Prenylated Flavonoids with Potential Antimicrobial Activity: Synthesis,Biological Activity,and In Silico Study

Prenylated flavonoids are an important class of naturally occurring flavonoids with important biological activity, but their low abundance in nature limits their application in medicines. Here, we showed the hemisynthesis and the determination of various biological activities of seven prenylated flavonoids, named 7–13, with an emphasis on antimicrobial ones. Compounds 9, 11, and 12 showed inhibitory activity against human pathogenic fungi. Compounds 11, 12 (flavanones) and 13 (isoflavone) were the most active against clinical isolated Staphylococcus aureus MRSA, showing that structural requirements as prenylation at position C-6 or C-8 and OH at positions C-5, 7, and 4′ are key to the antibacterial activity. The combination of 11 or 12 with commercial antibiotics synergistically enhanced the antibacterial activity of vancomycin, ciprofloxacin, and methicillin in a factor of 10 to 100 times against drug-resistant bacteria. Compound 11 combined with ciprofloxacin was able to decrease the levels of ROS generated by ciprofloxacin. According to docking results of S enantiomer of 11 with ATP-binding cassette transporter showed the most favorable binding energy; however, more studies are needed to support this result.     

Synthesis,Crystal Structure and Theoretical Study of Tetranitrodiazidoacetylhexaazaisowurtzitane (TNDAIW)

A novel polycyclic caged compound, tetranitrodiazidoacetylhexaazaisowurtzitane (TNDAIW), has been synthesized by a six‐step reaction. The molecular structures of two key intermediates and TNDAIW were identified. The crystal structure of the titled compound was established by X‐ray crystallography. Semi‐empirical MO calculations were performed with AM1 and PM3 methods based on the crystal structure. The corresponding data of β‐CL‐20 are also given for comparison.     

苯甲酰脲类昆虫生长调节剂———伏虫隆的合成及单晶结构研究

合成得到苯甲酰脲类昆虫生长调节剂Ｎ－（３,５－二氯－２,４－二氯）－Ｎ′－（２,６－二氟苯甲酰基）脲（ｔｒｉｆｌｕｂｅｎｚｕｒｏｎ,伏虫隆）,并地其单晶结构进行了测定和研究,发现其属于三斜晶,Ｚ＝６,且在一个晶胞中有三个具有不同构橡的伏虫隆分子,而作为其活性元的脲桥以分子内氢键形成了一个稳定的六员环。     

Quaternary Selenides EuLnCuSe3: Synthesis,Structures, Properties and In Silico Studies

In this work, we report on the synthesis, in-depth crystal structure studies as well as optical and magnetic properties of newly synthesized heterometallic quaternary selenides of the Eu⁺²Ln⁺³Cu⁺¹Se₃ composition. Crystal structures of the obtained compounds were refined by the derivative difference minimization (DDM) method from the powder X-ray diffraction data. The structures are found to belong to orthorhombic space groups Pnma (structure type Ba₂MnS₃ for EuLaCuSe₃ and structure type Eu₂CuS₃ for EuLnCuSe₃, where Ln = Sm, Gd, Tb, Dy, Ho and Y) and Cmcm (structure type KZrCuS₃ for EuLnCuSe₃, where Ln = Tm, Yb and Lu). Space groups Pnma and Cmcm were delimited based on the tolerance factor t’, and vibrational spectroscopy additionally confirmed the formation of three structural types. With a decrease in the ionic radius of Ln³⁺ in the reported structures, the distortion of the (LnCuSe₃) layers decreases, and a gradual formation of the more symmetric structure occurs in the sequence Ba₂MnS₃ → Eu₂CuS₃ → KZrCuS₃. According to magnetic studies, compounds EuLnCuSe₃ (Ln = Tb, Dy, Ho and Tm) each exhibit ferrimagnetic properties with transition temperatures ranging from 4.7 to 6.3 K. A negative magnetization effect is observed for compound EuHoCuSe₃ at temperatures below 4.8 K. The magnetic properties of the discussed selenides and isostructural sulfides were compared. The direct optical band gaps for EuLnCuSe₃, subtracted from the corresponding diffuse reflectance spectra, were found to be 1.87–2.09 eV. Deviation between experimental and calculated band gaps is ascribed to lower d states of Eu²⁺ in the crystal field of EuLnCuSe₃, while anomalous narrowing of the band gap of EuYbCuSe₃ is explained by the low-lying charge-transfer state. Ab initio calculations of the crystal structures, elastic properties and phonon spectra of the reported compounds were performed.     

