钯铂抗癌配合物初步筛选的荧光法研究

用溴化乙锭/DNA体系荧光筛选法,对以二齿胺或氨为第一配体、硝酸根或生物大分子(小牛血清白蛋白或葡聚糖)为第二配体合成的14种钯、铂配合物进行了研究。确定了配合物的抗癌活性及其DNA的结合常数K_M;发现低浓度下硝酸根配体配合物以插入方式与DNA结合,而大分子配体配合物与DNA作用并非单一的插入方式。本法操作简便、受环境影响小,且对抗癌配合物筛选结果与其它体外法基本接近。     

Preliminary Screening of Non-platinum Complexes of Schiff Bases as Antitumour Agents Using Fluorimetry

Based on the consistency of the in vivo and in vitro interactions of drugs with DNA, a fluorimetric method has been developed as a new in vitro method for preliminary screening of antitumour agents. This method was tested using Schiff bases synthesized from salicylaldehyde with 1-alanine, 1-asparagine and 1-histidine, and complexes of these Schiff bases with Cu(Ⅱ), Zn(Ⅱ), Ni(Ⅱ) and Sn(Ⅳ) as potential antitumour agents.The study of the interaction of the complexes with DNA by a fluorescence probe ethidium bromide (EthBr)-DNA system indicated the parallelism between the binding constants and antineoplastic ratios. The relationship between structure and antitumonr activity was investigated.     

The Synthesis and Biological Evaluation of Aloe-Emodin-Coumarin Hybrids as Potential Antitumor Agents

A series of novel aloe-emodin–coumarin hybrids were designed and synthesized. The antitumor activity of these derivatives was evaluated against five human tumor cell lines (A549, SGC-7901, HepG2, MCF-7 and HCT-8). Some of the synthesized compounds exhibited moderate to good activity against one or more cell lines. Particularly, compound 5d exhibited more potent antiproliferative activity than the reference drug etoposide against all tested tumor cell lines, indicating that it had a broad spectrum of antitumor activity and that it may provide a promising lead compound for further development as an antitumor agent by structural modification. Furthermore, the structure–activity relationship study of the synthesized compounds was also performed.     

Synthesis and Biological Evaluation of Laxiflorin J Derivatives as Potential Antitumor Agents

Laxiflorin J, isolated from the leaves of Isodon eriocalyx var. laxiflora, showed significant inhibitory activity toward T‐24 cells. A series of laxiflorin J derivatives were synthesized and their in vitro activity was evaluated against BEL‐7402, A‐549, HT‐29, HL‐60, MOLT‐4 tumor cell lines, with IC₅₀ values ranging from 1.3 to 42.2 μg mL^?1.     

Design,Synthesis of Novel Thiourea and Pyrimidine Derivatives as Potential Antitumor Agents

1,3‐Bis‐(arylidene)thiourea derivatives ( 11a‐c ) were prepared by reacting thiourea ( 9 ) with bezaldehyde, p‐chlorobenzaldehyde or p‐anisaldehyde ( 10a‐c ) respectively. Further reaction of ( 11b ) with acetyl acetone, ethyl acetoacetate, malononitrile and acetic anhydride gave tetrahydropyrimidine‐2‐thiones ( 12‐14 ) and 1,3‐diacetyl thiourea ( 15 ). Compound ( 11b ) reacted with chloroacetyl chloride to give the corresponding pyrimidin‐4‐one derivative ( 16 ). Reaction of ( 12‐14 ) with acetic acid in aqueous sodium nitrite yielded the corresponding oxime derivatives ( 17‐19 ). The triazole ( 20 ) was achieved via refluxing of ( 19 ) in dimethylformamide. Reaction of ( 16 ) with mercaptoacetyl chloride gave the sulfanyl‐acetic acid ( 21 ) which afforded the dihydrazinyl ( 22 ) up on treatment with hydrazine hydrate. Newly synthesized compounds ware characterized by elemental analyses and spectral data (IR, ¹H‐NMR, ¹³C‐NMR and mass spectra). The investigated compounds were screened for their cytotoxicity, i.e. compounds 19 , 20 and 22 exhibited highly potential antitumor activity.     

