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Effi cacy of tricyclic antidepressants in irritable bowel syndrome:A meta-analysis 被引量:22
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作者 Roja Rahimi Shekoufeh Nikfar +1 位作者 Ali Rezaie Mohammad Abdollahi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第13期1548-1553,共6页
We aimed to evaluate the efficacy of tricyclic antidepressants(TCAs) as a therapeutic option for irritable bowel syndrome(IBS) through meta-analysis of randomized controlled trials.For the years 1966 until September 2... We aimed to evaluate the efficacy of tricyclic antidepressants(TCAs) as a therapeutic option for irritable bowel syndrome(IBS) through meta-analysis of randomized controlled trials.For the years 1966 until September 2008,PubMed,Scopus,Web of Science,and Cochrane Central Register of Controlled Trials were searched for double-blind,placebo-controlled trials investigating the effi cacy of TCAs in the management of IBS.Seven randomized,placebo-controlled clinical trials met our criteria and were included in the metaanalysis.TCAs used in the treatment arm of these trials included amitriptyline,imipramine,desipramine,doxepin and trimipramine.The pooled relative risk for clinical improvement with TCA therapy was 1.93(95% CI:1.44 to 2.6,P<0.0001).Effect size of TCAs versus placebo for mean change in abdominal pain score among the two studies was -44.15(95% CI:-53.27 to -35.04,P<0.0001).It is concluded that low dose TCAs exhibit clinically and statistically signifi cant control of IBS symptoms. 展开更多
关键词 Systematic review META-ANALYSIS tricyclic antidepressants Irritable bowel syndrome EFFICACY Clinical response Abdominal pain
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Geochemical significance of tricyclic and tetracyclic terpanes in source rock extracts from the Offshore Niger Delta Basin,Nigeria 被引量:2
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作者 Abiodun B.Ogbesejana Oluwasesan M.Bello +3 位作者 Tijjani Ali Uduma A.Uduma Kamaluddeen S.Kabo Oluwadurotimi O.Akintade 《Acta Geochimica》 EI CAS CSCD 2021年第2期184-198,共15页
Tricyclic and tetracyclic terpanes are important constituents of crude oil and source rock extracts.However,they have not been reported in the Offshore Niger Delta Basin,Nigeria.Thus,the present study investigated the... Tricyclic and tetracyclic terpanes are important constituents of crude oil and source rock extracts.However,they have not been reported in the Offshore Niger Delta Basin,Nigeria.Thus,the present study investigated the geochemical significance of tricyclic and tetracyclic terpanes in source rock extracts from the Offshore Niger Delta Bain,Nigeria with gas chromatography-mass spectrometry(GC-MS).The total relative abundances of tricyclic terpanes,C_(19)TT-C_(21)TT,and C_(23) TT in the rock samples ranged from 82.50 to 96.37%,50.08 to 74.17%,and 25.83 to 49.92%,respectively.These values showed the source rocks were formed from a mixed origin(terrestrial and marine).Among the tricyclic and tetracyclic terpanes identified in the rock extracts,the conventional(C_(20)TT,C_(23)TT,C_(24)TT,C_(24)TeT)and recent(Y1,X1,Z1)were more prominent than all others,indicating mixed input of terrigenous and marine organic matter.The C_(24)TT/C_(23)TT,C_(24)TeT/(C_(24)TeT+C_(26)TT),C_(19)TT/C_(23)TT,C_(20)TT/C_(23)TT,C_(25)TT/C_(24)TeT,C_(25)TT/C_(26)TT,C_(19)TT/C_(20)TT,C_(24)TeT/C_(26)TT,Z1/(Z1+C_(24)TT),and Y1/(Y1+C_(24)TT)in the rock samples range from 0.33 to 1.30,0.76 to 0.90,0.18 to 0.73,0.34 to 1.05,0.33 to 1.74,0.30 to 1.39,0.31 to0.89,1.66 to 4.33,0.36 to 0.83,and 0.34 to 0.79,respectively.These values further showed that the rock samples were formed from mixed input of terrigenous and marine organic matter and deposited under oxic to suboxic conditions in lacustrine-fluvial/deltaic environments.Also,the C_(24)TeT/C_(20)-26TT,C_(24)TeT/C_(30)HOP,and C_(23)TT/C_(30)HOP ranged from 0.16 to 0.45,0.02 to 0.42,and 0.01 to 0.48,respectively.This range of values suggests that source rocks were within immature to early mature stage.Thus,this study showed that tricyclic and tetracyclic terpanes were effective in determining the origin,depositional environments,and thermal maturity of source rocks in the Niger Delta Basin,Nigeria. 展开更多