二硝酰胺钾的合成、晶体结构及性能

以N-脒基脲二硝酰胺盐(GUDN)和氢氧化钾为原料合成了二硝酰胺钾(KDN),用元素分析、傅里叶红外光谱对其结构进行了表征。培养了KDN的单晶,并通过X射线单晶衍射仪测定了其晶体结构。采用差示扫描量热分析仪(DSC)研究了KDN的热分解行为,并测试了其感度。结果表明,KDN晶体属于单斜晶系,P2(1)/n空间群,晶胞参数为:a=0.661 0(11)nm,b=0.927 2(15)nm,c=0.719 4(12)nm,β=97.568(3)°,V=0.437 1(12)nm~3;Z=4;Dc=2.236g/cm~3;F(000)=288。KDN的熔点为128℃,撞击感度大于50cm,摩擦感度为0,静电感度为142.53mJ,感度低于RDX,是一种钝感的二硝酰胺类含能材料。     

邻苯二甲酰氨基酸的合成及晶体结构

用邻苯二甲酸酐作氨基保护剂,与6种氨基酸缩合制备了邻苯二甲酰氨基酸。重点考察了邻苯二甲酰甘氨酸的合成条件对产物收率的影响,最佳合成条件为:反应温度140℃,反应时间30 min,n(甘氨酸)∶n(邻苯二甲酸酐)=1∶1.2,收率95.6%。以同样的条件合成的另外5种邻苯二甲酰氨基酸的收率也都达到了81%以上。经解析发现,邻苯二甲酰甘氨酸一水合物的晶体结构属单斜晶系,P21/n空间群,晶胞参数:a=7.638 0(15)nm,b=13.803(3)nm,c=10.009(2)nm,β=106.67(3)°,Z=4,Dc=1.466 g.cm-3,μ=0.120 mm-1,F(000)=464。最终偏离因子R=0.060 6,wR=0.164 7。晶体结构分析表明,分子间氢键连接整个分子形成沿[010]方向的锯齿状长链,再通过π-π堆积作用形成稳定的三维立体结构。     

Design,Synthesis, Drug-Likeness and In Silico Prediction of Polycyclic Aromatic Schiff base Tethered Organosilatranes

Silicon - The present article includes the generation of aromatic Schiff base tethered organosilatranes via two step synthetic pathways starting from anthracene-10-carbaldehyde and...     

二苯二硒的合成和晶体结构

报道了一种新的合成工艺,采用氯化镉为催化剂,利用空气中的氧气直接氧化苯硒酚合成了二苯二硒晶体,表征了其晶体结构和红外光谱性质。晶体属于正交晶系,空间群 P21 21 21,a= 0 5646 (2) nm,b= 0 8288 (3) nm,c=2 4100(9)nm; V=1 1276(7)nm3,Dc=1 839 g·cm-3,Z=4, R=0 0259。     

镉苯并咪唑二乙酸配合物的合成、晶体结构和热性能研究

1,3-苯并咪唑二乙酸与镉离子的反应,采用溶液法得到结构新颖的配合物:{[Cd3(η2-L-μ2-η2)2(4,4'-bipy)2(SO4)2(H2O)4]·5H2O}n。通过元素分析、红外光谱、热稳定性对配合物进行了初步表征,且通过单晶X-ray衍射对其晶体结构进行了测定。     

二茂铁吡咯烷衍生物的合成及其晶体结构

以1,1-二氰基-2-二茂铁乙烯、L-脯氨酸和芳香醛为原料,在甲苯中反应合成了含有氰基的二茂铁吡咯烷衍生物。2-对硝基苯基-3-二茂铁基-4,4-二氰基双稠吡咯啶经X-射线衍射方法测定了化合物的晶体结构。晶体属单斜晶系,空间群为C2/c,晶体学参数a=24.395(3)A,b=8.992 3(18)A,c=19.005 4(18)A,V=4 325.7(7)A3,Dx=1.432 g/cm3,Z=8,T=113(2)K,F(000)=1 936,R1=0.040 2,wR2=0.093 8。     

新型对二苯醌衍生物的合成与晶体结构

主要报道了三苯基硼引发的2-烷基取代苯酚双锂盐的自由基偶联反应,生成了硼取代的对二苯醌化合物。有机硼化合物被认为参加自由基反应,以有机硼化合物作为自由基引发剂,并应用于芳烃化合物。我们发现当三苯基硼与2-烷基取代苯酚的双锂盐反应时,促进2-烷基取代苯酚的自由基偶联,生成了一种新型的对二苯醌衍生物,是一种收率较高的对二苯醌衍生物新型制备方法。产物的结构经元素分析、红外光谱和X-射线单晶衍射确定。     

