Synthesis of new pyrimidine-containing compounds: 5-(2-(alkylamino)-1,3-dioxo-2,3-dihydro-1H-inden-2-yl)-6-hydroxypyrimidine-2,4(1H,3H)-dione derivatives

Molecular Diversity - In this study, the one-pot reaction between primary amines, 1,1-bis-(methylthio)-2-nitroethene, ninhydrin, and barbituric acid as an enolizable C–H-activated compound...     

FTIR and 1H NMR Spectral Study of 3-(Substituted Benzamido)-5,6,7,8-Tetrahydro-5,8-methanoiso-quinolines And Related Compounds

The title benzamide derivatives were synthesized. FTIR spectra of the benzamides having substituents p-NH₂, p-OCH₃, p-CH₃ 3, p-F, H 5,p-CI, p-CF₃, p-CN, p-NO₂ 9 and m-Cl 10 and their related compounds were measured in dilute n-heptane, CCl₄, CHCl₃ and CH₂Cl₂ solutions. ¹H NMR spectra of the benzamides were also measured in CDCl₃ solution. Substituent effects on these spectra were investigated. The results were theoretically considered together with CNDO/2 calculation ones. Conformational analysis of 5 was carried out by the AMl method, and the results were compared with the X-ray structural data of 3, 5, 9 and 10. The intermolecular hydrogen bondings in crystals of the benzamides were examined based on the frequency shifts of their C=0 stretching vibration bands.     

Fluorescence of 5-hydroxy-6-methyl-(1-thietanyl-3)-pyrimidine-2,4(1 H,3 H)-dione at the transition with the second singlet-excited S 2 level to the ground level in acetonitrile solutions

The influence of the excitation wavelength on the fluorescence spectra of 5-hydroxy-6-methyl-(1-thietanyl-3)pyrimidine-2,4(1H,3H)-dione (TOMU) in acetonitrile solutions has been studied. It is found that, upon excitation of the singlet S ₂ state of TOMU luminescence, occurs from not only the first excited S ₁ level (??_max. = 350 nm, quantum yield ??(S ₁ ?? S ₀) = (4.5 ± 0.5) × 10^?3), but also at the transition from the second S ₂ level to the ground level (??_max = 305 nm, ??(S ₂ ?? S ₀) = (1.0 ± 0.1) × 10^?3).     

The discovery of 3-(1-aminoethylidene)quinoline-2, 4(1H,3H)-dione derivatives as novel PSII electron transport inhibitors

Based on the structures of the 4-hydroxyphenylpyruvate dioxygenase inhibitor mesotrione and natural product fischerellin A, a series of imine derivatives of ( $E$ )-3-acyl-quinoline-2,4(1H,3H)-dione (6, 12 and 16) were designed, synthesized and systematically evaluated for their herbicidal activity. The bioassay results indicated that most of the synthesized compounds displayed good to excellent herbicidal activity, of which 6e, 6g, 6h, 6q and 6t exhibited more than 50 % inhibition against Brassica napus L., Amaranthus retroflexu or Digitaria adscendens at a dosage of $94\,\hbox {g}\,\hbox {ha}^{-1}$ or lower. The symptom of injured leaves in vivo, the high Hill reaction inhibitory activity of 6h in vitro ( $\hbox {IC}_{50}\,0.1\, \upmu \hbox {g}\,\hbox {mL}^{-1})$ and the computer-based binding model of compound 6h with D1 protein in photosystem II (PSII) reaction centre suggest this novel structure to likely be a new type of PSII electron transport inhibitor. Thus, we have found a novel type of diketone enamine structure targeted at the PSII reaction centre.     

1H NMR确证6-氟-5(或7)-氯-3-苯基-4-(1H)-喹啉酮衍生物的结构

作者合成了6-氟-3-(取代)苯基-4-(¹H)-喹啉酮的5-氯衍生物与7-氯衍生物,二者极性差异小,难于分离,以混合物形式存在.所合成的化合物均未见文献报道,本文通过¹H NMR上的化学位移、积分面积以及偶合常数确证了混合物中两组份的结构.     

