高效液相色谱法测定2种中药片剂中紫丁香苷的含量

建立了测定2种中药制剂灭澳灵片和活络消痛片中紫丁香苷含量的高效液相色谱方法.采用KromasilC18反相色谱柱(5μm,250 mm×4.6 mm),以乙腈-1%冰醋酸溶液(体积比10∶90)为流动相,流速1.0 mL/min,检测波长265 nm,在15 min内完成分离检测.紫丁香苷在0.16~100μg/mL范围内呈良好的线性关系(r=0.9999),最低检出限0.1μg/mL(S/N=3).灭澳灵片的加样回收率为92.2%~97.6%,活络消痛片的加样回收率为94.0%~102.6%.     

压敏胶贴片中芍药苷及残留溶剂含量的测定

建立了贴片中标示成分芍药苷含量的高效液相色谱(HPLC)法和贴片中各种残留溶剂含量的气相色谱(GC)法。样品经甲醇提取,离心分离后,以乙腈-水(含4%HAc)的体积比为16∶84作流动相,选择ODS-2HypersilC18(150×4.6mm,5μm)色谱柱,测定芍药苷含量。贴片基质经乙醚处理,离心分离,以GC内标法测定残留溶剂含量。结果表明:HPLC法的精密度、重现性和回收率良好;GC法测得乙酸乙酯、异丙醇、乙醇三种残留溶剂,贴片中残留溶剂总量为2.1×10-4,符合药典限度规定。     

大鼠血浆中芍药苷的UHPLC-MS/MS法测定及其药动学研究

建立了超高效液相色谱串联三重四极杆质谱(UHPLC-MS/MS)测定大鼠血浆中的芍药苷含量的分析方法,并用于芍药苷药动学研究。采用UHPLC-MS/MS电喷雾电离源(ESI),负离子模式,多反应监测(MRM)法定量分析芍药苷,离子对为m/z 479.1→m/z 121.0和m/z 479.1→m/z 327。计算芍药苷血浆质量浓度,采用PK Solutions 2.0软件计算药动学参数。大鼠血浆中芍药苷在0.01~2μg/mL范围内线性良好,定量限为0.01μg/mL。日内和日间RSD均11%,准确度均在±15%之间。低、中、高3个质量浓度下绝对回收率均70%。大鼠腹腔注射20 mg/kg芍药苷后的主要药动学参数c_(max)为(14.28±1.76)μg/mL,T_(1/2)E_(phase)为(176.11±23.47)min,AUC_(0-t)为(1193.30±213.70)ng·min/mL。     

高效液相色谱法测定壮骨祛风合剂中芍药苷

采用高效液相色谱法测定了壮骨祛风合剂中芍药苷的含量。色谱柱为VP-ODS;流动相为甲醇-水-冰乙酸,体积比为25∶75∶0.2,流速为1.0mL/min;检测波长为235nm。实验结果表明,芍药苷在0.2~2.0μg/mL范围内呈线性关系,线性回归方程为A=40378.02c-3310.02,相关系数r=0.9994,测定结果的相对标准偏差为0.63%,平均加标回收率为99.92%。该方法可作为壮骨祛风合剂的质量控制标准。     

固相萃取-高效液相色谱法测定中药制剂及保健食品中芍药苷

应用固相萃取-高效液相色谱法测定中药制剂及保健食品中芍药苷的含量。样品经30%(体积分数)乙醇溶液提取,酸性氧化铝固相萃取柱净化。以C18色谱柱为分离柱,用乙腈和0.1%(体积分数)磷酸溶液以不同比例混合的溶液为流动相进行梯度洗脱,在检测波长230nm处进行测定。芍药苷的质量浓度在2.00~200mg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)为0.5mg·L-1。加标回收率在99.5%~101%之间,测定值的相对标准偏差(n=6)在均小于2%。     

