Novel pyrimidinone derivatives: synthesis, antitumor and antimicrobial evaluation

Starting from 6-aryl-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile (4a-d), a series of mono- and dialkyl derivatives 5a-j and 6a, b was synthesized. Hydrazinolysis of 4a, b, d and 5d afforded the hydrazino derivatives 7a-c which were cyclised to give the triazolopyrimidinones 8a-c and the pyrimidotriazinones 9a-c through the reaction with formic acid and chloroacetyl chloride, respectively. Most of the newly synthesized compounds were evaluated for their in-vitro antitumor activity. Compounds 6a and b displayed promising anticancer activity against leukaemia, non-small cell lung, melanoma, and renal cancer. On the other hand, all compounds prepared were screened for their in-vitro antibacterial and antifungal activities. Compounds 5h and j showed significant activity against Staphylococcus aureus, while compounds 5e, 7c and 8c displayed moderate inhibitory activity against Candida albicans.     

Synthesis of certain 2-substituted-1H-benzimidazole derivatives as antimicrobial and cytotoxic agents

A series of 2-substituted-1H-benzimidazole derivatives were synthesized and evaluated for antimicrobial, antifungal and cytotoxic activities. The results showed that all tested compounds showed potent antimicrobial activity against some species of Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Salmonella typhi) and fungi (Candida albicans) with minimum inhibitory concentrations (MICs) lower than 0.016 μg/mL. In contrast, all tested compounds were inactive against Staphylococcus aureus (Gram-positive bacterium). The final targets were also tested for their antitumor activity in vitro on cervical carcinoma (HeLa) cell line. Eight of the test compounds displayed more potent cytotoxic effect than doxorubicin at nanomolar concentrations. Compounds 2c and 3c exerted the strongest cytoyoxic effect with IC(50) 15 and 13 nM, respectively.     

Microwave-Assisted Synthesis,Biological Activity Evaluation,Molecular Docking,and ADMET Studies of Some Novel Pyrrolo [2,3-b] Pyrrole Derivatives

Novel pyrrolo [2,3-b] pyrrole derivatives were synthesized and their hypolipidemic activity was assessed in hyperlipidemic rats. The chemical structures of the new derivatives were confirmed through spectral analysis. Compounds 5 and 6 were revealed to be the most effective hypolipidemic agents, with considerable hypocholesterolemic and hypotriglyceridemic effects. They appear to be promising candidates for creating new powerful derivatives with anti-atherosclerotic and hypolipidemic properties. As for antimicrobial activity, some of the tested compounds showed moderate activity against Pseudomonas aeruginosa: compound 2 revealed an MIC value of 50 μg/mL, compared to 25 μg/mL for ciprofloxacin. Compound 3 showed good antimicrobial activity against Staphylococcus aureus, comparable to ciprofloxacin, and roughly half the activity of ampicillin, according to MIC values. Compound 2 has an MIC approximately 25% of that of clotrimazole against Candida albicans. Compound 2 also showed the highest antioxidant activity with 59% inhibition of radical scavenging activity. Additionally, the cytotoxic activity of these new derivatives 1–7 was investigated and most of them showed good anticancer activity against the three tested cell lines.     

Synthesis and Cytotoxicity Evaluation of Novel Andrographolide‐1,2,3‐Triazole Derivatives

A series of new andrographolide‐1,2,3‐triazole derivatives, 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , were synthesized from a natural bioactive labdane type diterpenoid, andrographolide. All the derivatives were screened against human cancer cell lines MCF7, MDA‐MB‐231, COLO205, HepG2, K562, Hela, and HEK293 to evaluate their cytotoxic activity. All the compounds showed anticancer activity selectively against K562 cell line, with IC₅₀ values ranging from 8.00 to 17.11 µM, and are inactive against the rest of the cell lines. Compounds 3c and 3d showed significant cytotoxicity among the synthesized derivatives. The in silico docking studies revealed compounds 3b and 3d with high binding affinity against the cancer target, transient receptor potential vanilloid 1.     

