烟草与尿样中的代谢标记物

卷烟烟气进入人体后会对人体的代谢物产生影响,目前研究较多的是稠环芳烃类、烟草特有亚硝胺类和尼古丁的代谢物。文章分别介绍了稠环芳烃类代谢物1-羟基芘,烟草特有亚硝胺类代谢物NNAL和NNAL-Gluc,尼古丁的代谢物可天宁,对这些代谢物的检测方法、体内的含量水平、各种条件的影响进行了综述。     

抽吸过程中尼古丁在烟丝和滤咀中分布的研究

吸烟有害健康。尤以香烟中尼古丁对人体健康的危害 ,已众所周知。美国卫生局和各种癌症研究机构一再就吸烟的危害对人们作出警告 ,但人们所吸的烟还是比以往任何时候都要多 ,完全消灭吸烟在相当长时期内难以实现。因此 ,研究吸烟过程中尼古丁在香烟中的分布情况 ,寻找较为安全、适宜的吸烟区间 ,减少吸烟过程中尼古丁对人体健康的危害 ,成为本文关心的问题。为了降低烟草中有害物质对人体的危害 ,目前在国内外 ,一般均在香烟上加一过滤咀 ,以吸滤烟草中部分尼古丁及其它物质。因而 ,为了提高滤咀对其尼古丁的吸滤率 ,在滤咀中添加油酸酰胺、…     

高效液相色谱法快速测定烟丝水提取液中尼古丁和可天宁生物碱

建立了烟丝水提取液中尼古丁和可天宁生物碱的高效液相色谱(HPLC)快速检测方法。色谱柱为ZORBAX Eclipse Plus C18柱,流动相为甲醇-0.02 mol/L KH2PO4-三乙胺(体积比10∶90∶0.05,pH=3.2)。将该方法用于不同品牌香烟烟丝中尼古丁和可天宁的含量分析,结果显示黄山、白沙、万宝路和广东湛江廉江烟丝厂烟丝中尼古丁生物碱含量分别为10.59±0.77 mg/g、13.53±0.38 mg/g、10.82±0.41mg/g和10.89±0.92mg/g;可天宁生物碱含量分别为0.53±0.04mg/g、0.38±0.02mg/g、0.24±0.01mg/g和0.51±0.001mg/g。     

尼古丁PVC膜选择电极的研制

尼古丁是一类有机吡啶衍生物的生物碱,存在于烟草中,毒性极大。在烟草生产过程中,其含量是一项质量控制指标。尼古丁的化学名称为1-甲基-2(2-吡啶基)吡咯烷,结构式如下:尼古丁一般常用薄层色谱法和毛细管气液色谱法进行测定。目前国外标准是采用紫外分光光度法,但必须用蒸气蒸馏法从烟草混合物中进行分离后,才能测定。尼古丁PVC膜选择电极国内尚未报道,国外报道了液膜尼古丁电极及其性能。作者     

烟草中不同部位尼古丁含量的测定与比较

利用示波极谱法直接测定了贵州、云南、河南和四川四个烟草盛产地所产烟草的烟叶和烟茎中不同部位的尼古丁含量,并对测定结果进行了比较。结果显示:各地烟草上部烟叶尼古丁含量最高,中部次之,下部尼古丁含量最低;尼古丁在茎部的分布以中部最高,下部次之,上部最少。烟叶中的尼古丁含量又远高于其相应的茎。     

研究阐述尼古丁等环境毒物降解机制

<正>近期,上海交通大学生命科学技术学院教授许平团队在微生物分解代谢研究领域获得突破,进一步阐明尼古丁等环境毒物的降解机制。日前,相关研究成果以封面论文形式发表于《分子微生物学》。在烟草加工过程中会产生大量富含尼古丁等烟碱类化合物的固体和液体废弃物,这些物质易进入地下水,并对环境造成一定的影响,因此降低烟草废弃物中尼古丁含量对于保护环境有着重要的意义。恶臭假单胞菌S16能够以尼古丁作为底物生长并将其完全矿化,在降低烟草中尼古丁含量和处理烟草废物的过程中发挥重要作用。课题组成员在研究假单胞菌属中参与重要环境毒物尼古丁分解代谢     

