Facile Synthesis of 3-Substituted Thiazolo[2,3-α]tetrahydroisoquinolines.

It was found that 4-hydroxy-2-butenoic ester could not react with 3,4-dihydro-isoquinoline (). Individual addition reactions of γ-mercapto-α,β-unsaturated esters ( and -unsaturated amide ( with 3,4-dihydroisoquinolines () were carried out under appropriate conditions to provide the corresponding thiazolo[2,3-α]isoquinoline derivatives with good yields (up to 87%) and significant diastereomeric selectivity. The mechanism of the crucial reaction was discussed.

Total Synthesis of (+)-Antrocin and Its Diastereomer and Clarification of the Absolute Stereochemistry of (-)-Antrocin.

Using 2,2-dimethyl cyclohexanone as the starting compound, (+)-antrocin and its diastereomer have been synthesized. The absolute stereochemistry of (-)-antrocin, a natural sesqui-terpenoid and an antagonist in some types of cancer cells, was clarified using the character data of (+)-antrocin. The synthetic procedure involved two key steps: (1) the reaction of vinyl magnesium bromide with 2,2-dimethyl-6-t-butyl-dimethyl-silyoxy-methyl-1-cyclo-hexanone to give a vinyl cyclohexanol derivative and (2) a highly stereoselective intramolecular Diels-Alder (IMDA) reaction of the camphanate-containing triene intermediate.

Inhibition of pentraxin 3 in glioma cells impairs proliferation and invasion in vitro and in vivo.

Pentraxin 3 (PTX3) is an inflammatory molecule that is involved in immune responses, inflammation, and cancer. Recent evidence suggests that PTX3 plays a critical role in tumor progression; however, its impact on the biological function of gliomas remains unknown. In the present study, immunohistochemical staining showed that patients with high-grade gliomas exhibited increased expression levels of PTX3 compared to those with low-grade gliomas (P < 0.

Pyromellitic dithioimides: thionation improves air-stability and electron mobility of N-type organic field-effect transistors.

Thionation and fluorination of pyromellitic diimides (PyDIs) increased the electron mobility and on/off ratio of the original diimides by two orders of magnitude and improved the threshold voltage and air-stability of diimide compounds.

Linear oligoarylamines: electrochemical, EPR, and computational studies of their oxidative states.

A series of straight-chain oligoarylamines were synthesized and examined by electrochemical, spectroelectrochemical, electron paramagnetic resonance techniques, and density functional theory (DFT) calculation. Depending on their electrochemical characteristics, these oligoarylamines were classified into two groups: one containing an odd number and the other an even number of redox centers. In the systems with odd redox centers (N1, N3, and N5), each oxidation was associated with the loss of one electron.

Electrochemically controlled multiple hydrogen bonding between triarylamines and imidazoles.

By increasing the number of amino substituents on triarylamine, the extent of hydrogen bonding between the oxidized form of triarylamine and imidazole could be electrochemically controlled. Three behaviors, depending on the interaction between oxidized amine and imidazole, were obtained in CV patterns. DFT calculation was used to confirm that the electron density of protons of the amino group decreased as the amino moiety increased.

Studies on the structure of N-phenyl-substituted hexaaza[1(6)]paracyclophane: synthesis, electrochemical properties, and theoretical calculation.

The N-phenyl-substituted hexaaza[1(6)]paracyclophane (3, hexamer) has been synthesized successfully in two steps and the noncoplanar conformation was calculated by gaussian program. The electrochemical properties exhibited lots of interesting results and each overlapping oxidative wave contained two-electron transfer.

Selective ring expansion alkylation of formyl[2.2.1]bicyclic carbinols with C-nucleophiles: a unique route to cyclopentane derivatives.

Reactions of camphor-, and camphene-derived formyl [2.2.1]bicyclic carbinols with Grignard and organolithium reagents afford the corresponding regio- and stereospecific alkyl/aryl [3.

Isolation and quantitative analysis of cryptotanshinone, an active quinoid diterpene formed in callus of Salvia miltiorrhiza BUNGE.

Effect of N(6)-benzyladenine (BA) on tanshinone formation in callus cultures of Salvia miltiorrhiza was examined in an attempt to increase the productivity of the medicinal compound, cryptotanshinone. Primary callus was induced by culturing leaf explants on Murashige and Skoog's (MS) basal medium supplemented with 1.0 mg l(-1) of 2,4-dichlorophenoxyacetic acid (2,4-D) in darkness.