含羟基的3-苯基-4(1H)-喹啉酮衍生物的1H NMR

在抗骨质疏松药物的设计中,根据电子等排原理和药物的构效关系理论,设计并同时合成了7-羟基-3-苯基-4(1H)-喹啉酮新衍生物以及其同分异构体5-羟基-3-苯基-4(1H)-喹啉酮新衍生物.本文报道上述新化合物的¹H NMR数据.     

1-(4-硝基苯氨基乙酰基)-4-苯乙酰基氨基硫脲的NMR谱研究

利用二维核磁共振技术,对所合成的新化合物1-(4-硝基苯氨基乙酰基)-4-苯乙酰基氨基硫脲的¹H NMR 和¹³C NMR谱进行了全归属.     

~1H NMR确证6-氟-5(或7)-氯-3-苯基-4-(1H)-喹啉酮衍生物的结构

作者合成了６氟３（取代）苯基４（１Ｈ）喹啉酮的５氯衍生物与７氯衍生物，二者极性差异小，难于分离，以混合物形式存在．所合成的化合物均未见文献报道，本文通过１ＨＮＭＲ上的化学位移、积分面积以及偶合常数确证了混合物中两组份的结构．     

槲皮素-3-鼠李糖-(6-对羟基反式桂皮酰)葡萄糖甙1-2连接的NMR谱证据

用2D NMR技术研究了从银杏叶提取物中分离的一个黄酮双糖甙[槲皮素-3-鼠李糖-(6-对羟基反式桂皮酰)葡萄糖甙]的结构,对鼠李糖部分的¹H NMR,¹³C NMR化学位移进行了归属.¹³C化学位移和¹H NOE相关性都证明鼠李糖为1″-2″连接.     

苄基硫代半卡巴腙的IR及1HNMR

采用Gaussian09软件,用密度泛函理论的B3LYP方法,在6-31G基组水平上优化了苄基硫代半卡巴腙的分子结构,得到了其稳定构型及其能量.在优化结构的基础上用Hartree-Fock (HF)/6-31G方法计算了该分子的红外光谱振动频率并绘制了红外光谱图,对图中各峰位进行了分析探讨,用同样的方法计算了该分子的核磁共振氢谱.     

Geometry, Electronic Structure, and Related Properties of Dye Sensitizer:3,4-bis[1-(carboxymethyl)-3-indolyl]-1H-pyrrole-2,5-dione

运用密度泛函理论中的杂化泛函B3LYP研究了太阳能电池染料敏化剂3,4-二-[1-(羧甲基)-3-吲哚]-1H-吡咯-2,5-二酮(BIMCOOH)的几何结构、电子结构、极化率和超极化率,并用半经验量子化学方法ZINDO-l和含时密度泛函理论(TDDFT)研究了电子吸收谱．自然键轨道方法的研究结果表明,布居于二酮、吲哚和乙酸基团的自然电荷分别为-0.15e、-0.29e、0.44e．计算的各向同性极化率、极化率各向异性不变量和平均超极化率分别是305.4、188.3、1155.4 a.u.．基于TDDFT的计算结果和实验结果的定性符合指认了在可见和近紫外区的吸收属于∏→∏*跃迁,并且TDDFT的计算结果显示,第9～11个激发态的跃迁与光诱导分子内电荷转移过程有关．对电子结构和紫外-可见吸收谱的分析表明,吲哚基团对光电转换过程的敏化起主要作用,发生于染料敏化剂BIMCOOH和TiO2电极界面之间的电荷转移是由染料分子激发态向半导体导带的电子注入过程．     

Quinazoline-2,4(1H,3H)-diones inhibit the growth of multiple human tumor cell lines

