一种结构新颖的肟醚类化合物的合成及其生物活性研究

以苯并五元环为基本结构对肟醚类strobilurin杀菌剂侧链进行修饰, 共设计合成了13个结构新颖的肟醚类化合物. 室内生物活性测试结果表明所合成的化合物对小麦白粉病(Eryiphe graminis)和黄瓜霜霉病(Pseudoperonospora cubensis)均具有优异的抑菌活性, 而所合成的部分茚取代肟醚类化合物还具有广谱的杀虫活性. 同时, 用钯催化“一锅法”反应以较高的收率合成了关键中间体2-乙酰基茚衍生物.     

A New Saponin Transformed from Ginsenoside Rh1 by Bacillus subtilis

A novel saponin was isolated from the transformed products of ginsenoside Rh1 by Bacillus subtilis. It‘s structure was determined to be 3-O-β-D-glucopyranosyl-6-O-β-D-glucopyranosyl-20 (S)-protopanaxatriol on the basis of the spectral data.     

对流层夜间化学研究

NO3自由基与N2O5是对流层夜间化学的关键物种。一方面NO3与O3等组分是夜间大气中的重要氧化剂，与它们的反应是生物排放挥发性有机物（VOCs）的主要汇；另一方面NO3与N2O5和雨滴或气溶胶颗粒物发生的异相反应则是大气中氮氧化合物NOx（NO，NO2）的主要清除过程，从而可以减轻对流层臭氧污染。研究它们的化学反应性质及对其进行实地测量，对深入理解大气氧化过程和全面了解区域乃至全球大气自净能力有重要意义。本文总结了近年来有关夜间化学的研究成果，介绍了以NO3和N2O5为中心的基本夜间化学过程、对流层中NO3与N2O5的源与汇以及外场测量技术的最新研究进展，并提出了尚待解决的一些问题。     

DPPH (= 2,2‐Diphenyl‐1‐picrylhydrazyl = 2,2‐Diphenyl‐1‐(2,4,6‐trinitrophenyl)hydrazyl) Radical‐Scavenging Reaction of Protocatechuic Acid Esters (= 3,4‐Dihydroxybenzoates) in Alcohols: Formation of Bis‐alcohol Adduct

Protocatechuic acid esters (= 3,4‐dihydroxybenzoates) scavenge ca. 5 equiv. of radical in alcoholic solvents, whereas they consume only 2 equiv. of radical in nonalcoholic solvents. While the high radical‐scavenging activity of protocatechuic acid esters in alcoholic solvents as compared to that in nonalcoholic solvents is due to a nucleophilic addition of an alcohol molecule at C(2) of an intermediate o‐quinone structure, thus regenerating a catechol (= benzene‐1,2‐diol) structure, it is still unclear why protocatechuic acid esters scavenge more than 4 equiv. of radical (C(2) refers to the protocatechuic acid numbering). Therefore, to elucidate the oxidation mechanism beyond the formation of the C(2) alcohol adduct, 3,4‐dihydroxy‐2‐methoxybenzoic acid methyl ester ( 4 ), the C(2) MeOH adduct, which is an oxidation product of methyl protocatechuate ( 1 ) in MeOH, was oxidized by the DPPH radical (= 2,2‐diphenyl‐1‐picrylhydrazyl) or o‐chloranil (= 3,4,5,6‐tetrachlorocyclohexa‐3,5‐diene‐1,2‐dione) in CD₃OD/(D₆)acetone 3 : 1). The oxidation mixtures were directly analyzed by NMR. Oxidation with both the DPPH radical and o‐chloranil produced a C(2),C(6) bis‐methanol adduct ( 7 ), which could scavenge additional 2 equiv. of radical. Calculations of LUMO electron densities of o‐quinones corroborated the regioselective nucleophilic addition of alcohol molecules with o‐quinones. Our results strongly suggest that the regeneration of a catechol structure via a nucleophilic addition of an alcohol molecule with a o‐quinone is a key reaction for the high radical‐scavenging activity of protocatechuic acid esters in alcoholic solvents.     

NMR spectroscopic analysis of neferine and isoliensinine

Neferine and isoliensinine are the two major compositions of the Chinese medicine lotus plumule. They have extensive cardiovascular activity, such as antiarrhythmic, antithrombic and antihypertensive. In order to confirm the structures reported in the literature by explicit 1H and 13C assignments, we used a series of NMR experiments including 1H, 1H-COSY, HSQC and HMBC. The absolute configuration of neferine (C-1 and C-1') was determined as R and S and that of isoliensinine (C-1 and C-1') was determined as R and R.     

