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Studies on the esterifications of 9-(hydroxyimino)-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one with acid chlorides under different conditions
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作者 Ru Shu Sun Yang Wang Peng Xia 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第7期791-794,共4页
The esterifications of 9-(hydroxyimino)-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one (4) with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as t... The esterifications of 9-(hydroxyimino)-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one (4) with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as the acid scavenger, whereas the reactions gave unexpected 8-substituted products N-(8-chloro-4-methyl-2-oxo-2H-furo-[2,3-h]chromen-9-yl)amides (5a-c) and 4-methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloates (6d-e) by using excessive acid chlorides. The structures of 10 new compounds were determined by 1H NMR, 13C NMR, MS and HRMS, and the possible mechanism for the formation of unexpected products 5a--c and 6d-e was also proposed. 展开更多
关键词 9-(Hydroxyirnino)-4-methyl-8 9-dihydrofuro[2 3-h]chromen-2-one Oxime-ester N-(8-Chloro-4-methyl-2-oxo-2H-furo[2 3-h]chro-men-9-yl)amide 4-methyl-2 9-dioxo-8 9-dihydro-2H-furo[2 3-h]chromen-8-ylcarboxyloate
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A New Benzylisoquinoline Alkaloid from Sabia parviflora 被引量:6
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作者 Jin CHEN Bin CHEN +1 位作者 Jun TIAN Feng E WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第5期426-427,共2页
A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the... A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the basis of spectral analysis. 展开更多
关键词 Sabia parviflora benzylisoquinoline alkaloid 1 2 3 4-tetrahydro-5-hydroxyl-8- methoxyl-2-methyl-4'-methoxyl-benzylisoquinoline.
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Absorption characteristics of new solvent based on a blend of AMP and 1,8-diamino-p-menthane for CO_2 absorption 被引量:2
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作者 Sang-Sup Lee Seong-Man Mun +3 位作者 Won-Joon Choi Byoung-Moo Min Sang-Won Cho Kwang-Joong Oh 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第5期897-902,共6页
Aqueous 1,8-diamino-p-menthane (KIER-C3) and commercially available amine solutions were tested for CO2 absorption. A 2-amino-2-methyl-1-propanol (AMP) solution with an addition of KIER-C3 showed 9.3% and 31.6% hi... Aqueous 1,8-diamino-p-menthane (KIER-C3) and commercially available amine solutions were tested for CO2 absorption. A 2-amino-2-methyl-1-propanol (AMP) solution with an addition of KIER-C3 showed 9.3% and 31.6% higher absorption rate for CO2 than the AMP solution with an addition of monoethanolamine (MEA) and ammonia (NH3), respectively. The reaction rate constant for CO2 absorption by the AMP/KIER-C3 solution was determined by the following equation: k2,AMP/C3 = 7.702×106 exp (-2248.03/T). A CO2 loading ratio of the AMP/KIER-C3 solution was also 2 and 3.4-times higher than that of the AMP/NH3 solution and the AMP/MEA solution, respectively. Based on the experimental results, KIER-C3 may be used as an excellent additive to increase CO2 absorption capability of AMP. 展开更多
关键词 carbon dioxide absorption rate and capacity 1 8-diamino-p-menthane 2-amino-2-methyl-1-propanol
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A New Halogenated Biindole and A New Apo-carotenone from Green Alga Chaetomorpha basiretorsa Setchell 被引量:6
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作者 DaYongSHI LiJunHAN +5 位作者 JieSUN ShuaiLI SuJuanWANG YongChunYANG XiaoFAN JianGongSHI 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第6期777-780,共4页
关键词 Green alga Chaetomorpha basiretorsa Sethcell 4 4′-dichloro-5 5′-dibromo-7 7′-di- methoxy-2 2′-bi-1H-indole 1′S* 4′R*-8-(4′-hydroxy-2 6′ 6′-trimethylcyclohex-2-enyl)-6-methyl- oct-3E 5E 7E-trien-2-one.
