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Xanthones and acridones were synthesized from 3,4-difluoronitrobenzene and 2-fluorobenzaldehydes in two or three steps. The key step was nucleophilic aroylation catalyzed by imidazolidenyl carbene. The nucleophilic aroylation of 3,4-difluoronitrobenzene afforded 2,2'-difluoro-4-nitrobenzophenones. The cyclization of the difluorobenzophenones with O-nucleophile and N-nucleophile yielded 3-nitroxanthones and 3-nitroacridones, respectively. Indazole, quinolino[2,3-b]quinoxaline, and thianaphtho[2,3-b]quinoxaline derivatives were also synthesized via nucleophilic aroylation of 2,3-dichloroquinoxaline followed by cyclization with nucleophiles.

Copper nanoparticles (Cu NPs) were produced through photoreduction of a mixture of copper acetate solution and carbon nanotubes (CNTs) at room temperature. The diameter of the NPs could be controll...

The beneficial effects of high-monounsaturated fat (high-MUFA) diets on diabetic patients have been reported, whereas studies concerning the effects on animals have been few. Although experiments on animals should be useful in elucidating underlying mechanisms, it is not clear even whether there are benefits of a high-MUFA diet in animals. This study examined the short-term effects of a high-MUFA diet on normal and genetically diabetic mice. The high-MUFA diet supplied 38% of the total calories as fat (26% from MUFA), while a regular diet was 13% fat (3% from MUFA). Normal C5 7BL/6J and diabetic C57BL/KsJ-db/db mice were fed either the regular or the high-MUFA diet for 1 wk. Serum glucose and lipid levels were then measured. In normal mice, hepatic triglyceride production was also compared between the two dietary groups using the Triton WR1339 method. An oral glucose tolerance test was conducted on the diabetic mice. After 1 wk of feeding to normal mice, the high-MUFA diet was seen to lower serum triglyceride levels and reduce hepatic triglyceride production in comparison with the regular diet; it is suggested that the lowering of triglyceride consists of mechanisms including reduced hepatic triglyceride production. When diabetic mice were fed the high-MUFA diet with a controlled caloric intake, the serum glucose levels lowered without an accompanying deterioration in lipid metabolism and the impaired glucose tolerance was ameliorated. This study demonstrates that a high-MUFA diet can lower serum triglyceride levels in normal mice and improve disorders of glucose metabolism in diabetic mice.

Objectives and background : Nocturnal apnea and hypoxia are implicated in the pathogenesis of pulmonary and systemic hypertension in obstructive sleep apnea syndrome (OSAS). We have hypothesized that vasodilating factors including nitric oxide (NO) are affected by nocturnal apnea and hypoxia in patients with OSAS. Method : We examined the serum level of NO production in 24 patients with OSAS (mean age 54.2±7.9 years) and 24 age-matched control subjects (53.4±8.1 years) and tested the effects of oxygen administration on the production of NO in the patients. Results : The serum level of nitrite/nitrates (NO x ), which are stable metabolites of NO, was lower in patients with OSAS than in control subjects. Administration of 1–2 l/min of oxygen during night increased the patients' NO x level from 35.6±7.3 to 57.8±11.6 μM. Compressed air administration did not affect the NO x level in the patients. Conclusion : These results indicate that systemic NO production is impaired in OSAS patients, possibly due to nocturnal hypoxia.

New muq-opioid receptor (MOR) agonists containing 4-hydroxypiperidine, piperidine and piperazine moieties were synthesized and evaluated to find a peripheral opioid analgesic. Among the synthesized compounds, 12-[1-[3-(N,N-dimethylcarbamoyl)-3,3-diphenylpropyl]-4-hydroxypiperidin-4-yl]phenoxy]acetic acid (8: SS620) having phenoxyacetic acid and 4-hydroxypiperidine moieties showed the highest agonist potency on the MOR in an isolated guinea-pig ileum preparation, and it also had selectivity to the human MOR expressed in Chinese hamster ovary (CHO)-K1 cells compared with the same types of delta- and kappa-opioid receptors (DOR and KOR). In addition, compound 8 showed a 10 times more potent MOR agonist activity than loperamide. Furthermore, compound 8 showed a peripheral analgesic activity in vivo screening on rat.

