应用制备高效液相色谱同时制备6种大豆异黄酮单体的方法研究

经大孔吸附树脂纯化大豆异黄酮粗提物后,以制备型高效液相色谱法(PHPLC)分离得到高纯度的大豆异黄酮单体。以SHIM-pack PRC-ODS(20 mm×250 mm,5 μm)制备柱,考察了流动相组成及流速、进样量对分离度的影响,确定了最佳色谱条件为乙腈-水流动相梯度洗脱,进样量800 μL,流速10 mL/min,在120 min内实现了6种异黄酮单体的基线分离及制备。经超高效液相色谱-串联质谱(UPLC-MS/MS)鉴定,6种异黄酮单体依次为大豆苷、黄豆黄苷、染料木苷、大豆素、黄豆黄素、染料木素。6种产品的纯度分别为95.54%、90.14%、100%、100%、96.27%、100%。方法具有简便易行、稳定性好、产品纯度高等特点,适用于大豆异黄酮标准品的制备。     

应用制备高效液相色谱同时制备6种大豆异黄酮单体的方法研究

经大孔吸附树脂纯化大豆异黄酮粗提物后,以制备型高效液相色谱法(PHPLC)分离得到高纯度的大豆异黄酮单体。以SHIM-pack PRC-ODS(20 mm×250 mm,5μm)制备柱,考察了流动相组成及流速、进样量对分离度的影响,确定了最佳色谱条件为乙腈-水流动相梯度洗脱,进样量800μL,流速10 mL/min,在120 min内实现了6种异黄酮单体的基线分离及制备。经超高效液相色谱-串联质谱(UPLC-MS/MS)鉴定,6种异黄酮单体依次为大豆苷、黄豆黄苷、染料木苷、大豆素、黄豆黄素、染料木素。6种产品的纯度分别为95.54%、90.14%、100%、100%、96.27%、100%。方法具有简便易行、稳定性好、产品纯度高等特点,适用于大豆异黄酮标准品的制备。     

高效液相色谱法分析大豆中磷脂酰胆碱的分子种

用高效液相色谱法（HPLC）在正相半制备硅胶柱上将大豆磷脂酰胆碱与其它组分分离，从柱后收集磷脂酰胆碱（PC），然后在反相C18柱上分析其分子种组成，蒸发光散射检测器检测。在25min内将大豆磷脂酰胆碱分离成11个分子种组分，使用易挥发溶剂，可获得各种分子种的纯物质，供进一步分析。分子种根据HPLC峰的脂肪酸组成分析而确定。     

反相高效液相色谱法制备纯化大豆异黄酮糖苷

利用制备高效液相色谱法从大豆总异黄酮提取物中制备出了3种大豆异黄酮糖苷。在Nova-Pak HR C18色谱柱(100 mm×25 mm i.d.,6 μm)上,以甲醇-体积分数为0.1%的乙酸水溶液(体积比为23∶77)为流动相,流速为20 mL/min,采用 等度洗脱方式,制备了3种大豆异黄酮糖苷,经质谱分析,确认它们分别为大豆苷、黄豆苷和染料木苷。高效液相色谱分析 表明,所制备的3种化合物的纯度均达到了99%以上。     

高效制备液相色谱法从荷叶中分离制备黄酮类化合物

采用高效制备液相色谱法从荷叶(Nelumbo nucifera Gaertn)中分离制备荷叶黄酮类化合物。用60%乙醇回流提取荷叶，粗提液浓缩后经D-101柱及聚酰胺柱色谱分离，再在Symmetry PrepTM C18柱上分离,以水-乙腈为流动相进行梯度洗脱（流速为5.0 mL/min）,得到了3种黄酮类化合物。经紫外光谱、红外光谱、核磁共振及质谱分析,确定该3种物质分别为金丝桃苷、异槲皮苷和紫云英苷。所制备的3种化合物的纯度都在97%以上,其中紫云英苷为首次从荷叶中分离得到。     

