Synthesis, characterization and high in vitro antitumour activity of novel triphenyltin carboxylates

The synthesis and spectral characterization of six novel triphenyltin compounds are described. The in vitro antitumour activity of three of these compounds against two human tumour cell lines, MCF-7, a mammary tumour, and WiDr, a colon carcinoma, was determined. All three compounds are more active than cis-platin, etoposide and doxorubicin against both tumour cell lines. They are as active as mitomycin C against WiDr, but less active against MCF-7.     

In vitro antitumour activity of some triorganophosphinegold(i) thionucleobases

A series of phosphinegold(I) thionucleobase analogues, [R(3)PAu(SR(x))] (R = Et, Ph or chexyl; HSR(1) = 2-mercaptobenzoic acid, HSR(2) = 2-thiouracil, HSR(3) = 6-mercaptopurine and HSR(4) = 6-thioguanine) have been examined for their in vitro cytotoxicity in L1210 murine leukemia cells in culture. The range of ID(50) values (continuous 48 h exposure) for the complexes is 0.041 - 0.131 muM. The complexes with SR(3) and SR(3) are generally the most active; however, there is no clear trend associated with the phosphine ligands.     

Synthesis, characterization and antitumour activity of metal complexes of 5-carboxy-2-thiouracil

Metal complexes of 5-carboxy-2-thiouracil with Mn(ll), Co(ll), Ni(ll), Cu(ll), Zn(ll) and Cd(ll) ions were synthesized, characterized, and subjected to a screening system for evaluation of antitumour activity against Sarcoma-180 (S-180) tumour cells. The complexes were characterized by elemental analysis, infrared, electronic spectra, room temperature magnetic measurements and powder X-ray diffraction. The antitumour activity results indicate that some complexes have antitumour activity both in vivo and in vitro against S-180 tumour cells.     

Monoliths of Tio2-SiO2: synthesis,characterization and photocatalytic activity

Journal of Porous Materials - Monoliths of TiO2-SiO2 were synthesized by the Evaporation-Induced Self-Assembly (EISA) method and tested in the photocatalytic degradation of 4-chlorophenol. The way...     

Flower-like ZnO-Ag2O composites: precipitation synthesis and photocatalytic activity

Ag₂O-decorated flower-like ZnO composites were fabricated through a chemical precipitation process. X-ray diffraction analysis confirms the co-existence of cubic Ag₂O and wurtzite ZnO phases. Scanning electron microscopy images reveal Ag₂O nanoparticles located on the rough surface of ZnO flowers. The photocatalytic activities of the composites with various mole ratios were evaluated by the degradation of methyl orange (MO) under ultraviolet irradiation, which confirms that the composite shows superior activity to that of pure ZnO and Ag₂O. The improvement can be ascribed to the deposited Ag₂O forming the p-n junction at the interface of ZnO and Ag₂O, resulting in the transfer of photocarriers and suppressing the electron–hole recombination rate.     

Cost-effective synthesis of polyricinoleate: Investigation of coating characteristics,in vitro degradation,and antibacterial activity

Ricinoleic acid (RA) is a component of various bio-based copolymers. However, high-molecular weight polyricinoleate homopolymers are not widely investigated due to high cost of commercial monomer and catalysts. In this work, we present low-cost approach for the synthesis of high-molecular-weight polyricinoleate by preparing large amount of pure monomer and use of lipozyme TL IM as catalyst. First, polymerization conditions were optimized and comparative studies of medium-molecular-weight polyricinoleate (PRA-M) of M_w = 30 000 gmol⁻¹ and high-molecular-weight polyricinoleate (PRA-H) of M_w = 72 000 gmol⁻¹ were conducted. Polyricinoleates were characterized by common spectroscopic, chromatographic, and thermal methods. Solvent casting of polyricinoleates resulted in thin and continuous coating with perfectly smooth surface under SEM observation. AFM analysis of PRA films showed that surface roughness decreased with increasing molecular weight of polyricinoleate (roughness PRA-M = 68.39 nm and PRA-H = 57.36 nm). Degradation studies under in vitro conditions showed that both PRA-M and PRA-H showed good stability with only ~2% of mass loss after 6 months, possibly due to its hydrophobic nature and relatively high-molecular weight. In contrast to RA, PRA-M and PRA-H do not have significant antibacterial effect on Staphylococcus aureus and Escherichia coli. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48172.     

