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A New Flavan-3-ol Glucoside from Daphniphyllum oldhami 被引量:3
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作者 Zhi Yu SHAO, Da Yuan ZHU, Yue Wei GUOState Key Laboratory of Drug Research, Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第9期926-929,共4页
A new flavan-3-ol glucoside, (-)-afzelechin-7-O-β-D-glucopyranoside (1), has been isolated from the stem of Daphniphyllum oldhami. The structure of the new compound was elucidated on the basis of detailed spectroscop... A new flavan-3-ol glucoside, (-)-afzelechin-7-O-β-D-glucopyranoside (1), has been isolated from the stem of Daphniphyllum oldhami. The structure of the new compound was elucidated on the basis of detailed spectroscopie analysis and comparison with related compounds. 展开更多
关键词 Daphniphyllum oldhami flavan-3-ol (-)-afzelechin-7-O-β-D-glucopyranoside.
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Influence of Location of Production, Season and Genotype on Caffeine and Flavan-3-ols in Young Green Tea (Camellia sinensis) Leaves in Kenya 被引量:1
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作者 Bowa O. Kwachl Philip O. Owuor +2 位作者 David M. Kamau John K. Wanyoko Samson M. Kamunya 《Journal of Agricultural Science and Technology(B)》 2013年第8期557-574,共18页
Although tea is grown in agro-ecological regions widely varying in environmental factors affecting yield and quality, planters usually import genetic materials across the different growing regions assuming genotypes w... Although tea is grown in agro-ecological regions widely varying in environmental factors affecting yield and quality, planters usually import genetic materials across the different growing regions assuming genotypes with good quality attributes in one location maintain their status in all regions. However, tea quality has not been replicated in new production regions. Black tea quality is influenced by the green leaf quality precursors including caffeine, total polyphenols and individual flavan-3-ols which are precursors of theaflavins and thearubigins, key plain black tea quality parameters. Factors influencing levels of the precursors compounds have not been quantified for popular Kenyan tea cultivars. The influence of geographical production location and seasons on levels and ratios of the quality precursors for 10 black tea popular clones grown in three locations in Kenya under uniform agronomic inputs were monitored. Caffeine varied significantly (P _〈 0.05) with clones and location but not with season. The flavan-3-ols and their ratios all varied (P 〈 0.05) with clones and site but not with season, with significant interactions (P 〈 0.05) between locations and clones, and locations and seasons. These results explain the observed variations in plain black tea quality due to clones and location of production. Thus, farmers in different locations are unlikely to produce black tea of same quality. It is therefore necessary to evaluate new tea genotypes in intended growing areas to establish cultivars suitable for producing high quality plain black teas in the locations. Seasonal variations in plain black tea in Kenya are unlikely to vary significantly due to flavan-3-ols. 展开更多
关键词 Camellia sinensis flavan-3-ols location of production CLONES seasons.
