A new epipolythiodioxopiperazine with antibacterial and cytotoxic activities from the endophytic fungus Chaetomium sp. M336

A new compound 6-formamide-chetomin (1) together with chetomin (2) was isolated from solid fermentation products of the endophytic fungus Chaetomium sp. M336, which were elucidated by extensive spectroscopic analyses, including 1D and 2D NMR, and HR-ESI-MS experiments. The bioassay result showed that compound 1 had strong antibacterial activity against Escherichia coli, Staphylococcus aureus, Salmonella typhimurium ATCC 6539 and Enterococcus faecalis with minimum inhibitory concentration (MIC) value of 0.78 μg/mL; meanwhile it exhibited strong cytotoxicity with IC₅₀ values of 21.6–27.1 nM against cell lines HeLa, SGC-7901 and A549.     

A new isoflavone from the roots of Ficus auriculata

A new isoflavone, 5,7,4′-trihydroxy-3′-hydroxymethylisoflavone (1), together with three known isoflavones, 3′-formyl-5,4′-dihydroxy-7-methoxyisoflavone (2), ficuisoflavone (3) and alpinumisoflavone (4), were isolated from the roots of Ficus auriculata. Among them, 1 is a rare isoflavone containing 16 carbon atoms on the carbon skeleton. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All compounds were evaluated for their antibacterial activities against five terrestrial pathogenic bacteria in vitro. Compounds 1–4 showed significant antibacterial activities against various terrestrial pathogenic bacteria with MIC values ranging from 1.30 to 39.93 μM.     

Neomacrodione: a new degraded diterpenoid from the roots of Neoboutonia macrocalyx Beng (Euphorbiaceae)

One new degraded diterpenoid 3,6-dihydroxy-1,7-dimethyl-9,10-phenantroquinone (neomacrodione) (1) together seven known compounds were isolated from the roots of Neoboutonia macrocalyx (Euphorbiaceae). The structures of the compounds were established based on their NMR and mass spectrometric data in conjunction with those previously reported in the literature. Compound (1) displayed moderate antibacterial activities.     

Modification of natural fibers from Thespesia lampas plant by in situ generation of silver nanoparticles in single-step hydrothermal method

Ligno-cellulosic fibers have a great market and propose higher value addition and options to develop various products but they do not have inherent antimicrobial properties. In this study, a simple hydrothermal method was applied to build up antimicrobial properties to natural fibers by in situ-generating silver nanoparticles (AgNPs) in them. Herein, the ligno-cellulosic Thespesia lampas natural fibers were selected to develop antimicrobial activity using silver nitrate (AgNO₃) solution by hydrothermal method. The modified fibers were characterized by SEM, FTIR, XRD, TGA, and antibacterial activity tests. The modified fibers had spherical AgNPs with an average size of 95?nm. The thermal stability of the modified fibers was higher than that of the unmodified fibers. The modified fibers exhibited good antibacterial activity against both the Gram negative and Gram positive bacteria. These modified fibers can be considered as fillers in polymer matrices to make antibacterial composites.     

左旋多巴胺Schiff碱的合成,表征和抗菌活性

近来,资料表明Schiff碱作为相转移催化烷基化的良好中间体,在药物合成、催化、分析化学等领域有着重要应用。Schiff碱及其衍生物与金属形成的配合物具有抑菌、杀菌、抗肿瘤、抗病毒等多方面的生物活性,在医学领域有广泛的应用前景[1,2]。本文利用广西丰富的天然资源左旋多巴为原料,与芳香醛酮反应,合成并表征了8种左旋多巴胺Schiff碱(其中4-硝基苯甲醛、香兰醛、4-氯苯甲醛、肉桂醛、大茴香醛及水杨醛缩多巴胺Schiff碱未见文献报道),并研究它们对金黄色葡萄球菌、大肠杆菌的体外抑菌活性。1实验部分1·1药口和试剂硅胶GH254、硅胶H(200-3…     