黄芪中黄酮类化合物的超临界流体色谱分离方法研究

考察了超临界流体色谱（SFC）中的色谱柱、改性剂、添加剂、流速、柱温和背压等因素对9种黄酮类成分（包括芒柄花素、异鼠李素、毛蕊异黄酮、山奈酚、槲皮素、紫云英苷、芒柄花苷、异槲皮苷、毛蕊异黄酮葡萄糖苷）分离的影响,与高效液相色谱法（HPLC）进行了比较,并建立了黄芪饮片中5种主要黄酮类化合物的SFC分析方法。采用Agilent ZORBAX RX－SIL色谱柱（4.6 mm × 150 mm,5 μm）进行分离,CO2－0.1%磷酸甲醇溶液为流动相梯度洗脱,流速为3 mL/min;柱温为35 ℃;背压为10 MPa,9种黄酮类化合物可在10 min内实现基线分离。5种黄酮类化合物在一定质量浓度范围内均具有良好的线性关系（r2 ≥ 0.963 2）,检出限为10.69 ~ 16.21 μg/mL,日内相对标准偏差（RSD）为1.3% ~ 2.0%;日间RSD为1.6% ~ 2.2%。5种黄酮类化合物在48 h内具有良好的稳定性,重复性为3.6% ~ 6.0%,回收率为91.8% ~ 112%。与HPLC法相比,9种化合物的保留时间顺序基本相反,SFC法更快速、经济环保,且其保留及选择性受色谱柱、改性剂和添加剂的影响较大,添加剂对色谱峰形影响明显。     

高效液相色谱法测定保健食品中的大豆异黄酮

建立了一种测定保健食品中大豆异黄酮的高效液相色谱分析方法,该方法可以使常见的大豆异黄酮6种主要成分大豆甙、黄豆甙、染料木甙、大豆甙元、黄豆黄素、染料木素得以分离和检测。采用乙腈-磷酸水溶液(pH2.8)作流动相,梯度洗脱,Venusil MP-C18色谱柱(150 mm×4.6 mmi.d.,5μm),流速为1.0 mL/min,紫外检测器,检测波长254 nm。结果表明各组分线性关系良好,相关系数R2为0.9991~0.9998,加标回收率在87%~106.9%,相对标准偏差均小于2%。检出限0.25~0.48μg/mL,该方法可同时测定大豆异黄酮的6种成分。     

高速逆流色谱分离制备陈皮中的黄酮类化合物

应用高速逆流色谱法分离制备了陈皮中3种黄酮类化合物。以石油醚-乙酸乙酯-甲醇-水(体积比为2∶4∶3∶3)为两相溶剂系统,在主机转速850 r/min、流动相流速1.7 mL/min、检测波长280 nm条件下进行分离制备,6 h内从4.0 g陈皮粗提物中一步分离制备得到橙皮苷10.1 mg、桔皮素49.8 mg和5-羟基-6,7,8,3′,4′-五甲氧基黄酮50.6 mg,纯度均达97.0%以上,各化合物结构经质谱和核磁共振氢谱、碳谱鉴定。利用该方法可以对陈皮中的黄酮类化合物进行快速的分离和纯化。     

静态瞬稳注射-化学发光法测定大豆异黄酮

大豆黄酮属于大豆异黄酮的一种,大豆异黄酮是大豆生长过程中形成的次生代谢产物,属于黄酮类化合物,主要以异黄酮糖苷和相应的苷元形式存在。大豆异黄酮具有弱雌激素、抗氧化、抗溶血和抗真菌等活性,能有效地预防和抑制白血病、骨质疏松、胃癌、乳腺癌和前列腺癌等多种疾病的发生。目前,测定大豆异黄酮的方法主要有紫外分光光度法、高效液相色谱法。因大豆异黄酮与杂蛋白的紫外吸收峰较近,用紫外分光光度法测定时背     

硅胶柱色谱结合高速逆流色谱法分离纯化荷花中黄酮类化合物

采用硅胶柱色谱结合高速逆流色谱法分离纯化了荷花中3种黄酮类化合物。荷花粗提物先经过硅胶柱色谱初步分离,得到黄酮含量高的组分,再经过高速逆流色谱分离,以乙酸乙酯-乙醇-水-乙酸(4:1:5:0.025, v/v/v/v)为两相溶剂系统,上相为固定相,下相为流动相,在主机转速800 r/min、流速2.0 mL/min、检测波长254 nm条件下,从150 mg样品中一次性分离制备得到6.1 mg槲皮素-3-O-β-D-葡萄糖醛酸苷(I), 14.8 mg杨梅素-3-O-β-D-葡萄糖苷(II)和20.2 mg紫云英苷(III),经高效液相色谱检测其纯度分别为97.0%、95.4%、96.3%,并通过质谱和核磁共振氢谱、碳谱鉴定各化合物的结构。该方法简便、快速、节省溶剂,可以对荷花中的黄酮类化合物进行快速有效的分离纯化,具有较好的实用价值,为荷花资源的进一步开发应用提供了参考依据。     

Furyl- and thienyl-silatranes and germatranes

We review our research on the synthesis and study of the physical and biological properties of furyl- and thienylgermatranes and -silatranes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 725–732, June, 1992.     