关键词 tricyclic terpanes Tetracyclic terpanes Source rocks Niger delta Gas chromatography-mass spectrometry(GC-MS)
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Tricyclic Sesquiterpene from Laurencia Majuscula 被引量:2
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作者 XU Xiao Hua ZENG Long Mei SU Jing Yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第2期84-86,共3页
TricyclicSesquiterpenefromLaurenciaMajuscula*XUXiao-Hua,ZENGLong-MeiandSUJing-Yu**(DepartmentofChemistry,Zho... TricyclicSesquiterpenefromLaurenciaMajuscula*XUXiao-Hua,ZENGLong-MeiandSUJing-Yu**(DepartmentofChemistry,ZhongshanUniversity,... 展开更多
关键词 tricyclic sesquiterpene Laurencia majuscula TERPENOID Majusin
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Study on the Total Synthesis of Et 743 and its Analogues: Synthesis of a Tricyclic Intermediate and its 11-Epimer 被引量:1
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作者 Ye Feng TANG, Zhan Zhu LIU, Shi Zhi CHENInstitute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union MedicalCollege, Beijing 100050 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第10期996-998,共3页
The tricyclic compound 1, a key intermediate of the pentacyclic core of Et 743 and its analogues, was synthesized. Its 11-epimer was found as the product of racemization when BOP was used as the coupling agent, but no... The tricyclic compound 1, a key intermediate of the pentacyclic core of Et 743 and its analogues, was synthesized. Its 11-epimer was found as the product of racemization when BOP was used as the coupling agent, but not when BOP-C1 used in the same reaction. The stereochemistry of both isomers was confirmed on basis of the 1H NMR and NOE-difference spectra. 展开更多
关键词 Et 743 tricyclic compound synthesis stereochemistry.
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An Efficient Synthesis of Ethyl 7-Chloro-6-fluoro-l-methyl-4-oxo-1, 4-dihydro-[1, 3]thiazeto[3, 2-a]quinoline-3-carboxylate as Intermediate of the Prulifloxacin Containing Tricyclic Fluoroquinolone 被引量:1
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作者 Shu Tao MA Hong Xiang LOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期714-716,共3页
Novel ethyl 7-chloro-6-fluoro-l-methyl-4-oxo-1, 4-dihydro-[1, 3]thiazeto[3, 2-a]quino- line-3-carboxylate 2 was prepared from 3-chloro-4-fluoroaniline in eight steps. It can be used as a new intermediate for the synth... Novel ethyl 7-chloro-6-fluoro-l-methyl-4-oxo-1, 4-dihydro-[1, 3]thiazeto[3, 2-a]quino- line-3-carboxylate 2 was prepared from 3-chloro-4-fluoroaniline in eight steps. It can be used as a new intermediate for the synthesis of tricyclic fluoroquinolones. 展开更多
关键词 Synthesis tricyclic fluoroquinolone.
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Study on the Total Synthesis of Hainanolide-Construction of Tricyclic Intermediate(I)
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作者 Lu Yan ZHANG Shi Zhi CHEN +3 位作者 Dong WEI Liang HUANG Ji Jie CHAI Cun Heng HE(Institute of Materia Medica Chinese Academy of Medical Sciences.Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第10期892-893,共2页
Tricyclic compounds (4b-endo) and (4b-exo) are synthesized as the plausible intermediates of the total synhthesis of hainanolide by Lewis acid catalyzed intramolecular DielsAlder (IMDA) reaction.
