α-吡唑基-N-苯基-α-氨基膦酸酯的合成及生物活性的初步研究

α－氨基膦酸及其酯与α－氨基酸结构类似,其具有抑菌［１］、抗肿瘤［２］、杀虫［３］以及抗植物病毒［４～７］的活性．α－氨基膦酸酯上与磷原子相连的２个烷氧基不同、α位碳原子以及氨基上取代基的不同将导致生物活性的巨大差异［８］．吡唑是一具有多种生物活性的...     

含有手性甲基膦酸酯基的十一聚核糖核苷酸的合成

含有手性甲基膦酸酯基的十一聚核糖核苷酸的合成周英姿，王来新，张礼和（北京医科大学天然药物及仿生药物国家重点实验室，北京，１０００８３）关键词酶性核酸，３＇，５＇－二胞嘧啶核苷甲基膦酸酯，立体化学，手性底物Ｃｅｃｈ［１］、Ａｌｔｍａｎ［２］和Ｓｙｍｏｎ...     

α-硫羰基硫代甲酰吗啉的合成及反应研究

α－硫羰基硫代甲酰胺类化合物于１９８０年被合成［１～３］，但对其性质、反应性及在有机化学中的应用尚未见报道．含有两个硫羰基的化合物为深红或深绿色晶体，反应活性较大，可作为有机合成原料、远红外吸收染料、激光Ｑ开关及有机导体等［４］．对该类化合物的研究具...     

取代苯甲醛肟羧酸酯的合成及生物活性研究(Ⅱ)——α-烷硫基苯甲醛肟羧酸酯的合成及生物活性

肟醚及肟酯衍生物是一类具有优良的杀虫、杀菌、杀螨及除草活性的化合物，有关此类化合物的研究非常活跃［１，２］．本研究组对拟除虫菊酯与芳香肟衍生物进行研究，发现菊酸肟酯类化合物具有良好的抗烟草花叶病毒和杀虫活性［３］．本文在前期研究工作的基础上，将烷硫基...     

二（三）苄基锡不饱和烃基膦酸酯的合成

合成了１０种二（三）苄基锡不饱和烃基膦酸酯［（ＰｈＣＨ２）ｎＳｎ］ｎ－１Ｏ２Ｐ（Ｏ）Ｒ（ｎ＝２，３；Ｒ＝—Ｃ≡ＣＰｈ，—Ｃ≡ＣＣ５Ｈ１１－ｎ，—Ｃ≡ＣＣＨ２ＯＣＨ３，—Ｃ≡ＣＣＨ２ＯＣ２Ｈ５，—ＣＨ＝ＣＣｌＰｈ），利用元素分析、核磁共振氢谱和ＴＧ－ＤＴＡ对其组成和结构进行了表征．初步生物活性测试表明，有些化合物具有较强的杀螨和杀菌活性     

α—[2—（2,4—二氯苯氧基）丙酰氧基]烃基膦酸酯的合成与生物活性

α┐［２┐（２．４┐二氯苯氧基）丙酰氧基］烃基膦酸酯的合成与生物活性贺红武刘钊杰＊汪军（华中师范大学有机合成化学研究所武汉４３００７９）（孝感师范高等专科学校化学系孝感）关键词羟基膦酸酯，合成，生物活性，除草剂１９９７－１０－２１收稿，１９９８－０４...     

