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111.
Masataka Chida Hidenori Katsurada Kohji Matsumoto 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》2014,84(1):31-47
We prove a formula of Petersson’s type for Fourier coefficients of Siegel cusp forms of degree 2 with respect to congruence subgroups, and as a corollary, show upper bound estimates of individual Fourier coefficients. The method in this paper is essentially a generalization of Kitaoka’s previous work which studied the full modular case, but some modification is necessary to obtain estimates which are sharp with respect to the level aspect. 相似文献
112.
Dr. Jun Nakamura Hidenori Yamashiro Hiroto Miya Dr. Kenzo Nishiguchi Dr. Hideki Maki Prof. Dr. Hirokazu Arimoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(36):12104-12112
Vancomycin‐resistant Staphylococcus aureus (S. aureus) (VRSA) uses depsipeptide‐containing modified cell‐wall precursors for the biosynthesis of peptidoglycan. Transglycosylase is responsible for the polymerization of the peptidoglycan, and the penicillin‐binding protein 2 (PBP2) plays a major role in the polymerization among several transglycosylases of wild‐type S. aureus. However, it is unclear whether VRSA processes the depsipeptide‐containing peptidoglycan precursor by using PBP2. Here, we describe the total synthesis of depsi‐lipid I, a cell‐wall precursor of VRSA. By using this chemistry, we prepared a depsi‐lipid II analogue as substrate for a cell‐free transglycosylation system. The reconstituted system revealed that the PBP2 of S. aureus is able to process a depsi‐lipid II intermediate as efficiently as its normal substrate. Moreover, the system was successfully used to demonstrate the difference in the mode of action of the two antibiotics moenomycin and vancomycin. 相似文献
113.
Hiromu Kashida Hidenori Azuma Ryoko Maruyama Yasuyuki Araki Takehiko Wada Hiroyuki Asanuma 《Angewandte Chemie (International ed. in English)》2020,59(28):11360-11363
Herein we report the construction of efficient light‐harvesting antennae by hybridization of DNA oligonucleotides containing high densities of fluorophores into DNA junctions through d ‐threoninol. Six pyrene donors could be incorporated into each arm without self‐quenching. A perylene acceptor was located at the center of the junction. Antenna effects of a duplex and three‐ to eight‐way junctions were systematically compared. Six‐ and eight‐way junctions had the highest antenna effects, and their effective absorption coefficients were 8.5 times higher than that of perylene. Interestingly, even‐numbered junctions had higher efficiencies than odd‐numbered junctions. Nondenaturing gel analyses and fluorescence lifetime measurements demonstrated that the strong odd–even effects were derived from differences in the stability of junctions. The results presented will guide the design of efficient artificial photosynthetic systems. 相似文献
114.
Nitroalkanes have recently been demonstrated to be useful synthetic intermediates for a variety of trans- formations. They have, for example, been converted to carbonyl, la) nitrile oxide,lb) and amino compounds.1c) Especially, 2-aryl-1-nitroalkanes are important in connection with the synthesis of biochemically and pharmacologically interesting compounds. 2) They have also been used as synthetically equivalent to enamines and enolates.3) A widely employed method4) for the synthesis of nitroalkanes involves NaBH4 reduction of conjugated nitroalkenes. The NaBH4 reduction of nitro- alkenes derived from aliphatic aldehydes4b) or ketones5) usually proceeds smoothly in good yields. However, the reduction of 2-aryl-1-nitroalkenes with NaBH4 produces low yields of products due to undesired side reactions such as dimerization.4) 相似文献
115.
Microcarpalide is a strong microfilament disrupting agent. The convergent and stereoselective synthesis of microcarpalide was succeeded via Julia olefination and macrolactonization. 相似文献
116.
117.
Treatment of alkyl halides, including tertiary alkyl bromides, with benzylic or allylic Grignard reagent in the presence of a catalytic amount of silver nitrate in ether yielded the corresponding cross-coupling products in high yields. The coupling reactions of tertiary alkyl halides provide efficient access to quaternary carbon centers. 相似文献
118.
Nagase H Yamamoto N Nemoto T Yoza K Kamiya K Hirono S Momen S Izumimoto N Hasebe K Mochizuki H Fujii H 《The Journal of organic chemistry》2008,73(20):8093-8096
The treatment of morphinan 1 with NaH and MsCl provided very stable iminium salt 7 possessing propellane skeleton. One of the synthesized iminium salts 7, isobutyl derivative 7b, was crystallized and its structure was determined by X-ray crystallography. The natural bond orbital analysis suggested that the stability of the iminium should result from the stereoelectronic effect (hyperconjugation) attributed to their own structures. 相似文献
119.
Stable immobilization of an oligonucleotide probe on a gold substrate using tripodal thiol derivatives 总被引:1,自引:0,他引:1
Sakata T Maruyama S Ueda A Otsuka H Miyahara Y 《Langmuir : the ACS journal of surfaces and colloids》2007,23(5):2269-2272
We proposed an interface molecule for immobilization of DNA probes on solid substrates of DNA chips. We have designed and synthesized tripodal thiol derivatives for stable immobilization of oligonucleotide probes on a gold surface. On the basis of the tetrahedral structure of tripod, the tripodal thiol derivatives were bonded upright to the gold substrate, which would control the orientation of oligonucleotide probes. When the gold substrate with oligonucleotide probes tethered using the thiol derivatives was exposed to deionized water at higher temperatures, the tripodal interface molecules were attached to the gold surface more stably than the single contact molecules. The DNA chip platform combined with the functional interface molecule is suitable for a reproducible, inexpensive, and high-throughput detection system for genetic analyses in clinical diagnostics. 相似文献
120.
Hydrogen-bonding triarylamines, 4-(N,N-bis(4-methoxyphenyl)amino)benzoic acid (TPA1), 5-(N,N-bis(4-methoxyphenyl)amino)isophthalic acid (TPA2), and N-(4-(1H-benzimidazol-2-yl)phenyl)-N,N-bis(4-methoxyphenyl)amine (BImTPA), were synthesized as radical cation precursors. TPA1 and TPA2 are readily p-doped by AgSbF(6) to give highly persistent radical cations. Poor solid-state spin yields of the radical cation from BImTPA may be due to spin delocalization. 相似文献