Synthesis and antimicrobial activities of new 4,6‐diaryl‐ 4,5‐dihydro‐3‐hydroxy‐2H‐indazoles

A series of new 4,6‐diaryl‐4,5‐dihydro‐3‐hydroxy‐2H‐indazoles 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j , 5k were synthesized by the cyclization of ethyl 2‐oxo‐4,6‐diarylcyclohex‐3‐ene carboxylates 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i , 4j , 4k . The compounds were characterized by IR, ¹H NMR, ¹³C NMR, 2D NMR, and elemental analysis. The synthesized compounds were evaluated for in vitro antibacterial and antifungal activities against Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa, Candida albicans, Aspergillus niger, Aspergillus flavus, and Rhizopus sp. Most of the compounds exhibited good activity against the tested organisms. J. Heterocyclic Chem.,, (2012).     

2-苯基-4-硒唑甲酸过渡金属配合物的合成、结构及生物活性研究

合成了2-苯基-4-硒唑甲酸配体(HL)和相应的6个过渡金属配合物[ML2(H2O)2](M=Co,Ni,Cu,Cd)1～4,[ZnL2](5),[CuL2(py)2](6).用元素分析、红外光谱、热重分析等表征手段确定了配合物的组成;用单晶X射线衍射测定了配合物3和6的结构;用溴化乙锭荧光探针初步研究了它们与DNA作用的强度和模式;考察了配体和配合物对大肠埃氏杆菌(E.coliJM109)、大肠杆菌(E.coli,DH5α)、表皮葡萄球菌(S.epidermidis)、金黄色葡萄球菌(S.aureus)、鲍曼不动杆菌(baumanii)、草绿色链球菌(S.viridans)6种细菌的抗菌活性及对正常细胞293T和肿瘤细胞RAW264.72的体外增殖抑制作用.     

Design,Synthesis, Biological Evaluation and Silico Prediction of Novel Sinomenine Derivatives

Sinomenine is a morphinan alkaloid with a variety of biological activities. Its derivatives have shown significant cytotoxic activity against different cancer cell lines in many studies. In this study, two series of sinomenine derivatives were designed and synthesized by modifying the active positions C₁ and C₄ on the A ring of sinomenine. Twenty-three compounds were synthesized and characterized by spectroscopy (IR, ¹H-NMR, ¹³C-NMR, and HRMS). They were further evaluated for their cytotoxic activity against five cancer cell lines, MCF-7, Hela, HepG2, SW480 and A549, and a normal cell line, Hek293, using MTT and CCK8 methods. The chlorine-containing compounds exhibited significant cytotoxic activity compared to the nucleus structure of sinomenine. Furthermore, we searched for cancer-related core targets and verified their interaction with derivatives through molecular docking. The chlorine-containing compounds 5g, 5i, 5j, 6a, 6d, 6e, and 6g exhibited the best against four core targets AKT1, EGFR, HARS and KARS. The molecular docking results were consistent with the cytotoxic results. Overall, results indicate that chlorine-containing derivatives might be a promising lead for the development of new anticancer agents.     

Cytotoxicity of new 5-phenyl-4,5-dihydro-1,3,4-thiadiazole analogues

A series of 5-phenyl-4,5-dihydro-1,3,4-thiadiazoles were synthesized and their cytotoxicity was examined against four human cancer cell lines, e.g. lung cancer (A549), ovarian cancer (SK-OV-3), skin cancer (SK-MEL-2), and colon cancer (HCT15). The title compounds were synthesized by condensation of thiosemicarbazide with substituted benzaldehydes, followed by cyclization with acetic anhydrides in good yields. Most of the compounds exhibited significant suppressive activity against the growth of all of the cancer cell lines. The 4-hydroxy analogue of 5-phenyl-4,5-dihydro-1,3,4-thiadiazole (2h) was most active in the inhibition of growth of the SK-MEL-2 cell line, with an IC(50) value of 4.27 μg/ml; followed by compound 2a (IC(50) 5.16 μg/ml). The compounds 2j, 2h, and 2b, bearing 3-methoxy-4-hydroxy-, 4-hydroxy- and 4-methyl substituents in the C-5 phenyl ring respectively, exhibited the highest activity against the SK-OV-3 (IC(50) 7.35 μg/ml), HCT15 (IC(50) 8.25 μg/ml) and A549 (IC(50) 9.40 μg/ml) cell lines, respectively. A structure-activity relationship study revealed that an optimal electron density on the C-5 phenyl ring of 1,3,4-thiadiazoles is crucial for their cytotoxic activity against the human cancer cell lines used in the present study.     