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Excess Molar Volume and Apparent Molar Volume of Binary Mixtures of 2-Methyl-3-buten-2-ol with 1-Alcohol at 298.15K
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作者 刘迪霞 李浩然 +1 位作者 邓东顺 韩世钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第4期454-458,共5页
Excess molar volumes (V^E_m) of binary mixtures of2-methyl-3-buten-3-ol [CH_3C(OH)(CH_3)CHCG_2] with four 1-alcohols:methanol, ethanol, 1-propanol and l-butanol at 298.15 K andatmospheric pressure are derived from den... Excess molar volumes (V^E_m) of binary mixtures of2-methyl-3-buten-3-ol [CH_3C(OH)(CH_3)CHCG_2] with four 1-alcohols:methanol, ethanol, 1-propanol and l-butanol at 298.15 K andatmospheric pressure are derived from density measurements with avibrating-tube densimeter. All the excess volumes are negative in thesystems over the entire composition range. The results are correlatedwith the Redlich-Kister equation. The effects of chain length ofl-alcohols on V^E_m are discussed. The apparent molar volumes of2-methyl-3-ol and l-alcohols are calculated respectively. 展开更多
关键词 excess molar volume binary mixture 2-methyl-3-buten-2-ol l-alcohol
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Combination of low-concentration of novel phytoestrogen(8,9)-furanyl-pterocarpan-3-ol from Pachyrhizus erosus attenuated tamoxifen-associated growth inhibition on breast cancer T47D cells
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作者 Arief Nurrochmad Endang Lukitaningsih +2 位作者 Ameilinda Monikawati Dita Brenna Septhea Edy Meiyanto 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第11期847-852,共6页
Objective:To investigate the estrogenic effect of(8,9)-furanyl-pterocarpan-3-ol(FPC)on growth of human breast cancer T47D cells and the interactions between the FPC and tamoxifen(TAM),on the growth of estrogen recepto... Objective:To investigate the estrogenic effect of(8,9)-furanyl-pterocarpan-3-ol(FPC)on growth of human breast cancer T47D cells and the interactions between the FPC and tamoxifen(TAM),on the growth of estrogen receptor-dependent breast cancer T47D cells.Methods:The proliferation effect of FPC were conducted on T47D cells in vitro by MTT test.T47D cells were treated with FPC alone(0.01-200μmol/L)or in combination with TAM 20 nmol/L.Furthermore,the expression of ERαor c-Myc were also determined by immunohistochemistry.Results:The results indicated that administration of an anti-estrogen TAM showed growth