TLC Identification and Extraction Process of Rubiasin-1-methyl Ether from Yao Medicine Chuanlianzhu

[Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopted for TLC.Petroleum ether(60-90℃)-chloroform-methanol-water(7:15:3:1)was used as the developing solvent and inspected under ultraviolet lamp(365 nm).The content was determined by Inertsil ODS-3 C 18 column(4.60 mm×250 mm,5μm),mobile phase:acetonitrile-0.2%phosphoric acid gradient elution,detection wavelength 277 nm,flow rate 1.0 mL/min,column temperature 30℃,injection volume 10μL.[Results]The spots of 10 Chuanlianzhu samples from different origins showed the same color at the same position as the control,and the spots were clear and specific.The injection volume of rubiadin-1-methyl ether showed a good linear relationship in the range of 2.90-145μg(R=0.9996).The average recovery rate of rubiadin-1-methyl ether in the low,medium and high dose groups of Yao Medicine Chuanlianzhu was 98.72%,and RSD=1.78%.[Conclusions]This method can effectively identify Yao Medicine Chuanlianzhu medicinal materials and accurately determine the content of rubiadin-1-methyl ether in the medicinal materials.It provides a scientific basis for the development and utilization of Yao Medicine Chuanlianzhu medicinal resources.

甲基嘧啶磷的绿色合成研究

以嘧啶醇和碳酸钾水溶液在有机溶剂中反应减压脱水,生成嘧啶醇钾盐与甲基氯化物进行缩合反应,经过滤、减压浓缩得到甲基嘧啶磷。优化的反应条件为:以甲苯为溶剂,n(嘧啶醇)∶n(碳酸钾)=1.0∶2.0,嘧啶醇钾盐含水量<0.1%,反应温度30~40℃,反应时间6 h。优化条件下,甲基嘧啶磷纯度98.5%,收率92.6%,该工艺转化率高、收率高、三废少,符合绿色环保生产理念,具有工业化应用前景。

MONOMER REACTIVITY RATIO AND THERMAL PERFORMANCE OFα-METHYL STYRENE AND GLYCIDYL METHACRYLATE COPOLYMERS

Synthesis and characterization of the copolymers （PAG） of α-methyl styrene （AMS） and glycidyl methacrylate （GMA） are presented. The copolymers of PAG were characterized by gel permeation chromatography （GPC）, Fourier transform infrared spectroscopy （FTIR）, nuclear magnetic resonance （^1H-NMR） and thermogravimetery （TG）. Based on the copolymer compositions determined by ^1H-NMR, the reactivity ratios of AMS and GMA were found to be 0.105 ± 0.012 and 0.883 ± 0.046 respectively by Kelen-Tudos method. TG revealed that thermal stability of the copolymers decreased with increasing the AMS content in the copolymers, which indicated that the degradation was mainly caused by the chain scission of AMS-containing structures. Under heating, the copolymers depolymerize at their weak bonds and form chain radicals, which could further initiate other chemical reactions.

Characterization ofanovel deep-seamicrobial esterase EstC 10 and its use in the generation o f(R)-methyl 2-chloropropionate

A novel esterase Est C10 from B acillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of Est C10 was characterized. At present, the reports about the kinetic resolution of racemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase Est C10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate( R)-methyl 2-chloropropionate with high enantiomeric excess(>99%) after the optimization of process parameters such as p H, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration(80 mmol/L) of esterase Est C10 was higher than the kinetic resolution of another esterase, Est12-7(50 mmol/L). The novel microbial esterase Est C10 identified from the deep sea was a promising green biocatalyst in the generation of( R)-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.

Microwave-assisted synthesis of new N^4-[bi-(4-fluorophenyl)-methyl]-piperazine thiosemicarbazones under solvent-free conditions

Six new N4-[bi-（4-fluorophenyl）-methyl]-piperazine thiosemicarbazones 3a-f have been prepared starting from [bi-（4-fluorophenyl）-methyl]-piperazine in solvent-free condition under microwave irradiation with excellent yields. Their structures have been determined by elemental analysis, IR, MS and 1H NMR data.