(R)-N-酰基四氢噻唑-2-硫酮-4-羧酸在DCC存在下与胺的反应

由Ｎ－乙酰四氢噻唑－２－硫酮－４－羧酸（［α］２０Ｄ－１０９．８３°），及Ｎ－苯甲酰四氢噻唑－２－硫酮－４－羧酸（［α］２０Ｄ－１１２．２２°），在Ｎ，Ｎ′－二环己基二亚胺（ＤＣＣ）存在下分别与环己胺、苯胺反应得到光学活性产物（Ｒ）－Ｎ－乙酰四氢噻唑－２－硫酮－４－甲酰环己胺（［α］１７Ｄ－７４．５°），及（Ｒ）－Ｎ－苯甲酰四氢噻唑－２－硫酮－４－甲酰苯胺（［α］１９Ｄ－７．０４°）。用量子化学ＰＭ３方法研究了反应物和产物的电子结构。     

聚苯基膦酸双酚A酯的合成与表征

聚苯基膦酸双酚Ａ酯的合成与表征唐旭东陈晓婷王玉忠杨科珂王波（四川联合大学化学系成都６１００６４）吴大诚（四川联合大学轻纺学院成都６１００６５）关键词聚膦酸酯，阻燃剂，熔融缩聚，热性能聚膦酸酯类化合物是一类重要的磷系阻燃剂［１～３］，与传统的非聚...     

石墨电极上硫化钠的阳极氧化机理探索

电解硫化氢气体的碱性吸收液（Ｎａ２Ｓ表示）产生单质硫和氢气的研究是治理硫化氢废气的一种新方法［１ -７］,较之Ｃｌａｕｓ法有许多优点［３,４］,这对环境保护和资源回收均具有重要的实际意义．文献对硫化物水溶液电化学氧化机理的研究主要着重于在某些贵金属阳极上,包括某些硫化矿的湿法冶金反应过程的研究［８,９］,光电化学电池中使用多硫化物的研究［１０ -１３］,以及硫化物电解时产生单质硫的电催化活性研究［１４］等 ;但在石墨阳极上硫化物电化学氧化机理的研究报导却很少［３,４］．本文研究在石墨阳极上硫化钠水溶液…     

4－芳氧基－4－氧代－1，3，4－二氮磷杂环戊－2－硫酮类化合物的合成及其除草活性

４－芳氧基－４－氧代－１，３，４－二氮磷杂环戊－２－硫酮类化合物的合成及其除草活性陈茹玉，张成祥，冯克胜，程慕如（南开大学元素有机化学研究所天津３０００７１）关键词二氮磷杂环戊硫酮，酚类化合物，除草活性前文［１，２］曾报道含膦脲五员环类化合物的合成，...     

A confirmatory method for the simultaneous extraction,separation, identification and quantification of Tetracycline,Sulphonamide, Trimethoprim and Dapsone residues in muscle by ultra-high-performance liquid chromatography–tandem mass spectrometry according to Commission Decision 2002/657/EC

A rapid confirmatory multi-residue method for the analysis of tetracyclines, sulphonamides, trimethoprim and dapsone by UPLC-MS/MS is described. The method is able to quantify and confirm the following 19 compounds, oxytetracycline, tetracycline, chlortetracycline, doxycycline, sulfadiazine, sulfathiazole, sulfapyridine, trimethoprim, sulfamerazine, sulfamethizole, sulfamethazine, sulfamethoxypyridazine, sulfamonomethoxine, sulfachlorpyridazine, dapsone, sulfamethoxazole, sulfisoxazole, sulfaquinoxaline and sulfadimethoxine. Samples are extracted with 0.1 M EDTA and acetonitrile, which is then evaporated under a stream of nitrogen and reconstituted in water. Following centrifugation and filtering, an aliquot is analysed by UPLC-MS/MS using positive electrospray ionisation and multiple reaction monitoring. The method is deemed rapid as all analytes are extracted by a single extraction technique, with no solid-phase extraction clean up required. Validation is according to Commission Decision 2002/657/EC and was carried out for bovine, porcine, ovine and poultry species. Specificity, recovery, repeatability, reproducibility, CCα and CCβ data is presented.     