We have measured the temperature dependence of the absorption spectra in the band-edge region and the reflection spectra of the (CH 3 NH 3 ) 3 M 2 Br 9 (M:Sb,Bi) single crystals exhibiting serveral successive phase transitions. The dispersion-like reflection structure due to the band-edge exciton transition is observed at 2.92 eV and 2.95 eV for (CH 3 NH 3 ) 3 Bi 2 Br 9 and (CH 3 NH 3 ) 3 Sb 2 Br 9 , respectively. The reflection structure remains even at room temperature reflecting a large binding energy. The fundamental absorption edge in both crystals possesses an exponential shape following the empirical Urbach rule. The steepness coefficients characterizing a broadening of the absorption edge exhibit a distinct jump at the phase transition temperature. The results indicate that the ordering of orientational motion of methylammonium cations changes not only the crystal structure and dielectric properties but also the Urbach tail in both crystals.

We investigated the phase transitions in the (CH3NH3)3Bi2(1−x)Sb2xBr9 mixed crystal system. The concentration-temperature phase diagram was made on the basis of the result of dielectric measurements. The triple point was found at 32 mol% and 107 K in the phase diagram.

In the presence of 1, 3-dimethylimidazolium iodide (1), 6-chloro-9-phenyl-9H-purine (7) and 4-chloro-5, 6-dimethylpyrrolo[2, 3-d]pyrimidines 40-42 undrwent uncleophilic aroylation with arenecarbaldehydes (5) to give the corresponding fused aroylpyrimidines 8 and 43-45. 1, 3-Dimethylbenzimidazolium iodide (2) was an effective catalyst for the similar synthesis of 7-aroyl-3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidines 16-21. In the synthesis of 4-aroyl-1H-pyrazolo[3, 4-d]pyrimidines 26-32, both azolium salts 1 and 2 were effective as catalysts. Moreover, 4-aroyl-7H-pyrrolo[2, 3-d]pyrimidines 43-45 were obtained in good yields via the 4-tosyl derivatives, in the presence of catalytic amounts of sodium p-toluenesulfinate (46) and the imidazolium salt 1. This catalytic aroylation was found to be a facile and useful method for the synthesis of 6-aroyl-9H-purines and their analogues.

4-(α-Benzyl-α-hydroxybenzyl)quinazoline (4a) underwent retro-benzoin condensation catalyzed by cyanide ion to give deoxybenzoin (2a) and quinazoline (5a). Similarly, several nitrogen-containing heteroarenes (4, 9, 12, 16-19) having an α-hydroxybenzyl group at the α-position of the nitrogen underwent retro-benzoin type condensation to afford ketones (2) and heteroarenes (5). However, similar reaction of pyrazolopyrimidines (13, 14, 15) having an α-benzyl-α-hydroxybenzyl group resulted in benzyl migration, giving benzylpyrazolopyrimidines (8) and arenecarbaldehydes (3). Tetrabutylammonium cyanide (11, Bu 4 NCN) was a more effective cyanide ion donor than KCN (10). The retro-benzoin condensation was applied to the synthesis of 2-substituted quinazolines (38) from 2-chloro-4-aroylquinazolines (34), using the aroyl group as a protecting and electron-withdrawing group.

When α-benzylbenzoin (3a, α-benzyl-α-hydroxybenzyl phenyl ketone) was treated with potassium cyanide (1) in N, N-dimethylformamide at 80°C for 1 h, the carbon-carbon bond was cleaved, resulting in the formation of deoxybenzoin (4a, benzyl phenyl ketone) and benzaldehyde (2a). This carbon-carbon bond cleavage proceeds through a retro-benzoin condensation mechanism. This mothod of synthesizing ketones was applied to several α-substituted benzoins (3), and the corresponding ketones (4) were formed in good yields. Further, we found that the cyanide ion-donating ability of tetrabutylammonium cyanide (6, Bu4NCN) is more effective than that of potassium cyanide (1, KCN). As expected from the chemical analogy between cyanide ion and azolium ylide, serveral azolium salts (7) can also be employed in the retro-benzoin condensation as catalysts.The benzoin derivatives 3 were synthesized in the following three ways; reaction of alkyl halide (9) with benzoin (5), Michael addition of benzoin (5) with acceptors (10), and Grignard reaction of benzils (8). Alkylation of the benzoins without isolation, followed by carbon-carbon bond cleavage, readily afforded the corresponding ketones (4).

