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Rheological properties of novel viscoelastic micelle systems containing anionic-nonionic Dimeric surfactant

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Journal of Central South University 2008年第S1期15卷 176-180页

作者：方波曹丹红江体乾 School of Chemical Engineerring East China University of Science and Technology

The viscoelastic micelle systems formed by novel anionic-nonionic Dimeric surfactant and conventional cationic surfactant cetyltrimethylammonium(1631) were studied.The viscoelasticity,thixotropy,flow curves and constitutive equation for the novel viscoelastic micelle systems were investigated.The results show that the micelle systems possess viscoelasticity,thixotropy,and shear thinning property.Some micelle systems possess hysteresis loops showing both viscoelasticity and thixotropy.It is proved that the flow curves are characterized by the co-rotational Jeffreys constitutive equation correctly.

关键词： Dimeric surfactant viscoelastic micelle clean fracturing fluid constitutive equation

Synthesis of Dimeric estradiol enzyme model containing imidazolyl and study on its catalytic efficiency in hydrolysis of carboxylates and phosphates

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Chinese Journal of Chemistry 1997年第5期15卷 438-442页

作者： Yan, JM Xie, RG Zhao, HM Wu, DX Xia, PF Sichuan Univ Dept Chem Chengdu 610064 Sichuan Peoples R China Sichuan Normal Coll Dept Chem Chengdu 610041 Sichuan Peoples R China

Dimeric estradiol enzyme model (2) was synthesized by etherification of 2,4-bis(N-imidazolylmethyl)-17β-estradiol (1) with 1,3-dibromopropane in the presence of anhydrous K2CO3. Hydrolysis of carboxylates and phosphates catalyzed by the model showed Michaelis-Menten kinetic behavior. Hydrophobic interaction between the model and ester accelerates the hydrolysis markedly, rate enhancement of up to 65 and 285 fold, relative to imidazole, is observed.

关键词： Dimeric estrogen enzyme model compound catalytic hydrolysis carboxylate phos- phate

Erratum to:New Dimeric and seco-Abietane Diterpenoids from Salvia wardii

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Natural Products and Bioprospecting 2015年第3期5卷 175-175页

作者： Qiu-Li Xiao Fan Xia Xing-Wei Yang Yang Liao Li-Xin Yang Yu-Kun Wei Xian Li Gang Xu School of Pharmaceutical Science and Yunnan Key Laboratory of Pharmacology of Natural Products Kunming Medical UniversityKunming 650500YunnanPeople’s Republic of China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China Shanghai Chenshan Plant Science Research Center Chinese Academy of SciencesBeijingPeople’s Republic of China

Erratum to:Nat.Prod.Bioprospect.(2015)5:77–82 DOI 10.1007/s13659-015-0054-6 In the HTML version of the original publication,the graphical abstract was inadvertently omitted.The graphical abstract is given in this er... 详细信息

关键词： graphical Dimeric d.

Dimeric Dipeptide Mimetics of NGF and BDNF Are Promising Agents for Post-Stroke Therapy

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Journal of Biomedical Science and Engineering 2018年第5期11卷 100-107页

作者： Polina Povarnina Tatyana A. Gudasheva Sergey B. Seredenin Department of Medicinal Chemistry Federal State Budgetary Institution “Research Zakusov Institute of Pharmacology” Moscow Russia Department of Pharmacogenetics Federal State Budgetary Institution “Research Zakusov Institute of Pharmacology” Moscow Russia

