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tert-Butyl-1,3-dimethylpyrene 5-carbaldehyde and 7-tert-butyl-1,3-dimethylpyrene 5,9-dicarbalde- hyde were converted to the corresponding (4-methoxyphenylethynyl)pyrenes by the Wittig reaction with 4-methoxyphenyl methyl phosphonium ylide followed by bromination and dehydrobromination. Single-crystal X-ray analysis of 7-tert-butyl-5-(4-methoxyphenylethynyl)-1,3-dimethylpyrene revealed that there is a 1-D, slipped, face-to-face motif with off-set, head-to-tail stacked columns, which are clearly influenced by the single, bulky, tert-butyl group in the pyrene ring at the 7-position. Detailed studies on photophysical properties and electrochemical characteristics in solutions strongly indicate that they might be promising candidates for organic optoelectronic applications, such as organic light- emitting devices (OLEDs) or as models for investigating the fluorescent structure-property relationship of the alkynyl-functionalized pyrene derivatives.

Three types of stable pyrene-based highly fluorescence (blue) compounds, 1-, 1,6-bis, 1,8-bis and 1,3,6,8-tetrakis(7-tert-butylpyrenyl)pyrenes and 1,3,6,8-tetrakis[9,9-bis(3-methylbutyl)-9H-fluoren-2-yl]pyrene, were successfully synthesized via a Pd/Cu-catalysed Suzuki cross-coupling reaction of the corresponding bromopyrenes with 7-tert-butyl-1-pyrenylboronic ester or 2-[9,9-bis(3-methylbutyl)-9H-fluoren-2-yl]-4,4,5,5-tetramethyl[1,3,2]dioxaborolane, respectively. All compounds have good solubility in common organic solvents and high thermal stability with melting points up to 270 °C; the exceptions are the isomeric 1,6-bis-, and 1,8-bispyrenyl-substituted pyrenes. All products show high extinction coefficients of absorption (λmax ≈ 349–396 nm) and high quantum yields (λmax ≈ 432–465 nm; Φf ≈ 0.75–0.99) in dichloromethane solution, and emit strong fluorescence in the visible region ranging from deep-blue to pure-blue on increasing the number of substituents. This data suggests that such systems have promise as blue emitters in organic light-emitting device (OLED) applications (OLED = organic light emitting diode). Crystal structures were determined for 1,3,6,8-tetrakis [9,9-bis(3-methylbutyl)-9H-fluoren-2-yl] pyrene and 1,3,6,8-tetrakis(4-methoxyphenyl)pyrene.

The first example of aryl-functionalized, butterfly-shaped, highly fluorescent and stable blue-emitting monomers, namely, 7-tert-butyl-1,3,5,9-tetrakis(p-R-phenyl)pyrenes, were synthesized by the Suzuki-Miyaura cross-coupling reaction from a novel bromide precursor of 1,3,5,9-tetrabromo-7-tert-butylpyrene. The crystal structures and optical and electronic properties have been investigated.

A new series of diarylamino-functionalized pyrene derivatives, namely, 1-(N,N-diarylamino)-substituted pyrenes (7), isomer of 1,6-bis- and 1,8-bis(N,N-diarylamino)-substituted pyrenes (8/9) and 1,3,6,8-tetrakis(N,N-diarylamino)-substituted pyrenes (10) have been synthesized. The structures of these synthesized compounds were determined on the basis of spectral data and elemental analysis. All compounds 7–10 have bright fluorescent emissions from sky-blue to green in solution condition (λmax = 464–500 nm in CH2Cl2) and high emission efficiency (Φf = 0.84–0.96 in dichloromethane). All compounds have high thermal stability and good solubility in common organic solvents. The electronic properties of these compounds were determined by spectroscopic methods such as UV–vis absorption spectroscopy and fluorescence emission spectroscopy. Clear evidences were obtained that the longest wavelength bands of these compounds are bathochromically red-shifted as the number of the diarylamino-substituent increased.

Using 1,3,5,9-tetrabromo-7-tert-butylpyrene as the bromide precursor, a series of novel butterfly-shaped 1,3,5,9-tetraaryl substituted pyrene derivatives were synthesized by the Suzuki–Miyaura cross-coupling reaction. Their thermal, photophysical, electrochemical and related properties were systematically investigated. All compounds were found to exhibit high thermal stabilities with decomposition temperatures (Td) of up to 300 °C. All compounds show highly blue fluorescence emissions in the spectral region of 412–469 nm in solution (Φf: 0.45–0.92) and 410–470 nm in the solid- state (Φf: 0.48–0.75). It is noteworthy that these butterfly-shaped pyrenes 4 possess low-lying HOMO levels ranging from −4.76 to −5.93 eV, which make them promising candidates in OLED applications.