Review and patents and literature

The use of the insect cell/baculovirus expression system for producing recombinant proteins of bacterial, plant, insect, and mammalian origin has become widespread. The popularity of this eukaryotic expression system is due to many factors, including (1) potentially high protein expression levels, (2) ease and speed of genetic engineering, (3) ability to accommodate large DNA inserts, (4) protein processing similar to higher eukaryotic cells (e.g., mammalian cells), and (5) ease of insect cell growth (e.g., suspension growth). The following review of the literature discusses two engineering aspects of recombinant protein synthesis by insect cell cultures: bioreactor scale-up and insect cell line selection. Following this review patent abstracts and additional literature pertaining to expression of recombinant proteins in insect cell culture are listed.     

Ground- and excited-state aromaticity and antiaromaticity in benzene and cyclobutadiene

The aromaticity and antiaromaticity of the ground state (S 0), lowest triplet state (T 1), and first singlet excited state (S 1) of benzene, and the ground states (S 0), lowest triplet states (T 1), and the first and second singlet excited states (S 1 and S 2) of square and rectangular cyclobutadiene are assessed using various magnetic criteria including nucleus-independent chemical shifts (NICS), proton shieldings, and magnetic susceptibilities calculated using complete-active-space self-consistent field (CASSCF) wave functions constructed from gauge-including atomic orbitals (GIAOs). These magnetic criteria strongly suggest that, in contrast to the well-known aromaticity of the S 0 state of benzene, the T 1 and S 1 states of this molecule are antiaromatic. In square cyclobutadiene, which is shown to be considerably more antiaromatic than rectangular cyclobutadiene, the magnetic properties of the T 1 and S 1 states allow these to be classified as aromatic. According to the computed magnetic criteria, the T 1 state of rectangular cyclobutadiene is still aromatic, but the S 1 state is antiaromatic, just as the S 2 state of square cyclobutadiene; the S 2 state of rectangular cyclobutadiene is nonaromatic. The results demonstrate that the well-known "triplet aromaticity" of cyclic conjugated hydrocarbons represents a particular case of a broader concept of excited-state aromaticity and antiaromaticity. It is shown that while electronic excitation may lead to increased nuclear shieldings in certain low-lying electronic states, in general its main effect can be expected to be nuclear deshielding, which can be substantial for heavier nuclei.     

Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg^?1, the maximum residue level of European Union for quizalofop-p-ethyl).     

Syntheses and structures of P-anilino-P-chalcogeno- and P-anilino-P-iminodiazasilaphosphetidines and their group 12 and 13 metal compounds

The P-anilino-P-chalcogeno(imino)diazasilaphosphetidines [Me(2)Si(mu-N(t)Bu)(2)P=E(NHPh)] (E = O (3), S (4), Se (5), N-p-tolyl (6)) were synthesized by oxidizing the P-anilinodiazasilaphosphetidine [Me(2)Si(N(t)Bu)(2)P(NHPh)] (2) with cumene hydroperoxide, sulfur, selenium, and p-tolyl azide, respectively. The lithium salt of 4 reacted with thallium monochloride to produce ([Me(2)Si(mu-N(t)Bu)(2)P=S(NPh)-kappaN-kappaS]Tl)(7), which features a two-coordinate thallium atom. Treatment of 4-6 with AlMe(3) gave the monoligand dimethylaluminum complexes ([Me(2)Si(mu-N(t)Bu)(2)P=E(NPh)-kappaN-kappaE]AlMe(2)) (E = S (8), Se (9), N-p-tolyl (10)), respectively. In these complexes the aluminum atom is tetrahedrally coordinated by one chelating ligand and two methyl groups, as a single-crystal X-ray analysis of 8 showed. A 2 equiv amount of 4-6 reacted with diethylzinc to produce the homoleptic diligand complexes ([Me(2)Si(mu-N(t)Bu)(2)P=E(NPh)-kappaN-kappaE](2)Zn)(E = S (11), Se (12), N-p-tolyl (13)). A crystal-structure analysis of 11 revealed a linear tetraspirocycle with a tetrahedrally coordinated, central zinc atom.     

多环芳二酐型聚酯亚胺膜的透气性能

多环芳二酐型聚酯亚胺膜的透气性能李悦生，丁孟贤，徐纪平（浙江大学高分子科学与工程研究所，杭州，３１００２７）（中国科学院长春应用化学研究所）关键词聚醚酰亚胺，聚酯酰亚胺，膜，透气性通常的聚酰亚胺加工性能较差，在芳环二酐的苯环间引入醚键等柔性基团后，其...