Synthesis and antitumour activity of medium molecular weight phthalimide polymers of camptothecin

Attachment of anticancer agents to polymers has been demonstrated to improve their therapeutic profiles. A new monomer containing camptothecin, 5‐norbonene‐endo‐2,3‐dicarboxylimidoundecanoyl‐camptothecin (NDUCPT) and its homopolymer and copolymer with acrylic acid (AA) were synthesized and spectroscopically characterized. The NDUCPT content in poly(NDUCPT‐co‐AA) obtained by elemental analysis was 51%. The average molecular weights of the polymers determined by gel permeation chromatography were as follows: M_n = 12 100, M_w = 23 400 g mol^?1, M_w/M_n = 1.93 for poly(NDUCPT), M_n = 15 400, M_w = 28 300 g mol^?1, M_w/M_n = 1.83 for poly(NDUCPT‐co‐AA). The IC₅₀ value of NDUCPT and its polymers against U937 cancer cells was larger than that of CPT. The in vivo antitumour activity of all polymers in Balb/C mice bearing the sarcoma 180 tumour cell line was greater than that of CPT at a dose of 100 mg kg^?1. Copyright © 2003 Society of Chemical Industry     

Enzymic synthesis of 1-alkyl-2-acyl-sn-glycero-3-phosphorylethanolamine through ethanolaminephosphotransferase activity in the neuronal and glial cells of rabbit in vitro

The transfer of radioactivity from cytidine-5′-diphosphate ethanolamine into 1-alkyl-2-acyl-sn-glycerophosphorylethanolamine of neuronal and glial cells from adult rabbit brain cortex has been investigated in vitro. The synthesis of 1-alkyl-2-acyl-sn-glycerophosphorylethanolamine in both cell populations was stimulated 23–25-fold by the addition of 6 mM alkylacylglycerol. The neuronal cell-enriched fraction was found to possess/unit protein a 1.7–1.8-fold ethanolaminephosphotransferase activity (EC 2.7.8.1), as compared to the glial fraction, when saturating concentrations (6 mM) of alkylacylglycerols were added in the incubation system. The neuronal/glial ratio was 2.6–2.8 in the absence of lipid acceptor or with low concentrations of alkylacylglycerol. Under most favorable conditions, 6.4 and 3.3. nmoles 1-alkyl-2-acyl-sn-glycerophosphorylethanol-amine/mg protein/30 min was obtained for neurons and glia, respectively. Various kinetic properties of the 1-alkyl-2-acyl-sn-glycerophosphorylethanolamine synthesizing phosphotransferase activity were found to be similar both in neurons and glia.     

Facile synthesis,in vitro biocompatibility,and antibacterial activity of porous hollow hydroxyapatite microspheres

In this study, porous hollow hydroxyapatite (HAp) microspheres are prepared using chitosan microspheres as novel sacrificial templates and their microstructure, biocompatibility, and drug delivery properties are evaluated. Scanning electron microscope (SEM) observations show that HAp microspheres are spherical in morphology with a diameter of 100–300 μm and have a porous and core–shell structure. X-ray diffractometer patterns show that HAp microspheres consist of apatite phase. MTT assay indicates that HAp microspheres are biocompatible and have no significant cytotoxicity. SEM observations show that HAp microspheres support attachment and proliferation of osteoblast MC3T3-E1 cells. After being soaked in the solution of tetracycline hydrochloride (TH, model drug), HAp microspheres adsorb TH with an adsorption capacity of 47% to derive TH-loaded HAp microspheres. When exposed to two types of representative bacteria: Escherichia coli and Staphylococcus aureus, TH-loaded HAp microspheres maintain the biological activity of TH to inhibit the growth of bacteria.     

Microwave‐assisted synthesis of chitosan biguanidine hydrochloride and its antioxidant activity in vitro

Chitosan biguanidine hydrochloride (CSGH) was synthesized by guanidinylation of chitosan hydrochloride (CSH) under microwave irradiation and characterized by Fourier transform infrared spectroscopy, gel permeation chromatography, and element analysis. The antioxidant activity of CSGH was evaluated by both chemical and cellular methods. The results showed that CSGH was better than CSH but slightly inferior to ascorbic acid (Vc) for scavenging 2,2‐diphenyl‐1‐picryl‐hydrazyl (DPPH) free radicals, and the DPPH? scavenging ability of CSGH was dose‐dependent. However, cell experiments indicated CSGH had a superior repairing effect on oxidatively damaged cells. The intervention of CSGH could excellently recover the cell morphology, decrease the level of malondialdehyde, and enhance the activity of superoxide dismutase and glutathione peroxidase. CSGH could be a potential antioxidant reagent, and its antioxidant activity was reflected not only in scavenging the free radicals but also in regulating the oxidation/antioxidation balance of damaged cells. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43570.     