inhibitory effect on T47D cells,wheraes co-administered with low concentration(less than 1μmol/L)of FPC attenuated to promote cell proliferation.In contrast,the combination of TAM with higher doses(more than 20μmol/L)of FPC showed growth inhibitory.This result was supported by immunocytochemistry studies that the administration of 20 nmol/L TAM down-regulated ER-αand c-Myc,but the combination of 20 nmol/L TAM and 1μmol/L FPC robustly up-regulated expression of ER-α.Thus,the reduced growth inhibition of TAM 20 nmol/L by FPC 1μmol/L on T47D cells may act via the modulation of ER-α.Conclusions:The findings indicate and suggest that FPC had estrogenic activity at low concentrations and anti-estrogenic effect that are likely to be regulated by c-Myc and estrogen receptors.We also confirm that low concentration of FPC attenuated the growth-inhibitory effects of TAM on mammary tumor prevention.Therefore,the present study suggests that caution is warranted regarding the consumption of dietary FPC by breast cancer patients while on TMA therapy. 展开更多
关键词 PHYTOESTROGEN (8 9)-furanyl-pterocarpan-3-ol Tamoxifen Estrogenic effect T47D CELLS
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Asymmetric synthesis of 3β-acetoxy-17,17-ethylendioxy-15β,16β-methylene-5-androsten-7β-ol
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作者 刘丰良 周康根 +1 位作者 阳卫军 杨喜云 《Journal of Central South University of Technology》 EI 2004年第1期59-62,共4页
acetoxy-17,17-ethylendioxy-15β,16β-methylene-5-androsten-7β-ol(Ⅰ) was prepared by 3 steps from 3β-acetoxy-15β,16β-methylene-5-androsten-17-one (Ⅱ) with overall yield of 52.7%. Thus, interaction of ethylene... acetoxy-17,17-ethylendioxy-15β,16β-methylene-5-androsten-7β-ol(Ⅰ) was prepared by 3 steps from 3β-acetoxy-15β,16β-methylene-5-androsten-17-one (Ⅱ) with overall yield of 52.7%. Thus, interaction of ethylene glycol and material (Ⅱ) gave 3β-acetoxy- 17,17-ethylendioxy-15β,16β-methylene-5-androsten (Ⅲ) which was subsequently oxidated and stereoselectively reduced to produce compound(Ⅰ). The normal influencing factors, such as the types of oxidants and reductives, the mole ratio of reactants, the reaction temperature, and the addition ways of reactants, in oxidation and reduction were discussed. The results show that the oxidation rate order is CrO3-C5H5N (1∶1, mole fraction)>CrO3-C5H5N(1∶2)>(C5H5NH)2Cr2O7 in terms of the oxidant, the yield of the oxidation becomes higher with increasing the oxidant stoichiometry and