Synthesis of Pyridotriazolopyrimidines as Antitumor Agents

2‐Hydrazino‐5,7‐di‐p‐tolylpyrido[2,3‐d ]pyrimidin‐4(3H )‐one ( 4 ) was prepared and condensed with different aldehydes 5a , 5b , 5c , 5d , 5e , 5f , 5g to give the corresponding hydrazone derivatives 6a , 6b , 6c , 6d , 6e , 6f , 6g . Oxidative cyclization of the latter compounds 6a , 6b , 6c , 6d , 6e , 6f , 6g gave the corresponding pyrido[2,3‐d ][1,2,4]triazolo[4,3‐a ]pyrimidin‐5(1H )‐ones 7a , 7b , 7c , 7d , 7e , 7f , 7g . Furthermore, compound 4 reacted with benzoyl chloride, triethyl orthoformate, acetyl chloride, ethyl chloroformate, and carbon disulphide in alcoholic KOH solution to afford the corresponding pyrido[2,3‐d ][1,2,4]triazolo[4,3‐a ]pyrimidinones ( 7a , 8 , 9 , 10 , 11 ). The reaction of thione 3 or its 2‐methylthio derivative 16 with hydrazonoyl halides 12a , 12b , 12c , 12d , 12e , 12f , 12g , 12h , 12i , 12j , 12k , 12l , 12m yielded the corresponding pyrido[2,3‐d ][1,2,4]triazolo[4,3‐a ]pyrimidinones 15a , 15b , 15c , 15d , 15e , 15f , 15g , 15h , 15i , 15j , 15k , 15l , 15m . The structures of all the products were confirmed by elemental and spectral analyses (¹H NMR, ¹³C NMR, IR, and MS). In addition, the anticancer activity of 20 pyridotriazolopyrimidinones against two cancer cell lines namely MCF‐7 and HepG2 was evaluated, and the results revealed that compounds 7d and 9 have promising activity , compared with doxorubicin, which used as standard reference drug.     

New Cu+2 Complexes with N-Sulfonamide Ligands: Potential Antitumor,Antibacterial, and Antioxidant Agents

Nowadays, the discovery of a new non-toxic metal complex with biological activity represents a very active area of research. Two Cu⁺² complexes, [Cu(L1)₂(H₂O)₃] (C1) (HL1= N-(5-(4-methylphenyl)-[1,3,4]–thiadiazole–2-yl)-naphtalenesulfonamide) and [Cu(L2)₂(py)₂(H₂O)] (C2) (HL2= N-(5-ethyl-[1,3,4]–thiadiazole–2-yl)-naphtalenesulfonamide), with two new ligands were synthesized. The X-ray crystal structures of the complexes were determined. In both complexes, Cu⁺² is five-coordinated, forming a CuN₂O₃ and CuN₄O chromophore, respectively. The ligands act as monodentate, coordinating the metal ion through a single N_thiadiazole atom; for the C2 complex, the molecules from the reaction medium (pyridine and water) are also involved in the coordination of Cu⁺². The complexes have a distorted square pyramidal square-planar geometry. The compounds were characterized by FT-IR, electronic EPR spectroscopy, and magnetic methods. The nuclease activity studies confirm the complexes’ capacity to cleave the DNA molecule. Using a xanthine-xanthine oxydase system, the SOD mimetic activity of the complexes was demonstrated. Cytotoxicity studies were carried out on two tumor cell lines (HeLa, WM35) and on a normal cell line (HFL1) using the MTT method, with cisplatin used as a positive control. The antibacterial activity of the complexes was investigated against two Gram-positive and two Gram-negative bacteria, and compared with Amoxicillin and Norfloxacin using the disk diffusion method. Both complexes showed in vitro biological activity but the C2 complex was more active. A lack of in vivo toxicity was demonstrated for the C2 complex by performing hepatic, renal, and hematological studies on Swiss mice.     