电感耦合等离子发射光谱法测定镍铁中Si,Mn,P,Ni

建立ICP–AES法测定新型材料镍铁中的Si,Mn,P,Ni元素的方法。考察了镍铁基体和共存元素对测定结果的影响。通过基体匹配消除基体干扰,确定各待测元素谱线为Mn 293.930 nm,P 178.280 nm,Ni 231.604 nm,Si251.611 nm。Si,Mn,P,Ni的检出限分别为0.06,0.04,0.08,0.04 mg/L,测定结果的相对标准偏差均小于5%(n=11),加标回收率在95%~105%之间。该方法操作简便、测定结果准确可靠,可用于镍铁中Si,Mn,P,Ni的含量测定。     

电感耦合等离子体原子发射光谱法测定纯银中镉、铋、铁、铅、锑、钯、硒、碲

样品用硝酸溶解,加入过量盐酸沉淀分离银,过滤后利用电感耦合等离子体原子发射光谱法测定镉、铋、铁、铅、锑、钯、硒、碲,方法检出限分别为:0.0028,0.0075,0.0036,0.011,0.010,0.021,0.0075,0.0039μg/mL;加标回收率为98.1%～114.3%;RSD小于4.2%,方法能同时准确测定镉、铋、铁、铅、锑、钯、硒、碲,满足日常分析要求。     

微波消解-微波等离子体矩原子发射光谱法测定乳胶管中的铁、钙、镍、镁、锌

本文研究了用HNO3-H2O2微波消解样品,微波等离子体矩原子发射光谱(MPT-AES)测定乳胶管中铁,钙,镍,镁,锌的含量方法。详细考察了测定铁、钙、镍、镁、锌的最佳实验条件,以及介质酸、共存离子的影响。本方法测定铁、镍、镁、钙、锌的检出限分别为77.80、7.55、2.70、275.87、46.23 ng/mL,方法的精密度分别为3.10%、2.19%、2.22%、1.27%、2.90%,线性范围分别为0.08~2 mg/L0、.06~2 mg/L0、.001~3 mg/L、0.005~2 mg/L、0.05~1 mg/L,加标回收率分别在97.7%~107.8%、96.0%~106.7%、98.0%~106.2%、92.3%~108.8%、98.7%~106.8%范围。     

Simultaneous analysis of pesticides from different chemical classes by using a derivatisation step and gas chromatography-mass spectrometry

This work presents a new method to analyse simultaneously by GC–MS 31 pesticides from different chemical classes (2,4 D, 2,4 MCPA, alphacypermethrin, bifenthrin, bromoxynil, buprofezin, carbaryl, carbofuran, clopyralid, cyprodinil, deltamethrin dicamba, dichlobenil, dichlorprop, diflufenican, diuron, fenoxaprop, flazasulfuron, fluroxypyr, ioxynil, isoxaben, mecoprop-P, myclobutanil, oryzalin, oxadiazon, picloram, tau-fluvalinate tebuconazole, triclopyr, trifluralin and trinexapac-p-ethyl). This GC–MS method will be applied to the analysis of passive samplers (Tenax^® tubes and SPME fiber) used for the evaluation of the indoor and outdoor atmospheric contamination by non-agricultural pesticides. The method involves a derivatisation step for thermo-labile or polar pesticides. Different agents were tested and MtBSTFA (N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide), a sylilation agent producing very specific fragments [M−57], was retained. However, diuron could not be derivatised and the isocyanate product was used for identification and quantification. Pesticides which did not need a derivatisation step were not affected by the presence of the derivatisation agent and they could easily be analysed in mixture with derivatised pesticides. The method can be coupled to a thermal-desorption unit or to SPME extraction for a multiresidue analysis of various pesticides in atmospheric samples.     