The Dimeric dipeptide mimetics of the brain derived neurotrophic factor (BDNF) loops 1 and 4 and nerve growth factor (NGF) loop 4 were designed and synthesized at the Zakusov Research Institute of Pharmacology. There are respectively bis-(N-monosuccinyl-L-methionyl-L-serine) heptamethylenediamide(GSB-214), bis-(N-monosuccinyl-L-seryl-L-lysine) hexamethylenediamide (GSB-106) and bis-(N-monosuccinyl-L-glutamyl-L-lysine) hexamethylenediamide (GK-2). All of the ob-tained compounds activated a corresponding specific NGF or BDNF tyrosine kinase receptor (TrkA or TrkB), but had different postreceptor signaling patterns. GSB-106 activated the ERK and AKT, whereas GSB-214 and GK-2 only activated the AKT kinase. Here we report a comparative analysis of neuroprotective activity of these dipeptides in a model of ischemic stroke induced by transient middle cerebral artery occlusion (MCAO). The all three Dimeric dipeptides showed a statistically significant decrease of infarct volumes with the treatment beginning 4 hour after surgery. In the experiment with BDNF mimetics, GSB-106 reduced this volume by 66% and GSB-214 by 26%. NGF GK-2 reduced the cerebral infarct volume by 45%. Thus, BDNF mimetic, which activated both the ERK and AKT, and NGF mimetic, which selectively activated PI3K/AKT, showed high neuroprotective efficacy. In addition, we studied neuroprotective effects of GK-2 at the beginning of the treatment 6, 8 and 24 hours after reperfusion. The neuroprotective effect of GK-2 persisted in all these conditions. The effectiveness of GK-2 at a delayed start of administration suggests that the dipeptide has neuroregenerative properties. The results obtained suggest a potential role for the Dimeric dipeptide NGF and BDNF mimetics as therapeutic agents useful in the treatment of a stroke.

关键词： NGF BDNF Dimeric Dipeptide Mimetics Stroke

Antinociceptive grayanane-derived diterpenoids from flowers of Rhododendron molle

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Acta Pharmaceutica Sinica B 2020年第6期10卷 1073-1082页

作者： Yong Li Yuxun Zhu Zhaoxin Zhang Li Li Yunbao Liu Jing Qu Shuanggang Ma Shishan Yu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical College

Twelve new grayanoids(1-12)along with five known compounds were isolated from flowers of Rhododendron molle.Their structures were fully characterized using a combination of spectroscopic analyses,computational calculations,and single crystal X-ray diffraction.Rhomollone A(1)possesses an unprecedented 5/6/6/5 tetra-cyclic ring system(B-nor grayanane)incorporating a cyclopentene-1,3-dione scaffold.Rhodomollein XLIII(2)is a Dimeric grayanoid,containing a novel 14-membered heterocyclic ring with a C2 symmetry axis.The antinociceptive activities of compounds 3,4,6,7,and 12-17 were evaluated by an acetic acid-induced writhing test.Among them,compounds 3,7,12,15 and 16 displayed significant antinociceptive activities at a dose of 20 mg/kg with inhibition rates ranging from41.9%to 91.6%.Compounds 6 and 13 inhibited 46.0%and 39.4%of the acetic acid-induced writhes at a dose of 2 mg/kg,while compound 17 inhibited 34.3%of the writhes at a dose of 0.4 mg/kg.

关键词： Rhododendron molle Diterpenoid Grayanane Dimeric Antinociceptive Analgesic

INACTIVATION OF CREATINE KINASE AT LOW GUANIDINE CONCENTRATIONS IS NOT DUE TO THE DISSOCIATION OF THE Dimeric ENZYME

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Chinese Science Bulletin 1989年第12期34卷 1036-1040页

作者：刘国华侯立向邹承鲁 Laboratory of Molecular Enzyraology Institute of Biophysics Academia Sinica Beijing

Ⅰ. INTRODUCTIONIn earlier publications from this laboratory it has been reported that during the denaturation of creatine kinase (ATP: creatine phosphotransferase EC 2.***.3.2) by guanidine and urea, the inactivation of the enzyme takes place at denaturant concentrations much lower than necessary to bring about noticeable conformational changes as detected by conventional physicochemical, methods. Moreover, at the same denaturant concentration, the inactivation rates are several orders of magnitude

关键词： creatine kinase guanidine Dimeric enzyme.