毛细管电泳-电致化学发光联用技术检测烟草中尼古丁含量

建立了毛细管电泳-电致化学发光联用技术(CE-ECL)检测烟草浸出液中尼古丁含量的方法。考察了检测电位、检测池中Ru(bpy)32+浓度和缓冲液pH值、CE运行缓冲液浓度和pH值、进样时间和电压,以及CE分离电压等实验条件对尼古丁测定的影响。在优化的条件下,尼古丁检测的线性范围为低浓度段:1～100μg/L(r>0.999)、高浓度段:100～1500μg/L(r>0.996),检出限为0.5μg/L(S/N=3)。将本方法用于3种品牌的烟草浸出液中尼古丁含量的测量,测定值均与烟盒上尼古丁的标注值相吻合,样品的加标回收率为95%～106%。     

烟草薄片热解产物的同步辐射真空紫外光电离质谱研究

利用同步辐射真空紫外光电离质谱的方法对烟草薄片热解产物进行了实时在线质谱检测。通过改变同步辐射光子的能量,获得了不同光子能量下的质谱图。在已有文献及量子化学计算的辅助下,给出了一些主要热解产物的化学信息。尼古丁(m/z 162)是传统烟草原料的主要热解产物之一,但并不是烟草薄片的主要热解产物,添加烟草薄片也许是一种降低尼古丁的有效途径。     

亲水作用色谱-串联质谱测定尿液中尼古丁和可替宁

建立了测定人尿液中尼古丁和可替宁含量的亲水作用色谱-串联质谱(HILIC-MS/MS)方法。尿样加入尼古丁-d4和可替宁-d3同位素内标后,用水稀释10倍,经过滤后的滤液由超高效液相色谱-串联质谱(UPLC-MS/MS)进行分离分析。采用ACQUITY UPLC~BEH HILIC色谱柱(50 mm×3.0 mm,1.7μm),以甲醇和体积分数为0.1%的氨水为流动相,流速为0.2 mL/min,在电喷雾电离源正离子模式下测定尿液中尼古丁和可替宁的含量,用标准曲线法定量。尼古丁和可替宁在1.0~1 000μg/L范围内线性关系良好,相关系数分别为0.994 9和0.995 8;检出限分别为0.082μg/L和0.077μg/L;定量限分别为0.27μg/L和0.26μg/L;加标回收率分别为90.4%~103.5%和93.0%~104.6%;相对标准偏差分别为4.80%~6.21%和4.22%~7.15%。应用所建立的方法测定了200份尿样,结果表明,吸烟人群尿中尼古丁含量为26.68~854.30μg/L,可替宁含量为36.66~1 191.18μg/L(n=86,M_(nicotine)=76.00μg/L,M_(nicotine)=83.52μg/L,M为中位数);非吸烟人群尿中尼古丁含量为5.08~69.66μg/L,可替宁含量为3.16~28.21μg/L(n=114,Mnicotine=7.53μg/L,M_(nicotine)=3.79μg/L)。该方法快速灵敏,操作简单,适用于尿样中尼古丁和可替宁的批量测定,能满足烟草暴露评价的需要。     

溶剂萃取-毛细管气相色谱法测定烟草中主要生物碱

报道了用毛细管柱气相色谱同时测定烟草中尼古丁、去甲基尼古丁、新烟碱和去氢新烟碱4种主要生物碱的方法。烟草样品经二氯甲烷／甲醇(V/V,3：1)溶剂萃取,过一次性滤膜,直接进样,经HP-5MS毛细管柱分离,氮磷检测器(NPD)检测。该方法简单,重现性好;4种生物碱相对标准偏差为1．5％～3．4％;加标回收率为93．6％～102．4％。     

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.