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1.
Yongfeng Wang Dr. Jörg Kröger Dr. Richard Berndt Prof. Dr. Werner Hofer Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(7):1261-1265
Heads or tails? The evolution of structural and electronic properties of tin–phthalocyanine films has been analyzed for sub‐monolayer to multilayer coverage using low‐temperature scanning tunneling microscopy. Two molecular conformations are observed: randomly dispersed for the first layer, and islands with a single conformation in subsequent layers.
2.
Dorothea Richter Dipl.‐Chem. Herbert Mayr Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(11):1958-1961
How are dihydropyridines like indoles? Both groups of compounds have similar nucleophilicity parameters N and are therefore suitable substrates for iminium‐catalyzed reactions of α,β‐unsaturated aldehydes. The N parameters of 1,4‐dihydropyridines were derived from the rates of hydride transfer reactions to benzhydrylium ions (see scheme).
3.
Playing the sax : The enantioselective total syntheses of (?)‐ and (+)‐decarbamoyloxysaxitoxin (doSTX) and (+)‐saxitoxin (STX) are reported. A new methodology was developed for the synthesis of STXs, featuring discriminative reduction of the nitro group and N? O bond in nitroisoxazolidine.
4.
Hayato Ishikawa Dr. Takaki Suzuki Yujiro Hayashi Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(7):1304-1307
Taking shortcuts : A remarkably short and high‐yielding asymmetric total synthesis of (?)‐oseltamivir takes advantage of organocatalysis and single‐pot domino operations. The target, known as the drug Tamiflu, is prepared efficiently in a short time, and also its derivatives can be synthesized effectively.
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Natsumi Tanaka Takahiro Suzuki Dr. Takehiko Matsumura Yosuke Hosoya Masahisa Nakada Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(14):2580-2583
Intelligent design : The total synthesis of the cytotoxic (?)‐FR182877 relies on 1) tandem Diels–Alder reactions to close rings A–D (see scheme), 2) a palladium‐mediated 7‐exo‐trig reaction, and 3) an iridium‐mediated isomerization followed by epimerization and stereoselective reduction.
6.
Yu Lu In Su Kim Abbas Hassan David J. Del Valle Michael J. Krische Prof. 《Angewandte Chemie (International ed. in English)》2009,48(27):5018-5021
Unstable? We're able! 1,n‐Glycols serve as synthetic equivalents to unstable dialdehydes in two‐directional carbonyl allylation from the alcohol oxidation level under iridium‐catalyzed transfer hydrogenation conditions. Iterative asymmetric allylation employing 1,3‐propanediol enables the rapid assembly of protected 1,3‐polyol substructures with exceptional levels of stereocontrol.
7.
Lin Li Yu‐Peng Tian Jia‐Xiang Yang Ping‐Ping Sun Jie‐Ying Wu Hong‐Ping Zhou Sheng‐Yi Zhang Bao‐Kang Jin Xiao‐Juan Xing Chuan‐Kui Wang Ming Li Guang‐Hua Cheng Huo‐Hong Tang Wen‐Hao Huang Xu‐Tang Tao Min‐Hua Jiang 《化学:亚洲杂志》2009,4(5):668-680
Mark us bent! The synthesis, structure, and single‐ and two‐photon spectroscopic properties of a series of pyrimidine‐based (bent‐shaped) molecules are reported. These allow structure‐property relationships and guidelines for both the development and application of TPA compounds to be derived.
8.
Yoshihiro Matano Prof. Dr. Makoto Nakashima Hiroshi Imahori Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(22):4002-4005
Mind the (narrow) gap : α‐Ethynylphospholes generated in situ from the corresponding silyl‐capped precursors were converted into a series of α‐(arylethynyl) phospholes bearing functional substituents as well as an α,α′‐linked terphosphole (see scheme). The terphosphole has a narrow HOMO–LUMO gap owing to efficient π conjugation over the three phosphole rings.
9.
Sylvia Kirchberg Roland Fröhlich Dr. Armido Studer Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(23):4235-4238
Indoles are not indolent : Various indoles react with arylboronic acids chemodivergently. C? H arylation of free indole and N‐methylindole gives the corresponding C(2)‐arylated indoles A whereas N‐acylated, N‐benzoylated, and N‐Boc‐protected indoles provide the corresponding arylcarboaminoxylated products B with excellent diastereoselectivity in good to excellent yields.
10.
Daisuke Yamashita Yoshihisa Murata Dr. Naotsuka Hikage Dr. Ken‐ichi Takao Prof. Dr. Atsuo Nakazaki Dr. Susumu Kobayashi Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(8):1404-1406
No bones about it : (?)‐Norzoanthamine, a promising candidate for an anti‐osteoporotic drug, was the target of a total synthesis (see scheme). The final bisaminal formation with AcOH/H2O gave the DEFG ring, while the cyclization precursor was prepared by installing the remaining bisaminal unit after oxidative cleavage of the cyclopentanol moiety.
