快速柱前衍生HPLC法检测曲格列汀中(R)-3-氨基哌啶

以邻苯二甲醛(OPA)和3-巯基丙酸为衍生试剂,建立了柱前衍生高效液相色谱(HPLC)测定曲格列汀中(R)-3-氨基哌啶含量的分析方法。(R)-3-氨基哌啶与衍生剂在碱性(p H 10.5)条件下于室温反应30s,进行柱前衍生,并利用高效液相色谱-质谱对衍生产物进行定性分析。采用YMC-Triart C18色谱柱(150 mm×4.6 mm,5μm)分离,流动相采用0.05 mol/L乙酸钠(p H 6.0)-甲醇溶液,梯度洗脱,流速1.0 mL/min,检测波长331 nm,柱温30℃。(R)-3-氨基哌啶质量浓度在0.08~2.0μg/mL范围内线性关系良好(r=0.9993),定量限为1.6 ng,加标回收率在98.0%~10⁶.9%之间,相对标准偏差(RSD)为2.8%。该方法可用于曲格列汀中(R)-3-氨基哌啶含量测定。     

柱前衍生HPLC-MS法测定海藻中脂肪酸

建立以N,N-二甲基乙二胺作为柱前衍生试剂,在C18反相色谱柱上,采用梯度洗脱,电喷雾电离源测定羊栖菜、紫菜、海带中饱和脂肪酸和不饱和脂肪酸的柱前衍生高效液相色谱串联质谱法。各脂肪酸衍生物均在进样质量浓度为2~100μg/m L时表现出良好的线性关系,相关系数均≥0.9905。检出限(LODs)在20~50 ng/m L之间,方法比未衍生脂肪酸的方法提高了1000倍左右的灵敏度。     

高效液相色谱-二极管阵列检测法测定L-丙氨酸与L-氨基丙醇

建立了柱前衍生同时测定L丙-氨酸、L氨-基丙醇的高效液相色谱方法。色谱条件为:Shim-pack VP-ODS柱(150 mm×4.6 mm.ID.,5μm);二极管阵列检测器;流动相为甲醇-磷酸盐缓冲溶液(NaH2PO4浓度为0.02 mol/L,pH 4.00 H3PO4调节)(体积比为30∶70),流速为0.5 mL/m in,检测波长为222 nm,柱温为30℃。L丙-氨酸与L氨-基丙醇的线性范围分别为2.30~178 mg/L和9.3~8690 mg/L;检出限分别为1.1 mg/L和1.6 mg/L;日内、日间测定的相对标准偏差(RSD)分别为0.22%、0.46%和0.02%、0.03%。     

高效液相色谱/荧光法测定血浆、红细胞与尿液中的硫胺素及其磷酸酯

建立了同时测定血浆、红细胞、尿液中硫胺素(T)、一磷酸硫胺素(TMP)、二磷酸硫胺素(TDP)的柱前衍生/反相高效液相色谱-荧光检测法。样品经高氯酸除蛋白,铁氰化钾衍生后,采用反相色谱柱分离,荧光检测器测定,外标法定量。色谱柱为C18柱(250 mm×4.6 mm,5μm i.d.),流动相为0.2 mol/L KH2PO4溶液(pH 7.0,含0.000 3 mol/L四丁基氢氧化铵)-甲醇和甲醇-水,采用梯度程序进行洗脱,流速为0.8mL/min。荧光检测器激发波长为365 nm,发射波长为435 nm。结果表明:T,TMP在0.5~20.0μg/L,TDP在5.0~200.0μg/L质量浓度范围内呈良好的线性关系,相关系数分别为0.99,0.98,0.99。T,TMP,TDP的平均回收率为86.8%~110.2%,相对标准偏差(RSDs)为2.5%~10.9%。3种化合物在血浆及红细胞中的检出限(LODs)为0.03~0.35μg/L,定量下限(LOQs)为0.09~1.18μg/L。T在尿液中的检出限(LODs)为1.58μg/L,定量下限(LOQs)为5.26μg/L。该方法的准确度和精密度均较高,能够满足临床检测和科研需要。     

3,3′-二氨基联苯胺柱前衍生高效液相色谱法测定酒中双乙酰

以3,3′-二氨基联苯胺(DAB)为衍生化试剂,建立了柱前衍生高效液相色谱测定酒中双乙酰含量的分析方法。双乙酰与衍生化试剂DAB在室温条件下反应10 min进行柱前衍生,并采用Shim-pack VP-ODS色谱柱(250mm×4.6 mm,4.6μm)对衍生化产物进行分离分析,以水-甲醇为流动相进行梯度洗脱,流速为0.7 mL/min,并采用配有二极管阵列检测器(DAD)的高效液相色谱仪测定,检测波长为254 nm。该法在双乙酰浓度为0.20~180μmol/L的范围内呈现良好的线性关系,相关系数(R2)为0.999,检出限(S/N=3)为0.09μmol/L,定量限(S/N=10)为0.20μmol/L,日内精密度(RSD)为1.28%(n=6)。实际酒样品的加标回收率为92.0%~103.6%,RSD为0.69%~3.45%(n=3)。该法简便快捷,结果准确,稳定性好,可以用于白酒及红酒中双乙酰含量的测定。     