Synthesis and biological activities of novel 2-amino-1,3-thiazole-4-carboxylic acid derivatives

A series of novel 2-amino-1, 3-thiazole-4-carboxylic acid derivatives were designed and synthesized. Their structures were confirmed by melting points, IR, ¹H NMR, ¹³C NMR, and HRMS or elemental analysis. Biological activities of all title compounds including fungicidal activity and antivirus activity were evaluated systematically. Preliminary bioassays indicated that these compounds exhibited good fungicidal activity at 50 μg/mL, compounds 4b and 4i exhibited over 50% activity against six fungi tested. Most compounds showed good activity against TMV with different models in vivo at 100 μg/mL. Compounds 4c and 4e stood out with high effects against TMV in vivo in all models tested, including protective, inactivative, curative, and inductive activities. These data demonstrate a new strategy for fungi and virus control.     

Design,Synthesis, and Anticancer Activity of 3H–benzo[f]chromen‐3‐one Derivatives

A series of substituted aminomethylbenzocoumarin derivatives 8a–i have been synthesized, characterized, and structure of compound 8g was confirmed by X‐ray single crystal analysis. All the synthesized compounds were tested for their anticancer activity against cancer cell lines A549 (lung carcinoma cell line), MCF7 (breast cancer cell line), and A375 (melanoma cell line). Compounds 8a , 8f , and 8h showed excellent growth inhibitory activity against all three cell lines, respectively. Compounds 8a and 8f were also found to be quite promising at very low concentration as an anticancer agent against MCF7 and A549 cell lines. Compounds 8g and 8i showed excellent antimitotic activity with IC₅₀ 0.32 and19.98 nM for A549 cell line.     

Synthesis, biological and computational study of new Schiff base hydrazones bearing 3-(4-pyridine)-5-mercapto-1,2,4-triazole moiety

A series of new Schiff base hydrazones (compounds 1-16) were synthesized by condensation reaction of 4-amino-3-(4-pyridine)-5-mercapto-1,2,4-triazole with various aldehydes and/or dialdehydes. The structure of the prepared compounds was confirmed by means of 1H NMR, 13C NMR, UV-vis, IR and elemental analyses. The all prepared compounds were assayed for antibacterial (Escherichia coli and Staphylococcus aureus) and antifungal (Candida albicans) activities by disc diffusion method. The results indicate that all tested compounds did not show any antibacterial activity against E. coli, as gram negative bacteria, and antifungal activity against C. albicans. But the compounds 2, 3, 4, 6 and 8 containing 4-Cl, 4-Me, 4-MeO, 2,4-di-Cl and 2-OH substituted phenyl moiety, respectively, showed good inhibition against S. aureus as compare to standard drugs. The structure of all biologically active compounds has also been theoretically studied by ab initio Hartree-Fock (HF) methods.     

Design,Synthesis and Biological Evaluation of Sulfenimine Cephalosporin Analogues as β-Lactamase Inhibitors

A series of sulfenimine cephalosporin derivatives(6a-6t) was designed, synthesized and evaluated for their inhibitory activity against class A β-lactamase(TEM-1) derived from E. coli, and class C β-lactamase (cephalosporinase) derived from wild Bacillus subtilis in cell-free systems. Most of the tested compounds showed enhanced inhibitory activity against class C β-lactamase(cephalosporinase) compared with tazobactam. The most promising compounds 6c and 6o in combination with cefradine(IC₅₀=1.80 and 1.59 μmol/L, respectively) were further investigated against a series of clinical isolated β-lactamase-producing bacterial strains. The results reveal that compounds 6c and 6o in combination with cefradine show two to four times more activity than cefradine alone against methicillin-sensitive Staphylococcus aureus(MSSA) and Klebsiella pneumoniae. The data suggest that the sulfenimine moiety may be beneficial to the activity and selectivity of inhibitors.     

