Design,Synthesis,and Biological Evaluation of 5H-Thiazolo[3,2-a]pyrimidine-6-carboxylic Acid Ethyl Ester Derivatives as a Novel Series of Acetylcholinesterase Inhibitors

Acetylcholinesterase inhibitors are the most frequently prescribed anti-Alzheimer＇s drugs. A series of 5H-thiazolo[3,2-a]pyrimidine-6-carboxylic acid ethyl ester derivatives as the novel acetylcholinesterase inhibitors was designed based on virtual screening methods. The target compounds were synthesized with Biginelli reaction and Hantzsch-type condensation of dihydropyrimidines with substituted phenacyl chlorides, and were characterized with elemental analysis, IR, MS, ^1H NMR, and ^13C NMR. The biological evaluation against human acetylcholinesterase in vitro indicated all the target compounds show more than 50% inhibition at 10μmol/L by means of the Ellman method. The results provide a starting point for the development of novel drugs to treat Alzheimer＇s disease and lay the foundation of searching for improved acetylcholinesterase inhibitors with the novel scaffolds.

Synthesis and Physicochemical Properties of L-(+)-a-(Positive Butyl)-Leucine Ethyl Ester Chiral Ionic Liquids

L-（＋）-α-（positive butyl）-leucine ethyl ester bromide chiral ionic liquid was synthesized by using microwave-assisted synthesis method and L-（＋）-α-（positive butyl）-leucine ethyl ester terafluoroborate and hexafluorophosphate chiral ionic liquids were synthesized by the anion exchange reaction. The structures were characterized by IR, ~1HNMR and structure optimization calculation. The results of studies on physicochemical properties show that they possess better thermal stability, solubility, bio-solubility and high conductivity. They can serve as effective reaction media as well as chiral catalysts. They are presently being investigated as dispersion agents in molecular imprinting ployer.

Synthesis, Crystal Structure and Inhibition of N-2-Thiophenesulfonyl-α-L-phenylalanine Ethyl Ester on K562 Cell Proliferation

The title compound N-2-thiophenesulfonyl-a-L-phenylalanine ethyl ester has been synthesized. Complete assignments were achieved by IR, MS, ^1H NMR and single-crystal X-ray diffraction analyses. Using MTT assay, the inhibitory rate of the title compound on K562 cells （chronic myeloid leukemic cells） was measured and the result of preliminary bioassay showed that the title compound possesses antiproliferation effects on K562 cells. In order to investigate the relationship between structure and activity of the target compound, we report its crystal structure and biological behavior in the present paper. Crystallographic data： C15H17NO4S2, Mr = 339.42, monoclinic, space group P21, flack = -0.15（12）, a = 5.7916（10）, b = 11.5078（19）, c = 12.924（2） A, β = 97.781（3）°, Z = 2, V = 853.4（2） A^3, De = 1.321 g/cm^3, F（000） = 356, -7≤h≤7, -10≤k≤14, -15 ≤ l≤15, R = 0.0628, wR = 0.1540 and μ（MoKa） = 0.327 mm^-1. The molecule comprises a benzene and a thiofuran rings, and the intramolecular N（1）-H（1A）…O（1） makes a five-membered ring of O（1）--C（6）-C（5）--N（1）--H（1A）.

Synthesis and Crystal Structure of 4-(4,6-Dimethoxylpyrimidin-2-yl)-3-thiourea Carboxylic Acid Ethyl Ester

4-（4,6-Dimethoxyl-pyrimidin-2-yl）-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at room temperature. The crystal structure was determined by X-ray diffraction analysis. Crystallographic data： C10H14N4O4S, M, = 286.31, monoclinic, space group C2/c with a = 2.5309（3）, b = 0.67682（6）, c = 1.74237（19） nm, β = 114.744（3）°, V= 2.7106（5） nm3, Dc = 1.403 g/cm3, p = 0.225 mm-1, F（000） = 1200, Z= 8, R= 0.0514 and wR= 0.1529.

Supercritical Synthesis of Ethyl Esters via Transesterification from Waste Cooking Oil Using a Co-Solvent

Biofuels became more promising alternative to the fossil fuels because of the depletion of fossil resources, renewability, environmental benefits, and energy security. Ethanolysis of waste cooking oil with hexane as co-solvent was carried out for the production of fatty acid ethyl ester (FAEE). This process reduced the severity of process parameters with high purity biodiesel yield. Process variables such as co-solvent ratio, ethanol to oil molar ratio, reaction temperature and reaction time were optimized. The maximum biodiesel yield of 88% was obtained at ethanol/oil molar ratio of 40:1, co-solvent (hexane) to oil ratio of 0.2% (v/v), reaction temperature of 300°C in 20 min of reaction time. Fatty acid ethyl ester (biodiesel) samples produced from this process were measured and evaluated using GC-MS analytical instrument. Thermo gravimetric analysis (TGA) was also performed to examine the thermal stability of waste cooking oil, ethyl esters and fuel blends. Fuel properties of ethyl esters were determined and compared with the ASTM standards for biodiesel, regular diesel and ethyl esters from different feedstock.