Controlled Self-assembly of Two Coordination Polymers via subtly Varying Bis(2-methyl imidazole) Ligands:from 3-Connected(6,3) Net to 4-Connected sql Net

Two coordination polymers constructed from 3,4-thiophenedicarboxylic acid and bis（2-methyl imidazole） ligands, namely, {[Cd2（tdc）2（bip）2]·7H20}n （1） and [Cd（tdc）（bib）]n （2） （Hgtdc = 3,4-thiophenedicarboxylic acid, bip = 1,3-bis-（imidazol-2-methyl）propane and bib = 1,4-bis（imidazol-2-methyl）butane）, have been synthesized and structurally characterized by single-crystal X-ray diffraction. Structural analyses reveal that 1 exhibits a two-dimensional （2D） layered network with 3-connected （6,3） topology, which is further connected into a three- dimensional （3D） supramolecular structure by intermolecular hydrogen bonds. However, 2 features a 2D network which can be rationalized as a 4-connected sql net. The results indicate the subtle difference of auxiliary bis（imidazol-2-methyl） ligands may lead to diverse architectures. Moreover, they exhibit luminescence emission in the solid state at room temperature.

Urinary Concentrations of Hydroxyproline and 3-Methyl Histidine in Postpartum Cow

The urinary concentrations of hydroxyproline (HYPRO)and 3 -methyl histidine (3 - MEHIS) were de- termined in 16 Chinese-Holstein cows. The objectives of the experiment were to find out thhe relationship between collagen and myosin ddegradation and uterine involution in the postpartum cow. The results in the experiment showed that the mean concentrations of HYPRO and 3-MEHIS were 138.32±22.99 and 37.09 ±3.90 nmol·mL-1,respectively,for the cows during the days between 60-90 postpartum,and for the cows immediately after calving the concentrations of HYPRO and 3 -MEHIS reduced from 284.30 and 65.48 nmol ·mL-1 on the day one after calving to the normal level of 109.18 and 33.51 nmol·mL^-1 on the day 50 post- partum,respectively. There was a good correlation between the urinary concentrations of both HYPRO and 3 -MEHIS and the diameters of the involuting uterus (r = 0. 79).

Theoretical Study on the Reaction Mechanism of o-Aminophenol, Acetic Acid and Phosphorus Oxytrichloride One-pot to Form 2-Methyl Benzoxazole

The reaction mechanism of o-aminophenol, acetic acid and phosphorus oxytrichloride in one-pot to form 2-methyl benzoxazole was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the GGA/PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Two possible reaction pathways were investigated in this study. The result indicates that the reaction Re→TS1→IM1→TSA2→IMA2→TSA3→IMA3→TSA4→IMA4→TSA5→P2 is the main pathway, the activation energy of which is the lowest. Re→TS1→IM1 is the rate-limiting step, with the activation energy being 221.54 kJ·mol;and the reaction heat being 10.06 kJ·mol;. The dominant product predicted theoretically is in agreement with the experiment results.

Interaction of N-(2-Methyl Thio Phenyl)-2-Hydroxy-1-Naphthaldimine with Tin Dioxide Nanoparticles: A Spectroscopic Approach

The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. SnO2 NPs are found to quench the intrinsic fluorescence of NMTHN via static and dynamic quenching. The deviation from linearity in the Stern-Volmer plot has been observed.

Comparison of HPLC-DAD and GC-FID Methods for Determination of 6-Methyl Coumarin in Cosmetics

The methods of determination of 6-methyl coumarin in cosmetics by HPLC-DAD and GC-FID were compared. The positive samples were confirmed by GC-MS. Methanol was used to extract 6-methyl coumarin from cosmetics. The chromatographic conditions of the two methods were optimized and the samples were determined. The recovery, precision, correlation coefficient, detection limit and quantitative limit of the two methods were compared. The results showed that the linear relationship between the two methods was good. The percentage recovery of standard addition by HPLC-DAD was 92.20%~102.80%, by RSD was 0.77%~2.00%;the detection limit was 0.05 mg/kg, the quantitative limit was 0.17 mg/kg. The percentage recovery of standard addition by GC-FID was 97.30%~103.28%, by RSD was 0.47%~4.87%;the detection limit was 1.3 mg/kg, the quantitative limit was 5.0 mg/kg. The detection limit by HPLC-DAD was lower and more sensitive than that by GC-FID , which also shows that HPLC-DAD has more advantages for the detection of low content samples.

