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41.
Midori O. Ishitsuka Hidefumi Nikawa Takahiro Tsuchiya Michael T.H. Liu 《Tetrahedron letters》2007,48(5):859-861
By employing C60 as a chemical probe, the photolysis of benzylchlorodiazirine has been proposed to form carbene and the rearranged products via the excited state. 相似文献
42.
Hidefumi Yoshii Aya Sakane Daisuke Kawamura Tze Loon Neoh Hayato Kajiwara Takeshi Furuta 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):591-596
The release kinetics of (−)-menthol from chewing gum was investigated using various encapsulated powder of (−)-menthol. The
apparatus of flavor release of chewing gum was made with a glass container of mashing homogenizer. Flavor release behavior
could be correlated with Avrami’s equation. Chewing gum containing (−)-menthol/γ-CD complex powder had longer retention of
(−)-menthol compared with the β-CD complex powder and the (−)-menthol encapsulated in modified starches. The activation energies
of (−)-menthol release from chewing gum were 106 kJ/mol for γ-CD complex and 74 kJ/mol for (−)-menthol/β-CD complex powder
and emulsified (−)-menthol encapsulated in HI-CAP, respectively. 相似文献
43.
(E)‐,(Z)‐Parallel Preparative Methods for Stereodefined β,β‐Diaryl‐ and α,β‐Diaryl‐α,β‐unsaturated Esters: Application to the Stereocomplementary Concise Synthesis of Zimelidine
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Yuichiro Ashida Yuka Sato Takeyuki Suzuki Kanako Ueno Ken‐ichiro Kai Dr. Hidefumi Nakatsuji Prof. Dr. Yoo Tanabe 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(15):5934-5945
Parallel and practical methods for the preparation of both (E)‐ and (Z)‐β‐aryl1‐β‐aryl2‐α,β‐unsaturated esters 1 and (E)‐ and (Z)‐α‐aryl1‐β‐aryl2‐α,β‐unsaturated esters 2 are described. These methods involve accessible, robust, stereocomplementary N‐methylimidazole (NMI)‐mediated enol tosylations (14 examples, 70–99 % yield), as well as stereoretentive Suzuki–Miyaura cross‐couplings (36 examples, 64–99 % yield). The highlighted feature of the present protocol is the use of parallel and stereocomplementary approaches to obtain highly (E)‐ and (Z)‐pure products 1 and 2 by utilizing sequential enol tosylations and cross‐coupling reactions. An expeditious and parallel synthesis of (E)‐ and (Z)‐zimelidine ( 3 ), which is a highly representative selective serotonin reuptake inhibitor (SSRI), was performed by utilizing the present methods. 相似文献
44.
Akasaka T Lu X Kuga H Nikawa H Mizorogi N Slanina Z Tsuchiya T Yoza K Nagase S 《Angewandte Chemie (International ed. in English)》2010,49(50):9715-9719
45.
46.
Wakahara T Nikawa H Kikuchi T Nakahodo T Rahman GM Tsuchiya T Maeda Y Akasaka T Yoza K Horn E Yamamoto K Mizorogi N Slanina Z Nagase S 《Journal of the American Chemical Society》2006,128(44):14228-14229
We show here that La@C72 has a non-IPR cage, unique electronic properties, and high reactivity by the spectroscopic and X-ray crystallographic analysis and the theoretical study. The isolation of La@C72 as a stable derivative might constitute an important stepping-stone on the way to isolation of these unknown metallofullerenes and open new material science of metallofullerenes. 相似文献
47.
Satoshi Aoki Takayuki Hibi Hidefumi Ohsugi Akimichi Takemura 《Annals of the Institute of Statistical Mathematics》2010,62(2):299-321
We consider testing independence in group-wise selections with some restrictions on combinations of choices. We present models for frequency data of selections for which it is easy to perform conditional tests by Markov chain Monte Carlo (MCMC) methods. When the restrictions on the combinations can be described in terms of a Segre–Veronese configuration, an explicit form of a Gröbner basis consisting of binomials of degree two is readily available for performing a Markov chain. We illustrate our setting with the National Center Test for university entrance examinations in Japan. We also apply our method to testing independence hypotheses involving genotypes at more than one locus or haplotypes of alleles on the same chromosome. 相似文献
48.
, they differ from the Legendre-Clebsch condition. They give information about the Hesse matrix of the integrand at not only
inactive points but also active points. On the other hand, since the inequality state constraints can be regarded as an infinite
number of inequality constraints, they sometimes form an envelope. According to a general theory [9], one has to take the
envelope into consideration when one consider second-order necessary optimality conditions for an abstract optimization problem
with a generalized inequality constraint. However, we show that we do not need to take it into account when we consider Legendre-type
conditions. Finally, we show that any inequality state constraint forms envelopes except two trivial cases. We prove it by
presenting an envelope in a visible form.
Received April 18, 1995 / Revised version received January 5, 1998 Published online August 18, 1998 相似文献
49.
The PdCl(2)-catalyzed cyclization of amino allylic alcohol 16 gave the cyclized product 17a with excellent diastereoselectivity. The versatility of compound 17a as the building block for synthesizing cis-2,6-disubstituted piperidine alkaloids has been demonstrated by a total synthesis of (-)-cassine (1). [reaction--see text] 相似文献
50.
A convergent synthesis of (4R,15R,16R,21S)-rollicosin (1) and (4R,15S,16S,21S)-rollicosin (2) was accomplished. Hydroxy lactone 6a and/or 6b were synthesized from 4-pentyn-1-ol, and α,β-unsaturated lactone 7 was synthesized from γ-lactone 8 and 5-hexen-1-ol. Inhibitory activity of these compounds was examined with bovine heart mitochondrial complex I. 相似文献