Quinazoline-2,4( $1H,3H$ )-diones exhibit a wealth of biological activities including antitumor proliferation. We established an improved method for the synthesis of quinazoline-2,4( $1H,3H$ )-dione derivatives with three points of molecular diversity. Data indicate that compounds 60 (average $\text{ logGI}_{50} \!=\! -6.1$ ), 65 (average $\text{ logGI}_{50} \!=\! -6.13$ ), 69 (average $\text{ logGI}_{50} \!=\! -6.44$ ), 72 (average $\text{ logGI}_{50} \!=\! -6.39$ ), and 86 (average $\text{ logGI}_{50} = -6.45$ ) significantly inhibited the in vitro growth of 60 human tumor cell lines tested. Structure–activity relationship analyses indicate that chlorophenethylureido is the necessary substituent at the $\text{ D}_{3}$ diversity point (7-position of quinazoline-2,4( $1H,3H$ )-dione), in particular, $o$ -chlorophenethylurea (69) achieved optimal activity. $o$ - or $m$ -Chlorophenethyl substitutions (69 and 72) at the $\text{ D}_{2}$ diversity point (3-position of quinazo line-2,4( $1H,3H$ )-dione) gave the most potent compounds. Methoxyl and 4-methylpiperazin-1-yl substitution at the $\text{ D}_{1}$ diversity point (6-position of quinazoline-2,4( $1H,3H$ )-dione skeleton) may yield better activity than other groups. The quinazoline-2,4( $1H,3H$ )-dione scaffold can be effectively replaced by 2 $H$ -benzo[b][1,4]thiazin-3(4 $H$ )-one.     

N-异丁酰基-3'-O-(1-氟-1,1,3,3-四异丙基-1,3-二硅氧烷-3-基)-2'-苄氧羰基鸟苷的NMR研究

本文采用氢氟酸吡啶鎓在5′-位选择性断裂1,1,3,3-四异丙基二硅氧烷基保护基的方法得到了核苷衍生物N-异丁酰基-3′-O-（1-氟-1,1,3,3-四异丙基-1,3-二硅氧烷-3-基）-2′-苄氧羰基鸟苷（化合物1）,并应用液相色谱串联质谱（LC-MS）、气相色谱-高分辨质谱（GC-HRMS）、液体1D和2D NMR谱（包括¹H NMR、¹³C NMR、¹⁹F NMR、DEPT、¹H-¹H COSY、¹H-¹³C HSQC和¹H-¹³C HMBC）,对产物的¹H、¹³C和¹⁹F NMR信号进行了归属,确定了其结构．     

1H and 13C NMR Spectral Study of Some 2r-Aryl-6c-phenylthian-4-ones,Their 1-Oxides and 1,1-Dioxides

ABSTRACT

Four 2r-aryl-6c-phenylthian-4-ones 1b?1e and their 1-oxides 2b?2e and 1,1-dioxides 3b?3e have been newly synthesized. ¹H and ¹³C NMR spectra have been recorded for all these compounds and 2r,6c-diphenylthian-4-one 1-oxide 2a. ¹³C NMR spectrum has been recorded for the sulfone 3a of 1a. For selected compounds ¹H-¹H COSY, HSQC, HMBC, and NOESY spectra have been recorded. The vicinal proton–proton coupling constants suggest that in all these compounds, the heterocyclic ring adopts chair conformation with equatorial orientations of the aryl and phenyl groups. Proton and carbon chemical shifts suggest that in the sulfoxides, the S=O bond is axial and enhances the J _aa value by some special effect. The S = O bond causes a significant upfield shift even on carbons without hydrogens. Significant solvent shifts also were observed.     

2,4—二氨基—6—(取代苄基)—5—甲基吡啶(2,3d)并嘧啶类化合物的~(13)C NMR研究

2,4-二氨基-6-(取代苄基)-5-甲基吡啶(2,3d)并嘧啶类化合物是一类很有前途的抗癌新药。本文研究了24种7位氯代和氧代的该类化合物的碳谱,归属了母核及取代苄基上各碳的化学位移,并对两种取代对母核碳上的化学位移的影响规律进行了探讨,文中所有数据迄今未见文献报道。     

Novel luminescent hybrid materials by covalently anchoring 2-[3-(triethoxysilyl) propyl-1H-Benz [de]isoquinoline-1, 3(2H)-dione to bimodal mesoporous materials