Hel photoelectron spectroscopic (PES) and quantum chemistry study on the Dimeric compound of 2(5H) furanone

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Science China Chemistry 1997年第6期40卷 657-662页

作者：郑世钧王晓慧孟令鹏曹晓燕王殿勋 Department of Chemistry Hebei Normal UniversityShijiazhuang 050091China Institute of Chemistry Chinese Academy of SciencesBeijing 100080China

The HeI photoelectron (PE) spectra of both 2(5H) furanone and its trans-chair-dimenc-compound (t-c-DFN) are reported.The assignment of the PES bands is made on the basis of band shapes,the PES results of the molecules which have the similar atomic groups,and the restricted Hartree-Fock (RHF) calculations for the molecules studied.From the results of both PES experimental and theoretical calculations,it is proved that the ionization potential (IPs) of the HOMO for the dimenc-compound is lower than that of the HOMO for the monomer.And the total energy computed for the t-c-DFN is the lowest in the four possible configurations of Dimeric-compounds of 2(5H) furanone Therefore the synthesis of t-c-DFN is also the easiest.

关键词： Dimeric 2(5H) furanone Hel photoelectron spectroscopy ab initio method

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新一代表面活性剂:Geminis

化学进展 1999年第4期11卷 348-357页

作者：赵剑曦福州大学化学系福州350002

表面活性剂Ｇｅｍｉｎｉ（或称ｄｉｍｅｒｉｃ）是由两个单链单头基普通表面活性剂在离子头基处通过化学键联接而成，因而阻抑了表面活性剂有序聚集过程中的头基分离力，极大提高了表面活性。与当前为提高表面活性而进行的大量尝试... 详细信息

表面活性剂Ｇｅｍｉｎｉ（或称ｄｉｍｅｒｉｃ）是由两个单链单头基普通表面活性剂在离子头基处通过化学键联接而成，因而阻抑了表面活性剂有序聚集过程中的头基分离力，极大提高了表面活性。与当前为提高表面活性而进行的大量尝试，如添加盐类、提高温度或将阴离子表面活性剂与阳离子表面活性剂混合相比较，Ｇｅｍｉｎｉ表面活性剂是概念上的突破，因而被誉为新一代的表面活性剂。

关键词：表面活性剂联接基因 Geminis Dimeric

Synthesis and Crystal Structure of Cupric Complex with Propylenebis(oxamic acid)

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Chinese Journal of Structural Chemistry 1999年第2期18卷 56-60页

作者： Zhu, ZC Xu, Z Huang, XY Nanjing Univ Inst Coordinat Chem State Key Lab Coordinat Chem Nanjing 210093 Peoples R China Chinese Acad Sci Fujian Inst Res Struct Matter State Key Lab Struct Chem Fujian 350002 Peoples R China

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｃｏｏｒｄｉｎａｔｉｏｎｃｈｅｍｉｓｔｒｙｏｆｏｘａｍｉｄｅｓａｎｄｓｕｂｓｔｉｔｕｔｅｄｏｘａｍｉｄｅｓｉｓｏｆｉｍｐｏｒｔａｎｃｅｔｏａｗｉｄｅｖａｒｉｅｔｙｏｆｃｈｅｍｉｃａｌ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｃｏｏｒｄｉｎａｔｉｏｎｃｈｅｍｉｓｔｒｙｏｆｏｘａｍｉｄｅｓａｎｄｓｕｂｓｔｉｔｕｔｅｄｏｘａｍｉｄｅｓｉｓｏｆｉｍｐｏｒｔａｎｃｅｔｏａｗｉｄｅｖａｒｉｅｔｙｏｆｃｈｅｍｉｃａｌ〔１〕，ｂｉｏｌｏｇｉｃａｌ〔１〕...

关键词： Dimeric complexes X ray structure copper complex