Synthesis,in vitro $$\alpha $$-glucosidase inhibitory activity,and in silico study of ( E)-thiosemicarbazones and ( E)-2-(2-(arylmethylene)hydrazinyl)-4-arylthiazole derivatives

This study is focused on the identification of thiazole-based inhibitors for the \(\alpha \)-glucosidase enzyme. For that purpose, (E)-2-(2-(arylmethylene)hydrazinyl)-4-arylthiazole derivatives were synthesized in two steps and characterized by various spectroscopic techniques. All derivatives and intermediates were evaluated for their in vitro \(\alpha \)-glucosidase inhibitory activity. Thiosemicarbazones 20 and 35, and cyclized thiazole derivatives 2, 5–11, 13, 15, 21–24, 27–31, and 36–37 showed significant inhibitory potential in the range of \(\hbox {IC}_{50}=6.2\pm 0.19\)–\(43.6\pm 0.23~\upmu \hbox {M}\) as compared to standard acarbose (\(\hbox {IC}_{50}=37.7\pm 0.19~\upmu \hbox {M}\)). A molecular modeling study was carried out to understand the binding interactions of compounds with the active site of enzyme.     

Analysis of hydrogen bonding and weak interactions in the crystal structure of (E)-N-(4-ethylphenyl)-2-(4-hydroxybenzylidene)thiosemicarbazone: experimental and theoretical studies

Hydrogen-bonding interactions play an important role in the rational design of crystal systems with desirable architectures. The novel thiosemicarbazone derivative described herein, namely (E)-N-(4-ethylphenyl)-2-(4-hydroxybenzylidene)thiosemicarbazone, C₁₆H₁₇N₃OS, (I), was prepared and characterised by ¹H NMR, IR and single-crystal X-ray crystallography techniques. The compound is arranged in the lattice by O–H···S and N–H···S bonded polymeric ribbons that extend along the crystal b-axis, and the intermolecular N–H···S hydrogen bonds formed R2 2(8) ring motifs. More importantly, C–H···π interaction stabilises the supramolecular structure of (I). Hirshfeld surface and their associated two-dimensional fingerprint plot analyses are presented to illustrate the supramolecular connectivity in the solid state. The result shows that the short H···H contacts is dominated in the total Hirshfeld surface. As well as we report on n→π* interactions in thiosemicarbazone derivatives by using the reduced density gradient function and natural bond orbital analyses. Besides, molecular electrostatic potential (MEP) and frontier molecular orbital (FMO) analysis of the title compound are also investigated by theoretical calculations.     

Synthesis,crystal structure and antimicrobial activity of 2-((2-(4-(1H-1,2,4-triazol-1-yl)phenyl)quinazolin-4-yl)oxy)-N-phenylacetamide derivatives against phytopathogens

Molecular Diversity - A total of eighteen 2-((2-(4-(1H-1,2,4-triazol-1-yl)phenyl)quinazolin-4-yl)oxy)-N-phenylacetamide derivatives were designed and synthesized, via hybrid pharmacophore approach....     

4-[(E)-2-(3, 4-二甲氧基苯基)乙烯基]苯氧基乙酸乙酯的合成及其NMR研究

以对硝基甲苯、3, 4-二甲氧基苯甲醛为起始原料,经过缩合,还原,重氮化水解,亲核取代反应,最终合成了新的化合物4-[(E)-2-(3, 4-二甲氧基苯基)乙烯基]苯氧基乙酸乙酯,用¹H 和¹³C NMR及多种二维核磁共振谱确定了该化合物的结构,完成了¹H 和¹³C NMR的归属,给出了分子中各氢,碳原子的准确化学位移.     

(2R,5S)-N-间氟苄基-2,5-二甲基哌嗪的合成

以(2R,5S)-2,5-二甲基哌嗪为原料,经过成盐,单取代反应,用D-酉石酸对光学异构体的手性拆分,用氢氧化钠游离,最终合成(2R,5S)-N-间氟苄基-2,5-二甲基哌嗪,反应总收率为83％.该物质的合成未见文献报道,目标化合物用1H NMR,IR进行结构表征.     

Theoretical and experimental determination of the physicochemical properties of 2-(4-pyridyl)-5-phenyloxazole (4PyPO)

Studies have been made on 4PyPO, which represents a new class of water-soluble dye for quantum electronics. Quantum-chemical calculations indicate the most likely site of proton attachment to 4PyPO and explain the changes in the absorption and fluorescent spectra in acid media. The protonated form of 4PyPO fluoresces in neutral aqueous solution because of the substantial increase in probability of proton attachment in the S₁ state. Simulating the solvation in the calculation of the H-bonded complex improves the agreement between the theoretical and experimental results.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 48–52, August, 1987.We are indebted to V. Ya. Artyukhov for useful discussions.     