超高效液相色谱-串联质谱法测定食用植物油中胆固醇含量

提出了食用植物油中胆固醇的超高效液相色谱-串联质谱测定方法。食用植物油经皂化后用石油醚-乙醚(1+1)溶液提取,以Waters ACQUITY UPLC BEH C18色谱柱(50mm×2.1mm,5μm)为分离柱,以甲酸-甲醇(0.1+99.9)溶液为流动相,以2,2,3,4,4,6-d6胆固醇为内标,采用大气压化学电离源在多反应监测负离子模式下进行测定,胆固醇和内标的定量离子对分别为m/z369.2/146.9,369.2/160.9和375.2/166.5。胆固醇在0.1～5mg·L-1范围内呈线性,测定下限(10S/N)为0.02ng。在3个浓度水平上对方法做回收试验,测得回收率在102%～110%之间。     

柱前衍生高效液相色谱法测定尼莫地平注射液中的甲醛和乙醛

建立柱前衍生高效液相色谱测定尼莫地平注射液中甲醛和乙醛含量的方法.以2,4-二硝基苯肼为衍生化试剂,室温反应30 min,采用高效液相色谱法检测,色谱柱为Waters XBridge C8柱(250 mm×4.6 mm,5μm),流动相为乙腈–水(体积比为50:50),等度洗脱,流量为1.0 mL/min,柱温为30℃...     

OPA-FMOC在线柱前衍生化HPLC法测定甘露聚糖肽中氨基酸组成及含量

建立了OPA-FMOC在线柱前衍生化高效液相色谱法测定甘露聚糖肽中氨基酸组成及含量的方法,采用色谱柱为Agilent ZORBAX Eclipse XDB-C18柱(250 mm×4.6 mm,5μm),流动相A为40 mmol/L Na_2HPO_4缓冲溶液(pH 7.8);流动相B为甲醇:乙腈:水(45∶45∶10,V/V/V);梯度洗脱;流速:1.5 m L/min;柱温:40℃;检测波长:338,262 nm。20种氨基酸在53 min内得到较好地分离,各氨基酸在5~500μg/m L范围内线性关系良好,相关系数在0.9941~0.9999之间;平均加标回收率在85.6%~102.6%之间;检出限在0.56~8.33 ng(进样量1μL)范围内。甘露聚糖肽样品中含有16种氨基酸,氨基酸总量平均为3.56%(n=3)。     

脑蛋白水解物中氨基酸的柱前衍生高效液相色谱测定

通过升高色谱柱温度,结合线性梯度洗脱的分离模式调整色谱分离的选择性,提出了一种测定脑蛋白水解物注射液中氨基酸含量的2,4-二硝基氟苯(DNFB)柱前衍生高效液相色谱方法。本法采用Kromasil C18(250×4.6 mm i.d.,5μm)色谱柱,柱温44℃,在30 min内以3个线性梯度能完全分离17种氨基酸,定量线性范围为0.2~1.0mg/L;加标回收率为89%~108%。该法具有适用性好、稳定性高等特点,也可以应用于其它种类样品中氨基酸的测定。     

固相萃取/~(18)O标记高氯酸根稀释高效液相色谱-串联质谱法测定水果中的高氯酸盐

建立了水果中高氯酸盐的高效液相色谱-串联质谱分析检测方法。样品采用1%乙酸提取,C18固相萃取柱净化,Waters IC-Pak Anion HR(4.6 mm×75 mm)色谱柱洗脱,流动相为乙腈-100 mmol/L乙酸铵溶液(体积比60∶40),流速0.7 m L/min;液相色谱-三重四极杆质谱联用技术-电喷雾负离子监测模式检测,采用18O标记高氯酸根离子作为内标进行基质校正,内标法定量。结果表明:高氯酸盐在0.1~10.0μg/L范围内线性关系良好,定量下限为1.0μg/kg;在1.0,2.0,10μg/kg 3个加标水平下的回收率为92.5%~110%,相对标准偏差(RSD)为1.4%~5.4%。实际样品检测表明该方法准确可靠,适合于水果中高氯酸盐的测定。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.