Toxicity profiles in vivo in mice and antitumour activity in tumour-bearing mice of di- and triorganotin compounds

The in vivo toxicity profiles in mice and the antitumour activity in tumour bearing mice were screened for four di-n-butyltin and five triorganotin carboxylates, di-n-butyltin diterebate (5), bis(phenylacetate) (6), bis(deoxycholate) (7), bis(lithocholate) (8), tri-n-butyltin terebate (9), cinnamate (10), and triphenyltin terebate (11).At their maximum tolerated dosis (MTD), no antitumour effect (T/C ~1) was observed for the compounds 5, 7, 9, 10 and 11. The compounds 6 (T/C = 0.51) and 8 (T/C = 0.42) showed clear antitumour activity after single dose administration and might therefore be of interest for further antitumour activity studies.     

Tin-based antitumour drugs: new developments

An overview of the in vitro test results on several human tumour cell lines of several series of organotin compounds synthesized at the Free University of Brussels VUB. Several compounds exhibit excellent antitumour activities. in vivo screening also gave very promising results.     

Enzymic synthesis of ethanolamine plasmalogens through ethanolaminephosphotransferase activity in neurons and glial cells of rabbit in vitro

The de novo synthesis of ethanolamine plasmalogen in isolated neuronal and glial cells from adult rabbit brain cortex was investigated in vitro, using labeled cytidine-5′-diphosphate ethanolamine as lipid precursor. The neuronal cell enriched fraction was found to possess a twofold ethanolaminephosphotransferase activity (EC 2.7.8.1), as compared to the glial fraction. The neuronal/glial ratio was similar both in the absence and in the presence of saturating alkenylacyl glycerol. Under the most favorable conditions, rates of 31 nmoles and 16 nmoles ethanolamine plasmalogen/mg protein/30 min were obtained for neurons and glia, respectively. Several kinetic properties of the phosphotransferase were found to be similar both in neurons and glia, e.g., K_m of cytidine-5′-diphosphate ethanolamine, pH optimum, need for divalent cations; the K_m value for alkenylacyl glycerol was twofold higher in glia (4 mM) than in neurons (2 mM). The neuronal/glial ratio for the phosphatidylethanolamine synthesizing activity was 2, 4.5, and 6 on using diacyl glycerols prepared from ox heart, ox brain, and soybean, respectively. It is concluded that the cytidine-dependent system for ethanolamine plasmalogen and phosphatidylethanolamine synthesis is concentrated prevalently in the neuronal cells, as compared to glia.     

Zeolite-encapsulated 2-(o-aminophenyl)benzimidazole complexes: synthesis,characterization and catalytic activity

Cobalt(II), copper(II) and zinc(II) complexes of 2-(o-aminophenyl)benzimidazole (AmPhBzlH) encapsulated in the super cages of zeolite-Y and ZSM-5 have been synthesized and characterized by spectroscopic studies (IR, UV/visible, EPR), elemental analyses, thermal studies and X-ray diffraction patterns. The catalytic activity of encapsulated complexes was investigated for the hydroxylation of phenol using 30% H₂O₂ as an oxidant. Under optimized reaction conditions, the hydroxylation of phenol yielded catechol and hydroquinone as the major products. All catalysts show good selectivity for diphenol products. A maximum conversion of phenol was obtained with [Cu(AmPhBzlH)]-Y as the catalyst. The results showed that conversion of phenol varies in the order [Cu(AmPhBzlH)]-Y > [Cu(AmPhBzlH)]-ZSM-5 > [Zn(AmPhBzlH)]-Y > [Co(AmPhBzlH)]-Y > [Zn(AmPhBzlH)]-ZSM-5 > [Co(AmPhBzlH)]-ZSM-5 after 6 h of reaction time. Test for the recyclability of the reaction was also carried out and the results indicate their recyclability.     