关键词 SYNTHESIS TOTAL INTERMEDIATE tricyclic Construction Hainanolide
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Crystal Structure of a Tricyclic Compound C_(20)H)(28)O_6 Obtained through IMDA Reaction
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作者 CHAI Ji-Jie HE Cun-Heng +3 位作者 LI Ming ZHANG Lu-YanCHEN Shi-Zhi YANG Wen-Qian HUANG Liang(Institute of Materia Medica, Chinese Academy of Medical Sciences & PekingUnion Medical College, No. 1 Xian Nong Tan Street, Beijing 100050) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第5期345-348,共4页
The tricyclic compoun d (2) C20H28O6 has been synthesized through thereaction of IMDA. The crystals of the title compound(2A) were crystallized from etherin monoclinic space group C2 with a unit cell: a = 11. 301 (2),... The tricyclic compoun d (2) C20H28O6 has been synthesized through thereaction of IMDA. The crystals of the title compound(2A) were crystallized from etherin monoclinic space group C2 with a unit cell: a = 11. 301 (2), b=11-.863 (3 ), c =29. 59 (1) , β= 101. 02(5)°, V=3894. 246, Dc=1.2413 g/cm3, Z=8, F(000)=1568, Mr= 364. 00 R=0.055, R2=0. 055, μ= 535 cm-1, S(GOF) =0. 571. Theconfiguration of C2a-H in the title compound was found to be contrary to what wasexpected and a possible mechanism of reaction was proposed. 展开更多
关键词 IMDA REACTION CRYSTAL structure tricyclic COMPOUND
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Study on the Total Synthesis of Hainanolide (Ⅱ)──An Unexpected Hydroperoxide Containing Tricyclic Skeleton
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作者 Lu Yan ZHANG Wen Qian YANG +1 位作者 Shi Zhi CHEN Liang HUANG(Institute of Materia Medica, Chinese Academy of Medical Sciences,Peking Union Medical College,Beijing,100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第1期15-16,共2页
An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed b... An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed by spectra and X-Ray diffraction analysis, An 1O2oxidation mechanism was proposed. 展开更多
关键词 ppm An Unexpected Hydroperoxide Containing tricyclic Skeleton Study on the Total Synthesis of Hainanolide
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The Inertia Indexes of One Special Kind of Tricyclic Graphs
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作者 Haicheng Ma Chengling Xie 《Applied Mathematics》 2019年第1期11-18,共8页
Let G be a graph and A=(aij)n×n be the adjacency matrix of G, the eigenvalues of A are said to be the eigenvalues of the graph G, and to form the spectrum of this graph. The numbers of positive, negative and zero... Let G be a graph and A=(aij)n×n be the adjacency matrix of G, the eigenvalues of A are said to be the eigenvalues of the graph G, and to form the spectrum of this graph. The numbers of positive, negative and zero eigenvalues in the spectrum of the graph G are called positive and negative inertia indexes and nullity of the graph G, are denoted by p(G), n(G), η(G), respectively, and are collectively called inertia indexes of the graph G. The inertia indexes have many important applications in chemistry and mathematics. The purpose of the research of this paper is to calculate the inertia indexes of one special kind of tricyclic graphs. A new calculation method of the inertia indexes of this tricyclic graphs with large vertices is given, and the inertia indexes of this tricyclic graphs with fewer vertices can be calculated by Matlab. 展开更多
关键词 tricyclic GRAPHS Positive INERTIA INDEX Negative INERTIA INDEX NULLITY
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The role of selective serotonin reuptake inhibitors and tricyclic antidepressants in addressing reduction of Meniere's disease burden:A scoping review
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作者 Alexander A.Missner Mana Sheykhsoltan +1 位作者 Amir Hakimi Michael Hoa 《World Journal of Otorhinolaryngology-Head and Neck Surgery》 CAS CSCD 2024年第3期206-212,共7页
Objective:To assess the effect of selective serotonin reuptake inhibitors(SSRIs)and tricyclic antidepressants(TCAs)in reducing vertigo,tinnitus,and hearing loss among patients with Meniere's disease(MD).Data Sourc... Objective:To assess the effect of selective serotonin reuptake inhibitors(SSRIs)and tricyclic antidepressants(TCAs)in reducing vertigo,tinnitus,and hearing loss among patients with Meniere's disease(MD).Data Sources:The following databases were utilized in this scoping review:Ovid Medline,PubMed-NCBI,CINAHL,Cochrane Library,Web of Science,and Clinicaltrials.gov.Method:Studies were identified through the following search phrases:"serotonin specific reuptake inhibitors"OR"tricyclic antidepressants"AND"Meniere's disease."References from included manuscripts were examined for possible inclusion of additional studies.Results:The literature search yielded 23 results,which were screened by three independent reviewers.Seventeen studies and