Synthesis of N-(4-bromo-2-trifluoromethylphenyl)-1-(2-fluorophenyl)-O,O-dialkyl-alpha-aminophosphonates under ultrasonic irradiation

Boron trifluoride diethyl etherate catalyzes the Mannich-type reaction of 2-trifluoromethyl-4-bromoaniline and O,O-dialkylphosphite with 2-fluorobenzoaldehyde under ultrasonic irradiation to synthesize the corresponding product alpha-aminophosphonate. The advantages of the procedure include short reaction period, high yield and simple working up. Their structures were clearly established by IR, (1)H NMR, (13)C NMR and elemental analysis. The bioassay tests showed that the title compounds exhibit moderate antitumor activity in vitro by MTT method.     

4-(4-氨基苯基)-3-吗啉酮的合成

4-(4-氨基苯基)-3-吗啉酮是合成利伐沙班的一个重要中间体,以吗啉酮为原料,利用Buchwald-Hartwig偶联反应制得4-苯基-3-吗啉酮,再经硝化,还原三步反应制备4-(4-氨基苯基)-3-吗啉酮。     

2-对二甲氨基苯基-5-氟-6-吗啉苯并咪唑的合成及其光谱学性质研究

合成了一种新的取代苯并咪唑化合物 ,2 对二甲氨基苯基 5 氟 6 吗啉苯并咪唑 ,采用紫外 可见光谱、荧光光谱及荧光寿命等方法探讨了溶液pH值对该化合物吸收光谱的影响及其与 β 环糊精的作用。结果表明 ,pH >7 0时 ,该化合物在溶液中主要以中性分子状态存在 ,当 3 8相似文献   

Synthesis,Optical Investigation and Biological Properties of Europium(III) Complexes with 2-(4-Chlorophenyl)-1-(2-Hydroxy-4-Methoxyphenyl)Ethan-1-one and Ancillary Ligands

Synthesis and photoluminescence behaviour of six novel europium complexes with novel β-hydroxyketone ligand, 2-(4-chlorophenyl)-1-(2-hydroxy-4-methoxyphenyl)ethan-1-one (CHME) and 2,2′-bipyridine (bipy) or neocuproine (neo) or 1,10-phenanthroline (phen) or 5,6-dimethyl-1,10-phenanthroline (dmphen) or bathophenanthroline (bathophen) were reported in solid state. The free ligand CHME and europium complexes, Eu(CHME)₃.2H₂O [1] Eu(CHME)₃.bipy [2], Eu(CHME)₃.neo [3], Eu(CHME)₃.phen [4], Eu(CHME)₃.dmphen [5] and Eu(CHME)₃.bathophen [6]were characterized by elemental analysis, FT-IR and ¹H-NMR. The photoluminescence emission spectra exhibited four characteristic peaks arising from the ⁵D₀ → ⁷F_J (J = 1–4) transitions of the europium ion in the solid state on monitoring excitation at λ_ex = 395 nm. The luminescence decay curves of these europium complexes possess single exponential behaviour indicating the presence of a single luminescent species and having only one site symmetry in the complexes. The luminescence quantum efficiency (η) and the experimental intensity parameters, Ω ₂ and Ω ₄ of europium complexes have also been calculated on the basis of emission spectra and luminescence decay curves. In addition, the antimicrobial and antioxidant activities were also studied of the investigated complexes.     

1-(4-硝基苯)-3-(2-吡嗪)-三氮烯的合成及与锌(Ⅱ)的显色反应

报道了1-（4-硝基苯）-3-（2-吡嗪）-三氮烯（NPPT）的合成及与锌（Ⅱ）的显色反应。在非离子表面活性剂TritonX-100存在下,于pH8.8的KCl,H3BO3-NaOH缓冲介质中,NPPT与锌（Ⅱ）形成4∶1的黄棕色络合物,在465nm处有一最大吸收,表观摩尔吸光系数为3.15×104L·mol-1.cm-1,10mL溶液中,锌（Ⅱ）量在0—0.56μg范围内符合比尔定律。方法用于葡萄糖酸锌口服溶液中微量锌的测定,测定结果与AAS法相符。     

Copper(I) Complexes of N-(2-{[(2E)-2-(4-Nitrobenzylidenyl)Hydrazinyl]Carbonyl}Phenyl)Benzamide and Triphenylphosphine: Synthesis,Characterization and Luminescence Properties