甲基嘧啶磷原药中残留溶剂气相色谱分析

建立一种加相对校正因子的同时测定甲基嘧啶磷原药中残留溶剂甲醇、甲基异丁基甲酮和甲苯含量的气相色谱内标法。选用DB-17毛细管柱(15 m×0.25 mm,0.5μm),在程序升温条件下,对试样中甲基嘧啶磷和各待测组分进行有效分离,通过测定甲基嘧啶磷的校正因子和各溶剂相对于甲基嘧啶磷的相对校正因子,进行试样中残留溶剂的同时定量检测。方法中甲醇、甲基异丁基甲酮和甲苯的线性相关系数分别为0.99998、0.99996和0.99996,标准偏差为0.00089、0.012和0.00075,相对标准偏差为0.99%、0.62%和1.19%,平均添加回收率分别为99.07%、100.58%和100.92%。加相对校正因子的气相色谱内标法简单快速准确,适用于甲基嘧啶磷原药中残留溶剂的日常分析。

Effects of Garcinia kola “Bitter Kola” Powder on Sex Reversal, Survival and Growth Performance of Tilapia (Oreochromis niloticus L.)

This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola “Bitter kola” powder to obtain Oreochromis niloticus male sex populations. 1800 fry of average size between 0.01 and 0.02 g were distributed in 12 aboveground tanks of 1 m3 each at a rate of 150 individuals/tank, following 6 duplicate treatments. The negative (B1 and B2) and positive (B3 and B4) control diets, to which between 0 and 60 mg/kg of 17alpha-methyl testosterone had been added respectively, were mixed with industrial feed containing 40% protein;the tank diets (B5 and B6), (B7 and B8), (B9 and B10) and (B11 and B12) contained 10 g, 20 g, 30 g and 40 g of Garcinia kola powder respectively for 1 kg of industrial feed con-taining 40% protein. These different treatments resulted in high proportions of males in the order of 97.03%;98.09% for the hormone and proportions of 94.03%;93.26% for 20 g of Garcinia kola extracts. In terms of weight growth, the best average weights for the hormone and Garcinia kola were 0.896 g and 0.980 g respectively. With regard to fish survival, the following results were recorded: 95.53% and 94.56% respectively for additions of 20 g and 30 g of Garcinia kola extracts to the feed supplied to the fish. On the other hand, a significant difference in the mortality rate of 35% and 5% respectively for the conventional hormone and 20 g of Garcinia kola extracts was observed. To conclude the study, it is recommended that further studies be carried out to determine the quality of the flesh, their life stages and the profile of the amino acids present in their proteins.

Base-controlled NHC-Ru-catalyzed transfer hydrogenation andα-methylation/transfer hydrogenation of ketones using methanol

Herein,we report the NHC-Ru catalyst system that realizes the chemo-selective transformation of ketones with methanol.By simply changing the base,a broad range of structurally diverse ketones,could be selectively and efficiently converted to the correspondingβ-methylated secondary alcohols or secondary alcohols.Remarkably,this catalytic system was very effective for the synthesis of bio-related molecules and deuterated alcohols,as well as the three-component coupling between methyl ketones,primary alcohols,and methanol.The reaction mechanism was further revealed by experiment and DFT mechanistic investigations.

电催化氧化降解甲基嘧啶磷废水的实验研究

以铅合金板作阳极、不锈钢板为阴极,对甲基嘧啶磷生产废水的COD进行电催化氧化去除,研究了初始pH、电流密度和反应时间对去除效果的影响及电催化氧化条件下甲基嘧啶磷的降解机理。研究结果表明,在初始pH为7、电流密度为0.020 A/cm2、反应时间4 h时,废水中的COD由原来约100 000 mg/L降至约30 000 mg/L,去除率近70%,颜色也由棕红色达到近乎无色。

环保型甲基嘧啶磷纳米农药制剂的光催化降解

于甲基嘧啶磷农药中引入纳米TiO2、用十二烷基磺酸钠（SDS）改性的纳米TiO2和原位生成的纳米TiO2光催化剂,制成3种光降解源纳米农药制剂。它们在黑暗中能稳定存放,在紫外光和太阳光下3种纳米农药制剂的分解率显著提高。在太阳光下3 d,3种纳米农药制剂中甲基嘧啶磷分解率分别为69.00%、90.55%和51.90%,紫外光下3 h分解率分别是95.00%、99.5%和77.62%,而对照样纯农药在相同条件下分解率分别为9.1%和6.9%,改性纳米TiO2的制剂光催化活性最好。纳米农药制剂经粒度测试仪和扫描电镜分析,粒径～93nm,在黑暗中冷、热贮存7～14 d不分层,分解率小于1.4%。

