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51.
1INTRODUCTIONPolarizedketenedithioacetalshavebeenex-tensivelyusedasbuildingblocksinorganicsyn-thesis,especiallyinthesynthesisofheterocycliccompounds[1~6].Pyrazoleanditsderivativesrepre-sentoneofthemostactiveclassesofcompoundspossessingwidespectraofbiologicalactivities.Overthepastfewyears,considerableevidenceshavebeenaccumulatedtodemonstratetheefficacyofpyrazolederivatives,suchasantibacterial[7],fun-gicidal[8],herbicidal[9],insecticidal[10]andotherbiologicalactivities[11,12].Uptonow,alarg… 相似文献
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Synthesis of pyrimido[1,2-a]benzimidazole and pyrano[2,3-c]pyrazole derivatives were achieved using polyethylene glycol (PEG-400) as promoting reaction medium in water under catalyst-free conditions at reflux and room temperature, respectively. The structure of pyrimido[1,2-a]benzimidazole was confirmed using 1H NMR, 13C NMR, DEPT, and HMBC experiments. The promising points for the present methodology are efficiency, generality, high yield, short reaction time, cleaner reaction profile, ease of product isolation, simplicity, potential of recycling reaction medium, and finally agreement with green chemistry protocols. 相似文献
54.
Instudyonnewpharmaceuticalsandagrochemicals,theapplicationofheterocyclesisaveryimportantmethod,whichcanimprovethebiologicalactivities.Intheseyears.moreandmorenewagrochemicalshavebeensynthesizedwhichhavethestructurescontainingheterocycles.especiallypy... 相似文献
55.
Aurora Molinari Alfonso Oliva Marlene Arismendi Elizabeth Imbarack Cristian Glvez Javier Maldonado Arturo San Feliciano 《Journal of heterocyclic chemistry》2015,52(2):620-622
New fused pyrazolo‐1,4‐naphthoquinones were prepared from the reaction of hydrazines with 6‐(4‐methyl‐3‐pentenyl)‐1,4‐naphthoquinone. The reaction was extended to hydroxylamine to afford the corresponding isoxazolo‐1,4‐napthoquinone compound. 相似文献
56.
Dr. Yongxing Tang Prof. Dr. Haixiang Gao Dr. Damon A. Parrish Prof. Dr. Jean'ne M. Shreeve 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(32):11401-11407
Triazole links and polynitropyrazole rings give rise to compounds with energetic properties. These materials were fully characterized by NMR and infrared spectroscopy, elemental analysis, and differential scanning calorimetry (DSC). In addition, the structures of compounds 5 and 8 were confirmed by single‐crystal X‐ray diffraction analysis. Detonation properties, calculated from heats of formation and experimental densities, thermal stabilities, and impact and friction sensitivities support the potential use of these materials for explosive applications. 相似文献
57.
Chemoselective Route for Synthesis of N‐Aryl‐3‐oxochromeno[2,3‐c]pyrazole‐2(3H)‐carbothioamide Derivatives 下载免费PDF全文
A chemoselective route for the synthesis of chromeno[2,3‐c]pyrazole‐2(3H)‐carbothioamide derivatives by a five‐component reaction of salicylaldehyde, malononitrile, NH2NH2?H2O, aryl isothiocyanate, and H2O in EtOH/AcOH mixture is reported. This new protocol has the advantages of high yields, short reaction times, ease of operation, and simple purification. All structures were confirmed by IR, 1H‐ and 13C‐NMR, and MS analyses. A plausible mechanism for this type of reaction is proposed (Scheme 2). 相似文献
58.
A convenient synthesis of 3-substituted pyrazole derivatives by a mixed anhydride method using i-butylchloroformate and N-methylmorpholine at ?20 °C in tetrahydrofuran and study of in vitro antibacterial activities of the prepared compounds against Staphylococcus epidermidis, Bacillus subtilis, Pseudomonas aeruginosa, and Proteus valguris by agar-diffusion method were carried out. The results suggested that the products 4a, 4b, and 4c exhibited moderate to feeble inhibition against all test bacteria at greater concentration but 4d was best against Staphylococcus epidermidis (22 mm) and worst against Pseudomonas aeruginosa (16 mm) at the greatest concentration (2.5 mg/ml), and the activities decreased with decrease in concentration. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
59.
含吡唑甲酰胺基E-β-法尼烯类似物的设计、合成及生物活性 总被引:2,自引:0,他引:2
为发现防治蚜虫的新型活性化合物,以蚜虫报警信息素E-β法尼烯(EBF)为先导,设计合成了20个未见文献报道的含吡唑环甲酰胺基EBF类似物,所有化合物结构均通过1H NMR,IR及HRMS确证.初步生物活性研究表明,部分目标化合物对五日龄豆蚜(Aphis craccivora Koch)在600mg/L时表现出较好的杀虫活性,其中5a及5k对豆蚜活性与商品化药剂氟虫腈及先导化合物EBF相当,甚至优于EBF.对影响目标化合物的活性因素进行了初步探讨. 相似文献
60.
A new polyoxomolybdate compound [Ag 3 (HL) 4 ](PMo 12 O 40)] 1 (HL=3-(2-pyridyl)pyrazole) has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction,elemental analyses,TG and IR spectroscopy.The compound crystallizes in triclinic,space group P1 with a=10.375(3),b=12.076(3),c=13.196(4),α=84.170(4),β=71.961(3),γ=86.326(4)°,V=1563.1(7)3,C 32 H 28 Ag 3 Mo 12 N 12 O 40 P,M r=2726.52,D c=2.897 g/cm 3,μ(MoKα)=3.366 mm 1,F(000)=1284,Z=1,the final R=0.0587 and wR=0.1312 for 4139 observed reflections (I > 2σ(Ⅰ)).X-ray diffraction analyses reveal that the PMo 12 O 40 3clusters in compound 1 are linked by four Ag 3 (HL) 4 3+ units via the terminal oxygen atoms to form a two-dimensional architecture.The symmetrical unit of Ag 3 (HL) 4 3+ exhibits two distinct Ag(Ⅰ) environments:a two-coordinate {AgN 2 } site and a five-coordinate {AgN 3 O 2 } site which links to two molybdate clusters. 相似文献