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981.
<正>A series of 2-amino-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidinyl substituted diaryl urea derivatives was designed and synthesized.Their in vitro cytotoxicities against two cancer cell lines(Bel-7402 and A549) were evaluated by standard MTT assay.Six of tested compounds 6,8,10,17,21 and 22 exhibited more potent cytotoxicity superior to sorafenib.The structure activity relationship(SAR) study indicates that 2-amino-5,6,7,8-tetrahydropyrido- [4,3-d]pyrimidinyl group was an option for cytotoxic potency. 相似文献
982.
MAO Mao GU Cheng-zhi YIN Hao SONG Qin-hua LI Qlan-rong 《高等学校化学研究》2010,26(2):198-203
With the aid of a Pyrolysis-GC/TOF MS technique,the pyrolysis behaviour of two menthyl esters of N-benzoxycarbonyl amino acid was investigated.A clear pattern emerges involving the cleavage of the bond linking the menthyl ring to the carboxy group,followed by further degradation of the fragments.The major pyroproducts were p-menth-1-ene pyrolysed at a higher temperature or p-menth-2-ene pyrolysed at a lower temperature,and va-rious derivatives of cyclohexene pyrolyzed from the menthyl ring.In addition,some ... 相似文献
983.
对壳聚糖氨基和羟基进行化学改性,合成了水溶性双功能化壳聚糖衍生物O-季铵化-N-壳聚糖Schiff碱(O-HTCCS);用红外光谱表征了产物的结构;确定了O-HTCCS的最佳合成条件,并测定了其溶解性能.结果表明,合成O-HTCCS的最佳条件为:壳聚糖Schiff碱/缩水甘油三甲基氯化铵(GTMAc)摩尔比为1∶5;反应时间24 h;反应温度70℃.在最佳条件下合成O-HTCCS的产率为78.5%,季铵化度为89.7%.与此同时,O-HTCCS的水溶性随季铵化度的增大而提高,季铵化度达到70%以上能溶于水;且其在有机溶剂中的溶解性优于壳聚糖. 相似文献
984.
Luo Mei Sun Jie Zhou Shi-Ming Yin Hao Hu Ke-Liang 《Research on Chemical Intermediates》2010,36(9):1049-1054
Two opposite configuration (R/S) of chiral complexes (C8H11N)2·CuCl2 were obtained from the reaction of chiral d(+)/l(−)-α-ethylphenyl amine with copper chloride (II) in dry ethanol. The crystal structures of 1a and 1b were characterized by
IR, elemental analysis and X-ray crystallography. 相似文献
985.
Shoushuang Huang Jianmei Huang Jian Yang Prof. Jun‐Jun Peng Qingbo Zhang Dr. Feng Peng Prof. Hongjuan Wang Dr. Hao Yu Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(20):5920-5926
Heterodimer nanostructures have attracted extensive attention, owing to an increasing degree of complexity, functionality, and then importance. So far, all the reported ones are built from solid nanoparticles. Herein, nearly monodisperse heterodimer nanostructures are constructed by hollow PbSx and solid Au domains simultaneously through a mild reaction between PbS nanocrystals and the gold species in the presence of dodecylamine. Control experiments clearly reveal the underlying formation mechanism of the hollow PbSx–solid Au heterodimers. The AuIII species in the solution, lead to the etching of PbS nanocrystals and the AuI species facilitate the control of the number of gold domains per nanoparticle. Dodecylamine molecules not only work as a stabilizer in the reaction, but also act as a reducing agent that could greatly affect the morphology of the product. The optical properties of the heterodimers are investigated based on UV/Vis absorption spectroscopy and Raman spectroscopy. This novel heterodimer nanostructure pushes the development of complex nanocrystal‐based architectures forward, and also provides many opportunities for potential applications. 相似文献
986.
Hui Ming Ge Dr. Wen Hao Yang Yan Shen Dr. Nan Jiang Dr. Zhi Kai Guo Qiong Luo Qiang Xu Prof. Jing Ma Prof. Ren Xiang Tan Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(21):6338-6345
Two novel resveratrol aneuploids, hopeachinols A ( 1 ) and B ( 2 ), as well as a potent immunosuppressive polyphenol diptoindonesin G ( 3 ) were characterized from the ethanol extract of Hopea chinensis stem barks. The structure of the polyphenols was accommodated by comprehensive spectroscopic analysis with the absolute stereochemistry determined by the CD approach coupled with theoretical ECD spectra computer‐generated through the Gaussian 03 program. The distinct structure and biological profile of 3 recommended it as a starting molecule for the relevant drug discovery. 相似文献
987.
Yang Yu Hao Gao Yi Dai Ying Wang He‐Ru Chen Xin‐Sheng Yao 《Helvetica chimica acta》2010,93(4):763-771
Eight new monoterpenoids, jasminoside J ( 1 ), jasminoside K ( 2 ), 6′‐O‐trans‐sinapoyljasminoside B ( 3 ), 6′‐O‐trans‐sinapoyljasminoside L ( 4 ), jasminosides M–P ( 5 – 8 ), together with three known analogues, jasminoside C ( 9 ), jasminol E ( 10 ), and sacranoside B ( 11 ), were isolated from the fruit of Gardenia jasminoides Ellis (Rubiaceae). Their structures were elucidated by spectral and chemical methods. 相似文献
988.
Yang Zhang Chang‐Heng Tan Jun‐Jie Tan Pei‐Ming Yang Shan‐Hao Jiang Xiang Ni Da‐Yuan Zhu 《Helvetica chimica acta》2010,93(7):1407-1412
Three new, 1 – 3 , and seven known phenolic and terpenic glycosides were isolated from the BuOH‐soluble fraction of 95% EtOH extract of the roots and rhizomes of Celastrus orbiculatus. The structures of the new compounds were elucidated as carvacrol 2‐O‐α‐L ‐rhamnopyranosyl‐(1→6)‐β‐D ‐glucopyranoside ( 1 ), 5‐methoxycarvacrol 2‐O‐α‐L ‐rhamnopyranosyl‐(1→6)‐β‐D ‐glucopyranoside ( 2 ), and 15‐hydroxytorreyol 10‐O‐β‐D ‐apiofuranosyl‐(1→6)‐β‐D ‐glucopyranoside ( 3 ) on the basis of spectroscopic analysis and chemical methods. 相似文献
989.
Three novel sandwich‐type polyoxotungstates ( 1 – 3 ) were synthesized in good yield using an in‐situ conventional solution synthesis method by reaction in aqueous media below 80 °C. Compounds 1 – 3 represent the first structurally characterized β‐B‐BiW9 sandwich‐type polyoxometalates with triethanolamine cations. All three compounds have the same building unit [(X(H2O)3)2(X0.5W0.5O)2(β‐B‐BiW9O33)2)]10– [X = MnII ( 1 ), CoII ( 2 ), NiII ( 3 )]. The adjacent units of 1 or 2 are joined by Na+ cations in different ways to construct 1D chains or 2D sheets. A 3D supramolecular structure is further formed by hydrogen bond interactions among water molecules and protonated triethanolamine cations. Meanwhile only compound 3 shows a 0D structure. The compounds were characterized by elemental analysis, IR spectroscopy, TG analysis, and single‐crystal X‐ray diffraction. Magnetic measurements on a sample of 1 show the presence of paramagnetic interactions. 相似文献
990.