Synthesis and Characterization of 2-cetyl-3-20 keto acid(N-ethyl perfluorinated octyl sulfonamide) N-ethyl ester

2-Cetyl-3-20 keto acid（N-ethyl perfluorinated octyl sulfonamide） N-ethyl ester was synthesized by the reaction of N-ethyl-N-hydroxyethyl perfluorinated octyl sulfonamide and alky ketene dimer. The experimental results show that the yield of products can be 89% when the molar ratio of perfluorinated octyl sulfonamide to ketene dimer is 1 ： 1.1 and the reaction lasts about four hours at 80 ℃. The structure of the product was characterized by FTIR and ^1HNMR. The product can dissolve in polar solvents such as NMP, DMAC, THF, DMSO, CHCl3, and 10% weight-loss temperature measured by TGA is 202℃.

An Alternative Synthesis and Crystal Structure Characterization of Nutrient Fortifier N-(1-(Phenylacetyl)-L-prolyl) Glycine Ethyl Ester

A nutritional fortifier N-(1-(phenylacetyl)-L-prolyl)glycine ethyl ester(4)was successfully synthesized through two synthetic schemes and characterized by IR,^1H-NMR,^13C-NMR,elemental analysis and X-ray single-crystal diffraction.The intermediate N-phenylacetyl-L-proline(2)was synthesized by the solid-liquid reaction of L-proline and phenylacetyl chloride directly.Compound 2(C13 H15 NO3,Mr=233.26)belongs to the orthorhombic system,space group P212121 with a=8.9468(3),b=9.3190(3),c=14.0453(4)A,V=1171.03(6)A^3,Z=4,Dc=1.323 g/cm^3,μ=0.773 mm^-1,F(000)=496.0,the final R=0.0313 and wR=0.0797 for all data.Compound 4(C17 H22 N2 O4,Mr=318.36)is of orthorhombic system,space group P212121 with a=6.5831(2),b=8.5536(2),c=28.9138(9)A,V=1628.11(8)A^3,Z=4,Dc=1.299 g/cm3,μ=0.763 mm-1,F(000)=680.0,the final R=0.0353 and wR=0.0816 for all data.

HeI photoelectron spectroscopic (PES) studies of the electronic structure in ω-heterocycle a-cyano polyenic ethyl ester compounds

HeI photoelectron spectra of w-heterocycle a-cyano polyenic ethyl ester compounds (1-6) have been given in this paper. Assignment of the spectra is also done with the aid of HeI photoelectron spectroscopic (PES) results of smaller molecules which have similar atomic group to the molecules studied, and the aid of MNDO molecules orbital calculations. The lowest PES experimental ionization potentials (IPs in eV) of different molecules reduce gradually with the increasing number of ethylenic group. The -CO2C2H5 group can be only considered as a substituent.

Hop-induced formation of ethyl esters in dry-hopped beer

Fruity smelling esters play an important role for the aroma of hops and beer and they have been characterized as key aroma compounds in different hop varieties.Studies on the transfer of hop-derived compounds into beer during dry-hopping showed calculated transfer rates of different ethyl esters far above 100%,leading to the assumption that these esters must be newly formed.To investigate this formation,dry-hopping was imitated in water to eliminate the influence of the beer matrix on the formation of these odorants.Thereby,the formation of ethyl esters of 2-methylbutanoic acid,3-methylbutanoic acid,and methylpropanoic acid,induced by the addition of hops,was shown.Different approaches inhibiting enzyme activities and experiments with different hop extracts might lead to the assumption that enzymes are involved in the formation of these esters,beside possible transesterification.

Synthesis of biodegradable poly (methylparaben/glycine ethyl ester) phosphazene and further research of its degradation in vitro

Polydichlorophosphazene(PDCP)was synthesized from PCl5 and NH4Cl via a one-pot approach,and then further reacted with glycine ethyl ester and methylparaben via a two-step nucleophilic substitution approach to give poly(methylparaben/glycine ethyl ester)phosphazene(PMGP),which was a kind of mix-substituted biodegradable polymer.NMR and FT-IR were used to characterize its structure.A series of experiments were conducted to study the effects of the ratio of methylparaben to glycine ethyl ester and the experimental conditions to the degradability of PMGP samples.The degradability of PMGP can be adjusted by altering the ratio of methylparaben to glycine ethyl ester easily.