Copper (II)-Surfactant Complex and Its Nano Analog as Potential Antitumor Agents

The in vitro anticancer activity of copper cetyl trimethyl ammonium bromide (Cu-CTAB)-loaded cyclodextrin nanoparticles on Ehrlich ascites carcinoma (EAC), colon cancer cells (HCT 116), liver cancer cells (HepG-2), breast cancer cells (MCF-7), and cervix cancer cells (Hela) was investigated using MTT due assay. Cyclodextrin nanoparticles loaded with Cu-CTAB exerted in vitro anticancer activity against the previous human cancer cell lines comparable to the activity of free non-entrapped in nanoparticles macro-particle Cu-CTAB. The nano analog was synthesized by physical loading using grinding with ball mill. The ratio between Cu-CTAB and cyclodextrin oligosaccharide was 1 Cu-CTAB: 3 cyclodextrin. The particle size of the nano derivative was determined using the transmitted electron microscope (TEM).     

Design,Synthesis and Pharmacological Evaluation of Novel 4-Phenoxyquinoline Derivatives as Potential Antitumor Agents

A series of novel 4-phenoxyquinoline derivatives containing 3-amino-2-cyano-acrylamide framework was designed and synthesized, and the in vitro cytotoxic activities of them against five cancer cell lines(HT-29, H460, A549, MKN-45, and U87MG) were evaluated. Most of the compounds exhibited moderate-to-significant cytotoxicity and high selectivity against one or more cell lines as compared with Foretinib. The studies of their preliminary structure-activity relationships(SARs) indicate that the compounds containing methyl groups, especially methyl groups at 4-position of the phenyl ring(moiety B) are more effective. Among them, compound 36 shows the most potent antitumor activities with IC₅₀ values of 0.04, 0.09, 0.67, 0.39 and 1.10 μmol/L against HT-29, H460, A549, MKN-45 and U87MG cell lines, respectively.     

Synthesis of Some Novel 2,6- Dimethoxyhydroquinone-3- mercaptoacetyl-peptide Conjugates as Potential Antitumor Agents

2, 6 - D imethoxyhydroquinon e - 3 -mere aptoac et ic ac id (D M Q -MA) I -3 is a syntheti cderivative of 2, 6 - d imethoxyp -b enzoqu inone (D M Q )#, whi oh is a n atUral fermentedproduct of wheat germ and was found to have a wide spectrUm of cytotoxicity againstvarious tUmor cell lines under the synergistic activation of L-ascorbic acid as reported byG.A.Szents. Owing to the very low aqueous solubility of DMQ, which is an apparentdisadvantage for the development as a vaccine, we prep…     

Biflavonoids from Selaginella doederleinii as Potential Antitumor Agents for Intervention of Non-Small Cell Lung Cancer

Four new biflavonoids (1–4) were isolated from Selaginella doederleinii together with a known biflavonoid derivative (5). Their structures contained a rare linker of individual flavones to each other by direct C-3-O-C-4′′′ bonds, and were elucidated by extensive spectroscopic data, including HRESIMS, NMR and ECD data. All isolates significantly inhibited the proliferation of NSCLC cells (IC₅₀ = 2.3–8.4 μM) with low toxicity to non-cancer MRC-5 cells, superior to the clinically used drug DDP. Furthermore, the most active compound 3 suppressed XIAP and survivin expression, promoted upregulation of caspase-3/cleaved-caspase-3, as well as induced cell apoptosis and cycle arrest in A549 cells. Together, our findings suggest that 3 may be worth studying further for intervention of NSCLC.     

