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111.
Yoshikazu Shizuri Jiro Ohtsuka Seiji Kosemura Yukimasa Terada Shosuke Yamamura 《Tetrahedron letters》1984,25(48):5547-5550
Some macrocyclic diterpenes derived from euphohelioscopin A and euphornin have been stereoselectively converted into the jatropholane- and daphnane-type compounds and the known tricyclic compound which has been treated with phCOCl - pyridine to afford euphohelionone, the new type of diterpene isolated from euphorbia helioscopia L. 相似文献
112.
Steven Altschuler Sigurd B. Angenent Yoshikazu Giga 《Journal of Geometric Analysis》1995,5(3):293-358
In this paper, we study generalized “viscosity” solutions of the mean curvature evolution which were introduced by Chen, Giga,
and Goto and by Evans and Spruck. We devote much of our attention to solutions whose initial value is a compact, smooth, rotationally
symmetric hypersurface given by rotating a graph around an axis. Our main result is the regularity of the solution except
at isolated points in spacetime and estimates on the number of such points. 相似文献
113.
Nobuo Tanaka Jun Yamasaki Shingo Fuchi Yoshikazu Takeda 《Microscopy and microanalysis》2004,10(1):139-145
In(x)Ga(1-x)As quantum dots in GaP(100) crystals prepared by the OMVPE technique are observed along the [011] direction with a newly developed 200-kV spherical aberration(Cs)-corrected HRTEM, a 200-kV annular dark-field (ADF)-STEM, and a 200-kV conventional HRTEM equipped with a thermal field-emission gun. The dots are 6-10 nm in size and strongly strained due to the misfit of about 9% with the GaP substrate and GaP cap layer. All of the cross-sectional high-resolution electron micrographs show dumbbell images of Ga and P atomic columns separated by 0.136 nm in well-oriented and perfect GaP areas, but the interpretable images are limited to those taken with the Cs-corrected HRTEM and ADF-STEM with Fourier filtering of the images. The Cs-corrected HRTEM and ADF-STEM are comparable from the viewpoint of interpretable resolution. A detailed comparison between the Cs-corrected HRTEM images and the simulated ones with electron incidence tilted by 1 degree to 5 degrees from the [011] zone axis gives information on local lattice bending in the dots from the images around 0.1 nm resolution. This becomes one of the useful techniques newly available from electron microscopy with sub-angstrom resolution. 相似文献
114.
Furusawa M Tanaka T Ito T Nakaya K Iliya I Ohyama M Iinuma M Murata H Inatomi Y Inada A Nakanishi T Matsushita S Kubota Y Sawa R Takahashi Y 《Chemical & pharmaceutical bulletin》2005,53(5):591-593
Fourteen flavonol glycosides including two new compounds were isolated from the leaves of two Diospyros plants (D. cathayensis and D. rhombifolia). The structures of isolated compounds were determined by spectroscopic analysis. The scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical of the isolated compounds was also investigated. 相似文献
115.
Hideo Kigoshi Makoto Ojika Yoshikazu Shizuri Haruki Niwa Kiyoyuki Yamada 《Tetrahedron letters》1982,23(51):5413-5414
From a red alga (10, 11)-(+)-squalene-10, 11-epoxide was isolated and its asymmetric synthesis has been achieved starting from -farnesol. 相似文献
116.
117.
The phase diagrams of hexadecyl polyoxyethylene ether (C16POE10)/water/synthetic perfume, and sodium dodecyl sulfate (SDS)/water/synthetic perfume ternary systems were prepared. The synthetic perfumes used are, d-limonene, -hexylcinnamaldehyde, -ionone, benzyl acetate, linalool, and eugenol. In a series of C16POE10/water/synthetic perfume ternary systems, as the hydrophilicity of synthetic perfume increases, the regions of normal and inverse micellar solution phases were found to be extended, while that of the lamellar liquid crystal phase was reduced. Moreover, every region of normal micellar solutions, inverse micellar solutions, and lamellar liquid crystal phases in SDS/water/synthetic perfume ternary systems was found to be smaller than those in C16POE10/water/synthetic perfume systems. 相似文献
118.
D. F. Calhane C. M. Alber J. Ludmila B. G. Šimek V. Kohlschütter H. Schödl P. Jacquet M. Giordani H. Kiyota J. Guzmán A. Ranmcaño C. G. Donova B. Jones M. G. Raeder R. Höiors L. Lucchi A. Bartocci W. Moldenhauer N. Isgarischew A. F. Prede G. Illari G. Damany J. Heyrovský D. Ilkovič G. Semerano I. Slendyk G. Devoto A. Ratti H. Mandai S. Zeltzer G. Kimura M. Tokuoka I. Smolér R. Brdička A. Scheicher 《Analytical and bioanalytical chemistry》1934,96(5-6):193-209
119.
To demonstrate the neighbouring-group participation of the 2-benzyloxy group in the glycosidation of phenols and of strongly acidic alcohols by the diazirine 1 , we examined the glycosidation of 4-nitrophenol, 4-methoxyphenol, (CF3)2CHOH, MeOH, and i-PrOH by the diazirine 11 , derived from the 2-deoxypyranose 6 . Oxidation of the oximes 7 yielded (E)- and (Z)- 8 . In solution, (E)- 8 isomerised to (Z)- 8 . Similarly, the (E)-configurated mesylate 9 , prepared from 8 , underwent acid-catalysed isomerisation to (Z)- 9 . Treatment of (Z)- 9 with NH3, followed by oxidation of the resulting diaziridine 10 with I2, yielded the desired diazirine 11 . Glycosidation by 11 of the above mentioned hydroxy compounds yielded the glycosides 12–21 . In agreement with the postulated neighbouring-group participation, these glycosidation proceeded without, or with a very low diastereoselectivity, favouring the axial anomers. 相似文献
120.
Treatment of thiol esters 1 with zinc reagent 2 in the presence of a small amount (相似文献