three duplicates were excluded.An examination of references from the included studies yielded two additional publications.A total of four published studies assessing SSRIs and TCAs among 147 patients with MD were ultimately included.Four studies described significant reductions in vertigo attack frequency among patients treated with either SSRIs or TCAs compared to their pretreatment baseline.Three studies assessed the drugs'effects on hearing,of which none found a significant difference among patients treated with SSRIs or TCAs.One study found a significant decrease in patient-reported tinnitus following treatment with TCAs or SSRIs compared to their pretreatment baseline.Conclusions:Data exploring SSRIs and TCAs among patients with MD suggests that these medications may reduce the frequency of tinnitus and vertigo,although there was significant heterogeneity in outcome reporting.There remains a need for larger-scale prospective studies that emphasize objective data to evaluate their effective-ness in reducing common MD symptoms. 展开更多
关键词 aural fullness clinical trials Meniere's disease scoping review sensorineural hearing loss serotonin specific reuptake inhibitors tricyclic antidepressants VERTIGO
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Construction of Angularly Fused Tricyclic Compounds via Photo-induced Radical Cascade Cyclization
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作者 Mengqin Hu Wei Cao +6 位作者 Zhen Wang Yan Hao Ganxing Huang Yuqiao Zhou Song Qin Shaomin Fu Bo Liu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2023年第19期2502-2506,共5页
Photo-induced electron transfer (PET) of silyl enol ethers has been employed to synthesize several fused ring systems. However, the method has limited applicability due to its narrow substrate scope, low product yield... Photo-induced electron transfer (PET) of silyl enol ethers has been employed to synthesize several fused ring systems. However, the method has limited applicability due to its narrow substrate scope, low product yields, unsatisfactory stereo- and regioselectivity. Herein, we report a PET-triggered cascade reaction of silyl enolates that leads to the formation of angularly fused tricyclic scaffolds. The reaction exhibits broad substrate scope and excellent stereoselectivity. The regio- and stereoselectivity of this cascade reaction is elucidated via DFT calculation and conformational analysis. 展开更多
关键词 CYCLIZATION RADICAL tricyclic compounds PHOTOCATALYSIS ENOLS Fused-ring systems Domino reactions Regioselectivity
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Discovery and development of tricyclic matrinic derivatives as anti-diabetic candidates by AMPKαactivation
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作者 Yinghong Li Yuanhui Zhang +12 位作者 Tianyu Niu Yudong Pang Yulong Shi Qingxuan Zeng Jingpu Zhang Jingyang Zhu Xiuli Zhong Yanxiang Wang Yan Wang Sheng Tang Weijia Kong Danqing Song Jiandong Jiang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第1期289-294,共6页
We found compound 12N-p-trifluoromethylbenzenesulfonyl matrinane(1)was a potent anti-diabetic agent.Thirty-five tricyclic matrinic derivatives were synthesized and determined for their stimulatory effects on glucose c... We found compound 12N-p-trifluoromethylbenzenesulfonyl matrinane(1)was a potent anti-diabetic agent.Thirty-five tricyclic matrinic derivatives were synthesized and determined for their stimulatory effects on glucose consumption in L6 myotubes,taking 1 as the lead.In high-fat diet(HFD)and STZ induced diabetic mice,9a significantly lowers blood glucose,improves glucose tolerance,and especially alleviates diabetic nephropathy and islet damage.Mechanism study indicates that 9a simultaneously targets mitochondrial complex I to increase AMP/ATP ratio,as well as liver kinase B1(LKB1)and calcium/calmodulindependent protein kinase(Ca MKK),which synergistically activates AMPKαand then stimulates glucose transporter 4(GLUT4)membrane translocation and 2-deoxyglucose(2-DG)uptake to exert anti-diabetic efficacy.Therefore,compound 9a with a novel structure is a promising anti-diabetic candidate with the advantage of multiple-target mechanism,worthy of further investigation. 展开更多
关键词 tricyclic matrinic derivatives Glucose consumption Diabetes mellitus AMP-activated protein kinase(AMPK)
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Stereoselective Synthesis of (-)-Chloramphenicol, (+)-Thiamphenicol and (+)-Sphinganine via Chiral Tricyclic Iminolactone 被引量:2
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作者 Qiong Li Hongbo Zhang +1 位作者 Chenguang Li Pengfei Xu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第1期149-153,共5页