Iodine-catalyzed Efficient Synthesis of β-Keto Esters from Aldehydes and Ethyl Diazoacetate Under Solvent-free Conditions

An efficient procedure for the synthesis ofβ-keto esters from the reaction of aldehydes and ethyl diazoacetate catalyzed by iodine at room temperature under solvent-free conditions has been described. The catalytic procedure has the advantages of easily available catalyst, mild reaction conditions, high yields, and easy work-up.

Extraction Separation of Scandium，Iron and Lutetium with Isopropyl Phosphonic Acid Mono（1－hexyl－4－ethyl）OctylEster

The extraction and stripping of scandium from its sulfate solutions by isopropyl phosphonic acid mono (1-hexyl-4-ethyl) octyl ester (PT-2, HL) diluted with n-hexane are reported. A high efficiency of separation between scandium, iron and lutetium can be achieved by controlling aqueous acidity. Different mechanisms of Sc3+ with PT-2 in various acid range have been proposed.At lower aqueous acidity, it is a cation exchange reaction, while at higher acidity. a solvation reaction was ascertained. Its IR and NMR spectra have been discussed. The effect of temperature on extraction of Sc3+ was observed and thermodynamic functions were calculated.

Polyclonal antibody-catalyzed hydrolysis of naproxen ethyl ester

In 1986 two monumental reports appearing on antibody catalysis which combined the tremendous diversity of antibody with catalytic power of enzyme opened new horizons of chemical and immunogical fields. Since then, a large number of catalytic antibodies have been prepared successively by using designed organic molecules as haptens conjugated to carrier proteins to immunize the animals and screening out the desired monoclonal antibodies through hybridoma technology. So far more than fifty examples

Enantioselective hydrolysis of naproxen ethyl ester catalyzed by polyclonal antibodies

BASED on the hypothesis of Pauling on enzyme action that free energy difference between theground and transition state is reduced by the specific binding of active center of enzyme to theintermediate,a large number of antibodies with catalytic power have been obtained successive-

月桂酰精氨酸乙酯的不同应用形式对干酪贮藏期间品质变化的影响

研究构建月桂酰精氨酸乙酯的水溶液、乳状液、固体脂质粒、壳聚糖可食性涂膜等不同形式应用于干酪保藏,通过对贮藏过程中干酪的菌落总数、色差、质构和感官进行测定和分析,评估最适合干酪贮藏的应用形式。实验结果表明,月桂酰精氨酸乙酯能够有效抑制干酪表面英诺克李斯特菌的生长,延长贮藏时间。在4℃贮藏20 d后,对照组菌落数增加了7.02 log CFU/g,月桂酰精氨酸乙酯能有效抑制李斯特菌生长,小尺寸颗粒乳状液处理组抑菌效果最好,菌落数仅增加了2.44 log CFU/g。在色差、质构及感官分析中,发现月桂酰精氨酸乙酯并不会影响干酪的品质。作为新型保鲜剂,月桂酰精氨酸乙酯在干酪贮藏中具有广阔的应用前景,小尺寸颗粒乳状液具有更好的保藏效果。

血浆脂肪酸乙酯与酒精性急性胰腺炎炎症和疾病严重程度的相关性研究

目的分析血浆脂肪酸乙酯(FAEE)与酒精性急性胰腺炎(AAP)炎症和疾病严重程度的相关性。方法回顾性分析2017年1月至2022年1月该院收治的227例AAP患者及213例非酒精性急性胰腺炎(AP)组患者数据。根据Bathazar计算机断层扫描严重指数将AAP患者的疾病严重程度分为轻度、中度、重度。通过气相色谱分析患者血浆FAEE和游离脂肪酸(NEFA)水平。结果AAP组患者血浆FAEE(P<0.001)和NEFA(P=0.019)水平相较于非酒精性AP组更高。然而,经受试者工作特征(ROC)曲线分析,血浆FAEE对鉴别诊断AAP与非酒精性AP有良好效能,曲线下面积(AUC)为0.926(95%CI:0.901~0.951)。中度[158.77(127.01~230.55)nmol/L]和重度[274.49(208.32~309.31)nmol/L]AAP患者血浆FAEE水平高于轻度患者[126.15(84.37~166.52)nmol/L],而且重度患者较中度患者更高(H=64.069,P<0.001)。血浆FAEE水平>146.61 nmol/L为重度AAP发生的危险因素(P<0.05),且其对重度AAP有较好的预测价值,AUC为0.786(95%CI:0.705~0.867)。Spearman秩相关分析结果显示,AAP患者血浆FAEE水平与白细胞介素(IL)-1β、IL-6及NEFA水平呈正相关(rS=0.298、0.475、0.302,均P<0.001)。结论血浆FAEE有可能成为AAP鉴别诊断和预测疾病严重程度的潜在生物标志物。

