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31.
The crystal structure of the title compound was determined (crystal data at 143 K: triclinic, space group P−1, Z=4, a=9.538(2) Å, b=11.638(2) Å, c=14.473(2) Å, α=88.647(3)°, β=89.875(3)°, γ=83.835(3)°, V=1596.9(4) Å3). In the crystal there exist two kinds of tetrameric O–HO hydrogen-bond (H-bond) systems that are quite similar to each other. The oxygen atoms accept also intermolecular C–HO H-bonds. The two types of the H-bonds connect the molecules to an infinite two-dimensional supramolecular unit, the stacking of which is aided by an intermolecular C–Hπ H-bond. A phase transition with ΔHt=4.4±0.1 kJ/mol was found at around 420 K. 相似文献
32.
The preparation of methyl 2‐methylazulene‐1‐carboxylate (1) was carried out in the presence of molecular sieves to obtain a good yield. The product was subjected to bromination under different reaction conditions to obtain methyl 1‐bromo‐2‐methylazulene‐1‐carboxylate (2) and methyl 1‐bromo‐2‐(bromomethyl) azulene‐1‐carboxylate (3). 相似文献
33.
A Koizumi K Yamano T Tsuchiya F Schweizer F Kiuchi N Hada 《Molecules (Basel, Switzerland)》2012,17(8):9023-9042
Stereocontrolled syntheses of biotin-labeled oligosaccharide portions containing the Galβ1-3GalNAc core of the TES-glycoprotein antigen obtained from larvae of the parasite Toxocara and their analogues have been accomplished. Trisaccharides Fuc2Meα1-2Gal4Meβ1-3GalNAcα1-OR (A), Fucα1-2Gal4Meβ1-3GalNAcα1-OR (B), Fuc2Meα1-2Galβ1-3GalNAcα1-OR (C), Fucα1-2Galβ1-3GalNAcα1-OR (D) and a disaccharide Fuc2Meα1-2Gal4Meβ1-OR (E) (R = biotinylated probe) were synthesized by block synthesis using 5-(methoxycarbonyl)pentyl-2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl-(1?3)-2-azide-4-O-benzyl-2-deoxy-α-D-galactopyranoside as a common glycosyl acceptor. We examined the antigenicity of these five oligosaccharides by enzyme linked immunosorbent assay (ELISA). Our results demonstrate that the O-methyl groups in these oligosaccharides are important for their antigenicity and the biotinylated oligosaccharides A, B, C and E have high serodiagnostic potential to detect infections caused by Toxocara larvae. 相似文献
34.
Single-step sol–gel deposition was attempted for realizing submicron thick, (001) oriented Pb(Zr0.53Ti0.47)O3 (PZT) thin films, using an alkoxide solution containing polyvinylpyrrolidone (PVP). A solution of molar composition, Pb(NO3)2:Zr(OC3H7
n)4:Ti(OC3H7
i)4:PVP:H2O:CH3COCH2COCH3:CH3OC2H4OH:C3H7
nOH = 1.1:0.53:0.47:0.5:5:0.5:22:0.98, was prepared as a coating solution. Gel films were prepared on Pt(111)/TiO2/SiO2/Si(100) substrates by spin-coating, and calcined at 350 °C and annealed at 650 °C either in an electric furnace or in a near-infrared
(IR) furnace. When calcined in the near-IR furnace, the films became (001) oriented on annealing. When calcined in the electric
furnace, on the other hand, the films became randomly oriented on annealing. These observations indicate that the heating
the gel films from the substrate side in the calcination step at 350 °C induces crystallographic orientation in the annealing
step at 650 °C. The effects of the heating methods on the thermal decomposition of the gel films, and the microstructure and
dielectric properties of the fired films were studied. Finally 0.4 μm thick, (001) oriented PZT films could be successfully
prepared by non-repetitive, single-step deposition. The oriented film thus obtained had the remnant polarization 2P
r of 39 μC/cm2 and the dielectric constant ε′ of 960 ± 169. 相似文献
35.
Zhi-Hong Li Zhong-Tian Jin Bing-Zhu Yin Kimiaki Imafuku 《Journal of heterocyclic chemistry》1987,24(3):779-783
3-Acetyltropolone ( 1 ) reacted with bromine, iodine, and nitric acid to afford respectively 3-acetyl-5,7-di-bromotropolone ( 2 ), 3-acetyl-7-iodotropolone ( 3 ), and 3-acetyl-5-nitro- ( 4 ) and 3-acetyl-5,7-dinitrotropolone ( 5 ). Azo-coupling reactions of 1 gave 3-acetyl-5-arylazotropolones 7a-f. The Schmidt reactions of 2 and 3 gave respectively 5,7-dibromo- ( 9 ) and 7-iodo-2-methyl-8H-cyclohept[d]oxazol-8-one ( 10 ), while 4 gave 3-acetamido-5-nitrotropolone ( 11 ). Compounds 2 and 4 reacted with hydroxylamine to give 3-methyl-8H-cyclohept[d]isoxazol-8-ones 12 and 13. The reactions of 2 , 3 , and 4 with hydrazine gave 3-methyl-1,8-dihydrocycloheptapyrazol-8-ones 15 , 16 , and 17. 相似文献
36.
The haloform reaction of 3-acetyltropolone ( 1 ) afforded 3-carboxytropolone ( 2 ) which was treated with diazomethane to give 2-methoxy-3-methoxycarbonyltropone (3a) and 2-methoxy-7-methoxycarbonyltropone (3b). The tropolone 2 reacted with hydrazine to afford 2-hydrazino-3-hydrazinocarbonyltropone ( 10 ) or 2-hydrazinotropone ( 11 ), depending on the reaction time. The reaction of 2 with phenylhydrazine produced 3-hydroxy-1-phenyl-1,8-dihydrocycloheptapyrazol-8-one (14). The treatment of 2-methoxy-3-methoxycarbonyltropone (3a) with hydrazine or phenylhydrazine gave cyclization products 12 and 15 , respectively. The reaction of 2-methoxy-7-methoxycarbonyltropone (3b) with hydrazine, phenylhydrazine, or methylhydrazine gave 2-hydrazino- ( 13 ), 2-(2-phenylhydrazino)- ( 16 ), and 2-(2-methylhydrazino)-7-methoxycarbonyltropone ( 17 ), respectively. 相似文献
37.
3-(2-Bromoacetyl)tropolone ( 1 ) reacted with several benzaldehydes 2a-e to afford 2-arylidene-3,8-dihydro-2H-cyclohepta[b]furan-3,8-diones 3a-e in very good yields. 相似文献
38.
The synthesis of 3'-deoxycapsanthin (1) and 3,4-didehydroxy-3'-deoxycapsanthin (2), carotenoids of paprika, has been achieved by employing Lewis acid-promoted regio- and stereoselective rearrangement of the C(15)-epoxy dienal 5a. The absolute stereochemistry of the newly formed C-5 chiral center of rearrangement product 6a was determined to be (R) from its alternative synthesis derived from (+)-(R)-camphonanic acid (11). 相似文献
39.
Kimiaki Sait 《Chaos, solitons, and fractals》2001,12(14-15)
In this paper we give stochastic processes generated by powers of the Lévy Laplacian acting on a space of generalized white noise distributions using stable processes. 相似文献
40.
Kimiaki Saitô 《随机分析与应用》2013,31(3):567-584
In this paper, we discuss a (C o)-group generated by the Lévy Laplacian acting on a domain in the space of Hida distributions. We also give a relationship between the analytic extension of this (C o)-group and the adjoint operator of an infinite dimensional Fourier-Mehler transform introduced by H.- H. Kuo 相似文献