raising the reaction temperature. And the optimum condition is that the reaction temperature is at 30 ℃, and n (Ⅲ)/ n (CrO3-C5H5N(1∶2))=1∶20. The yield of the -7β alcohol order with Li[Al(OC(CH3)3)3H] (e.g.78.6%) is more than that with NaBH4 (e.g.14.5%) in terms of the reductive (agent) and the reduction rate decreases in the course of reaction. The compound (Ⅰ) is characterized by IR and MS. 展开更多
关键词 acetoxy-15β 16β-methylene-5-androsten-17-one asymmetric synthesis 3β-acetoxy-17 17- ethylendioxy-15β 16β-methylene-5-androsten-7β-ol
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胆甾烷-3-醇及胆甾烷-3-酮的合成研究进展
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作者 刘强 龙可栋 +2 位作者 李兴 常宏宏 魏文珑 《广州化工》 CAS 2011年第7期25-27,共3页
甾族化合物在生物、医药等诸多方面具有很重要的利用价值。本文在大量文献的基础上对以胆固醇为原料,经还原反应制备胆甾烷-3-醇和以胆甾烷-3-醇为原料经氧化反应制备胆甾烷-3-酮的合成工艺进行了综述,重点对上述合成工艺的催化剂及催... 甾族化合物在生物、医药等诸多方面具有很重要的利用价值。本文在大量文献的基础上对以胆固醇为原料,经还原反应制备胆甾烷-3-醇和以胆甾烷-3-醇为原料经氧化反应制备胆甾烷-3-酮的合成工艺进行了综述,重点对上述合成工艺的催化剂及催化方法进行了阐述,并分析了不同催化剂的优缺点,对今后的研究方向进行了归纳。 展开更多
关键词 甾族化合物 胆固醇 胆甾烷-3-醇 胆甾烷-3-酮
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由胆甾醇制备2-苯亚甲基-5α-胆甾烷-3-酮
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作者 彭文宇 袁江纯 +2 位作者 李筱芳 易平贵 陶洪文 《精细化工中间体》 CAS 2019年第6期23-26,53,共5页
以胆甾醇(■)为起始原料,通过10%Pd-C催化加氢还原合成5α-胆甾烷-3β-醇(■),■经Jones试剂氧化反应,得到5α-胆甾烷-3-酮(■),■经NaOH催化与苯甲醛发生Claisen-Schmidt缩合生成2-苯亚甲基-5α-胆甾烷-3-酮(■)。对制备工艺进行了优化... 以胆甾醇(■)为起始原料,通过10%Pd-C催化加氢还原合成5α-胆甾烷-3β-醇(■),■经Jones试剂氧化反应,得到5α-胆甾烷-3-酮(■),■经NaOH催化与苯甲醛发生Claisen-Schmidt缩合生成2-苯亚甲基-5α-胆甾烷-3-酮(■)。对制备工艺进行了优化,确定加氢反应的条件为:乙醇溶液中,25℃反应20 h;Jones试剂氧化反应的条件为:丙酮溶液中30℃反应2 h;Claisen-Schmidt缩合反应的条件为:乙醇溶液中,在NaOH催化下先25℃反应2 h,再升温至50℃反应3 h。优化条件下,3步反应总收率74.7%。产物结构经1H NMR、13C NMR和APCI-MS确证。 展开更多
关键词 5α-胆甾烷-3β-醇 5α-胆甾烷-3-酮 2-苯亚甲基-5α-胆甾烷-3-酮 Jones试剂 Claisen-Schmidt缩合
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(+)—Selina—3,11—dien—9—01的不对称全合成
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作者 杨炯 熊照明 《合成化学》 CAS CSCD 1997年第A10期496-496,共1页
关键词 (+)-Selina-3 11-dien-9-ol 桉烷 不对称合成
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川黄柏中原小檗碱型生物碱及其细胞毒性研究 被引量:7
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作者 闫玉鑫 杨颖 +1 位作者 池利昆 郑萍 《云南师范大学学报(自然科学版)》 2022年第1期46-49,共4页
采用甲醇溶剂对芸香科黄柏属川黄柏的茎进行回流提取,利用硅胶、胺基硅胶和葡聚糖凝胶等多种柱色谱法对提取物化学成分进行研究,通过核磁共振和电喷雾质谱等波谱技术以及与文献报道数据比对,从中分离鉴定了4个原小檗碱型生物碱,分别鉴... 采用甲醇溶剂对芸香科黄柏属川黄柏的茎进行回流提取,利用硅胶、胺基硅胶和葡聚糖凝胶等多种柱色谱法对提取物化学成分进行研究,通过核磁共振和电喷雾质谱等波谱技术以及与文献报道数据比对,从中分离鉴定了4个原小檗碱型生物碱,分别鉴定为二氢小檗碱(1),hediamine(2),2-methoxy-berbin-10-ol(3),3-methoxy-berbin-10-ol(4).并对化合物1的波谱进行详细归属,对化合物2进行单晶衍射实验,确定其绝对构型.所有化合物均对人肝癌细胞(HepG2)有较强的细胞毒性. 展开更多
