稳健回归解析紫外光度法同时测定磺胺甲唑和甲氧苄啶

磺胺甲噁唑和甲氧苄啶的紫外光谱严重重叠,本文构造和使用两个M估计的新的目标函数导函数(x)函数,并由此建立两个新稳健回归方法,以此解析重叠的吸收光谱,不经分离紫外分光光度法同时测定磺胺甲噁唑和甲氧苄啶,结果满意。为多组分同时测定提供了两个新稳健回归方法。     

快速溶剂萃取-凝胶渗透色谱净化-液相色谱-质谱法测定动物肝组织中雷公藤甲素和雷公藤酯甲

提出了动物肝组织中雷公藤甲素与雷公藤酯甲的液相色谱-质谱法分析方法。用快速溶剂萃取仪用乙腈将动物肝组织中雷公藤甲素与雷公藤酯甲萃取到有机相,提取液经凝胶渗透色谱净化除去基质的干扰,所得洗脱液40℃氮吹挥干后用甲醇定容至0.5mL,用液相色谱-质谱法测定。雷公藤甲素与雷公藤酯甲的质量浓度均在5～1 000μg.L-1范围内呈线性,检出限(3S/N)均为1.0μg.L-1。在动物肝组织中用标准加入法做回收及精密度试验,结果为:雷公藤甲素和雷公藤酯甲的回收率分别在69.3%～77.8%,73.1%～77.2%之间;雷公藤甲素和雷公藤酯甲测定值的相对标准偏差(n=5)分别在3.2%～3.3%,2.3%～3.0%之间。     

近红外光谱技术应用于摇头丸中MDMA、MA无损定量分析的研究

提出了用近红外漫反射光谱快速无损测定摇头丸中亚甲二氧基甲基苯丙胺(MDMA)、甲基苯丙胺(MA)含量的新方法。收集含MDMA摇头丸56份和含MA摇头丸58份,采用GC-MS确定其中MDMA和MA质量分数分别为0.64%~53.83%,0.37%~5.81%。在12000~4000 cm-1扫描样品,以交叉验证误差均方根(RMSECV)为指标,通过筛选,对各组分确定了用于建模的最优近红外波段和光谱预处理方法,采用偏最小二乘算法建立了近红外光谱与这2组分GC-MS分析值之间的校正模型,并以此分别预测21个样本。δ代表预测样本NIR值/GC-MS值,MDMA和MA在裸片和塑料包装中δ值的均值为99%、101%、100%、101%,RSD分别为7.33%、20.3%、4.52%、12.3%。该方法可对摇头丸裸片中MDMA和MA进行快速无损分析,结果可靠,为刑事案件中毒品成分的测定提供了一种新的分析手段。     

稳健回归解析紫外光度法同时测定磺胺甲恶唑和甲氧苄啶

磺胺甲恶唑和甲氧苄啶的紫外光谱严重重叠,本文构造和使用两个M估计的新的目标函数导函数Ψ（x)函数,并由此建立两个新稳健回归方法,以此解析重叠的吸收光谱,不经分离紫外分光光度法同时测定磺胺甲恶唑和甲氧苄啶,结果满意,为多组分同时测定提供了两个新稳健回归方法。     

分子连接性指数~mX~z与不饱和链烃沸点的定量关系研究

提出了一个计算分子中成键原子点价δ_i~z的新方法，以δ_i~z为基础建构的 新的分子连接性指数为~mX~z = ∑(δ_i~z·δ_j~z·δ_k~z……)~(-0.5)，其中 ~0X~z，~1X~z的定义为：~0X~z = ∑(δ_i~z)~(-0.5), ~1X~z = ∑(δ_i~z·δ _j~z)~(-0.5)，并研究了~0X~z,~1X~z与不饱和链烃沸点的相关性。结果表明，该 拓扑指数具有良好的结构-性质相关性。以~0X~z,~1X~z和碳原子数N为结构参数分 别与80个单烃烃、39个单炔烃、169个不饱和链烃（包括烷烃、炔烃及烯炔）的沸 点进行关联所得到的三元回归方程为：单烯烃，log(779.13-bp) = 2.822433-0. 0133346 ~0X~z - 0.0638379 ~1X~2 + 0.0111229N (R = 0.99895, F = 202783. 65, s = 3.36)；单炔烃，log(797.47-bp) = 2.809912-0.0108374~0X~z - 0. 0864540 ~1X~z + 0.0233028N (R = 0.99935, F = 98657.36, s = 3.65);不饱和 链烃，log(741.26-bp) = 2.779526 + 0.0194388~0X~z - 0.0519158~1X~z - 0. 0211047N (R = 0.99467, F = 82387.26, s = 7.74)。应用这些经验公式可以预测 不饱和链烃的沸点。     