三苯基锡的微生物降解特性及降解菌差异表达蛋白

考察了克雷伯氏菌(Klebsiella pneumoniae)对浓度为0.1～10 mg·L^-1的三苯基锡(TPhT)的生物降解,分析了在无机盐培养基和去离子水中K.pneumoniae与TPhT作用过程中,其生理特性和蛋白组的变化,以期从降解菌蛋白质组以及菌体离子代谢的角度揭示有机锡的微生物降解机理。实验结果显示K.pneumoniae能有效地将TPhT降解为二苯基锡、一苯基锡和锡。TPhT在无机盐培养基和去离子水中的降解率分别为46.7%～73.6%和25.1%～87.0%。在此过程中TPhT增加了菌体细胞膜的通透性,从而引发细胞膜的损害,刺激了细胞内离子的释放,造成部分细胞的死亡。TPhT诱导菌体表达了部分与蛋白质水解、代谢过程、蛋白质运输、能量转换、TPhT抗性和降解有关的差异蛋白。     

Pyrimidine-derived disulfides as potential antimicrobial agents: synthesis and evaluation in vitro

Antibiotic resistance is a worldwide problem. The synthesis and evaluation of new antimicrobial compounds, without cytotoxicity against human cells, are highly desired. In this paper, the preparation of a class of pyrimidine-derived disulfides is described. Sulfenic acids were generated from suitable precursors and used as reactive intermediates that condensed with the thiol function of thiocytosine. An introductory study on the antimicrobial activity of this disulfide family is reported. Three family components, that revealed no cytotoxicity against human erythrocytes, exhibited inhibitory activity against Gram-positive Staphylococcus aureus.     

EZH2甲基转移酶抑制剂的设计、合成及甲基化抑制活性

对2-(3-甲基-6-甲氧基喹唑啉-2-氨基)-6-(1-苯基-1H-四唑-5-硫甲基)-4-嘧啶酮（DCE-254）进行了分子对接，设计、合成了14种DCE-254类似物。以4-氯乙酰乙酸乙酯和1-苯基-5-巯基四氮唑，盐酸胍，取代苯甲酰氯、取代异硫氰酸酯等为原料，合成了这些类似物Va~Ⅵh。采用MS，1HNMR和13CNMR对这些类似物的结构进行了表征。H3K27me放射性甲基化抑制测试得到了5种具有较强甲基化抑制作用的DCE-254类似物，活性最好的是N-[4-羟基-6-(1-苯基-1H-四氮唑-5-硫甲基)-2-嘧啶]-N''-2-甲氧基-5-甲基苯基硫脲（Ⅵf），其甲基化抑制率达到77% 结果优于DCE-254。     

Template-assisted hydrothermal synthesis and photocatalytic activity of novel TiO2 hollow nanostructures

TiO₂ hollow nanostructures were successfully synthesized by a controlled hydrothermal precipitation reaction using Resorcinol–Formaldehyde resin spheres as templates in aqueous solution, and then removal of the RF resins spheres by calcination in air at 450 °C for 4 h. The obtained TiO₂ hollow spheres were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N₂ adsorption–desorption analysis, and UV–visible diffuse reflectance spectroscopy. The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic decolorization of rhodamine B aqueous solution at ambient temperature under UV illumination. The results indicated TiO₂ hollow nanostructures exhibit the excellent photocatalytic activity probably due to the unique hollow micro-architectures.     

Di-n-Butyl-, Tri-n-Butyl- and Triphenyltin dl-Terebates: Synthesis, Characterization and In Vitro Antitumour Activity

Di-n-butyltin, tri-n-butyltin and triphenyltin terebates were screened against several human tumour cell lines and found comparably or more active than carboplatin, cis-platin, 5-fluorouracil, methotrexate and doxorubicin, some reference compounds used clinically.     

Soluble iron modulates iron oxide particle-induced inflammatory responses via prostaglandin E2 synthesis: In vitro and in vivo studies

Background  

Ambient particulate matter (PM)-associated metals have been shown to play an important role in cardiopulmonary health outcomes. To study the modulation of PM-induced inflammation by leached off metals, we investigated intracellular solubility of radio-labeled iron oxide (⁵⁹Fe₂O₃) particles of 0.5 and 1.5 μm geometric mean diameter. Fe₂O₃ particles were examined for the induction of the release of interleukin 6 (IL-6) as pro-inflammatory and prostaglandin E₂ (PGE₂) as anti-inflammatory markers in cultured alveolar macrophages (AM) from Wistar Kyoto (WKY) rats. In addition, we exposed male WKY rats to monodispersed Fe₂O₃ particles by intratracheal instillation (1.3 or 4.0 mg/kg body weight) to examine in vivo inflammation.