We report on the synthesis of luminescent hybrid mesoporous materials (LHMS) by covalently anchoring 2-[3-(triethoxysilyl) propyl-1H-Benz [de]isoquinoline-1, 3(2H)-dione to bimodal mesoporous materials (BMMs) through postsynthesis methods. The resulting samples were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), N₂ adsorption/desorption isotherms, transmission electron microscopy (TEM), ²⁹Si NMR analysis, elemental analysis, and fluorescence measurements. The results revealed that luminescent organic molecules have been successfully introduced into the pore channels of BMMs without disrupting the structure, whereas the ordering degree of BMMs framework decreased after functionalization. The obtained materials (LHMS-10) showed excellent luminous performance, and the emission peak shifted to a lower wavelength in comparison with that of pure luminescent dyes (from 464 to 454 nm) because of the polarity of the silica matrix. And the amount of fluorescence molecule had some influence on the luminescence behavior, which was also investigated and discussed. It can be concluded that the fluorescence properties of the dye molecule can be controlled at will by the loading amount.     

1H NMR Spectral Simplification with Achiral and Chiral Lanthanide Shift Reagents. Methastyridone, 2,2-Dimethyl-5-(2-Phenylethenyl)-4-Oxazolidinone

Abstract

The 60 MHz ¹H NMR spectra of methastyridone, 2,2-dimethyl-5-(2-phenylethenyl)-4-oxazolidinone, 1, have been studied at 28° in CDCl₃ solution with the achiral reagent tris(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato)europium(III), 2, Eu(FOD)₃, and the chiral reagent tris[3-(heptafluoropropylhydroxy-methylene)-d?camphorato]europium(III), 3, Eu(HFC)₃.     

Spectral behavior study of 3-(4-dimethylamino-phenyl)-1-{6-[3-(4-dimethylamino-phenyl)-acryloyl]-pyridin-2-yl}-propanone

The photophysical properties such as singlet absorption, molar absorptivity, fluorescence spectra, fluorescence quantum yield (?_f) and transition dipole moment (μ₁₂) of 3-(4-dimethylamino-phenyl)-1-{6-[3-(4-dimethylamino-phenyl)-acryloyl]-pyridin-2-yl}-propanone (DMAPAPP) have been studied in different media. DMAPAPP exhibits a large red-shift in both absorption and emission spectra as the solvent polarity increases, indicating a large change in dipole moment of molecule upon excitation. The fluorescence quantum yield depends on the nature of the solvent. The absorption and emission spectra of DMAPAPP in dioxane–water mixture are also studied. The effect of different type of surfactants to determine their critical micellar concentration (CMC) and the microemulsion effect on the electronic absorption and emission spectra of DMAPAPP are recorded. The effect of acidity on the electronic absorption and emission spectra of DMAPAPP is studied to determine the pK_a and pK_a^? values.     

1H NMR study of proton dynamics in (NH4)3H(SO4)2

Proton dynamics in (NH₄)₃H(SO₄)₂ has been studied by means of ¹H solid-state NMR. The ¹H magic-angle-spinning (MAS) NMR spectra were traced at room temperature (RT) and at Larmor frequency of 400.13 MHz. ¹H static NMR spectra were measured at 200.13 MHz in the range of 135–490 K. ¹H spin-lattice relaxation times, T₁, were measured at 200.13 and 19.65 MHz in the ranges of 135–490 and 153–456 K, respectively. The ¹H chemical shift for the acidic proton (14.7 ppm) indicates strong hydrogen bonds. In phase III, NH₄⁺ reorientation takes place; one type of NH₄⁺ ions reorients with an activation energy (E_a) of 14 kJ mol^− 1 and the inverse of a frequency factor (τ₀) of 0.85 × 10^− 14 s. In phase II, a very fast local and anisotropic motion of the acidic protons takes place. NH₄⁺ ions start to diffuse translationally, and no proton exchange is observed between NH₄⁺ ions and the acidic protons. In phase I, both NH₄⁺ ions and the acidic protons diffuse translationally. The acidic protons diffuse with parameters of E_a = 27 kJ mol^− 1 and τ₀ = 4.2 × 10^− 13 s. The translational diffusion of the acidic protons is responsible for the macroscopic proton conductivity, as the NH₄⁺ translational diffusion is slow and proton exchange between NH₄⁺ ions and the acidic protons is negligible.