Center for Magnetic Resonance

A.A. Beljaev, D.V. Krupenya, E.V. Grachova, V.V. Gurzhiy, A.S. Melnikov, P.Yu. Serdobintsev, E.S. Sinitsyna, E.G. Vlakh, T.B. Tennikova, S.P. Tunik

“Supramolecular AuI-CuI complexes as new luminescent labels for covalent bioconjugation”

Bioconjugate Chem., 2015
DOI:10.1021/acs.bioconjchem.5b00563

Two new supramolecular organometallic complexes, namely, [Au₆Cu₂(C₂C₆H₄CHO)₆(PPh₂C₆H₄PPh₂)₃](PF₆)₂ and [Au₆Cu₂(C₂C₆H₄NCS)₆(PPh₂C₆H₄PPh₂)₃](PF₆)₂, with highly reactive aldehyde and isothiocyanate groups have been synthesized and characterized using X-ray crystallography, ESI mass spectrometry, and NMR spectroscopy. The compounds obtained demonstrated bright emission in solution with the excited-state lifetime in microsecond domain both under single- and two-photon excitation. The luminescent complexes were found to be suitable for bioconjugation in aqueous media. In particular, they are able to form the covalent conjugates with proteins of different molecular size (soybean trypsin inhibitor, human serum albumin, rabbit anti-HSA antibodies). The conjugates demonstrated a high level of the phosphorescent emission from the covalently bound label, excellent solubility, and high stability in physiological media. The highest quantum yield, storage stability, and luminance were detected for bioconjugates formed by covalent attachment of the aldehyde-bearing supramolecular AuI–CuI complex. The measured biological activity of one of the labeled model proteins clearly showed that introduced label did not prevent the biorecognition and specific protein–protein complex formation that was extremely important for the application of the conjugates in biomolecular detection and imaging.

D.S. Ryabukhin, A.V. Vasilyev

“A synthesis of 4-aryl quinolin-2(1H)-ones by acidic zeolite promoted intramolecular cyclization of N-aryl amides of 3-arylpropynoic acids”

Tetrahedron Lett., 2015, 56, 2200-2202
DOI:10.1016/j.tetlet.2015.03.060

N-Aryl amides of 3-arylpropynoic acids are intramolecularly cyclized into 4-aryl quinolin-2(1H)-ones in high yields without any by-products under the action of acidic zeolite CBV-720 in benzene at 130 °C in a glass high pressure tube.

A.V. Galenko, A.F. Khlebnikov, M.S. Novikov, M.S. Avdontseva

“Synthesis of 3-(1,2-dioxoethyl)- and 2,3-dicarbonyl-containing pyrroles”

Tetrahedron, 2015, 71, 1940-1951
DOI:10.1016/j.tet.2015.02.030

The transition metal-catalyzed reaction of 2H-azirines with 1,2,4-tricarbonyl compounds leads to 3-(1,2-dioxoethyl)- and 2,3-dicarbonyl-pyrrole derivatives, useful building blocks for the preparation of 3-heterocyclyl pyrroles and pyrroles fused with heterocycles. The influence of catalysts and the reaction conditions on the yields of pyrroles and the regioselectivity of the reaction were studied. Experimental and theoretical results suggest that the reaction proceeds via the formation of an intermediate azirine–metal complex and subsequent nucleophilic N–C³ bond cleavage.