1-甲基-3,4-二硝基吡唑的合成、性能及晶体结构

以3,4-二硝基吡唑(DNP)为原料,通过甲基化制备了1-甲基-3,4-二硝基吡唑(MDNP),采用熔点测定、红外光谱、核磁共振等对目标产物结构进行了表征。室温下培养了MDNP的单晶,用X-射线四圆衍射仪测定了其单晶结构,用DSC法研究了MDNP的热性能,用Kamlet公式计算了MDNP的爆速和爆压。结果表明,该晶体属单斜晶系,空间群P 2 1/n,晶胞参数为a=0.726 3nm,b=1.514 3nm,c=1.036 8nm,V=1.123 4nm3,Z=4,D=1.480g/cm3,F(000)=520。MDNP有良好的热稳定性,爆速和爆压分别为6.14km/s、17.0GPa,是具有潜在应用价值的含能材料。     

4,4′-二碘二苯基砜的合成、谱学表征及其晶体结构

以氯磺酸和碘代苯为原料,经氯磺化反应合成了4,4′-二碘二苯基砜。最佳反应条件为:于-20～-15℃将碘代苯滴入氯磺酸的氯仿溶液,n(碘代苯):n(氯磺酸)=1:3,50℃反应2h,冷却反应液后用碎冰洗涤、无水MgSO4干燥,脱除溶剂,粗产物经苯重结晶,收率82.6%,熔点207～208℃。并通过熔点、元素分析、UV、IR、1HNMR及X射线单晶衍射对产物进行了谱学表征和晶体结构分析。该晶体属于单斜晶系,C2/c空间群,晶胞参数:a=21.612(4)nm,b=4.9550(10)nm,c=14.449(3)nm,α=90.00°,β=117.27(3)°,γ=90.00°,V=1.3754(5)nm3,Dx=2.270g/cm3,Z=4,F(000)=872,μ=4.712mm-1,S=1.078,R=0.0370,wR=0.0897。     

邻羧基苯甲醛缩水合肼席夫碱的合成、晶体结构及表征

采用邻羧基苯甲醛和水合肼两种物质,通过混合溶液法在70℃恒温水浴,合成了一种新型席夫碱晶体。其晶体数据为:三斜晶系,空间群为P1,a=7.228 3(5),b=8.030 7(5),c=11.160 2(9),α=80.064(6)°,β=86.076(6)°,γ=88.624(6)°,Z=12,μ=0.150 mm-1,F(000)=304.0,De=1.587 g/cm3。     

糠醛缩异烟肼席夫碱的合成及其晶体结构

席夫碱配体及其配合物可应用于生物化学、分析化学、材料化学等方面,由于其广泛的应用,已成为现阶段研究者研究的热点。糠醛是重要的化工原料,异烟肼是抗结核病的主要药剂,采用这两种化合物,通过混合溶液法在80℃恒温水浴中,以新制备的糠醛溶液和异烟肼溶液为原料合成了一个小分子席夫碱,通过红外光谱、紫外光谱、质谱、X-射线衍射仪表征其结构。结果表明,该席夫碱属于单斜晶系,空间群为P21/c,晶胞参数为a=10.717 0(6),b=5.238 9(2),c=18.123 5(9),α=90°,β=94.445(5)°,γ=90°,Z=4,μ=0.101 mm-1,F(000)=448,De=1.409 g/cm3。     

Design,Synthesis, In Silico and In Vitro Studies for New Nitric Oxide-Releasing Indomethacin Derivatives with 1,3,4-Oxadiazole-2-thiol Scaffold

Starting from indomethacin (IND), one of the most prescribed non-steroidal anti-inflammatory drugs (NSAIDs), new nitric oxide-releasing indomethacin derivatives with 1,3,4-oxadiazole-2-thiol scaffold (NO-IND-OXDs, 8a–p) have been developed as a safer and more efficient multitarget therapeutic strategy. The successful synthesis of designed compounds (intermediaries and finals) was proved by complete spectroscopic analyses. In order to study the in silico interaction of NO-IND-OXDs with cyclooxygenase isoenzymes, a molecular docking study, using AutoDock 4.2.6 software, was performed. Moreover, their biological characterization, based on in vitro assays, in terms of thermal denaturation of serum proteins, antioxidant effects and the NO releasing capacity, was also performed. Based on docking results, 8k, 8l and 8m proved to be the best interaction for the COX-2 (cyclooxygense-2) target site, with an improved docking score compared with celecoxib. Referring to the thermal denaturation of serum proteins and antioxidant effects, all the tested compounds were more active than IND and aspirin, used as references. In addition, the compounds 8c, 8h, 8i, 8m, 8n and 8o showed increased capacity to release NO, which means they are safer in terms of gastrointestinal side effects.     