稀土芦丁配合物的合成、表征及荧光性质和抑菌活性的研究

以稀土金属(Ⅲ)氯化物和芦丁为原料,在乙醇溶液中(pH=7~8)合成了六种稀土芦丁配合物,通过元素分析、IR、UV、热重-差热分析、摩尔电导率的测定对配合物进行了表征,确定了配合物的组成,分析了配合物的热稳定性和热分解行为。同时初步研究了配合物在室温下的荧光性质,结果显示配合物Na5SmLCl7.6H2O(L=C27H29O16)表现出相应的Sm(Ⅲ)离子的特征发射。并研究了配合物的抑菌活性,抑菌活性试验表明六种配合物具有选择性抑菌性能。     

含氟喹诺酮双核铜(Ⅱ)配合物的合成、晶体结构和生物活性

A new binuclear copper(Ⅱ) complex containing fluoroquinolone ligand， [Cu₂(cfc)₂(bpy)₂(pip)]·6H₂O， was synthesized and its crystal structure was solved. The formula of the complex is C₂₅H₂₆ClCuFN₄O₆， and the crystal-lography data are as follows， triclinic， space group P1， a=6.874(2)?， b=10.761(3)?， c=17.976(5)?， α=80.071(6)°， β=85.253(6)°， γ=79.109(6)°， V=1284.5(6)?3， D=1.542g·cm^-3， F(000)=614， and Z=2. R₁=0.0776 and wR₂=0.2235(I >2σ(I)). The copper atom is five-coordinate with square-based pyramidal geometry and involves two nitrogen atoms from bpy， two oxygen atoms from cfc and one nitrogen atom from pip anion. The stacking effect between cfc and bpy ligands from two neighboring molecules was observed. Both ligand and complex were assayed against gram-positive and gram-negative bacteria by doubling dilutions method， the complex shows the same minimal inhibitory concentration (MIC) as the corresponding ligand against S.Aureus and E.Coli bacteria. The inhibitory effect of the ligand and complex on leukemia HL-60 cell line and liver cancer BEL-7402 cell line have been measured by using MTT (Methyl-Thiazol- Tetrozolium) and SRB (Sulphurhodamin B) assay methods. The results indicated that the complex has strong inhibitory effect on HL-60 cell line and on BEL-7402 cell line. CCDC： 191087.     

Neo-lignans in the Seed Crusts of Trewia nudiflora

Four new neo-lignans were isolated from the chloroform portion of 70% ethanol extract of the seed crusts of Trewia nudiflora L., and were determined to be 9′-methoxy-7′-en-3′,8:4′,7-diepoxyneolignan-3,4,9-triol 1, 9′-methoxy-7′-en-3′,7:4′,8-diepoxyneolignan-3,4,9-triol 2, 9′- ethoxy-7′-en-3′,8:4′,7-diepoxyneolignan-3,4,9-triol 3, 9′-butoxy-7′-en-3′,8:4′,7-diepoxy-neolignan -3,4,9-triol 4, respectively, on the basis of spectral data. The antimicrobial bioassays showed that 4 had evident inhibitory activity against Mycobacterium tuberculosis.     

Two New Antibacterial Flavanones from Sophoraflavescens

The dry root of Sophora flavescens, which is a well-known Chinese herbal medicine, has been used for the treatment of diarrhea, gastrointestinal hemorrhage and eczema1. Here we report the structure elucidation of two new flavanones isolated from this plan…     

{LnⅢ2CoⅡ6}异金属配合物的合成及性质

以6-氯-2-羟基吡啶（Hcp）为配体，特戊酸（Hpiv）为辅助配体，设计合成了5例八核{Ln^Ⅲ₂Co^Ⅱ₆}（Ln=Sm（1）、Eu（2）、Tb（3）、Er（4）、Tm（5））异金属配合物。单晶结构表明配合物1~5为同构物，属于三斜晶系，空间群为P1。磁性测试表明，在配合物1~5中，反铁磁相互作用占主导作用。在抑菌性测试中，采用培养基扩散法测试配合物1~5及其同构物{Ln^Ⅲ₂Co^Ⅱ₆}（Ln=Dy（6）、Ho（7）、Gd（8）、Y（9））的抑菌作用。研究表明配合物1~9对大肠杆菌（E.coli）和金黄色葡萄球菌（S.aureus）都有一定的抑制作用。其中，配合物5对E.coli的抑菌效果最好，而配合物9对S.aureus的抑菌效果最好。