高效液相色谱法测定千金止带丸中芍药苷的含量

本文建立了高效液相色谱法(HPLC)测定千金止带丸中芍药苷含量的方法。采用Reliasil C18柱(150×4.6 mm i.d., 5μm),以乙腈水(12∶88,V/V)为流动相,在流速0.8 mL/min,检测波长230 nm,柱温40℃条件下,芍药苷在0.139 8~0.699 0μg范围内具有良好的线性关系,r =0.999 9,平均回收率为99. 09%, RSD = 0. 91%(n=5)。本法简便,准确,灵敏度高,重复性好,可用于该药品成分的含量测定。     

酶联免疫吸附法测定血浆中芍药苷浓度

建立了间接竞争酶联免疫吸附法测定血浆中芍药苷浓度.在10～200 μg/L浓度范围内,线性关系良好,线性回归方程为y=-0.1721 logC 1.9645,相关系数0.9927;回收率为89%～102%.运用本方法测定了大鼠一次灌胃后血浆中的芍药苷浓度.比较了分别给药芍药苷单体及中药复方四逆散提取物后,血浆中的芍药苷浓度.研究结果表明:四逆散配伍组方后,芍药苷的生物利用度较低.     

加压毛细管电色谱在芎菊上清片中栀子苷及黄芩苷分离检测中的应用

采用加压毛细管反相电色谱技术,建立了一种用于分离检测芎菊上清片中栀子苷和黄芩苷的高效简便新方法。色谱柱为EP-100-20/45-3 C18毛细管柱(总长度45 cm,有效长度20 cm,直径为100μm,ODS填料内径3μm),柱温为25℃,流动相采用20 mmol/L Na H2PO4-乙腈(71∶29),流动相的总流速为0.035m L/min,分离电压为+2.0 k V,检测波长为240 nm。经等度洗脱,栀子苷和黄芩苷可实现快速分离,峰面积的相对标准偏差(RSD)不大于2.8%,回收率为91.9%~101.2%,测得该芎菊上清片中栀子苷的含量为2.616 mg/g,黄芩苷的含量为11.220 mg/g。该方法的选择性好、柱效高、试剂用量少,用于芎菊上清片中黄芩苷和栀子苷的分离检测,结果满意。     

在线二维柱切换-超高效液相色谱法同时测定明目地黄丸中莫诺苷、马钱苷、芍药苷、丹皮酚的含量

建立了二维柱切换-超高效液相色谱法同时测定明目地黄丸中莫诺苷、马钱苷、芍药苷、丹皮酚含量的方法.一维色谱柱为Thermo Accucore XL C18(250mm×2.1 mm,4μm),二维色谱柱为DIONEX Acclaimphenyl-1(150mm ×4.6mm,3μm),一维分析流动相为乙腈-水,梯度洗脱,二维分析流动相为乙腈-水,等度洗脱,14.5 min进行阀切换;检测波长:0～14.5 min为240 nm,14.5～ 30 min为275 nm,流速:0.5 mL/min,柱温:30℃.30 min即可完成明目地黄丸中莫诺苷、马钱苷、芍药苷、丹皮酚的含量测定,并有效地将莫诺苷同分异构体分离.莫诺苷、马钱苷、芍药苷、丹皮酚的线性范围分别为7.6 ～ 377 mg/L,9.2～ 459 mg/L,8.4～419 mg,/L和8.2 ～ 409 mg/L,相关系数为0.9999,加样回收率为98.3％～ 100.2％.本方法快捷高效,可对控制明目地黄丸质量提供参考.     

固相萃取-高效液相色谱-电喷雾串联质谱法分析芍药和酒芍药的水溶性化学成分

利用固相萃取-高效液相色谱-电喷雾串联质谱法(SPE-HPLC-DAD-ESI-MS2)分析了芍药(Paeonia lactiflora Pall.)及其炮制品酒芍药(Paeonia lactiflora Pall.preparated with wine)水煎液中化学成分的种类和结构,并对其主要有效成分芍药苷进行了定量测定.用此方法得到了芍药和酒芍药水煎液的紫外色谱(UV)图、总离子流色谱(TIC)图和萃取离子色谱(EIC)图,以及相应色谱峰的紫外光谱图和EIC/MS2的质谱图.对其进行解析,发现芍药和酒芍药水煎液中所含化学成分基本一致,但酒芍药水煎液中除主要活性成分芍药苷含量基本未变外,其它酚酸性化学成分含量相对于芍药水煎液均有不同程度的下降.同时鉴别出芍药和酒芍药水煎液中共同含有的16种成分,它们分别是:蔗糖、(+)-儿茶素、Mudanpioside E、芍药新苷、芍药内酯苷、氧化芍药苷、芍药苷、羟基芍药苷、没食子酰芍药苷*、牡丹皮苷Ⅰ、苯甲酰芍药苷、三没食子酰葡萄糖、四没食子酰葡萄糖、五没食子酰葡萄糖.以上分析说明,酒炙可保留芍药的药效,同时"缓和其酸寒伐肝之性".     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.     