关键词 黄柏 小檗碱 二氢小檗碱 hediamine 2-methoxy-berbin-10-ol 3-methoxy-berbin-10-ol
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彭泽贝母中二萜类成分 被引量:2
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作者 刘红宁 李飞 +3 位作者 罗永明 朱卫丰 颜冬梅 黄兴发 《药学学报》 CAS CSCD 北大核心 2007年第11期1152-1154,共3页
为了研究彭泽贝母的化学成分。利用多种柱色谱方法进行分离纯化,根据光谱数据和理化性质进行结构鉴定。共分离并鉴定了6个对映-贝壳杉类二萜化合物:ent-kauran-15-en-17-ol(I),ent-kauran-15-en-3α,17-diol(II),鄂贝新醇(III),ent-kaur... 为了研究彭泽贝母的化学成分。利用多种柱色谱方法进行分离纯化,根据光谱数据和理化性质进行结构鉴定。共分离并鉴定了6个对映-贝壳杉类二萜化合物:ent-kauran-15-en-17-ol(I),ent-kauran-15-en-3α,17-diol(II),鄂贝新醇(III),ent-kauran-16α,17-diol(IV),ent-kauran-3α,16α,17-triol(V),ent-16,17-epoxy-kauran-3α-ol(VI)。6个化合物均为首次从彭泽贝母中分得,其中ent-16,17-epoxy-kauran-3α-ol(VI)为新化合物。 展开更多
关键词 彭泽贝母 化学成分 ent-16 17-epoxy-kauran-3α-ol
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冬虫夏草定殖菌Aspergillus fumigatus中一个新的聚酮类化合物 被引量:1
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作者 李莎 李小华 +5 位作者 邱玲 旷歧轩 文新 于思 郭大乐 邓赟 《天然产物研究与开发》 CAS CSCD 北大核心 2018年第4期588-590,共3页
从冬虫夏草中分离得到一株定殖菌烟曲霉,对其发酵液的乙酸乙酯萃取部位进行化学成分研究,借助正反相硅胶柱色谱及HPLC等方法进行分离纯化,分离得到一个聚酮类新化合物1,利用多种波谱手段(HRESI-MS,1D NMR,2D NMR)确定其结构为为6-methox... 从冬虫夏草中分离得到一株定殖菌烟曲霉,对其发酵液的乙酸乙酯萃取部位进行化学成分研究,借助正反相硅胶柱色谱及HPLC等方法进行分离纯化,分离得到一个聚酮类新化合物1,利用多种波谱手段(HRESI-MS,1D NMR,2D NMR)确定其结构为为6-methoxy-3-methyl-1H-isochromen-8-ol。化合物1对H1299(人肺癌细胞)、H460(大细胞肺癌细胞)、HGC-27(人胃癌细胞)、A549(人非小细胞肺癌细胞)和mnk-43(人胃癌高分化细胞)五种细胞株均有弱的细胞毒活性。 展开更多
关键词 烟曲霉 冬虫夏草 6-methoxy-3-methyl-1H-isochromen-8-ol 结构鉴定 细胞毒活性
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西洋参茎叶总皂苷氧化裂解产物中的新侧链环合型达玛烷型三萜 被引量:2
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作者 黄媛 李宁 +2 位作者 李铣 高璐莎 孟大利 《药学学报》 CAS CSCD 北大核心 2008年第3期277-280,共4页
为了研究西洋参茎叶总皂苷氧化碱解产物的组成,对加拿大产西洋参茎叶总皂苷进行氧化碱解后,其产物通过硅胶柱色谱、Sephadex LH-20柱色谱、重结晶等方法进行分离纯化得到2个化合物。根据化合物的理化性质和光谱数据,鉴定其结构为:(12R,2... 为了研究西洋参茎叶总皂苷氧化碱解产物的组成,对加拿大产西洋参茎叶总皂苷进行氧化碱解后,其产物通过硅胶柱色谱、Sephadex LH-20柱色谱、重结晶等方法进行分离纯化得到2个化合物。根据化合物的理化性质和光谱数据,鉴定其结构为:(12R,20S,24R)-20,24;12,24-diepoxy-24-deisopropyl-dammarane-3β-ol(1)和(20S,24R)-20,24-epoxydammarane-3β,12β,25-triol(2)。化合物1,2均为首次从西洋参茎叶总皂苷碱解产物中分离得到侧链环合的达玛烷型三萜,其中化合物1为新化合物。 展开更多
关键词 西洋参茎叶总皂苷 氧化碱解 (12R 20S 24R)-20 24 12 24-diepoxy-24-deisopropyl-dammarane-3β-ol
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甜草Oldenlandia cantonensis How的化学成分 被引量:1
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作者 蓝文健 李厚金 《应用化学》 CAS CSCD 北大核心 2006年第8期871-874,共4页
