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1.
Motoi Wadano 《Colloid and polymer science》1940,93(3):324-338
Ohne ZusammenfassungVI. Mitteilung: M. Wadano, Kolloid-Z.93, 103 (1940).Ich danke meinem Mitarbeiter T. Gohda für die Durchführung der Versuche.Herrn Dr. habil. M. Ulmann, Berlin-Dahlem, möchte ich an dieser Stelle für die freundlichen Ratschläge herzlichst danken. 相似文献
2.
We have studied the characteristic features of carbazole phosphorescence quenching by benzophenone in toluene at 77 K. We
have shown that the decrease in the relative phosphorescence intensity for carbazole (energy donor) by a greater factor than
we see for the relative change in its decay time is due to the fact that a change in the phosphorescence decay time occurs
only for carbazole molecules participating in triplet-triplet energy transfer, while the substantial decrease in the phosphorescence
intensity for carbazole with no change in the phosphorescence decay time is connected with quenching of its singlet states.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 4, pp. 554–556, July–August, 2006. 相似文献
3.
Hiroshi Suda Masatoahi Motoi Masatoshi Fujii Shigeyoshi Kanoh Hiroshi Yoshida 《Tetrahedron letters》1979,20(47):4565-4568
Enantioselective reductions of prociral ketones with chiral hydride reagent prepared from optically active 2,2′-diamino-6,6′-dimethylbiphenyl and lithium aluminum hydride were accomplished in O.Y. more than 50%. 相似文献
4.
High enantioselectivity in rhodium-catalyzed allylic alkylation of 1-substituted 2-propenyl acetates
[reaction: see text] Rhodium-catalyzed asymmetric allylic alkylation of 1-substituted 2-propenyl acetates with dimethyl malonate proceeded with high enantioselectivity in the presence of cesium carbonate as a base and a rhodium catalyst generated from Rh(dpm)(C(2)H(4))(2) (dpm = dipivaloylmethanato) and a chiral phosphino-oxazoline whose basic skeleton is axially chiral binaphthyl to give branch alkylation products in greater than 90% ee. 相似文献
5.
The palladium-catalyzed regio- and diastereo-selective allylic alkylation of allyl acetates with carbon nucleophiles occurred. The stereochemistry was highly controlled by the palladium catalyst with 2-(diphenylphosphino)benzoic acid as the ligand, and vicinal quaternary and tertiary carbon centers were constructed. 相似文献
6.
Ryosuke Matsui Erina Niijima Tomomi Imai Hiroyuki Kobayashi Akiko Hori Azusa Sato Yuko Nakamura Osamu Kitagawa 《Molecules (Basel, Switzerland)》2022,27(7)
The halogen bond has been widely used as an important supramolecular tool in various research areas. However, there are relatively few studies on halogen bonding related to molecular chirality. 3-(2-Halophenyl)quinazoline-4-thione derivatives have stable atropisomeric structures due to the rotational restriction around an N-C single bond. In X-ray single crystal structures of the racemic and optically pure N-C axially chiral quinazoline-4-thiones, we found that different types of intermolecular halogen bonds (C=S⋯X) are formed. That is, in the racemic crystals, the intermolecular halogen bond between the ortho-halogen atom and sulfur atom was found to be oriented in a periplanar conformation toward the thiocarbonyl plane, leading to a syndiotactic zig-zag array. On the other hand, the halogen bond in the enantiomerically pure crystals was oriented orthogonally toward the thiocarbonyl plane, resulting in the formation of a homochiral dimer. These results indicate that the corresponding racemic and optically pure forms in chiral molecules are expected to display different halogen bonding properties, respectively, and should be separately studied as different chemical entities. 相似文献
7.
Hironao Nakayama Masako Nakahara Erina Matsugi Midori Soda Tomoka Hattori Koki Hara Ayuki Usami Chiaki Kusumoto Shigeki Higashiyama Kiyoyuki Kitaichi 《Molecules (Basel, Switzerland)》2021,26(1)
Ferulic Acid (FA) is a highly abundant phenolic phytochemical which is present in plant tissues. FA has biological effects on physiological and pathological processes due to its anti-apoptotic and anti-oxidative properties, however, the detailed mechanism(s) of function is poorly understood. We have identified FA as a molecule that inhibits apoptosis induced by hydrogen peroxide (H2O2) or actinomycin D (ActD) in rat pheochromocytoma, PC12 cell. We also found that FA reduces H2O2-induced reactive oxygen species (ROS) production in PC12 cell, thereby acting as an anti-oxidant. Then, we analyzed FA-mediated signaling responses in rat pheochromocytoma, PC12 cells using antibody arrays for phosphokinase and apoptosis related proteins. This FA signaling pathway in PC12 cells includes inactivation of pro-apoptotic proteins, SMAC/Diablo and Bad. In addition, FA attenuates the cell injury by H2O2 through the inhibition of phosphorylation of the extracellular signal-regulated kinase (ERK). Importantly, we find that FA restores expression levels of brain-derived neurotrophic factor (BDNF), a key neuroprotective effector, in H2O2-treated PC12 cells. As a possible mechanism, FA increases BDNF by regulating microRNA-10b expression following H2O2 stimulation. Taken together, FA has broad biological effects as a neuroprotective modulator to regulate the expression of phosphokinases, apoptosis-related proteins and microRNAs against oxidative stress in PC12 cells. 相似文献
8.
The iridium-catalyzed allylic alkylation with azlactone and sequential aza-Cope rearrangement was demonstrated. The sequential reaction was effective in separating of diastereoisomers and afforded a diastereomerically pure azlactone derivative and oxazolinone derivative. 相似文献
9.
Solovieva A Vstovsky G Kotova S Glagolev N Zav'yalov BS Belyaev V Erina N Timashev P 《Micron (Oxford, England : 1993)》2005,36(6):508-518
This work is to show that activity of porphyrins in singlet oxygen generation (SOG) is determined not only by their molecular structure but also by supramolecular structure of porphyrin containing systems. This is demonstrated by results of studies of SOG in the gas phase by vacuum deposited tetraphenylporphyrin (TPP) layers under photoexcitation conditions. The structure of the layers was studied by atomic force microscopy (AFM), TEM in diffraction regime (TED) and by the flicker-noise spectroscopy (FNS) method. It was shown that substrates affect the deposited layers structure only at earlier stages of the layer formation. AFM and TED data, together with FNS quantitative parameters of TPP layers, show directly that the chemical activity of solid-phase systems can be determined not only by their chemical nature but also by their supramolecular structure. 相似文献
10.