Synthesis of N-substituted carbazolones from α-iodo enaminones via Pd(0)-catalyzed intramolecular coupling under microwave irradiation

A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd₂(dba)₃-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.     

Synthesis of substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles by intramolecular nitrilimine cycloaddition

Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.     

Catalyst free,visible-light promoted photoaddition reactions between C60 and N-trimethylsilylmethyl-substituted tertiary amines for synthesis of aminomethyl-1,2-dihydrofullerenes

An efficient and benign method for the preparation of aminomethyl-substituted fullerenes has been developed. The process, involving catalyst free, visible-light irradiation of 10% EtOH-toluene solutions containing fullerene C₆₀ and N-trimethylsilylmethyl-substituted amines by using a 20 W compact fluorescent lamp, leads to formation of aminomethyl-substituted fullerene adducts in a highly efficient manner. The photoaddition reaction takes place via a pathway initiated by visible light absorption by C₆₀, followed by SET from the amine to the triplet excited state of C₆₀. Ethanol-promoted desilylation of the resulting a minimum radical then generates the corresponding α-amino radical which couples with the C₆₀ radical anion to form the anion precursor of the fullerene adducts. The new approach using visible-light takes place under mild conditions and it does not require the use of photocatalysts. Thus, the method developed in this effort could broadens the range of functionalized fullerene derivatives that can be readily prepared.     

Highly efficient and stereoselective cycloaddition of nitrones to indolyl- and pyrrolylacrylates

The reactions of various nitrones with indolyl- and pyrrolylacrylates proceeds regioselectively with high diastereoselectivity in the case of aldonitrones, and represents an effective method for obtaining new indolyl- and pyrrolyl-substituted isoxazolidine carboxylates stabilized by weak (CH?O) and moderate (NH?N) strength intramolecular hydrogen bonding. The resulting cycloadducts exhibit promising in vitro anti-influenza activities.     

Transition metal-free direct amination of benzoxazoles using formamides as nitrogen sources

A transition metal-free method for the direct amination of benzoxazoles using formamides as nitrogen sources is reported, which was mediated by an inexpensive and environmentally friendly tetrabutylammonium iodide/tert-butyl hydroperoxide system and gave the 2-aminobenzoxazole derivatives with moderate to good yields.     

l-Proline-catalyzed five-component domino reaction leading to multifunctionalized 1,2,3,4-tetrahydropyridines

Multifunctionalized 1,2,3,4-tetrahydropyridines are concisely synthesized in good yields via l-proline-catalyzed or l-proline/FeCl₃-cocatalyzed one-pot multicomponent reactions (MCRs). The MCRs involve a domino hydroamination/prins reaction/Mannich-type reaction/intramolecular dehydration-cyclization process. The molecular structure of 5baa, one of multifunctionalized 1,2,3,4-tetrahydropyridines, was confirmed by single-crystal X-ray diffraction.     

Exploring the scope of the Gewald reaction: Expansion to a four-component process

An efficient four-component reaction was developed to take advantage of the reactivity of the 2-aminothiophene-3-carbonitrile functionality, which is obtained during the classical three-component Gewald reaction. Various α-methylene bearing ketones were reacted with malononitrile, elemental sulfur, and aryl/heteroarylnitrile derivatives in t-BuOH/NaOH to afford 2-arylthieno[2,3-d]pyrimidin-4-amines in high yields. Preliminary studies revealed the photophysical properties of the products and their potential for use as metal sensors.