3,4-oxadiazole ligands bearing boronic acid groups have been prepared as potential luminescent sensors for carbohydrates.

A new fluorescence and colorimetric sensor for highly selective and sensitive detection of glucose in 100% water

A new naphthalimide derivative containing hexanoic acid and boronate groups was designed and synthesized.

Anticancer conjugates and cocktails based on methotrexate and nucleoside synergism

Conjugates of methotrexate (MTX) and the nucleoside analogs 3-azidodeoxythymidine (AZT), iododeoxyuridine (IUdR) and dideoxycytidine (ddC) linked using poly(ethyleneglycol) are presented. In vitro cytotoxicity assays of the conjugates against drug resistant ovarian cell line A2780/AD are preformed and comparisons made to such assays performed for unconjugated (cocktail) systems. All systems tested were inactive, or had low activity, at 24 h. After 72 hr incubation however, the cocktails of MTX and AZT, IUdR or ddC showed high cytotoxicity in the low nanomolar range. The conjugates were only very moderately active with IC(50) values in the [0.1 to 1.0 mM] range. Conjugation of the antifolate to the nucleoside analogs has it seems reduced the activity significantly when compared to a cocktail of the components, indicating a conjugate approach is unlikely to translate into success in vivo. The positive note comes from the observation that by combining two of the new conjugates, namely those based on MTX with IUdR or AZT, an IC50 at 24 hours of ~ [180 muM] was produced.

Ultrafast Photoinduced Electron Transfer within a Self-Assembled Donor−Acceptor System

A photoactive supramolecular assembly that is based on the hydrogen-bonded system H1.G2, consisting of a methyl viologen-functionalized barbiturate host (H1) (1-(N-(3,5-bis[[(6-tert-butylacetylamino-2-pyridyl)amino]carbonyl])-phenylacetamide)-1'-methyl-4,4'-bipyridium) and a [Re(Br)(CO)3(barbi-bpy)] (barbi-bpy = 5-[4-(4'-methyl)-2,2'-bipyridyl]methyl-2,4,6-(1H,3H,5H)-pyrimidinetrione) complex as the guest (G2) is described. The host molecule contains a well-known electron accepting group (methyl viologen), whereas the guest system can act as an efficient electron donor in the excited state. Upon self-assembly, the resulting adduct (H1.G2) represents an interesting noncovalently linked donor-acceptor system. The H1.G2 complex has been characterized in acetonitrile-d3 using 1H NMR and diffusion-ordered NMR spectroscopy (DOSY). The photophysical properties of the components and of the assembly have been studied in dichloromethane, in which the assembly has a high binding constant (Kass > or = 2 x 10(5) M(-1)), using time-resolved fluorescence and transient absorption spectroscopy. A detailed investigation of the hydrogen-bonded complex H1.G2 revealed that, upon excitation of the rhenium compound G2, an ultrafast electron-transfer process occurs from the metal-based component to the acceptor unit. The kinetics of the forward and back electron-transfer processes have been determined.