铱(Ⅲ)与2-(5-溴-2-吡啶偶氮)-5-二甲氨基苯胺的显色反应及其应用

研究了试剂2_(5_溴_2_吡啶偶氮 )_5_二甲氨基苯胺 (5_Br_PADMA)与铱 (Ⅲ )的显色反应 ;在 pH4.75～6.00的HAc -NaAc缓冲溶液中 ,铱 (Ⅲ )与5_Br_PADMA形成摩尔比为1∶2型稳定的红色络合物 ,在0.6mol/LH2SO4溶液中 ,其最大吸收波长为558nm ,表观摩尔吸光系数为5.1×104L/(mol·cm) ,铱 (Ⅲ )含量在0～0.8mg/L范围内符合比尔定律 ,采用加入适量EDTA的方法消除了Fe3 + 、Co2 + 、Ni2 + 等干扰离子 ,建立了在二元络合物体系中测定微量铱 (Ⅲ )的灵敏度高、选择性好、简便、稳定的分光光度法     

原油乳状液稳定性和破乳研究进展

本文从控制乳状液稳定性的一些因素－界面膜、界面张力、双电层、空间位阻、固体粒子、液晶、油相溶解度、连续相粘度等方面综述了有关乳状液稳定性的一些研究进展。对国内外有关原油乳状液的破乳研究也做了综述。同时，介绍了应用于乳状液稳定性研究的新的实验技术和仪器。     

Thermal decomposition of Mn(II) complex of nicotinamide

The complex Mn(Nica)₂Cl₂ (Nica=nicotinamide) was prepared, and its decomposition was studied by means of TG and DSC. The IR spectra of the products of thermal decomposition were examined at every stage. Kinetic analysis of the first stage of thermal decomposition was performed via the TG-DTG curves, and the kinetic parameters were obtained from analysis of the TG-DTG curves with integral and differential methods. The most probable kinetic function was suggested from a comparison of the kinetic parameters. Mathematical expressions were derived for the kinetic compensation effect.

---

Zusammenfassung Der Komplex Mn(Nica)₂Cl₂ (Nica steht für Nikotinamid) wurde hergestellt und seine Zersetzung mittels TG und DSC untersucht. Die thermisch zersetzten Substanzen jedes Schrittes wurden mittels IR-Spektren untersucht. Anhand der TG-DTG-Kurven erstellte man eine kinetische Analyse des ersten Schrittes der thermischen Zersetzung, die kinetischen Parameter wurden aus den TG-DTG-Kurven unter Einsatz von Integrations- und Differentialmethoden ermittelt. Durch Vergleich der kinetischen Parameter wurde die wahrscheinlichste kinetische Funktion vorgeschlagen. Mathematische Ausdrücke für den kinetischen Kompensationseffekt wurden erhalten.

     

产酸克氏杆菌1,3-丙二醇发酵液中2,3-丁二醇的定性和定量分析

产酸克氏杆菌(Klebsiella oxytoca)在厌氧和微好氧条件下均可以发酵甘油产生1,3-丙二醇。相对于厌氧发酵液,在微好氧发酵液的高效液相色谱图中出现两个未知物峰。对微好氧发酵液进行离心,脱盐和蒸馏处理,以两未知物质为主要成分的馏分通过气相色谱-质谱联机分析显示两种未知物质均为2,3-丁二醇,通过气相色谱和高效液相色谱分析确定两未知物质分别为meso-2,3-丁二醇和L-( )-2,3-丁二醇。建立了用HPLC法对meso-2,3-丁二醇和L-( )-2,3-丁二醇进行外标定量的测定方法,在标准品浓度100~1200mg/L范围内,meso-2,3-丁二醇线性方程为y=7×10-6x,r=0.9991;L-( )-2,3-丁二醇线性方程为y=7×10-6x,r=0.9998。在发酵液样品中meso-2,3-丁二醇的回收率为99.67%;相对标准偏差RSD为0.35%,L-( )-2,3-丁二醇的回收率为99.89%;相对标准偏差RSD为0.09%。     

表面活性剂浓度与表面张力-稀释倍数积分值的关系研究

比较了三阶段Hermit插值和二次多项式的表面张力-稀释倍数拟合曲线及其求积方式,得出由三阶段Hermit插值所得n 1个离散数据点的拟合曲线,及对其前n个离散数据点所在区间上进行求积较佳。在三阶段Hermit插值拟合及求积方式下,分析了十二烷基硫酸钠、十六烷基三甲基溴化铵、茶皂素和去菌体前后含鼠李糖脂发酵液溶液浓度与表面张力-稀释倍数积分值之间的线性回归方程F值和r值,结果显示:F值大小受积分区间、(生物)表面活性剂种类、溶液浓度与临界胶团浓度的比值大小及溶液中杂质的影响,但F值均大于F0.005。