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971.
Synthesis of the proposed structure of tyroscherin, a growth inhibitor of IGF-1-dependent cancer cells, was succeeded by one-pot Julia coupling. However, spectral data of the synthetic compound were not identical with those of natural tyroscherin. The stereochemistry of tyroscherin is revised to be 2S,3R,8R,10R by syntheses of stereoisomers. Synthetic tyroscherin showed more potent activity than its stereoisomers against IGF-1-dependent cancer cells. 相似文献
972.
Toshiki Nakata Hisashi Miyafuji Shiro Saka 《Applied biochemistry and biotechnology》2006,130(1-3):476-485
The water-soluble portion and precipitates obtained by supercritical (SC) water treatment of microcrystalline cellulose (Avicel)
were enzymatically hydrolyzed. Glucose could be produced easily from both substrates, compared with the Avicel. Therefore,
SC water treatment was found to be effective for enhancing the productivity of glucose from cellulose by the enzymatic hydrolysis.
It is also found that alkaline treatment or wood charcoal treatment reduced inhibitory effects by various decomposed compounds
of cellulose on the enzymatic hydrolysis to achieve higher glucose yields. Furthermore, glucose obtained by SC water treatment
followed by the enzymatic hydrolysis of cellulose could be converted to ethanol by fermentation without any inhibition. 相似文献
973.
974.
Takao Watanabe 《Monatshefte für Mathematik》2006,149(2):155-172
We generalize the notion of successive minima, Minkowski’s second theorem and Siegel’s lemma to a free module over a simple
algebra whose center is a global field.
The author was partly supported by the Grant-in-Aid for Scientific Research (C), Japan Society for the Promotion of Science. 相似文献
975.
976.
Chihiro Moriguchi Akihiro Ohta Chikara Egami Yoshimasa Kawata Susumu Terakawa Masaaki Tsuchimori Osamu Watanabe 《Optical Review》2006,13(4):215-217
We present an analysis of the properties of an imaging based on a near-field recording technique in comparison with simulation
results. In the system, the optical field distributions localized near the specimens are recorded as the surface topographic
distributions of a photosensitive film. It is possible to observe both soft and moving specimens, because the system does
not require a scanning probe to obtain the observed image. The imaging properties are evaluated using fine structures of paramecium,
and we demonstrate that it is possible to observe minute differences of refractive indices. 相似文献
977.
Takeshi Sakai Takehiko Yagi Ryosuke Takeda Toshiki Hamatani Yuki Nakamoto Hirokazu Kadobayashi 《高压研究》2020,40(1):12-21
ABSTRACTBoth micro-paired and conical support type double-stage diamond anvil cells (ds-DAC) were tested using a newly synthesized ultra-fine nano-polycrystalline diamond (NPD). Well-focused X-ray sub-micron beam and the conically supported 2nd stage anvils (micro-anvils) with 10?μm culet enable us to obtain good quality X-ray diffraction peaks from the sample at around 400?GPa. The relationship between confining pressure and sample pressure depends heavily on the initial height (thickness) of micro-anvils, the difference of a few micrometers leads to a quite different compression path. The conical support type is a solution to retain both enough thickness and strength of micro-anvils at higher confining pressure conditions. All conical support ds-DAC experiments terminated by the failure of the 1st stage anvil instead of 2nd one. The combination of ultra-fine NPD 2nd stage anvil and NPD 1st stage anvil opens a new frontier for measurement of the X-ray absorption spectrum above 300?GPa. 相似文献
978.
Imai Keiri Watanabe Yutaka W. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3847-3855
Journal of Radioanalytical and Nuclear Chemistry - We started monitoring the radiocesium released from Fukushima in the North Pacific surface water from May 2011 after the accident soon to June... 相似文献
979.
980.
Dr. Takumi Abe Toshiki Yamashiro Kaho Shimizu Prof. Dr. Daisuke Sawada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(37):e202201113
This work reports the novel reactivity of hemiaminal as a precursor for indole editing at the multi-site. The HFIP-promoted indole editing of indoline hemiaminals affords 2-arylindoles through a ring-switch sequence. The key to success of this transformation is to use a cyclic hemiaminal as an α-amino aldehyde surrogate under transient tautomeric control. This transformation features mild reaction conditions and good yields with broad functional group tolerance. The utility of this transformation is presented through the one-pot protocol and the synthesis of isocryptolepine. 相似文献