Spiro[fluorene-9,9?-xanthene]-based HTMs for high efficiency red and green PHOLEDs with low roll-off.

The title compound, C(33)H(34)N(4)O(2)S·CH(3)OH, was prepared as a spiro-lactam ring formation of rhodamine 6 G dye for comparison with a ring-opened form. The xanthene and spiro-lactam rings are approximately planar [r.m.s. deviations from planarity = 0.122 (3) and 0.072 (6) Å, respectively]. The dihedral angles formed by the spiro-lactam and thio-phene rings with the xanthene ring system are ...

The title compound, C(28)H(30)N(2)OS(2), was obtained by thio-nation of 3',6'-bis-(diethyl-amino)-3H-spiro-[isobenzofuran-1,9'-xan-thene]-3-one with 2,4-bis-(p-methoxy-phen-yl)-1,3-dithia-diphos-phetane disulfide (Lawesson's reagent). The planes of the two benzene rings of the xanthene system are inclined at a dihedral angle of 17.4 (1)°, and the plane of the dithio-phthalide group and the plan...

We have investigated the kinetics of novel carbon-to-metal hydrogen atom transfer reactions, in which homolytic cleavage of a C-H bond is accomplished by a single metal-centered radical. Time-resolved IR spectroscopic measurements revealed efficient hydrogen atom transfer from xanthene, 9,10-dihydroanthracene, and 1,4-cyclohexadiene to Cp(CO)2Os(•) and (η(5)-(i)Pr4C5H)(CO)2Os(•) radicals, forme...

5' AMP-activated protein kinase (AMPK) is a highly conserved serine-threonine kinase that regulates energy expenditure by activating catabolic metabolism and suppressing anabolic pathways to increase cellular energy levels. Therefore AMPK activators are considered to be drug targets for treatment of metabolic diseases such as diabetes mellitus. To identify novel AMPK activators, we screened xan...

The title compound, C(28)H(30)N(2)O(3)·C(9)H(10)O(5), is a well known red leuco complex of 2-(6-diethyl-amino-3-diethyl-iminio-3H-xanthene-9-yl)benzoate (rhodamine B base abbreviated to RBB: leuco dye) with ethyl gallate (EG: developer). The structure of the complex at room temperature has recently been reported by Sekiguchi, Takayama, Gotanda & Sano [(2007) Chem. Lett. 36, 1010-1011]. The RBB-...

An up to 18-fold increase of the turnover frequency (TOF) in the catalase-like hydrogen peroxide dismutation reaction is observed by incorporation of substituents in the β-position of xanthene-modified iron corroles.

Key words oxonium ions - stereogenic oxygen oxepin xanthene pyramidal inversion quantum calculation

Following the results we previously reported on a series of xanthene and xanthone derivatives as G-quadruplex stabilizing ligands, in order to obtain a more selective compound with respect to the previous generation of derivatives, we decided to modify the structure of the core ligand, specifically its aromatic extension. In particular, here we report the design, synthesis and activity data of ...

The title compound, C(28)H(30)N(2)O(3)·C(9)H(10)O(5), is a well known red leuco complex of 2-(6-diethylamino-3-diethyl-iminio-3H-xanthen-9-yl)benzoate (rhodamine B base abbreviated to RBB, a leuco dye) with ethyl gallate (EG, developer). The structure of the complex at room temperature has recently been reported by Sekiguchi, Takayama, Gotanda & Sano [Chem. Lett. (2007 ▶), 36, 1010-1011]. We ha...