The stereoselective syntheses of (-)-chloramphenicol, (+)-thiamphenicol and (+)-sphinganine are described. The two continuous chiral centers within three target molecules were constructed through aldol reactio... The stereoselective syntheses of (-)-chloramphenicol, (+)-thiamphenicol and (+)-sphinganine are described. The two continuous chiral centers within three target molecules were constructed through aldol reaction of chiral tricyclic iminolactone and aldehyde. 展开更多
关键词 β-hydroxy-a-amino alcohol tricyclic iminolactone total synthesis
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Discovery and development of synthetic tricyclic pyrroloquinone (TPQ) alkaloid analogs for human cancer therapy 被引量:1
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作者 Wei Wang Bhavitavya Nijampatnam +1 位作者 Sadanandan E. Velu Ruiwen Zhang 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2016年第1期1-15,共15页
Natural products and their derivatives repre- sent a rich source for the discovery and development of new cancer therapeutic drugs. Bioactive components derived from natural sources including marine compounds have bee... Natural products and their derivatives repre- sent a rich source for the discovery and development of new cancer therapeutic drugs. Bioactive components derived from natural sources including marine compounds have been shown to be effective agents in the clinic or in preclinical settings. In the present review, we present a story of discovery, synthesis and evaluation of three synthetic tricyclic pyrroloquinone (TPQ) alkaloid analogs as cancer therapeutic agents. Chemical synthesis of these compounds (BA-TPQ, TBA-TPQ, and TCBA-TPQ) has been accomplished and the mechanisms of action (MOA) and structure-activity relationships (SAR) have been investigated. In the past, the complexity of chemical synthesis and the lack of well-defined MOA have dampened the enthusiasm for the development of some makaluvamines. Recent discovery of novel molecular targets for these alkaloids (unrelated to inhibition of Topoisomerase II) warrant further consideration as clinical candidates in the future. In addition to the establishment of novel synthetic approaches and demonstration of in vitro and in vivo anticancer activities, we have successfully demonstrated that these makaluvamines attack several key molecular targets, including the MDM2-p53 pathway, providing ample opportunities of modulating the compound structure based on SAR and the use of such compounds in combination therapy in the future. 展开更多
关键词 synthesis marine drugs tricyclic pyrroloqui- none alkaloid cancer therapy MDM2 p53
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Tricyclic aromatic diterpanes found in the Tertiary sediments and their geochemical significance
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作者 SHENG Guoying FU Jiamo +1 位作者 SONG Yitao PENG Ping’an 《Chinese Science Bulletin》 SCIE EI CAS 2000年第S1期11-15,共5页
One monoaromatic tricyclic diterpane and two aromatic tricyclic diterpanes were found in three low-maturity source rocks and five crude oils of the Tertiary Shahejie Formation in Shengli Oil Field. The compounds found... One monoaromatic tricyclic diterpane and two aromatic tricyclic diterpanes were found in three low-maturity source rocks and five crude oils of the Tertiary Shahejie Formation in Shengli Oil Field. The compounds found include C19H28 (m/z 145, M+ 256) ring-C monoaromatic tricyclic terpane, C17H20 (m/z 209, M+ 224) and C18H22 (m/z 223,M+ 238) rings-B,C diaromatic diterpanes. The results show that these compounds are biomarkers of immature organic matter with a stability sequence of C18H22 】 C17H20 】 C19H28. The cleavage of ring-D of pentacyclic triterpanoids, such as oleanene, hopene, fernene, ursene, in the early stage of diagenesis may be one of the origin pathways of rings-B, C diaromatic tricyclic diterpanes. 展开更多
关键词 monoaromatic tricyclic TERPANE diaromatic tricyclic diterpanes TERTIARY Shahejie Formation IMMATURE source rocks CRUDE oil.
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Pulse radiolysis of one-electron oxidation of rare tricyclic nucleoside derivative
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作者 赵红卫 江致勤 +4 位作者 窦大营 吴铁一 王文锋 杜小行 姚思德 《Science China Chemistry》 SCIE EI CAS 2003年第2期144-151,共8页
One-electron oxidation of N-4-desmethylwyosine (dYt), a derivative of rare tricyclic nucleoside wyosine with several oxidative radicals, has been studied by using pulse radiolysis. The transient spectra of the radical... One-electron oxidation of N-4-desmethylwyosine (dYt), a derivative of rare tricyclic nucleoside wyosine with several oxidative radicals, has been studied by using pulse radiolysis. The transient spectra of the radicals dYt˙+ and dYt(-H)˙ and the pK a of the radical cation were measured. The rate constants of reactions of dYt with SO 4 ˙? and CO 3 ˙? radicals have been determined and related reaction mechanisms were discussed. 展开更多
关键词 RARE tricyclic NUCLEOSIDE derivative ONE-ELECTRON oxidation pulse radiolysis radical transient absorption spectra.
