Synthesis and characterization of phosphorescent cyclometalated iridium complexes.

The preparation, photophysics, and solid state structures of octahedral organometallic Ir complexes with several different cyclometalated ligands are reported. IrCl3.nH2O cleanly cyclometalates a number of different compounds (i.e., 2-phenylpyridine, 2-(p-tolyl)pyridine, benzoquinoline, 2-phenylbenzothiazole, 2-(1-naphthyl)benzothiazole, and 2-phenylquinoline), forming the corresponding chloride-bridged dimers, CwedgeN2Ir(mu-Cl)2IrCwedgeN2 (CwedgeNis a cyclometalated ligand) in good yield. These chloride-bridged dimers react with acetyl acetone (acacH) and other bidentate, monoanionic ligands such as picolinic acid (picH) and N-methylsalicylimine (salH), to give monomeric CwedgeN2Ir(LX) complexes (LX = acac, pic, sal). The emission spectra of these complexes are largely governed by the nature of the cyclometalating ligand, leading to lambda(max) values from 510 to 606 nm for the complexes reported here. The strong spin-orbit coupling of iridium mixes the formally forbidden 3MLCT and 3pi-pi* transitions with the allowed 1MLCT, leading to a strong phosphorescence with good quantum efficiencies (0.1-0.4) and room temperature lifetimes in the microsecond regime. The emission spectra of the CwedgeN2Ir(LX) complexes are surprisingly similar to the fac-IrCwedgeN3 complex of the same ligand, even though the structures of the two complexes are markedly different. The crystal structures of two of the CwedgeN2Ir(acac) complexes (i.e., CwedgeN = ppy and tpy) have been determined. Both complexes show cis-C,C', trans-N,N' disposition of the two cyclometalated ligands, similar to the structures reported for other complexes with a "CwedgeN2Ir" fragment. NMR data (1H and 13C) support a similar structure for all of the CwedgeN2Ir(LX) complexes. Close intermolecular contacts in both (ppy)2Ir(acac) and (tpy)2Ir(acac) lead to significantly red shifted emission spectra for crystalline samples of the ppy and tpy complexes relative to their solution spectra.

[The behavior of inulin in aqueous solutions under exposure to gamma radiation]. / Issledovanie povedeniia inulina v vodnykh rastvorakh pod vozdeistviem gamma-izlucheniia.

Radiochemical transformations of inulin in aqueous solutions, in air, in the presence of inert gases, helium, nitrogen, and in nitrous oxide exposed to various doses of 60Co gamma irradiation were investigated. It was shown that interactions of inulin with OH radicals are principally responsible for radiolytic decomposition of inulin. The data on radiolysis of more simple model systems were used to make available decomposition of absorption spectra of gamma-irradiated aerated aqueous solution of inulin.

[The clinico-morphological characteristics of glomerulonephritis in infectious endocarditis]. / Kliniko-morfologicheskaia kharakteristika glomerulonefrita pri infektsionnom éndokardite.

Clinicomorphological characteristics of glomerulonephritis in infectious endocarditis (IEGN) were studied in 62 patients (with samples of autopsy material being used in 52 instances). IEGN presents with dissaminated and focal proliferative alterations involving extracapillary and/or tubulointerstitial components, and is characterized by a broad variability of indices for proteinuria, hematuria and cylindruria. In diffuse prolipherative glomerulonephritis the degree of proteinuria and cylindruria appear to be significantly higher than in focal segmental proliferative glomerulonephritis, as is the incidence rate of development of renal insufficiency and its gravity.

[The prognosis of the nature of the course and outcome of infectious endocarditis]. / Prognozirovanie kharaktera techeniia i iskhoda infektsionnogo éndokardita.

Prognostic significance of various clinical and laboratory indices for predicting the course and outcome of infectious endocarditis (IE) has been analyzed for 139 IE patients aged 15-68 (77 males and 62 females). The unfavourable prognosis was associated with uncontrollable sepsis, persistence of circulating immune complexes and developing glomerulonephritis. The latter had also prognostic signs unfavourable for IE: moderate or severe proteinuria and/or cylindruria, reduced renal function, diffuse proliferation, pronounced extracapillary and/or tubulointerstitial components.

[Significance of the studies of urinary syndrome in clinical practice]. / Znachenie izucheniia mochevogo sindroma v klinicheskoi praktike.

The study of urinary sediment is essential in laboratory diagnosis. Conventional clinical methods are now used in line with computer-aided techniques and additional microscopy of the sediment elements. The paper provides a brief analysis of clinical situations characterized by appearance in the urine of abnormal numbers of leukocytes, erythrocytes, casts; provides clinical assessment of additional microscopic methods able to accentuate qualitative characteristics of the urinary syndrome; considers possibilities of application of the urinary sediment data in follow-up to improve diagnosis and control on-going treatment.