The treatment of 1, 3-dimethyl-2-(α-benzyloxybenxyl)benzimidazolium iodides 1 with a base gave deoxybenzoins 2 in moderate yields. Sodium hydride (NaH), potassium carbonate (K2CO3), and cesium carbonate (Cs2CO3) were effective bases in this reaction. Deoxybenzoins 2 were produced through rearrangement of the benzyl group followed by expulsion of the 1, 3-dimethylbenzimidazolium ylide (A). The rearrangement proceeds in a way similar to Witting rearrangement. Deoxybenzoins 2 were also formed in good yields from 1, 3-dimethyl-2-(α-benzyloxybenxyl)-imidazolium iodides 4 upon similar treatment. However, the quaternary salts having a thiazolium moiety 5a and a pyridinium moiety 6a failed to produce deoxybenzoin (2a).

Tooth-shaped titanium implants were placed into a tooth socket with adhering periodontal ligament after extraction to examine the regeneration of periodontal tissues from remaining periodontal ligament cells. The extraction forces of the implants were measured with a materials testing machine. The mechanical strength of the peri-implant ligament increased markedly from 14 (25% of control) to 28 (68% of control) days. The implants and surrounding tissues were observed morphologically. The result showed that cementum-like hard tissues were formed on the surface of the titanium implants and there were many collagen fiber bundles between the cementum-like tissues and alveolar bone at 21 and 28 days. These findings suggest that placement of an implant into a socket with periodontal ligament leads to formation of new cementum-like hard tissues with functionally-oriented collagen bundles and development of adequate mechanical strength.

Background: Sleep apnea syndrome (SAS) is an independent risk factor for hypertension which is a major risk factor for acute aortic dissection. The purposes of this study were to assess the prevalence of SAS in patients with acute aortic dissection, delineate the characteristics of patients who have acute aortic dissection with SAS. Methods: Of 95 consecutive patients with acute aortic dissection, 13 had episodes of sleep apnea and nocturnal hypoxemia. A portable sleep monitoring system was used to assess sleep status in the 13 patients. Results: The SAS-positive group consisted of 12 patients (12.6%), 8 with type A dissection and 4 with type B dissection. Age was significantly lower in the SASpositive group (47.2 ± 8.5 years) than in the SAS-negative group (64.9 ± 10.3 years) (p

In the reaction of 1-substituted phthalazines with ynamines, there are three patterns of ring transformation, giving naphthalene derivatives through addition-cyclization-denitrogenation (type A), giving benzodiazocine derivatives through addition-cyclization-ring expansion (type B), and giving penta-substituted pyridine derivatives through N-N bond cleavage of the pyridazine ring (type C). In these reactions, it is considered that the substituent group at the 1-position of the phthalazine ring is a significant factor determining the outcome.

Graphene was used as the topmost electrode for a metal-oxide-semiconductor planar-type electron emission device. With several various layers, graphene as a gate electrode on the thin oxide layer was directly deposited by gallium vapor-assisted chemical vapor deposition. The maximum efficiency of the electron emission, defined as the ratio of anode current to cathode current, showed no dependency on electrode thickness in the range from 1.8 nm to 7.0 nm, indicating that electron scattering on the inside of the graphene electrode is practically suppressed. In addition, a high emission current density of 1–100 mA/cm2 was obtained while maintaining a relatively high electron emission efficiency of 0.1%–1.0%. The graphene-oxide-semiconductor planar-type electron emission device has great potential to achieve both high electron emission efficiency and high electron emission current density in practical applications.

trans-Pt(CH2CMe2Et)Br(PPh3)2 induced C-H bond activation of CH4 under UV p irradiation leading to trans-PtMeBr(PPh3)2, while H-D exchange reaction of CH4 with D2 or D2SO4 took place in the photochemical reaction system containing Pt(PPh3)4 and neohexyl bromide. A possible reaction mechanism involving radical process is discussed on the basis of radical-trap experiment.