3种生物源物质及甲基嘧啶硫磷对3种储粮害虫的毒力比较

采用滤纸药膜法研究了多杀菌素原药、阿维菌素精粉、蛇床子素粉剂对玉米象、谷蠹和锯谷盗的毒力,并与甲基嘧啶硫磷进行了毒力比较.结果表明:多杀菌素原药、阿维菌素精粉、蛇床子素粉剂和甲基嘧啶硫磷水乳剂对玉米象的LD50值分别为125.092μg/cm2、1 801.386μg/cm2、0.051μg/cm2和0.274μg/cm2,对谷蠹的LD50值分别为9.565μg/cm2、14.549μg/cm2、0.041μg/cm2和0.706μg/cm2,对锯谷盗的LD50值分别为24.557μg/cm2、55.501μg/cm2、0.050μg/cm2和0.185μg/cm2;多杀菌素和阿维菌素对3种害虫的毒力相当,多杀菌素和阿维菌素对3种害虫的毒力均小于甲基嘧啶硫磷,蛇床子素粉剂对3种害虫的毒力均高于甲基嘧啶硫磷至少3倍,且对谷蠹的毒力是甲基嘧啶硫磷的17倍多.

3种贮烟保护剂对取食不同食料烟草甲的生物活性

测定了甲基嘧啶磷、四溴菊酯、DDVP3种保护剂对面粉、烤烟饲养的烟草甲的室内触杀毒力。结果表明:3种保护剂对烟草甲触杀活性的大小依次为:四溴菊酯>甲基嘧啶磷>DDVP;不同食料对烟草甲幼虫的药剂敏感性也产生变化。

黄粉虫防治药剂的筛选研究

黄粉虫为蔺草制品的重要仓储害虫之一,对其防治研究具有重要意义。本文采用点滴法测定了几种杀虫剂对黄粉虫4龄幼虫的室内毒力。结果表明,溴氰菊酯对黄粉虫的毒力最高,其LC50值为9.23μg/mL;其次为甲基嘧啶磷,其LC50值为9.54μg/mL;进一步测定了溴氰菊酯与甲基嘧啶磷对试虫的混合毒力。结果表明,溴∶甲(1∶6)配比增效作用最明显,其CTC为137.5,LC50值为7.34μg/mL。因此,该配比值得进一步室内制剂加工研究以防治黄粉虫为害。

2种杀虫剂对白纹伊蚊杀灭效果研究

目的 了解 2种杀虫剂对现场白纹伊蚊的杀灭效果。方法 采用超低容量喷雾器喷洒。结果 甲基嘧啶磷喷洒处理 1d后RPI值为 6 85 ,灭得优处理 4h后RPI值为 0 ,1d后RPI值为 2 2 14 ,呈现良好快速杀灭作用 ,灭得优持效时间较甲基嘧啶磷长。 2种杀虫剂对白纹伊蚊幼虫的孳生地具有良好的控制作用 ,经趋势检验 ,两种杀虫剂的P值均小于 0 0 1,表明幼虫孳生阳性率随时间逐渐降低 ,效果显著。 2种杀虫剂喷洒处理 2 4h后 ,笼内白纹伊蚊校正死亡率均大于 99% ,说明白纹伊蚊对 2种杀虫剂都非常敏感。结论 2种杀虫剂对白纹伊蚊具有良好的速杀和一定的持效作用。

10%硫氟肟醚·甲基嘧啶磷微囊悬浮剂的制备及其药效实验

采用界面聚合法,以甲苯-2,4-二异氰酸酯为囊材,制备了硫氟肟醚·甲基嘧啶磷微囊悬浮剂。利用激光粒度分析仪、透射电镜和液相色谱对制备的微囊悬浮剂粒子进行了表征,室内药效实验考察了其对玉米象的活性。结果表明：10%硫氟肟醚·甲基嘧啶磷微囊粒径约0.10~0.35μm,且分布较为均匀;具有较高的包裹率和载药量,硫氟肟醚的包裹率为90.34%,甲基嘧啶磷包裹率为90.92%;热贮和低温稳定性实验结果表明微囊悬浮剂具有良好的热贮和低温稳定性。室内药效实验表明硫氟肟醚·甲基嘧啶磷微囊悬浮剂对储粮害虫的有很好的活性。界面聚合法制备的硫氟肟醚·甲基嘧啶磷微囊悬浮剂环境友好,持效期明显延长,适于储粮害虫的防治。