Inorganic arsenic: A dangerous enigma for mankind

Human being have been using inorganic arsenic for a long time. Many reports on arsenic poisoning have been published: eg case reports, examination reports, post mortem reports, and epidemiological studies. Several aspects and features of arsenic poisoning are discussed in this report. Methods of inferring arsenic-related disease, disease classification according to acute or chronic criteria, exposure route, interaction, confounding factors, and the oxidation state of arsenic are all discussed. The effects of arsenic are classified into skin, respiratory system, gastrointestinal tract, liver, cardiovascular system, nervous system, and bone marrow effects. Carcinogenicity is an important chronic effect of arsenic poisoning, so special attention is paid to it in this review. In Japan, there have been many incidents of arsenic poisoning. In this review, we often use data from these cases, such as the Morinaga powdered-milk poisoning case, the Ube soy-sauce poisoning case, the Toroku mine incident, and the Nakajo well-water poisoning case. We emphasize here the necessity of planning follow-up studies and total health care for patients exposed to arsenic.     

Three types of reactions with intramolecular five-membered ring compounds in organic synthesis

There are three types of reactions with intramolecular five-membered ring compounds in organic syntheses: The first type is reactions involving intramolecular five-membered ring compounds which are utilized for the ease of synthesis of these compounds and the stability of the products. The second is reactions performed via intramolecular five-membered ring intermediates, because such intermediates are very reactive and labile compounds. The third is the metal-catalyzed reactions with the intramolecular five-membered ring compounds because these metal compounds have catalytic activities. The third type reactions involving intramolecular five-membered ring pincer compounds are also provided.The first type reactions include carbonylations, alkenylations, alkynylations, acylations, isocyanations, Diels-Alder reactions, etc. The second type reactions include carbonylations, cross-coupling reactions, hydroacylations, ring expansion reactions, carbocyclizations, etc. The third type reactions include cross-coupling reactions, rearrangements, metatheses, reductions, Michael reactions, dehydrogenations, Diels-Alder reactions, etc.     

铋系超导体组成分析

本文首次提出了一种离子交换柱分离——滴定法测定Bi系超导体中Bi、Pb、Cu、Ca和Sr含量的方法。研究了进样条件和淋洗方法,特别是Bi~(3+)在微酸性溶液中的亚稳态进样。测定合成样品时,Bi、Pb、Cu、Ca和Sr的相对标准偏差分别为0.7％、1.6％、0.5％、0.4％和0.2％。分析了超导体样品,并测定了其中Cu~(3+)。     

Nondestructive characterization of nanoscale layered samples

Multilayered samples consisting of Al, Co and Ni nanolayers were produced by MBE and characterized nondestructively by means of SRXRF, μ-XRF, WDXRF, RBS, XRR, and destructively with SIMS. The main aims were to identify the elements, to determine their purity and their sequence, and also to examine the roughness, density, homogeneity and thickness of each layer. Most of these important properties could be determined by XRF methods, e.g., on commercial devices. For the thickness, it was found that all of the results obtained via XRR, RBS, SIMS and various XRF methods (SRXRF, μ-XRF, WDXRF) agreed with each other within the limits of uncertainty, and a constant deviation from the presets used in the MBE production method was observed. Some serious preliminary discrepancies in the results from the XRF methods were examined, but all deviations could be explained by introducing various corrections into the evaluation methods and/or redetermining some fundamental parameters.     

Determination of the Pesticides Alachlor,Anilazine, Bromoxynil,and Dichlobenil by Low Temperature Phosphorimetry

Abstract

Sensitive low temperature phosphorimetric methods for the determination of the pesticides Alachlor, Anilazine, Bromoxynil, and Dichlobenil in EPA solvent have been developed. The minimum detectable amounts are 0.08, 0.006, 0.2, and 0.006 p.p.m. for Alachlor, Anilazine, Bromoxynil, and Dichlobenil respectively. The ranges in linearity of the analytical calibration graphs are 0.01–5, 0.2–7.5, and 0.03–20 p.p.m. for Anilazine, Bromoxynil, and Dichlobenil respectively. The analytical calibration graph for Alachlor is linear from 0.3 to 10 p.p.m. and with a different slope, linear from 10 to 50 p.p.m. The procedure for Alachlor has been applied to the analys of a solid commercial formulation.