Facile sp 3 CH bond activation of toluene, p -xylene and mesitylene, was photochemically promoted by trans -Pt(CH 2 CMe 2 Et)Br(PPh 3 ) 2 leading to trans -Pt(CH 2 Ar)Br(PPh 3 ) 2 quantitatively, while regioselective sp 3 CH bond cleavage at the benzylic position of ethylbenzene and cumene readily took place to yield styrene and α-methylstyrene, respectively. A possible reaction mechanism involving radical process is discussed on the basis of isotope and radical-trap experiments.

1-Chlorophthalazine (1) reacts with a 2-fold molar excess of ynamines 2a, b to give penta-substituted pyridine derivatives 3a, b by nitrogen-nitrogen bond cleavage of the pyridazine ring with release of hydrogen chloride. Similarly, other fused pyridazines having a chloro substituent α to nitrogen in the pyridazine ring, i.e., pyrido[3, 4-d]- (10a), pyrido[2, 3-d]- (10b), thiazolo[4, 5-d]- (10c, d), furo[2, 3-d]- (10e) and pyrrolo[2, 3-d]- (10f, g) pyridazine derivatives, gave the corresponding penta-substituted pyridines 11a-11k.

The ability of 1, 3-dimethylimidazolium iodide (1) to catalyze the aroylation of the chloroheteroarenes 4-8 with arenecarbaldehydes 3 as sources of the aroyl groups was examined in order to develop a preparative method of aroylheteroarenes. In the presence of 1, the treatment of the 4-chloroquinazolines (4 : 2-H, 5 : 2-Me, 6 : 2-Ph) with arenecarbaldehyde 3 in refluxing THF (tetrahydrofuran) or dioxane led to the 4-aroylquinazolines (9 : 2-H, 10 : 2-Me, 11 : 2-Ph) in excellent yields, as had been found with 1, 3-dimethylbenzimidazolium iodide (2). Similar reaction of the 4-chloro-1H-pyrazolo[3, 4-d]pyrimidines (7 : 1-Ph, 8 : 1-Me) with arenecarbaldehyde 3 yielded the corresponding 4-aroyl-1H-pyrazolo[3, 4-d]pyrimidines (12 : 1-Ph, 13 : 1-Me). Compound 1 seems to catalyze the aroylation of a wider range of arenecarbaldehydes 3 as compared with 2.

Newly prepared [RuX(p-cymene)(bichep)]X, (X = I, Cl) and Ru(OAc) 2 (bichep) (bichep = 2,2′-bis(dicyclohexylphosphino)-6,6′-dimethyl-1,1′-biphenyl) proved to be highly efficient catalysts for asymmetric hydrogenation of carbonyl compounds bearing phenylglyoxyloyl group under mild conditions.

A series of novel negative photochromic poly(methyl methacrylate) having spirobenzoselenazolinobenzopyran side groups was newly synthesized, and their reversible photochemical color changes were studied: their metastable colorless spiro-forms induced by Vis light irradiation was stabilized more than 90 days, although that dispersed in polymer film was thermally unstable turning to the stable merocyanine-form. Kinetic study to investigate their thermocoloration process was performed.

A series of photochromic 6′-nitro-3-octadecylspirobenzoselenazolinobenzopyrans have been newly prepared and their solution structures of the colored form have been confirmed as 3-octadecylbenzosele...

2-Quinolyl thiocyanate (2) was found to react with C-nucleophiles, i.e., phenylacetonitrile, p-chlorophenylacetonitrile, p-cyanophenylacetonitrile, p-methoxyphenylacetonitrile, ethyl cyanoacetate, and malononitrile, in two ways, depending on the nature of the reagent. The more reactive phenylacetonitrile carbanions attacked at the less reactive sulfur atom, which is less subject to steric effect compared with the 2-position carbon of 2, to give the corresponding sulfides (α-(2-quinolylthio)phenyl- (8), α-(2-quinolylthio)-4-chlorophenyl- (9), α-(2-quinolylthio)-4-cyanophenyl- (10), and α-(2-quinolylthio)-4-methoxyphenylacetonitrile (11)). The less reactive ethyl cyanoacetate and malononitrile carbanions attacked at the more reactive 2-position carbon of 2 to afford the corresponding ipso-substitution products (α-cyano-2-quinolineacetate (4) and 2-quinolinemalononitrile (7)). However, in the reaction of diethyl malonate carbanion, diethyl 2-quinolinemalonate (12) was not obtained, presumably for steric reasons.

