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排序方式: 共有85条查询结果,搜索用时 15 毫秒
31.
WANG Bao-lei WU Jing HE Feng-qi LI Yong-hong LI Zheng-ming 《高等学校化学研究》2008,24(4):477-480
Thirteen new ethyl 2-(N-substituted-arylsulfonamido)-2-oxoacetates(3a-3m), based on the structure of Ketol-acid reductoisomerase(KARI) inhibitor IpOHA, were designed and synthesized. Their structures were established on the basis of ^1H NMR, IR, MS, and elemental analyses. The bioassay result reveals that the structural changes from hydroxyl group on the N atom of IpOHA to arylsulfonyl groups does not enhance the inhibitory activity of the compounds to KARI in vitro. Compounds 3c, 3h, 3k, and 3m are more effective than IpOHA against the monocotyledonous bamygrass at 100 ug/mL in herbicidal tests. 相似文献
32.
WANG Bao-lei LI Zheng-ming LI Yong-hong WANG Su-hua 《高等学校化学研究》2007,23(3):280-283
Nine ethyl N-hydroxy-N-(substituted)phenyloxamates(2a—2i), based on the structure of the KARI inhibitor IpOHA, were synthesized. Their structures were established on the bases of 1H NMR, IR, ESI-MS and elemental analyses. Among the nine compounds, four show in vitro inhibitory activity on rice KARI, with 2c and 2g[Ki values of (35.2±4.9) and (49.4±6.3) μmol/L] having similar activity to the precursor of IpOHA(A, Ki=34.1±6.7 μmol/L). The results will be helpful to further molecular design of more potent KARI inhibitors. 相似文献
33.
CAO Gang WANG Mei-yi? WANG Ming-zhong WANG Su-hua LI Yong-hong LI Zheng-ming . State Key Laboratory of Elemento-Organic Chemistry Research Institute of Elemento-Organic Chemistry Nankai University Tianjin P. R. China . College of Chemistry Chemical Engineering North University for Ethnics Yinchuan 《高等学校化学研究》2011,27(1):60-65
Sulfonylurea herbicides have been applied worldwide in agriculture. Some sulfonylurea residues might exist in soil longer than that people expected. However, flupyrsulfuron-methyl-sodium which was firstly reported as a new 5-substituted sulfonylurea herbicide has less than one month residual life. Therefore, 5-substituted benzenesulfonylureas are potential molecules to regulate its residual situation. In order to develop new sulfonylurea derivatives, the substituent on the critical 5-posotion of the benzene... 相似文献
34.
Syntheses of 1,3,4-Thia(oxa)diazole-substituted Pyrazole Derivatives and Their Fungicidal Activities
WANGWen-yan ZHAOWei-guang LIZheng-ming 《高等学校化学研究》2004,20(5):543-547
A series of 1,3,4-oxadiazole or 1.3.4-thiadiazole-substituted pyrazole derivatives were synthesized from 4-pyrazole formhydrazide; their biological activities were studied. The structures of all the new compounds were confirmed by means of spectroscopic methods and microanalyses. The preliminary bioassay results indicate that some compounds of them have a good fungicidal activity against Phoma asparagi and Physalospora piricola Nose. 相似文献
35.
LIAOLian-an FANGHong-yun LIZheng-ming FANZhi-jin 《高等学校化学研究》2004,20(5):551-557
Fourteen new derivatives of avermectin B1a, and ivermectin B1a were synthesized from C5-O-triphenyl silylavermectin B1a and ivermectin B1a (yield from 40% to 83%). Their chemical structures were characterized by means of IR. ^1H NMR, ^13C NMR and FAB-MS spectrometries. Some of them show excellent insecticidal activity. 相似文献
36.
L-shell ionization cross sections of Nb by electron impact in the energy range from 3 to 40 keV have been determined with a Si(Li) X-ray detector. Influence of reflected electrons from backing on the measurement was corrected using an electron transport model. The experimental results are compared with theoretical calculations of Gryzinski and McGuire. 相似文献
37.
用一系列含碳量(wC)在0.002%~0.03%范围内的标准物质在直读光谱仪上按选定的工作条件测定各样品的碳量。根据所得每一样品的一系列测定值以及各项统计量,分析并判断了直读光谱法在测定钢板中超低碳含量的准确度和精密度水平。试验结果表明:1测定结果的准确度受样品的基体背景及仪器标准化条件的影响,引入了系统误差;据此建议选择与待测样品基体匹配的标准物质校准仪器并选择合理的仪器标准化条件。2在上述含碳量范围内,所得测定值的S%值(包括10次测定和5次测定的计算值)差异较小,其极值之差为3×10-4%,但对相对标准偏差有显著影响,其最低值在2%左右,而最高值达21%。3在所选定的测定条件下,对碳含量在10-5数量级的样品而言,准确度或系统误差的波动范围在±1×10-4%范围内。 相似文献
38.
Yu Zhao Li-xia Xiong Li-ping Xu Hongxue Wang Han Xu Hua-bin Li Jun Tong Zheng-ming Li 《Research on Chemical Intermediates》2013,39(7):3071-3088
In search of environmentally benign insecticides with high activity, low toxicity and low residue, a series of novel anthranilic diamides containing allyl ether were designed and synthesized. All the compounds were characterized by 1H NMR spectroscopy, HRMS or elemental analysis. The single crystal structure of 18e was determined by X-ray diffraction. The insecticidal activities of the new compounds were evaluated. The results showed that some compounds exhibited excellent insecticidal activities against Lepidoptera pests. Among this series compounds, 18l showed 100 % larvicidal activity against Mythimna separate Walker and Plutella xylostella Linnaeus at the test concentration. 相似文献
39.
Yang LB Li L Huang SX Pu JX Zhao Y Ma YB Chen JJ Leng CH Tao ZM Sun HD 《Chemical & pharmaceutical bulletin》2011,59(9):1102-1105
Four new diterpenoides, isolophanthins A-D (1-4) together with seven known abietane diterpenoides (5-11), have been isolated from Isodon lophanthoides var. gerardianus. The new diterpenoides were elucidated by spectroscopic analysis. Some of them showed significant activities against HBsAg and HBeAg of hepatitis B virus in Hep G 2.2.15 cells, as well as the human tumor cell lines, HL-60, A-549, MOLT-4, and BEL-7402. 相似文献
40.