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Asymmetric synthesis of ABC tricyclic systems in Daphniphyllum alkaloid
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作者 Huijing Wang Qiuyan Dong +1 位作者 Qinxia Xie Pei Tang 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第3期685-688,共4页
Efficient synthetic routs for the direct and rapid construction of[5-6-6]ABC tricyclic systems of daphmanidin A-type and calyciphylline A-type alkaloids have been successfully developed.For the daphmanidin A-type,the ... Efficient synthetic routs for the direct and rapid construction of[5-6-6]ABC tricyclic systems of daphmanidin A-type and calyciphylline A-type alkaloids have been successfully developed.For the daphmanidin A-type,the synthesis of[5-6-6]tricyclic framework utilize a HCl-mediated intramolecular Aldol reaction to construct the bicyclo[2.2.2]octane core and a thermal condensation to afford the ABC ring system.In addition,for the calyciphylline A-type,an improved synthesis of ABC[5-6-6]tricyclic system was developed,featuring an introduction of methyl ester group at C2 before the Pd-catalyzed intramolecular oxidative alkylation to construct the desired bowl-shape tricyclic core with stereochemical control. 展开更多
关键词 Daphniphyllum ALKALOID Calyciohylline N 21-Deoxymacropodumine D ABC tricyclic framework INTRAMOLECULAR ALDOL reaction PD-CATALYZED INTRAMOLECULAR oxidative alkylation
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Synthesis of ACE tricyclic systems of daphnicyclidin A and dehy-droxymacropodumine A
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作者 Qi Wang Chao Zhang Jun Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第7期1906-1910,共5页
The synthesis of the ACE tricyclic system of daphnicyclidin A and dehydroxymacropodumine A are developed.The key reactions include an efficient aldol reaction to introduce chiral fragment 33 for further construction o... The synthesis of the ACE tricyclic system of daphnicyclidin A and dehydroxymacropodumine A are developed.The key reactions include an efficient aldol reaction to introduce chiral fragment 33 for further construction of piperidine ring B and seven-membered ring C, a nucleophilic addition of lithium pentene to aldehyde for installation of ring E,and a photocatalytic decarboxylation conjugate addition to construct ring C. 展开更多
关键词 tricyclic system Daphnicyclidin A Dehydroxymacropodumine A Photocatalytic decarboxylation Conjugate addition
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SAR of tricyclic sulfones as γ-secretase inhibitors
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作者 COLE David ASBEROM Ted +12 位作者 BARA Tom BENNETT Chad BURNETT Duane A. CLADER John DOMALSKI Martin GREENLEE William J. HYDE Lynn JOSIEN Hubert McBRIAR Mark McKITTRICK Brian PISSARNITSKI Dmitri RAJAGOPALAN Murali SASIKUMAR Thavalakulamgara 《Science China Chemistry》 SCIE EI CAS 2011年第11期1688-1701,共14页
Novel tricyclic sulfones as γ-secretase inhibitors have been reported by this laboratory for the treatment of Alzheimer's disease. Compounds in this series have comparable or better in vitro activities and in viv... Novel tricyclic sulfones as γ-secretase inhibitors have been reported by this laboratory for the treatment of Alzheimer's disease. Compounds in this series have comparable or better in vitro activities and in vivo efficacies than sulfonamide analogues re- ported previously by this laboratory. Based on the previously reported tricyclic sulfone scaffold, additional SAR studies of C ring were carried out. Various C-ring structures including cyclohexane, pyran, and piperidine were tolerated. Additionally, the 7- and 8- positions of the C-ring were identified as the best sites to introduce substituent for modulating the pharmacokinetic properties of compounds from this series. 展开更多
关键词 tricyclic sulfones T-secretase Alzheimer's disease INHIBITORS
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Ordering of Spectral Moments of Tricyclic Graphs with Given Bases
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作者 WU Yaping FAN Qiong 《Wuhan University Journal of Natural Sciences》 CAS 2014年第3期185-188,共4页
The spectral moments are the important algebraic invariants of graphs.In this paper,on the basis of definitions of tricyclic graphs,base and the sequence of spectral moments,respectively,we study tricyclic graphs with... The spectral moments are the important algebraic invariants of graphs.In this paper,on the basis of definitions of tricyclic graphs,base and the sequence of spectral moments,respectively,we study tricyclic graphs with given bases on the lexicographical order of the spectral moments sequence,and find the last and the first graphs.The results is very helpful for studying all tricyclic graphs ordering by spectral moments. 展开更多
关键词 spectral moment tricyclic graph base
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