Copper(I) complexes of the formula [Cu(L)(PPh₃)₂]X (1–4) (X = Cl(1), ClO₄(2), BF₄(3) and PF₆(4)) [where L = N-(2-{[(2E)-2-(4-nitrobenzylidenyl)hydrazinyl]carbonyl}phenyl)benzamide; PPh₃ = triphenylphosphine] have been prepared by the condensation of N-[2-(hydrazinocarbonyl)phenyl]benzamide with 4-nitrobenzaldehyde followed by the reaction with CuCl, [Cu(MeCN)₄]ClO₄, [Cu(MeCN)₄]BF₄ and [Cu(MeCN)₄]PF₆ in presence of triphenylphosphine as a coligand. Complexes 1–4 were then characterized by elemental analyses, FTIR, UV-visible and ¹H NMR spectroscopy. Mononuclear copper(I) complexes 1–4 were formed with L in its keto form by involvement of azomethine nitrogen and the carbonyl oxygen along with two PPh₃ groups. A single crystal X-ray diffraction study of the representative complex [(Cu(L)(PPh₃)₂]CIO₄ (2) reveals a distorted tetrahedral geometry around Cu(I). Crystal data of (2): space group = C2/c, a = 42.8596 (9) Å, b = 14.6207 (3) Å, c = 36.4643 (7) Å, V = 20,653.7 (7) ų, Z = 16. Complexes 1–4 exhibit quasireversible redox behaviour corresponding to a Cu(I)/Cu(II) couple. All complexes show blue-green emission as a result of fluorescence from an intra-ligand charge transition (ILCT), ligand to ligand charge transfer transition (LLCT) or mixture of both. Significant increase in size of the counter anion shows marked effect on quantum efficiency and lifetime of the complexes in solution.     

Synthesis and phase transition studies on non-symmetric liquid crystal dimers: N-(4-(n-(4-(benzothiazol-2-yl)phenoxy)alkyloxy)-benzylidene)-4-chloroanilines

A new series of non-symmetric liquid crystal dimers N-(4-(n-(4-(benzothiazol-2-yl)phenoxy)alkyloxy)benzylidene)-4-chloroaniline containing benzothiazole and benzylideneimine units connected by a flexible alkyl spacer, –(CH₂) _n –, with n ranging from 4 to 12 in even parity have been prepared. All five members of this homologous series exhibit an enantiotropic nematic phase. The compounds with greater n of 8–12 exhibit both nematic and smectic phases upon cooling. A notable feature among this series is that for the member with n?=?10, the smectic–nematic transition is also present. The nematic–isotropic transition temperatures and associated entropy changes with respect to all compounds in this series exhibit a dramatic dependence on the length of the flexible spacer. A comparison of the transitional properties of this series with those of α-(4-benzylidenechloroaniline-4′-oxy)-ω-[4-(thiophene-2-carboxyl)benzylideneaniline-4′-oxy]alkanes reveals that replacing benzothiazole moiety at one side of the flexible alkyl spacer reduces the nematic–isotropic transition temperature.     

Polyethylene glycol (PEG-400) promoted one-pot,five-component synthesis of (E)-ethyl2-(2-((E)-2-(1-(4-methyl-2-(phenylamino)thiazol-5yl)ethylidene)hydrazinyl)-4-oxothiazol-5(4H)-ylidene)acetates

Molecular Diversity - A facile, inexpensive and eco-friendly synthesis of functionalised...     

类镓等电子序列ZrX—RhXV离子的4s^24p—4s^24d,4s^24p—4s4p^2,4s^24 …

本文对类镓等电子序列ＧａＩ－ＸｅＸＸＩＶ离子４ｓ＾２４ｐ、４ｓ＾２４ｐ、４ｓ＾２４ｄ、４ｓ４ｐ＾２、４ｐ＾３和４ｓ＾２５ｓ组态组级结果和组态相互作用了理论分析，找出沿等电子序列的变化规律。     

The theoretical studies on the two-photon absorption properties of symmetric l,4-bis{2-[4-(2-aryl)phenyl]vinyl}-2,5-bisdialkoxybenzenes

<正>On the level of the time-dependent hybrid density functional theory,the one- and two-photon absorption properties of a series of symmetric 4-bis{2-[4-(2-aryl) phenyl]vinyl}-2,5-bisdialkoxybenzenes are studied respectively utilizing the analytic response theory and the few-state model methods.The calculated results show that the planarity of the geometrical structure plays a great role in enhancing the linear and nonlinear optical abilities of the molecule.However the effect of the length of the chain linked to theπ-centre on the optical property is very little.For the investigated compounds,the A-π-A type charge-transfer molecules display more superior one- and two-photon absorption characteristics than the D-π-D type ones.Furthermore,the two-photon absorption results by use of few-state model are generally consistent with those by analytic response theory,demonstrating the reliability of the few-state model for evaluating the two-photon absorption cross section.The numerical simulations are in good agreement in tendency with the available experimental measurements.     

2-羟基-1-萘醛缩对氨基水杨酸希夫碱的合成、表征及性质

合成2-羟基-1-萘醛对氨基水杨酸新型水杨酸类希夫碱(HL),通过紫外吸收法、红外光谱法、元素分析法、高分辨质谱对其进行结构表征.利用荧光光谱法,采用Stern-Volmer方程、双对数回归曲线模型处理数据,得出不同温度下HL与牛血清白蛋白(BSA)的结合常数、结合位点数和相关热力学参数,所得热力学数据表明HL与BSA结合方式主要为疏水作用.