研究了民间草药甜草O ldenlandia cantonensisHow的化学成分。从乙醇提取物的乙酸乙酯洗脱部分得到新的五环三萜urs-12-en-29-αoic ac id-3β-ol。该化合物结构通过NMR、IR、MS等波谱数据综合解析确定。研究了urs-12-en-29-αoic ac i... 研究了民间草药甜草O ldenlandia cantonensisHow的化学成分。从乙醇提取物的乙酸乙酯洗脱部分得到新的五环三萜urs-12-en-29-αoic ac id-3β-ol。该化合物结构通过NMR、IR、MS等波谱数据综合解析确定。研究了urs-12-en-29-αoic ac id-3β-ol对重组人DNA拓扑异构酶Ⅰ、肝癌细胞BEL-7402和胃腺癌细胞MCG-803的抑制作用,效果显著,IC50值分别为12.0×10-6、6.5×10-6、8.0×10-6g/mL。由V(石油醚)∶V(乙酸乙酯)=20∶1洗脱得到的低极性成分进行了气相色谱-质谱分析,共鉴定60个化合物,其中长链脂肪族化合物,如烷烃、饱和及不饱和羧酸(酯)含量较丰富,占36.16%,萜类和甾体类化合物分别占6.42%和9.28%。 展开更多
关键词 Oldenlandia cantonensis HOW 化学成分 urs-en-29α-oic acid-3β-ol 生理活性
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产印楝素前体tirucalla-7,24-dien-3β-ol的酿酒酵母细胞工厂构建 被引量:3
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作者 刘佳柔 苏新堯 +1 位作者 刘金龙 王彩霞 《中国中药杂志》 CAS CSCD 北大核心 2021年第19期4959-4968,共10页
印楝素是从印楝属植物印楝种子中提取的一种高度氧化的柠檬苦素类三萜化合物,是公认无害的植物源杀虫剂。在植物中含量很低,化学合成步骤繁琐,通过生物合成的方式来获取印楝素将对印楝素的商业用途提供很大的帮助,但生物合成途径未知限... 印楝素是从印楝属植物印楝种子中提取的一种高度氧化的柠檬苦素类三萜化合物,是公认无害的植物源杀虫剂。在植物中含量很低,化学合成步骤繁琐,通过生物合成的方式来获取印楝素将对印楝素的商业用途提供很大的帮助,但生物合成途径未知限制了利用合成生物学进行外源合成。该研究在实验室优化过的甲羟戊酸途径(MVA)的代谢流的酿酒酵母菌株中,通过异源表达来自苦楝和印楝中的氧化鲨烯环化酶(OSCs)AiOSC1和MaOSC1基因,验证了上述2个OSC为苦楝素和印楝素合成的三萜骨架化合物。进一步将印楝氧化鲨烯环化酶基因(AiOSC1),连同拟南芥来源鲨烯合酶基因(AtAQS2),以及酿酒酵母来源截短的3-羟基-3-甲基戊二酰单酰辅酶A还原酶基因(PgtHMGR)共同整合到酿酒酵母染色体的delta位点上,构建了高产印楝素合成起始三萜骨架tirucalla-7,24-dien-3β-ol的酵母菌株。进一步将苦楝来源的细胞色素氧化酶基因(MaCYP71BQ5)导入上述高产tirucalla-7,24-dien-3β-ol酵母细胞中,成功在酵母细胞中检测到MaCYP71BQ5的产物。该研究不仅为tirucalla-7,24-dien-3β-ol生物合成奠定了基础,也为后期在酵母中研究印楝素生物合成途径中的细胞色素氧化酶(CYP450)提供了优势底盘菌株。 展开更多
关键词 氧化鲨烯环化酶 tirucalla-7 24-dien-3β-ol 酿酒酵母
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A Novel Phenylpropanoid-substituted Catechin Glycoside and a New Dihydrochalcone from Sarcandra glabra 被引量:12
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作者 Yuan LI Dong Ming ZHANG +2 位作者 Shi Shah YU Jian Bei LI Yong Ming LUO 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第2期207-210,共4页
A novel phenylpropanoid-substituted catechin glycoside glabraoside A 1 and a new dihydrochalcone 3'-(7"-allylphenyl)-2',4',4"-trihydroxy-6'-methoxydihydrochalcone 2 were isolated from the herbs of Sarcandra gl... A novel phenylpropanoid-substituted catechin glycoside glabraoside A 1 and a new dihydrochalcone 3'-(7"-allylphenyl)-2',4',4"-trihydroxy-6'-methoxydihydrochalcone 2 were isolated from the herbs of Sarcandra glabra. Their structures were elucidated on the basis of spectroscopic analyses and chiroptical methods. 展开更多
关键词 Sarcandra glabra glabraoside A phenylpropanoid-substituted flavan-3-ols dihydrochalcone.