A series of pyrene-based Y-shaped blue emitters, namely, 7-tert-butyl-1,3-diarylpyrenes 4 were synthesized by the Suzuki cross-coupling reaction of 7-tert-butyl-1,3-dibromopyrene with a variety of p-substituted phenylboronic acids in good to excellent yields. These compounds were fully characterized by X-ray crystallography, UV/Vis absorption and fluorescence spectroscopy, DFT calculations, thermogravimetric analysis, and differential scanning calorimetry. Single-crystal X-ray analysis revealed that the Y-shaped arylpyrenes exhibited a low degree of π stacking owing to the steric effect of the bulky tert-butyl group in the pyrene ring at the 7-position, and thus, the intermolecular π-π interactions were effectively suppressed in the solid state. Despite the significantly twisted nonplanar structures, these molecules still displayed efficient intramolecular charge-transfer emissions with clear solvatochromic shifts on increasing solvent polarity. An intriguing fact is that all of these molecules show highly blue emissions with excellent quantum yields in the solid state. Additionally, the two compounds containing the strongest electron-accepting groups, CN (4 d) and CHO (4 f), possess high thermal stability, which, together with their excellent solid-state fluorescence efficiency, makes them promising potential blue emitters in organic light-emitting device applications.

Based on the results of a retrospective review of clinical data on inpatients with ischemic colitis treated at our hospital, we created a clinical pathway and evaluated its usefulness. We used the clinical pathway for 21 inpatients, and the patient who fulfilled the criteria consisted of 18 inpatients. The fasting period after the onset and the duration of hospitalization were compared with those of 60 patients before implementation of the clinical pathway. The fasting period after the onset before and after implementation were 6.20+/- 3.42 days (mean+/- SD), and 5.28+/- 1.27 days, respectively. The duration of hospitalization before and after implementation was 10.37+/- 7.32 days, 8.37+/- 2.89 days, respectively. The clinical pathway is useful for shortening the duration of hospitalization, enhancing the uniformity of treatment and controlling the treatment risk.

Omeprazole is mainly metabolized in the liver by CYP2C19, a genetically determined enzyme, while rabeprazole is mainly nonenzymatically degraded with a minor involvement by CYP2C19. We investigated the gastric ulcer healing effect of omeprazole versus rabeprazole evaluated endoscopically with reference to the different CYP2C19 genotypes. Eighty patients with active gastric ulcer were treated with a daily dose of 20 mg of omeprazole or 10 mg of rabeprazole. The endoscopic evaluation was performed at the baseline and 2- and 8-week posttreatment periods. The endoscopic improvement of gastric ulcer size and ulcer healing rates using a thin rubber disc with a diameter of 6 mm, were evaluated in relation to the CYP2C19 genotypic status. The mean 2-week posttreatment ulcer size value by rabeprazole did not significantly differ among the different CYP2C19 genotypes, whereas the mean value in the homozygous extensive metabolizer patients treated with omeprazole was significantly (P = 0.0057) greater than in those with rabeprazole. However, after the 8-week treatment, omeprazole and rabeprazole showed the similarly high healing rates of 87.8% (31/37) and 88.9% (32/36), respectively. Although both omeprazole and rabeprazole showed a high healing rate of gastric ulcer after the 8-week treatment period, the healing effect of rabeprazole appears to be relatively independent of the CYP2C19 status, resulting in an earlier repair of gastric mucosal damage evaluated endoscopically compared to that of omeprazole.

The synthesis, crystal structures and photophysical properties of two types of pyrene-cored blue-light emitting [4]helicenes (7 and 9) are reported. The chemical structures of all synthesized compounds were fully confirmed by 1H and 13C NMR spectra, mass spectroscopy as well as elemental analysis. Single-crystal X-ray analysis of these [4]helicenes revealed that there are two types of laterally naphthalene annulated helical architectures, which are clearly influenced by different R substituents. The photophysical properties of the [4]helicenes (7 and 9) were fully investigated in both solutions and films, along with the pre-cyclization products, 4,9- and 4,10-bis(phenylethenyl)pyrenes (6 and 8). Notable optical features were obtained in these compounds, which make them promising candidates for several important applications in modern electronic and optoelectronic devices, such as blue emitters in organic light-emitting devices (OLEDs), or as models for further exploring the development of a new generation of organic materials based on pyrene.