Mo2［(p-tol)NCHN(p-tol)］4及其阳离子电子结构和电子吸收光谱的从头算研究

用密度泛函理论中的B3LYP方法, 采用LanL2DZ基组, 对Mo2(form)4和［Mo2(form)4］+{其中(form)-=［(p-tol)NCHN(p-tol)］-)}, 进行了分子轨道计算, 明确了Mo—Mo键具有σ2π4δ2四重键的性质. 计算得到Mo—Mo间的分子轨道顺序为π<σ<δ<σ*<δ*<π*. 用单激发组态相互作用（CIS）方法计算了Mo2(form)4和［Mo2(form)4］+的电子吸收光谱, Mo2(form)4的最低能吸收光谱λ=390 nm, 是1A1g→1Eg跃迁产生的, 属于金属内部的电荷迁移. ［Mo2(form)4］+的最低能吸收光谱λ=1 096 nm, 也是1Ag→1Eg跃迁产生的, 属于金属内部的电荷迁移.     

N,N′-双间甲苯基-3,6-二甲基-1,4-二氢-s-四嗪-1,4-二甲酰胺的合成和晶体结构

间甲苯基异氰酸酯与 3 ,6 二甲基 1,6 二氢 s 四嗪反应生成标题化合物 (C2 0 H2 2 N6O2 ,Mr=3 78 44 ) .经X射线单晶结构分析表明 ,此晶体属正交晶系 ,P2 12 12 1空间群 ,晶胞参数分别为 :a =1 160 2 ( 2 )nm ,b =1 5 92 1( 3 )nm ,c=1 3 918( 3 )nm ,V =1 9874( 10 )nm3 ,Z =4,Dc=1 2 65g/cm3 ,μ(MoKα) =0 0 86mm-1,F( 0 0 0 ) =80 0 ,R和wR分别是 0 0 619和 0 14 95 .结果表明该化合物的两个酰胺基接在s 四嗪环的 1,4 位 ,而四嗪环呈船式构象 ,不具有同芳香性 ,分子中存在氢键 .     

新型N-取代邻苯二甲酰亚胺-4-甲酰胺衍生物的合成及抗癌活性

以1,2,3-苯三甲酸为原料,依次经分子内脱水、胺解反应和酰胺缩合三步反应合成了19个新型N-取代邻苯二甲酰亚胺-4-甲酰胺衍生物作为聚腺苷二磷酸核糖聚合酶1（PARP-1）抑制剂（4a~4s）,其结构经¹H NMR,¹³C NMR和HR-MS(ESI-TOF)表征。采用MTT法研究了4a~4s对胰腺癌细胞系Capan-1的体外抗癌活性测试,测试结果显示：对Capan-1的抑制最强活性是4r（IC₅₀=0.19μM）,是模板化合物NMS-P118(IC₅₀=2.20μM)的11倍。      

共振瑞利散射光谱法测定甲砜霉素——基于与溴甲酚绿的反应

在pH 7.56的Tris-盐酸缓冲溶液中,一定量的甲砜霉素与1.0×10^-3mol·L^-1溴甲酚绿溶液1.5 mL在总体积10 mL中反应生成离子缔合物,产生共振瑞利散射光谱,在其最大共振光散射峰波长340 nm处测定共振瑞利散射的强度I_RRS。甲砜霉素的质量浓度在0.02～0.36 mg·L^-1范围内与扣除空白值的相应共振瑞利散射强度△I_RRS呈线性关系,方法的检出限（3s/k）为0.065 mg·L^-1。方法用于测定两种甲砜霉素药物中甲砜霉素的含量,并以此试样为基体,用标准加入法做回收率和精密度试验,测得其平均回收率在98.9%～102%之间,相对标准偏差（n=6）在1.4%～1.7%之间。     

~1H核磁共振法测定三氯生的纯度

以丙烯酰胺为内标,氘代二甲基亚砜(DMSO-d6)为溶剂,对用1 H核磁共振法测定三氯生纯度条件进行试验。在脉冲延迟时间20s和扫描次数64等条件下得到1 H-NMR谱图。选择H-11(δ6.88)和δ5.59分别作为样品和内标的定量峰,取其积分峰面积平均值按公式计算三氯生的纯度。结果表明:样品与内标物的质量比在1.01~10.16内,与其定量峰面积比值呈线性关系。平行测定同一样品6份,按所得样品对内标物定量峰面积的比值,计算其相对标准偏差(n=6)为0.12%。按所提出方法分析了三氯生实样,结果的平均值(n=3)为99.78%,与质量平衡法所得结果(99.81%)相符。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.