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Intramolecular O-Sn coordination in (Z)-1-(triphenylstannyl)-3-phenyl-1-buten-3-ol: Evidence by X-ray diffracation analysis and bromination 被引量:3
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作者 FU, Fang-Xin FU, Yu-Jie ZHU, Dong-Sheng FANG, Qun-Xin PAN, Hua-DeChemistry Department, Northeast Normal University, Changchun, Jilin 130024, ChinaLIN, Yong-Hua JIN, Song-Chun Changchun Institute of Applied Chemistry Chinese Academy of Sciences, Changchun, Jilin 130022, China 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1994年第4期365-371,共7页
The synthesis and properties of (Z)-1-(triphenylstannyl)-3-phenyl-1-buten-3-ol (1) are described. Compound 1 crystallizes from alcohol in the monoclinic space group P21/c with unit-cell dimensions a=9.296(2), 6=14.081... The synthesis and properties of (Z)-1-(triphenylstannyl)-3-phenyl-1-buten-3-ol (1) are described. Compound 1 crystallizes from alcohol in the monoclinic space group P21/c with unit-cell dimensions a=9.296(2), 6=14.081(3), c=18.390(5) A,B=97.70(2), V=2385.5(1) A3, Z=4, F(000)=1008, Dc=1.38 g.cm-3,u=10.88 cm-1, final R=0.0359 for 3079 observed reflection [I > 3(I)]. The X-ray diffraction analysis of this compound shows the presence of an intramolecular coordination to the tin atom giving rise to a five-membered ring in which the metal exhibits a distroted trignoal bipyramidal geometry; as a consequence, a phenyl group, probably the apical one, is cleaved more easily by bromine than the vinyl substituent. 展开更多
关键词 Sythesis X-ray diffraction analysis (Z)-l-(triphenylstannyl)-3-phenyl-l-buten-3-ol.
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The Identification of Two New Sterols from Marine Organism 被引量:3
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作者 Shi Hai XU Long Mei ZENG(Department of Chemistry, Jinan University Guanzhou 510632)(Department of Chemistry Zhongshan University Guanzhou 510275) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第6期531-534,共4页
Two new sterol have been isolated from the South China Sea marine organism. Compound 1 was isolated from the sponge Polymastia sobustia and compound 2 was obtained from the soft coral Sinularia inexplicata. Their stru... Two new sterol have been isolated from the South China Sea marine organism. Compound 1 was isolated from the sponge Polymastia sobustia and compound 2 was obtained from the soft coral Sinularia inexplicata. Their structures were established as 3 beta-hydroxy-stigmast-5en-7-one and 24-methylene cholestan -3 beta, 6 beta, 9 alpha, 19-tetrol by variety of spectral analysis such as IR, EIMS, 1DNMR, H-1-H-1 COSY, HMQC, HMBC, NOESY. 展开更多
关键词 sterol Polymastia sobustia 3 beta-hydroxy- stigmast-5en-7-one soft coral Sinularia inexplicita 24-methylene cholestan-3 beta 6 beta 9 alpha 19-tetrol
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A new prenylated arylbenzofuran derivative from Morus alba L. 被引量:3
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作者 Tian, Hai Ying He, Xi +5 位作者 Zeng, Guang Yao Tan, Jian Bin Shuang, Fu Liu, Guo Ru Tan, Gui Shan Zhou, Ying Jun 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期329-331,共3页
2-[3,5-Di-O-β-D-glucosyl-4-(3-methylbut-2-enyl)phenyl]benzofuran-6-ol,a new prenylated arylbenzofuran derivative was isolated from Morus alba L.Its structure was elucidated by various spectroscopic methods including ... 2-[3,5-Di-O-β-D-glucosyl-4-(3-methylbut-2-enyl)phenyl]benzofuran-6-ol,a new prenylated arylbenzofuran derivative was isolated from Morus alba L.Its structure was elucidated by various spectroscopic methods including MS,~1H NMR,^(13)C NMR,DEPT,~1H-~1HCOSY,HMQC and HMBC. 展开更多
关键词 Morus alba L. Prenylated arylbenzofuran 2-[3 5-Di-O-β-D-glu-4-(3-methylbut-2-enyl)phenyl]benzofuran-6-ol
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Dietary flavonoid intake and risk of stomach and colorectal cancer 被引量:1
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作者 Hae Dong Woo Jeongseon Kim 《World Journal of Gastroenterology》 SCIE CAS 2013年第7期1011-1019,共9页