11.
Paul M. Wehn Dr. J. Du Bois Prof. 《Angewandte Chemie (International ed. in English)》2009,48(21):3802-3805
Weaving an intricate web : A stereoselective synthesis of (?)‐agelastatin A has been developed, which requires 11 steps from commercially available starting material. The application of a Rh‐catalyzed intramolecular olefin aziridination reaction and the subsequent manipulation of the resulting tricyclic intermediate (see scheme) punctuate this study.
12.
Richard S. Grainger Dr. Bhaven Patel Benson M. Kariuki Dr. 《Angewandte Chemie (International ed. in English)》2009,48(26):4832-4835
Bulking up: The thermal barrier to rearrangement of a vic‐disulfoxide is significantly increased through steric buttressing about the (O)S? S(O) bond. Whereas the title compounds represent the most thermally stable vic‐disulfoxides known to date, they also undergo a novel photomediated epimerization at room temperature (see scheme).
13.
Yann Gloaguen Gilles Alcaraz Dr. Anne‐Frédérique Pécharman Eric Clot Dr. Laure Vendier Dr. Sylviane Sabo‐Etienne Dr. 《Angewandte Chemie (International ed. in English)》2009,48(16):2964-2968
A question of coordination mode : Two new borane compounds are prepared. They act as bifunctional ligands as illustrated by their reaction with ruthenium polyhydrides which leads to the formation of two complexes (see scheme) displaying either a δ‐agostic interaction of a η2‐B? H bond involving a trivalent boron atom or a dihydroborate ligation.
14.
Guozhu Zhang Yu Peng Dr. Li Cui Dr. Liming Zhang Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(17):3112-3115
Oxidizing gold? A gold(I)/gold(III) catalytic cycle is essential for the first oxidative cross‐coupling reaction in gold catalysis. By using Selectfluor for gold(I) oxidation, this chemistry reveals the synthetic potential of incorporating gold(I)/gold(III) catalytic cycles into contemporary gold chemistry and promises a new area of gold research by merging powerful gold catalysis and oxidative metal‐catalyzed cross‐coupling reactions.
15.
StephenP. Thomas VarinderK. Aggarwal 《Angewandte Chemie (International ed. in English)》2009,48(11):1896-1898
A breakthrough in the asymmetric hydroboration of notoriously difficult 1,1‐disubstituted alkenes using a new family of highly effective hydroboration reagents is described (see scheme). The intermediate boranes can be oxidized to alcohols or used in Suzuki–Miyaura cross‐coupling reactions.
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17.
Loïc Salmon Guillaume Bouvignies Dr. Phineus Markwick Dr. Nils Lakomek Dr. Scott Showalter Dr. Da‐Wei Li Dr. Korvin Walter Christian Griesinger Prof. Rafael Brüschweiler Prof. Martin Blackledge Dr. 《Angewandte Chemie (International ed. in English)》2009,48(23):4154-4157
A robust procedure for the determination of protein‐backbone motions on time scales of pico‐ to milliseconds directly from residual dipolar couplings has been developed that requires no additional scaling relative to external references. The results for ubiquitin (blue in graph: experimental N? HN order parameters) correspond closely to the amplitude, nature, and distribution of motion found in a 400 ns molecular‐dynamics trajectory of ubiquitin (red).
18.
Hai Zhou Yun‐He Xu Wan‐Jun Chung Teck‐Peng Loh Prof. 《Angewandte Chemie (International ed. in English)》2009,48(29):5355-5357
It does get in! A fluoride‐assisted direct cross‐coupling of cyclic enamides with trialkoxy aryl silanes by a palladium‐catalyzed C? H activation leads to a wide range of enamides in yields of up to 95 %.
19.
Zhixin Tian Steven R. Kass Prof. 《Angewandte Chemie (International ed. in English)》2009,48(7):1321-1323
Preferred protonation : Does electrospray ionization mass spectrometry produce gas‐phase or liquid‐phase structures? The preferred protonation site in p‐aminobenzoic acid depends upon the medium, and the structure of its conjugate acid varies with the solvent used during spraying.
20.
Haye Min Ko Chung Whan Lee Hyung Kyoo Kwon Hea Seung Chung Soo Young Choi Young Keun Chung Prof. Dr. Eun Lee Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(13):2364-2366
Macrolide magic : An enyne cross‐metathesis reaction of an alkynyl boronate with an alkene derivative as well as a radical cyclization reaction of a homopropargylic β‐alkoxyacrylate are the key transformations in the total synthesis of the cytotoxic macrolide (?)‐amphidinolide K.