Photooxygenation of alkynylperylenes. Formation of dibenzo[jk,mn]phenanthrene-4,5-diones

3-(1-Alkynyl)perylenes undergo oxygenation when subjected to irradiation with visible light under aerated conditions. The structures of novel oxygenated products formed in this manner are assigned as regioisomeric dibenzo[jk,mn]phenanthrene-4,5-diones.     

Synthesis of bioreductive esters from fungal compounds

Four new bioreductive esters (7-10) have been synthesized. Their structures composed of trimethyl lock containing quinone propionic acid with an ester linkage to the fungal cytotoxic compounds; preussomerin G (1), preussomerin I (2), phaseolinone (3) and phomenone (4). The synthesized esters are aimed to act via reductive activation specifically at the cancer cells, resulting from hypoxia and overexpression of reductases. Hence, the toxicity will be lessened during distribution across the normal cells. The anticancer activity was determined in cancer cell lines with reported reductase i.e., BC-1 cells and NCI-H187 as well as in non-reductase containing cancer cells; KB cells. When considering each cell lines, result showed that structure modification giving to 7-10 led to less cytotoxicity than their parent compounds (1-4). Both 7 and 8 were strongly cytotoxic (IC50 < or = 5 microg/ml) to NCI-H187, whereas 9 and 10 were moderately cytotoxic (IC50 = 6-10 microg/ml) to BC-1 cells. Additional study of stability of represented phenolic ester (8) and an alcoholic ester (9) were performed. Result illustrated that both 8 and 9 were stable in the presence of esterase. Therefore, the cytotoxicity of the synthesized compounds (8-10) might be due to partial bioreductive activation in the cancer cells.     

New constituents from the leaves of Morinda citrifolia

A new iridoid glycoside, citrifoside (1), and a new anthraquinone, 1,5,15-trimethylmorindol (2), together with 24 known compounds, were isolated from the leaves of Morinda citrifolia. The structures of the new compounds were elucidated by spectral data. 1,5,15-Trimethylmorindol (2) did not show significant cytotoxic activity by itself but showed cytotoxicity when combined with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), while citrifoside (1) did not show any activity even with TRAIL.     

Microelectrospray interface with coaxial sheath flow for high-resolution capillary electrophoresis/mass spectrometry separation

We have fabricated a coaxial sheath liquid flow microelectrospray ionization (microESI) interface for capillary electrophoresis coupled with mass spectrometry (CE/MS). The ESI interface, which features a reduced probe diameter (130 microm i.d. x 174 microm o.d.) with a nebulizer-free format, can relatively easily electrospray a large amount of make-up sheath liquid (5-10 microL/min) over the long term (more than 80 runs) with a high degree of stability. The interface also provides higher separation qualities and improved detection sensitivities compared with a conventional ion spray (IS) interface.     

Increased crystal porosity and enhanced gas adsorption by intracolumnar gliding for broadband gas detection

A new three-level structural approach based on anion-induced intracolumnar gliding of stacked coordinatively unsaturated units is described for design of metal-organic crystals which exhibit concentration- and gas-specific adsorption of a variety of small molecules and could be employed for multiple and rapid qualitative and quantitative broadband detection of gases or gaseous mixtures.     

Analysis of the thermal properties of a liquid 1-butanol polymer composed during a plasma-induced reaction

This paper investigates the mechanisms of thermosetting and simultaneous hydrogen desorption of liquid 1-butanol polymer composed during a plasma-induced reaction. A transparent liquid 1-butanol polymer consisting of partially dissociated 1-butanol, oxygen, and nitrogen gradually gains viscosity at less than 50 degrees C and transforms to a solid between 100 and 150 degrees C. This polymer also traps at least 0.225 mass % hydrogen during its composition and thermally desorbs the hydrogen between 26 and 150 degrees C. Electron probe microanalyses (EPMA) and FTIR analyses indicate that 11 wt % nitrogen fixed from the air is the principal component in the formation of stable 3-D bridge structures and the resultant thermosetting of the polymer. Thermal-desorption analysis and electrical resistivity measurements also support the theory that some hydrogen is electrically trapped as quasi-stable ions around negatively polarized OH and/or C=O bonds in the polymer, contributing to both electrical conductivity and the desorption of hydrogen.     

One-pot regioselective synthesis of chromanyl(phenyl)-lambda(3)-iodanes: tandem oxidative cyclization and lambda(3)-iodanation of 3-phenylpropanols

Reaction of 3-phenylpropanol with an activated iodosylbenzene-18-crown-6 complex [PhI(OH)BF4-18C6] in dichloromethane in the presence of BF3-Et2O afforded directly the 6-chromanyl(phenyl)-lambda3-iodane-18C6 complex through tandem oxidative intramolecular cyclization yielding chroman and its regioselective phenyl-lambda3-iodanation.