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51.
电子传输材料1,3,4-恶二唑衍生物和1,2,4-三唑衍生物的DFT研究 总被引:1,自引:0,他引:1
采用密度泛函理论B3LYP方法,对1,3,4噁二唑衍生物和1,2,4三唑衍生物两类电子传输材料在中性、阴离子态和阳离子态下分别进行几何结构优化计算.结果表明,1,3,4噁二唑衍生物的电子传输过程主要是分子内噁二唑上的N→O电子转移,1,2,4三唑衍生物的电子传输过程主要是分子内三唑上N(双键)→N(单键)以及三唑环向与N相连的苯环电子转移.当其苯环上3位被拉电子基团取代后,其电子传输性能提高;而被给电子基团取代后,电子传输性能降低. 相似文献
52.
L. V. Batog V. Yu. Rozhkov E. V. Shatunova M. I. Struchkova 《Russian Chemical Bulletin》2008,57(1):165-169
Methods for the synthesis of 4-amino-4′-R-3,3′-(NNO)-azoxy-1,2,5-oxadiazoles (amino-azoxyfurazans) with 4-nitro-1,2,3-triazol-1-yl
and 1,2,3-triazolo[4,5-c]furazan-5-yl substituents (R) by cycloaddition of morpholinonitroethylene to 4′-amino-4-azido-3,3′-(ONN)-azoxyfurazan or
oxidative condensation of 3-R-4-aminofurazans with 4-trifluoroacetylamino-3-nitrosofurazan were elaborated. Related polycyclic
azo derivatives were also synthesized.
For preliminary communication, see Ref. 1.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 159–163, January, 2008. 相似文献
53.
《Arabian Journal of Chemistry》2023,16(4):104610
In present work, a series of novel structural hybrids of 1,3,4-oxadiazole and carbamothioate was designed by chemical modification of 2-(4-isobutylphenyl)propanoic acid. Target compounds (7a-f) were synthesized in significant yields (84–88 %) by coupling compound (4) with different electrophiles under different reaction conditions. The structures of oxadiazole based carbamothionate derivatives were confirmed by spectroscopic (FTIR, 1H NMR, 13C NMR) and physiochemical methods. During in-vivo experimentation, all synthesized compounds were tested through 6 Hz (32 mA) and PTZ (80 mg/kg) mouse seizure models. The 7b and 7c showed significant outcomes (P < 0.05) in terms of seizure severity, protection and mortality. The behavioural outcomes of PTZ tests were further strengthened with video-electroencephalogram (vEEG) findings in which EEGs were analyzed for epileptic spikes to understand the impact of 7b and 7c treatment on these ictal activities. The 7b was found most efficient in reducing the seizure spiking activity in brains of PTZ-treated mice while both 7b and 7c significantly reduced overall PTZ-induced seizure severity. The molecular docking studies also predicted the BBB permeability, reduced binding energies and good compound interaction with GABAA receptors and SV2A protein. Therefore, the observed pharmacological outcomes might be attributed to the GABAA agonistic and SV2A modulating potential of these oxadiazole-carbamothioate hybrid compounds. 相似文献
54.
A series of condensation products of 1-(9-butylcarbazol-3-yl)-5-oxopyrrolidine-3-carbohydrazide with 2-propanone, 2-butanone,
2,4-pentanedione, 2,5-hexanedione, ethyl 3-oxobutanoate, and aromatic aldehydes was obtained. Substituted oxadiazoles were
synthesized from carbohydrazide or the corresponding hydrazone. Spectral properties of the synthesized compounds were examined.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1009–1017, July, 2008. 相似文献
55.
Liangrun Dong Baojing Song Jian Wu Zengxue Wu Yunying Zhu Xuewen Chen 《Phosphorus, sulfur, and silicon and the related elements》2016,191(6):904-907
A series of novel thioether derivatives containing 1,3,4-oxadiazole/thiadiazole and emodin moieties were designed and synthesized. The structures of the target compounds were confirmed by 1H NMR, 13C NMR, Infrared, and elemental analysis. The results of bioactivity analysis showed that most of the target compounds exhibited moderate to good antiviral activity against tobacco mosaic virus at a concentration of 500 mg/L. Especially, among the title compounds, Y2, Y8, and Y10 possessed appreciable curative activity in vivo, with inhibition rates of 50.51, 52.08, and 54.62%, respectively, which were similar to that of Ningnanmycin (53.40%). 相似文献
56.
Microwave-assisted 1,3-dipolar cycloaddition of 5-azidomethyl 3-aryl-substituted 1,2,4-oxadiazoles to electron-deficient alkyne; phenyl propiolic acid affords a series of 1,2,3-triazole derivatives carrying 3-p-substitutedphenyl-1,2,4-oxadiazolyl methyl unit. The structures of all the cycloadducts were elucidated by IR, NMR (1H, 13C, 2D), MASS (low and high resolution) spectra, X-ray diffraction data, and physical characteristics (melting points and Rf values). 相似文献
57.
58.
脂肪族二酸二烷基双去氢枞基双噁二唑的合成及除草活性 总被引:1,自引:0,他引:1
以去氢枞酸为原料,制备去氢枞酸酰氯.以脂肪族二酸为原料,经过脂肪族二酸二乙酯得到脂肪族二酸二酰肼.脂肪族二酸二酰肼与去氧枞酸酰氯在相转移催化下反应得到N,N'-二去氢枞酰基取代脂肪族二酸二酰肼,再脱水环合,得到5个标题化合物脂肪族二酸二烷基双去氢枞基双噁二唑.通过元素分析,IR,MS,1H NMR和13C NMR对所合成的新化合物进行了结构表征.初步的除草活性测试表明,化合物6b~6e在100 μg/mL浓度下对油菜的胚根生长具有良好的抑制作用,抑制率均超过80%. 相似文献
59.
在冰醋酸存在下, 4-取代苯乙酮和溴素容易进行溴代反应, 得到α-溴-4-取代苯乙酮; 将其和1,2,4-三唑在丙酮中反应, 得到α-(1,2,4-三唑-1-基)-4-取代苯乙酮2; 在冰醋酸催化下, 2和4-取代苯甲酰肼1进行缩合, 得到相应酰腙衍生物3; 化合物3在乙酸酐的作用下环化生成一系列2-[1-(1,2,4-三唑)甲基]-3-乙酰基-2,5-二取代芳基-1,3,4-噁二唑啉4. 化合物4的结构经IR, 1H NMR, MS, 元素分析和单晶衍射确证. 相似文献
60.
Development of novel, safe and effective drug candidates combating the emerging drug resistance has remained a major focus in the mainstream of anti-tuberculosis research. Here, we inspired to design and synthesize series of new pyridin-4-yl-1,3,4-oxadiazol-2-yl-thio-ethylidene-hydrazinecarbothioamide derivatives as potential anti-tubercular agents. The anti-tubercular bioactive assay demonstrated that the synthesized compounds exhibit potent anti-tubercular activity (MIC = 3.9–7.81 μg/mL) in comparison with reference drugs Rifampicin and Isoniazid.We employed pharmacophore probing approach for the identification of CYP51 as a possible drug target for the synthesized compounds. To understand the preferable binding mode, the synthesized molecules were docked onto the active site of Sterol 14 α-demethylases (CYP51) target. From the binding free energy of the docking results it was revealed that the compounds were effective CYP51 inhibitors and acts as antitubercular agent. 相似文献