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531.
LI Xiao-Honga ZHANG Rui-Zhoub CHENG Xin-Lua YANG Xiang-Donga② a 《结构化学》2006,25(11):1351-1358
1 INTRODUCTION The earliest antibacterial agents used as chemo- therapeutic drugs in the 1920s were synthetic agents, such as sulponamides. Since the discovery of peni- cillin and its entry into clinical use in the 1940s, the field has been dominated over the past 50 years by natural products or their semi-synthetic derivatives. The fluoroquinolones are the only synthetic anti- bacterial agents to rival β-lactams for impact in clinical usage in the antibacterial field. In recent years, … 相似文献
532.
1 INTRODUCTIONSulfoxideisknowntoformcoordinationcompoundswithLanthanide(Ⅲ)andtheirsyntheses,propertiesandvariousphysicalcharacteristicshavebeenreport-ed〔1~9〕.However,therearesomanydifficultyinpreparingthekindoflanthanidecomplexesbecausetheanionsuseda… 相似文献
533.
ZHANG Yu Hua a WU Shu Lin a LI Qing Shan a SONG Cui Ping a YIN Yuan Qi a② HUANG Xiao Ying b a 《结构化学》2000,(1)
1 INTRODUCTIONInthedevelopmentoftransitionmetalclusters,agreatmanytetrahedron-typechiralclustershavebeensynthesized.Oneimportantreasonisthatsuchclusterscanbepotentiallyusedasasymmetriccatalystsintheprocesswhichistrulycluster-cat-alyzed〔1,2〕.However,t… 相似文献
534.
1 INTRODUCTIONThe coordination chemistry oftransition metalcomplexeshasbecomeofremark able interestin recentyears.Sotoftetal.reported the structure of Ni( CH3CN) 6·Zn Cl4 〔1〕.Recently,Shyu etal.reported the structure of〔 Ni( bipy) 3〕〔 Fe( CN) 5 ( NO)〕· 3 H2 O〔2〕.Herein we reportthe structure oftitle complex〔 Ni( bipy) 3〕〔 Zn Cl4 〕 which issimilarto theformertwo complexes.Itisvery interesting to synthesizebimetallic compoundsfor both theoreticalstudy and practicalapp… 相似文献
535.
536.
1 INTRODUCTIONRecently,anumberofderivativesofbenzothiazepinehavebeenpreparedandstudiedfortheirpharmacologicalactivities〔15〕.Inourpreviouswork,wehaveincorporatedtheβlactamringinto1,5benzothiazepinebyreactionof1,5benzothiazepinewithsomeacylchlorid… 相似文献
537.
538.
Synthesis and Crystal Structure of [La(BTC)(H2O)6]n 总被引:1,自引:0,他引:1
WEN Yi-Hanga b c CHENG Jian-Kaia FENG Yun-Longb ZHANG Jiana c LI Zhao-Jia YAO Yuan-Gena② a 《结构化学》2005,24(12):1440-1444
1 INTRODUCTION desired topologies owing to their rich coordination modes[8~12] and we have been exploring the chemi- The assembly of metal-organic infinite frame- stry of coordination polymers constructed by tran- works via coordination of metal ions with multifunc- sition metals and benzoic multicarboxylic acids[13~16]. tional organic ligands is a field of increasing inte- In addition, lanthanide ions have high affinity for rest[1~4]. A rational designed and predictable coor- hard donor a… 相似文献
539.
Correlation between Chromatograph Capacity Factors and Structural Parameters of Indole Derivatives 总被引:1,自引:1,他引:0
1 INTRODUCTION thods with which the retention factor of a series of compounds could be predicted accurately[1, . In 2] The capacity factor of reversed phased high per- addition, indole and its derivatives have been widely formance liquid chromatograph (RP-HPLC) is a used in the synthesis of medical intermediate, co- basis for quantifying chromatograph peaks and se- loring agent and pesticide etc. Dai et al. have repor- parating compounds. And it has been universally ac- ted the relation… 相似文献
540.
ZHAO Dong-Baoa c JIANG Yan-Fengb XI Chan-Juanb LIU Xiu-Huac② WANG Han-Qinga a 《结构化学》2005,24(6):637-640
1 INTRODUCTION The whole body of herb of Artemisia Ordosica Kraschen (Artemisia genus of Compositae) has been long used to treat rheummarthritis, parotitis, intestinal obstruction as well as to stop bleeding in traditional Chinese medicine[1]. In our systematic studies of active metabolites, we have isolated seve- ral compounds from ethanol extracts of this plant[2], including flavones, flavanones, an isocoumarine, and capillarin. Coumarines commonly occur in na- tural plants as metabo… 相似文献