A [4+2]-cycloaddition of quinazoline (2) and the 3H-1, 2, 3-triazolo[4, 5-d]pyrimidine 4 with enamines 1a-e resulted in ring transformation into the quinolines, 3a and 3c, and the 3H-1, 2, 3-triazolo[4, 5-b]pyridines, 5a-e, respectively. Similarly, the ynamine 13a cycloadded to 2 and its 4-cyano derivative 6, giving the quinolines, 14a and 14b, respectively.On the other hand, the 3H-1, 2, 3-triazolo[4, 5-d]pyrimidines 4, 15, 8, 16, 17, 18, and 19 underwent [2+2]-cycloaddition with the ynamine 13a, resulting in ring transformation into the corresponding 3H-1, 2, 3-triazolo[4, 5-d]-[1, 3]diazocines 21a-27. The 7-methoxy derivative 20, the 4-methoxy- and 4-cyano-1H-pyrazolo[3, 4-d]pyrimidines, 30 and 31, and the 6-cyano-9H-purine 36 also underwent [2+2]-cycloaddition with 13a to give the corresponding 3H-1, 2-3-triazolo[4, 5-b][1, 5]diazocine 28, 1H-pyrazolo[3, 4-b][1, 5]diazocines, 32 and 33, and 3H-imidazo[4, 5-b]-[1, 5]diazocine 37, respectively.The structures of the 1, 3- and 1, 5-diazocines, 21a and 28, were determined by X-ray crystallography.

Chiral cationic and neutral Rh complexes RhX(bichep)(nbd) (XCl,ClO 4 ; nbd=norbornadiene;bichep=2,2′-bis(dicyclohexylphosphino)-6,6′-dimethyl-1,1′-biphenyl) are highly active and excellent catalysts for enantioselective hydrogenation of prochiral olefins and ketones under mild reaction conditions.

Photochromic spiroindolinobenzothiopyrans having a methacryloxymethyl group have been prepared and their colored forms were demonstrated to be a zwitterionic structure on the basis of the spectroscopic data.

A series of bis(tertiary phosphine)(alkylphenylketene)nickel complexes, Ni[(C 6 H 5 (R)CCO)L 2 [R  CH 3 ( a ), C 2 H 5 ( b ); L  P(C 6 H 5 ) 3 ( 1 ), P(C 6 H 5 ) 2 ( p -CH 3 C 6 H 4 ) ( 2 )], were isolated from the reaction of bis(1,5-cyclooctadiene)nickel with alkylphenylketene in the presence of the corresponding tertiary phosphines. The spectroscopic analyses of 1 and 2 suggest η 2 -(C,O) to be a ketene structure close to the structure of oxanickelacyclopropane. Based on their chemical reactivities and fluxional behaviors in 1 H and 13 C NMR, the ketene moieties of 1 and 2 switch their coordination-mode from η 2 -(C,O) to η 2 -(C,C) type via an associative process involving binuclear μ-ketene intermediates prior to undergoing further reactions.

The treatment of 4-chloroquinazoline (1) with arylmagnesium bromide (3) in tetrahydrofuran (THF) resulted in the formation of 2-arylme- thyleneaminobenzonitrile (2). Continued reaction of ring opening of (1) and subsequent hydrolysis of the products (2) afforded the corresponding arenecarbaldehydes (4)

Treatment of several 1, 3-dimethyl-2-(α-benzyloxybenzyl)benzimidazolium iodides 1 with K2CO3 gave deoxybenzoins 2 in moderate yields. Deoxybenzoins 2 were produced through rearrangement of benzyl groups followed by expulsion of 1, 3-dimethylbenzimidazolium ylide (4). The reaction is classified as a Witting rearrangement.