Stomach and colorectal cancers are common cancers and leading causes of cancer deaths.Because the alimentary tract can interact directly with dietary components,stomach and colorectal cancer may be closely related to ... Stomach and colorectal cancers are common cancers and leading causes of cancer deaths.Because the alimentary tract can interact directly with dietary components,stomach and colorectal cancer may be closely related to dietary intake.We systematically searched published literature written in English via PubMed by searching for terms related to stomach and colorectal cancer risk and dietary flavonoids up to June 30,2012.Twenty-three studies out of 209 identified articles were finally selected for the analysis.Log point effect estimates and the corresponding standard errors were calculated using covariate-adjusted point effect estimates and 95%CIs from the selected studies.Total dietary flavonoid intake was not associated with a reduced risk of colorectal or stomach cancer [odds ratio(OR)(95%CI) = 1.00(0.90-1.11) and 1.07(0.70-1.61),respectively].Among flavonoid subclasses,the intake of flavonols,flavan-3-ols,anthocyanidins,and proanthocyanidins showed a significant inverse association with colorectal cancer risk [OR(95%CI) = 0.71(0.63-0.81),0.88(0.79-0.97),0.68(0.56-0.82),and 0.72(0.61-0.85),respectively].A significant association was found only between flavonols and stomach cancer risk based on a limited number of selected studies [OR(95%CI) = 0.68(0.46-0.99)].In the summary estimates from casecontrol studies,all flavonoid subclasses except flavones and flavanones were inversely associated with colorectal cancer risk,whereas neither total flavonoids nor any subclasses of flavonoids were associated with colorectal cancer risk in the summary estimates based on the cohort studies.The significant association between flavonoid subclasses and cancer risk might be closely related to bias derived from the case-control design.There was no clear evidence that dietary flavonoids are associated with reduced risk of stomach and colorectal cancer. 展开更多
关键词 Flavonoids FLAVONOLS Flavones FLAVANONES Flavan-3-ols ANTHOCYANIDINS PROANTHOCYANIDINS Cancer RISK Meta-analysis
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Effect of (+)-limonene and 1-methoxy-2-propanol on Ips typographus response to pheromone blends 被引量:1
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作者 Miroslav Blazenec Rastislav Jakus 《Journal of Forestry Research》 SCIE EI CAS CSCD 2009年第1期37-44,共8页
We compared two different strategies to increase the catches oflps typographus (L.), particularly males, in pheromone-baited traps. The first of these strategies, the barrier approach, used alternating pheromone ble... We compared two different strategies to increase the catches oflps typographus (L.), particularly males, in pheromone-baited traps. The first of these strategies, the barrier approach, used alternating pheromone blends, targeting males and females respectively, in closely-spaced traps forming a barrier around forest stands. The second strategy, the single trap approach, used widely-spaced traps that were all baited with the same lure and intended to trap the highest possible numbers of males without compromising trapping of females. In the blend used for the barrier traps targeting primarily males, with a lower percentage of (4S)-cis-verbenol (cV), the (-)-α-pinene was replaced step wise with (+)-limonene at rates of 0%, 1%, 10%, 35%, 60% and 90%. This replacement had no significant effect on the numbers of responding 1. typographus males, but there was a slight effect on the percentage of males caught. In the attractant blend for the barrier traps targeting females, with a higher percentage of cV, the 2-methyl-3-buten-2-ol (MB) was replaced with 1-methoxy-2-propanol (MP) in a similar fashion as for the male-specific blends. The replacement did not significantly affect the catch of females. Thus, it is pos- sible to use the MP in the blend with cV and ipsdienol without significant change in catch efficacy. In the blends for single traps, the (-)-α- pinene was replaced with (+)-limonene and MB with MP. The replacement of (-)-α-pinene had only a slight effect on the percentage of males, but the results suggest that replacing MB with MP in the blend will not significantly reduce trapping efficacy. 展开更多
关键词 pheromone trap barrier single traps (4S)-cis-verbenol 2-methyl-3-buten-2-ol (-)-α-pinene
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