New Pyrrole Derivatives as Promising Biological Agents: Design,Synthesis, Characterization,In Silico,and Cytotoxicity Evaluation

The current study describes the synthesis, physicochemical characterization and cytotoxicity evaluation of a new series of pyrrole derivatives in order to identify new bioactive molecules. The new pyrroles were obtained by reaction of benzimidazolium bromide derivatives with asymmetrical acetylenes in 1,2-epoxybutane under reflux through the Huisgen [3 + 2] cycloaddition of several ylide intermediates to the corresponding dipolarophiles. The intermediates salts were obtained from corresponding benzimidazole with bromoacetonitrile. The structures of the newly synthesized compounds were confirmed by elemental analysis, spectral techniques (i.e., IR, ¹H-NMR and ¹³C-NMR) and single-crystal X-ray analysis. The cytotoxicity of the synthesized compounds was evaluated on plant cells (i.e., Triticum aestivum L.) and animal cells using aquatic crustaceans (i.e., Artemia franciscana Kellogg and Daphnia magna Straus). The potential antitumor activity of several of the pyrrole derivatives was studied by performing in vitro cytotoxicity assays on human adenocarcinoma-derived cell lines (i.e., LoVo (colon), MCF-7 (breast), and SK-OV-3 (ovary)) and normal human umbilical vein endothelial cells (HUVECs). The obtained results of the cytotoxicity assessment indicated that the tested compounds had nontoxic activity on Triticum aestivum L., while on Artemia franciscana Kellogg nauplii, only compounds 2c and 4c had moderate toxicity. On Daphnia magna, 4b and 4c showed high toxicity; 2a, 2b, and 2c moderate to high toxicity; only 4a and 4d were nontoxic. The compound-mediated cytotoxicity assays showed that several pyrrole compounds demonstrated dose- and time-dependent cytotoxic activity against all tested tumor cell lines, the highest antitumor properties being achieved by 4a and its homologue 4d, especially against LoVo colon cells.     

7-氨基-6-硝基苯并二氧化呋咱的合成、晶体结构及热分析

以间二氯苯胺为起始原料,用氯乙酰基保护氨基的方法,经乙酰化、硝化、叠氮化及脱氮、水解4步合成了7-氨基-6-硝基苯并二氧化呋咱(ANBDF),其中叠氮化及脱氮反应不经分离一锅完成,脱氮反应在80℃完成,其余反应均在0℃至室温下完成。4步反应的得率分别为97.7%,70.0%,82.5%和80.0%。以IR1、HNMR、MS及元素分析对目标化合物的结构进行了表征。制备并测定了ANBDF的晶体结构,其晶体结构属正交晶系,空间群P2121/n;晶胞参数:a=1.3626(3)nm,b=0.6961(13)nm,c=0.95745(3);Dc=1.931 g.cm-3。晶体结构分析表明,ANBDF是一平面分子,分子内存在氢键,分子结构紧密,密度大。DSC分析结果证明,ANBDF在199.3℃达到最大放热峰,是热稳定性能极佳、极具前途的高能量高密度化合物。     

Flexible and Asymmetric Ligand in Constructing Coordinated Complexes: Synthesis,Crystal Structures and Fluorescent Characterization

Flexible and asymmetric ligand L [L = 1-((pyridin-3-yl)methyl)-1H-benzotriazole], is used as a basic backbone to construct complicated metal-organic frameworks. Two new polymers, namely, [Ag₂(L)₂(NO₃)₂]_n (1) and [Ag(L)(ClO₄)]_n (2), were synthesized and characterized by X-ray structure analysis and fluorescent spectroscopy. The complex 1 gives an “S” type double helical conformation, whereas complex 2 exhibits a 1D zigzag configuration. Different anions affect the silver coordination geometry and crystal packing topology.     

含苯并噻唑环的硫脲类化合物的合成、晶体结构及抑菌活性研究

以取代苯甲酸为原料合成了一系列含苯并噻唑环的硫脲类化合物,其中有8个为新型化合物,化合物结构均经元素分析、IR、1HNMR表征.采用X-射线单晶衍射测定了N-(2-溴苯甲酰基)-N'-(4-甲基苯并噻唑-2-基)硫脲的晶体结构,该晶体属于三斜晶系,P1空间群,晶胞参数a=0.741 68(7) nm,b=1.088 71(10) nm,c=1.206 82(11) nm,α=103.504(8)°,β=106.632(8)°,γ=108.278(8)°,V=0.828 74(13)nm3,Dc=1.628 Mg/m3,μ=2.738 mm-1,Z =2,F(000)=408,最终偏差因子R1=0.030 4,wR2 =0.075 6[I＞2σ(I)],S=1.048,CCDC号为1471387.选择广西主要经济作物(水稻、甘蔗、番茄、木薯、龙眼、荔枝)中常见的病原菌,对目标化合物进行室内抑菌活性测试,结果发现该类化合物具有一定的抑菌活性.