叉枝蒿对粘虫杀虫活性成分及作用机制研究

【目的】探究叉枝蒿对粘虫的杀虫活性及杀虫机制,为粘虫的高效绿色防控提供理论依据。【方法】采用浸虫浸叶法测定10种蒿属植物提取物及叉枝蒿不同极性4部分萃取物对粘虫3龄幼虫的杀虫活性;分别采用小叶碟添加法、浸叶法和浸虫法确定叉枝蒿石油醚萃取物对粘虫的主要杀虫方式;通过浸虫法测定叉枝蒿石油醚萃取物、馏分及主要成分对粘虫3龄幼虫的触杀活性。叉枝蒿石油醚萃取物经柱层析分离及气相色谱—质谱分析,确定其活性成分,并测定活性成分对粘虫体内4种酶活力的影响。【结果】叉枝蒿石油醚萃取物对粘虫3龄幼虫的触杀活性最好,处理第7 d时对粘虫的致死中浓度(LC_(50))为6.85 mg/mL。经硅胶柱色谱分离,从叉枝蒿石油醚萃取物中得到21个馏分,其中馏分8表现出最好的触杀活性;气相色谱—质谱分析结果显示,馏分8的主要化合物为棕榈酸乙酯(49.57%)、十三烷(14.55%)、硬脂酸乙酯(4.86%)和壬烷(4.74%),4种化合物中以棕榈酸乙酯的触杀活性最好,处理后第7 d时对粘虫的LC_(50)为1.82 mg/mL。棕榈酸乙酯LC_(50)处理粘虫第7 d时扫描电镜显示,粘虫表皮蜡质层颗粒排列疏松,间隙增大。棕榈酸乙酯LC_(50)处理粘虫1、3、5和7 d时,粘虫体内乙酰胆碱酯酶(AChE)和Na^(+)-K^(+)-ATP酶随时间的推移表现出抑制作用,羧酸酯酶(CarE)表现出先激活后抑制作用,过氧化氢酶(CAT)表现出先抑制后激活作用。【结论】叉枝蒿对粘虫具有良好的杀虫活性。叉枝蒿石油醚萃取物中的棕榈酸乙酯对粘虫的触杀活性最好,可作为粘虫生物防治的潜力化合物进行开发利用。

A new caffeic ester from Incarvillea mairei var.granditlora (Wehrhahn) Grierson

新 cafferic 酉旨，(+)-2-(1-hydroxyl-4-oxocyclohexyl) 乙醇 caffeate，从 Incarvillea mairei var 的整个植物的 80% 乙醇摘录被孤立。granditlora (Wehrhahn ) Grierson。混合物的结构被分光镜的方法建立。

Synthesis, Spectroscopic and Crystal Structure Studies on Ethyl 5,7-Dimethyl Coumarin-4-Acetate

Ethyl ester of 5,7-dimethyl coumarin-4-acetic acid has been synthesized from 3,5-Xylenol in a two step sequence of reaction involving Pechmann cyclisation and acid catalyzed esterification. The title compound 2 crystallizes in Monoclinic form, space group P 1 21/c 1, with a = 8.6248(4) ?, b = 18.9103(8) , c = 8.4204(4)?, β = 101.241(2)?, V = 1347.00(11) ?, D cal = 1.283 Mg/cm3, Z = 4. The molecule is stabilized by intermolecular C-H … O bonds.

Lipase-Catalyzed Synthesis and Characterization of 6-O-(11-Dodecenoic)-Glucose Ester in Ionic Liquids

Novozym-435 Lipase-catalyzed transesterification of glucose with 11-dodecenoic ethyl ester in ionic liquids was investigated. The effect of substrate ratio, lipase content, and temperature on the activity and stability of lipase was also studied. The highest yield of sugar ester was obtained in 1-buty-3-methyl imidazolium tetrafluoroborate [Bmim][BF4] under such conditions as the reaction temperature of 55℃, the enzyme concentration of 20 mg/mL, the mole ratio of glucose/11-dodecenoic ethyl ester of 1:2, the water content of the system of 2%, Lipase Novozym-435 can use repeatedly 7 times. The structure of production was characterized by FTIR, HPLC, MS and NMR. The results show that the production is 6-O-(11-dodecenoic)-glucose ester.