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UPLC-Q/TOF法同时定性定量分析滇芹药材中主要化学成分 被引量:8
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作者 秦伟瀚 冉继春 +4 位作者 叶良红 花雷 王云红 郭延垒 阳勇 《中草药》 CAS CSCD 北大核心 2018年第15期3576-3582,共7页
目的建立UPLC-Q/TOF法同时定性、定量分析滇芹中主要化学成分。方法采用超高效液相色谱串联飞行时间质谱法进行分析,色谱柱为Agilent Poroshell 120 Hilic,流动相为乙腈-0.1%甲酸水溶液,梯度洗脱,体积流量0.3 m L/min;定性、定量采用Q-... 目的建立UPLC-Q/TOF法同时定性、定量分析滇芹中主要化学成分。方法采用超高效液相色谱串联飞行时间质谱法进行分析,色谱柱为Agilent Poroshell 120 Hilic,流动相为乙腈-0.1%甲酸水溶液,梯度洗脱,体积流量0.3 m L/min;定性、定量采用Q-TOF正负离子全扫描+IDA(信息关联采集)模式。结果利用已建立的筛查数据库将满足质量误差小于5×10-6、同位素分布正确且含有二级碎片的离子作为分析目标化合物,结合软件Formula Finder、Mass Calculators等功能、在线数据库(Human Metabolome Database、Pub Chem、Chemical Book等)及二级碎片裂解规律,共鉴定出23个化合物,滇芹首次发现4个化合物。确定阿魏酸为定量分析指标性成分,其定量、定性离子分别为178和149;阿魏酸检测质量浓度线性范围为1.14~1 140 ng/m L(r=1.000),检测限、定量限分别为0.87、2.91 ng/m L,精密度、稳定性、重复性试验的RSD<2%,加样回收率为98.13%~101.25%(RSD=1.37%,n=5)。结论该方法灵敏度高、重现性好,分析快速、准确、可靠,可用于同时定性、定量检测滇芹药材中主要化学成分;云南滇芹中阿魏酸含量要高于西藏滇芹。 展开更多
关键词 滇芹 UPLC-Q/TOF 阿魏酸 6-(2-methoxyvinyl)-7-methyl-2H-1-benzopyran-2-one 1-O-β-D-glucopyranosyl-1 3-octanediol 2-pentylbutanedioic acid 4 4-dimethylcholesta-8(9) 14-dien-3β-ol
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西沙群岛来源真菌Pestalotiopsis sp.中脑苷脂类化合物及其生物活性研究 被引量:3
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作者 张琳 贾彦来 +1 位作者 房耀维 邵长伦 《中国海洋药物》 CAS CSCD 2017年第2期35-39,共5页
目的研究中国南海西沙群岛来源真菌Pestalotiopsis sp.ZJ-2009-7-6中的活性次级代谢产物的化学结构及其生物活性。方法利用现代波谱方法,鉴定脑苷脂类化合物cerebroside A(1)和(4E,8E)-N-D-2′-hydroxypalmitoyl-1-O-β-D-glycopyranosy... 目的研究中国南海西沙群岛来源真菌Pestalotiopsis sp.ZJ-2009-7-6中的活性次级代谢产物的化学结构及其生物活性。方法利用现代波谱方法,鉴定脑苷脂类化合物cerebroside A(1)和(4E,8E)-N-D-2′-hydroxypalmitoyl-1-O-β-D-glycopyranosyl-9-methyl-4,8-sphingadienine(2)的化学结构;利用抗菌和抗病毒活性模型对其进行生物活性评价。结果化合物1对痢疾志贺氏菌(Shigellad ysenteriae)显示一定的抗菌活性(MIC=50μmol/L);化合物2对单纯疱疹病毒(HSV-1)和肠道病毒71(EV71)有较好的抗病毒活性。结论从西沙群岛来源真菌Pestalotiopsis sp.7-6中分离获得2个具有抗菌和抗病毒活性的脑苷脂类化合物。 展开更多
关键词 CEREBROSIDE A (4E 8E)-N-D-2’-hydroxypalmitoyl-1-O-β-D-glycopyranosyl-9-methyl-4 8-sphingadienine 抗菌活性 抗病毒活性
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