CoII Complexes as Liposomal CEST Agents

Three paramagnetic Co^II macrocyclic complexes containing 2‐hydroxypropyl pendant groups, 1,1′,1′′,1′′′‐(1,4,8,11‐tetraazacyclotetradecane‐1,4,8,11‐tetrayl)tetrakis‐ (propan‐2‐ol) ([Co(L1)]²⁺, 1,1′‐(4,11‐dibenzyl‐1,4,8,11‐tetraazacyclotetradecane‐1,8‐diyl)bis(propan‐2‐ol) ([Co(L2)]²⁺), and 1,1′‐(4,11‐dibenzyl‐1,4,8,11‐tetraazacyclotetradecane‐1,8‐diyl)bis(octadecan‐2‐ol) ([Co(L3)]²⁺) were synthesized to prepare transition metal liposomal chemical exchange saturation transfer (lipoCEST) agents. In solution, ([Co(L1)]²⁺) forms two isomers as shown by ¹H NMR spectroscopy. X‐ray crystallographic studies show one isomer with 1,8‐pendants in cis‐configuration and a second isomer with 1,4‐pendants in trans‐configuration. The [Co(L2)]²⁺ complex has 1,8‐pendants in a cis‐configuration. Remarkably, the paramagnetic‐induced shift of water ¹H NMR resonances in the presence of the [Co(L1)]²⁺ complex is as large as that observed for one of the most effective Ln^III water proton shift agents. Incorporation of [Co(L1)]²⁺ into the liposome aqueous core, followed by dialysis against a solution of 300 mOsm L^?1 produces a CEST peak at 3.5 ppm. Incorporation of the amphiphilic [Co(L3)]²⁺ complex into the liposome bilayer produces a more highly shifted CEST peak at ?13 ppm. Taken together, these data demonstrate the feasibility of preparing Co^II lipoCEST agents.     

Study of Palladium Complexes with Chitosan and Its Derivatives as Potential Catalysts for Terminal Olefin Oxidation

FTIR spectroscopy and XPS are used to study palladium complexes with various forms of chitosan: initial and modified by glutaric aldehyde. IR bands are identified that are related to the Pd–N and Pd–O bonds. A difference between the spectra of complexes obtained by the methods of adsorption and coprecipitation of chitosanium hydrochloride with the tetrachloropalladate ion is found. It is shown that the systems studied can be used as catalysts for terminal olefin oxidation by oxygen in the presence of H₂O₂. In the course of the reaction, the complexes undergo redox transformations without breaking the structure of the complex or metal transfer to the reaction mixture. The use of heterogenized Pd(II) complexes as catalysts in terminal olefin oxidation leads to the formation of oxidation and isomerization products, similarly to the case of homogeneous oxidation.     

Synthesis and Biological Activity Screening of Newly Synthesized Trimethoxyphenyl-Based Analogues as Potential Anticancer Agents

A group of novel trimethoxyphenyl (TMP)-based analogues were synthesized by varying the azalactone ring of 2-(3,4-dimethoxyphenyl)-4-(3,4,5-trimethoxybenzylidene)oxazolone 1 and characterized using NMR spectral data as well as elemental microanalyses. All synthesized compounds were screened for their cytotoxic activity utilizing the hepatocellular carcinoma (HepG2) cell line. Compounds 9, 10 and 11 exhibited good cytotoxic potency with IC₅₀ values ranging from 1.38 to 3.21 μM compared to podophyllotoxin (podo) as a reference compound. In addition, compounds 9, 10 and 11 exhibited potent inhibition of β-tubulin polymerization. DNA flow cytometry analysis of compound 9 shows cell cycle disturbance at the G2/M phase and a significant increase in Annexin-V-positive cells compared with the untreated control. Compound 9 was further studied regarding its apoptotic potential in HepG2 cells; it decreased the level of MMP and Bcl-2 as well as boosted the level of p53 and Bax compared with the control HepG2 cells.