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151.
Alois Zinke 《Monatshefte für Chemie / Chemical Monthly》1932,61(1):1-14
Ohne Zusammenfassung 相似文献
152.
Alois Smolka 《Monatshefte für Chemie / Chemical Monthly》1887,8(1):379-390
Ohne Zusammenfassung 相似文献
153.
154.
Ohne ZusammenfassungAm Schlusse meiner Ausführung angelangt, bitte ich noch meinen verehrten Lehrer Hofrat Adolf Lieben, meinen ergebensten Dank entgegenzunehmen für die freundliche Unterstützung, die er meiner Arbeit durch seine Ratschläge angedeihen ließ, und für das Interesse, das er ihr entgegenbrachte.Auch danke ich hier dem Herrn Privatdozenten Dr. C. Pomeranz für seine freundliche Unterstützung. 相似文献
155.
Dipl.‐Chem. Jens Willwacher Prof. Alois Fürstner 《Angewandte Chemie (International ed. in English)》2014,53(16):4217-4221
A concise synthesis of the putative structure assigned to the highly cytotoxic marine macrolide mandelalide A ( 1 ) is disclosed. Specifically, an iridium‐catalyzed two‐directional Krische allylation and a cobalt‐catalyzed carbonylative epoxide opening served as convenient entry points for the preparation of the major building blocks. The final stages feature the first implementation of terminal‐acetylene metathesis into natural product synthesis, which is remarkable as this class of substrates was beyond reach until very recently; key to success was the use of the highly selective molybdenum alkylidyne complex 42 as the catalyst. Although the constitution and stereochemistry of the synthetic samples are unambiguous, the spectra of 1 as well as of 11‐epi‐ 1 deviate from those of the natural product, which implies a subtle but deep‐seated error in the original structure assignment. 相似文献
156.
Saskia Schulthoff James Y. Hamilton Marc Heinrich Yonghoon Kwon Conny Wirtz Alois Fürstner 《Angewandte Chemie (International ed. in English)》2021,60(1):446-454
Total synthesis allowed the constitution of the cytotoxic marine macrolides of the formosalide family to be confirmed and their previously unknown stereostructure to be assigned with confidence. The underlying blueprint was inherently modular to ensure that each conceivable isomer could be reached. This flexibility derived from the use of strictly catalyst controlled transformations to set the stereocenters, except for the anomeric position, which is under thermodynamic control; as an extra safety measure, all stereogenic centers were set prior to ring closure to preclude any interference of the conformation adopted by the macrolactone rings of the different diastereomers. Late‐stage macrocyclization by ring‐closing alkyne metathesis was followed by a platinum‐catalyzed transannular 6‐exo‐dig hydroalkoxylation/ketalization to craft the polycyclic frame. The side chain featuring a very labile unsaturation pattern was finally attached to the core by Stille coupling. 相似文献
157.
The 18-electron half-sandwich iron(0) complex [CpFe(C2H4)2] [Li(tmeda)] (1a), which is readily available in multigram quantities from inexpensive starting materials (ferrocene, ethylene, Li sand), is shown to be an efficient catalyst for the Alder-ene reaction of various 1,6(7)-enynes. Thereby, the presence of the labile alkene ligands in the ferrate catalyst is essential since the analogous complex [CpFe(CO)2]Na is catalytically incompetent. The cycloisomerizations catalyzed by 1a are compatible with various functional groups and turned out to be highly diastereoselective with regard to the configuration of the newly formed alkenes as well as relative stereochemistry at the ring junction. The alkyne moiety in the substrates may be terminal, silylated, or substituted with various groups, including cyclopropane rings. Likewise, the alkene substructure can be varied to a large extent, with cycloalkenes of ring sizes >/=7 being particularly suitable. 相似文献
158.
A largely catalysis based approach to optically active haouamine A (-)-1 is presented, which provides the hexacyclic compound previously used to construct this cytotoxic marine alkaloid. 相似文献
159.
Oxygenated Metabolites of n‐3 Polyunsaturated Fatty Acids as Potential Oxidative Stress Biomarkers: Total Synthesis of 8‐F3t‐IsoP, 10‐F4t‐NeuroP and [D4]‐10‐F4t‐NeuroP 下载免费PDF全文
Dr. Alexandre Guy Dr. Camille Oger Dr. Johannes Heppekausen Dr. Cinzia Signorini Claudio De Felice Prof. Alois Fürstner Dr. Thierry Durand Dr. Jean‐Marie Galano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(21):6374-6380
A wide variety of metabolic products of polyunsaturated fatty acids is of paramount importance for improving our medical knowledge in the field of oxidized lipids. Two novel metabolites of n‐3 polyunsaturated fatty acids, 8‐F3t‐IsoP and 10‐F4t‐NeuroP as well as a deuterated derivative thereof were synthesized based on an acetylenic intermediate. An original approach achieved lateral chain insertion of 8‐F3t‐IsoP by a ring‐closing alkyne metathesis/semi‐reduction strategy together with a temporary tether. 相似文献
160.
Total Synthesis of Mycinamicin IV as Integral Part of a Collective Approach to Macrolide Antibiotics
Georg Späth Prof. Alois Fürstner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(11):e202104400
The total synthesis of the 16-membered macrolide mycinamicin IV is outlined, which complements our previously disclosed, largely catalysis-based route to the aglycone. This work must also be seen in the context of our recent conquest of aldgamycin N, a related antibiotic featuring a similar core but a distinctly different functionalization pattern. Taken together, these projects prove that the underlying blueprint is integrative and hence qualifies for a collective approach to this prominent class of natural products. In both cases, the final glycosylation phase mandated close attention and was accomplished only after robust de novo syntheses of the (di)deoxy sugars of the desosamine, chalcose, mycinose and aldgarose types had been established. Systematic screening of the glycosidation promoter was also critically important for success. 相似文献