ABSTRACT
Treatment of a recently reported complex [Ph4P][closo,nido-CoH(2,4-C2B8H10)(7,8-C2B8H11)] (1) either by H2O2 in acetone or NaH in THF leads to the loss of both the bridging and terminal hydrides yielding the diamagnetic salt of an anionic commo-cobaltacarborane [Ph4P][Co(2,4-isonido-C2B8H10)2] (2) with the {CoC2B8}-cluster units adopting a distorted skeletal geometry of the isonido-type. The anionic commo complex 2 reacts with in situ generated cationic [CuPPh3]+ species to give stable copper-cobalt zwitterion [Ph3PCu][Co(2,4-isonido-C2B8H10)2] (3) with four two-electron, three-center (B-H)4···Cu bonds, and exhibits no fluxional behavior in solution. Complex 3, at the same time, in CH2Cl2 in the presence of 2-fold excess of PPh3 readily converts to a new anionic species [(Ph3P)3Cu][Co(2,4-isonido-C2B8H10)2] (4) which retains initial isonido geometry. All newly obtained diamagnetic commo complexes were characterized by a combination of analytical and multinuclear NMR spectroscopic data and by single-crystal X-ray diffraction studies of complexes 2 and 3.
ABSTRACT
Fluorescent chromophore, alkylamino-(tetra-hydronaphthalenylidene)- benzothiazolium derivatives (HBTN dyes), are proposed as covalent labels for proteins via aliphatic amino groups. Spectral-luminescent properties of 3-methyl-2-{(E)-[7-(methylamino)-4,4a,5,6-tetra-hydronaphthalen-2(3H)-ylidene]methyl}-1,3-benzothiazol-3-ium chloride (HBTN, R=Me) and its predecessor, 2-[(E)-(7-methoxy-4,4a,5,6-tetrahydronaphthalen-2(3H)-ylidene)methyl]-3-methyl-1,3-benzothiazol-3-ium chloride (ABTN), are studied for free dyes and in the presence of DNA and BSA. Considerable spectral-luminescent changes accompany the transformation of ABTN into HBTN that allows monitoring conjugation reaction. In presence of DNA and BSA the HBTN increases its emission in 15 and 4 times respectively and becomes strongly fluorescent. The conditions for labeling are developed and a model conjugate of HBTN dye with BSA is synthesized. It was shown that using of HBTN dye as a fluorescent label allows detection by eye of about 3 mug/band of BSA on polyacrylamide gel upon UV-irradiation.
Subject(s)
DNA/metabolism , Fluorescent Dyes/chemistry , Proteins/metabolism , Serum Albumin, Bovine/metabolism , Spectrometry, Fluorescence/methods , Animals , Cattle , Chromatography, Liquid , DNA/chemistry , DNA/genetics , Electrophoresis, Polyacrylamide Gel , Fluorescent Dyes/chemical synthesis , Mass Spectrometry , Proteins/chemistry , Serum Albumin, Bovine/chemistry , Serum Albumin, Bovine/radiation effects , Ultraviolet RaysABSTRACT
The monocarbon carborane [Cs][nido-7-CB(10)H(13)] reacts with the 16-electron [RuCl(2)(PPh(3))(3)] in a solution of benzene/methanol in the presence of N,N,N',N'-tetramethylnaphthalene-1,8-diamine as the base to give a series of 12-vertex monocarbon arene-biruthenacarborane complexes of two types: [closo-2-[7,11-exo-RuClPPh(3)(mu,eta(6)-C(6)H(5)PPh(2))]-7,11-(mu-H)(2)-2,1-RuCB(10)H(8)R] (5, R = H; 6, R = 6-MeO; 7, R = 3-MeO) and [closo-2-(eta(6)-C(6)H(6))-10,11,12-[exo-RuCl(PPh(3))(2)]-10,11,12-(mu-H)(3)-2,1-RuCB(10)H(7)R(1)] (8a, R(1) = 6-MeO; 8b, R(1) = 3-MeO, inseparable mixture of isomers) along with trace amounts of 10-vertex mononuclear hypercloso/isocloso-type complexes [2,2-(PPh(3))(2)-2-H-3,9-(MeO)(2)-2,1-RuCB(8)H(7)] (9) and [2,5-(Ph(3)P)-2-Cl-2-H-3,9-(MeO)(2)-2,1-RuCB(8)H(6)] (10). Binuclear ruthenacarborane clusters of both series were characterized by a combination of analytical and multinuclear NMR spectroscopic data and by single-crystal X-ray diffraction studies of three selected complexes, 6-8. In solution, isomers 8a,b have been shown to undergo the isomerization process through the scrambling of the exo-[RuCl(PPh(3))(2)] fragment about two adjacent triangular cage boron faces B(7)B(11)B(12) and B(8)B(9)B(12).