Synthesis and in vitro antimicrobial activity of N-arylquinoline derivatives bearing 2-morpholinoquinoline moiety

A new series of N-arylquinoline derivatives 5a-x bearing 2-morpholinoquinoline moiety has been synthesized by one pot base catalyzed cyclocondensation reaction of 2-morpholinoquinoline-3-carbaldehydes 2a-c,malononitrile 3 andβ-enaminones 4a-h. All the synthesized compounds were screened for their in vitro antimicrobial activity against six bacterial pathogens,namely Streptococcus pneumoniae,Clostridium tetani,Bacillus subtilis,Salmonella typhi,Vibrio cholerae,Escherichia coli and against two fungal pathogens,Aspergillus fumigatus and Candida albicans using broth microdilution MIC method.Of the compounds studied,majority of the compounds were found to active against C.tetani,B.subtilis and C.albicans as compared to first-line standard drugs.     

Synthesis and in vitro antimicrobial screening of new pyrano[4,3-b]pyrane derivatives of 1H-pyrazole

A new series of pyrano[4,3-b]pyrane 4a-l bearing 1H-pyrazole has been synthesized by one pot base catalyzed cyclocondensation reaction of 1H-pyrazole-4-carbaldehyde la-1,malononitrile 2 and 4-hydroxy-6-methylpyrone 3.All the synthesized compounds were screened against six bacterial pathogens,namely B.subtilis,C.tetani,S.pneumoniae,S.typhi,V.cholerae, E.coli and antifungal activity against,two fungal pathogens,A.fumigatus and C.albicans using broth microdilution MIC method. Some of the compounds are found to be equipotent or more potent than that of commercial drugs,against most of employed strains.     

Synthesis,Characterization and Antibacterial Activity of New 5-Aryl Pyrazole Oxime Ester Derivatives

Eleven new 1-{5-[4-（benzyloxy）phenyl]-3-methyl-4,5-dihydropyrazol-l-yl} oxime ester dcrivatives were synthesized and characterized by elemental analysis, HRMS, ^1H NMR data. All the compounds were screened for their antibacterial potential in vitro against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The results indicate that compounds 8c and 8f possess potent activity with the minimum inhibitory concentrations（MIC） of 1.562--3.125 ug/mL against all the four bacteria. Compounds 8c, 8e and 8f show moderate inhibition against the DNA gyrase（IC50=1.9--2.5 ug/mL）. On the basis of the biological activities, structure-activity relationship was discussed.     

Synthesis and Antimicrobial Evaluations of Some Novel Mono‐, Bis‐, and Tris‐Nitro‐1,2,4‐Triazines

Substituted‐1,2,4‐triazines were conveniently synthesized in one pot by the cyclization of arylnitroformaldehyde hydrazone derivatives 1 and 5 with different primary amines in ~37% formaldehyde solution. The synthesized compounds were arranged into novel mono‐, bis‐, and tris‐nitro‐1,2,4‐triazine derivatives 2 , 3 , 4 , 6 , and 7 . The antibacterial and antifungal activity of the synthesized compounds were screened against bacterial strains Escherichia coli (as Gram − ve) and Staphylococcus aureus (as Gram + ve), and fungal strains Aspergillus flavus and Candida albicans . All the synthesized compounds exhibit various patterns of inhibitory activity on the two pathogenic bacterial strains. However, the same compounds showed no activity against the tested fungal strains.     

5-芳甲氧基-3(2H)-哒嗪酮衍生物的设计、合成与生物活性

为寻找新型昆虫生长调节活性化合物, 设计合成了15个未见文献报道的5-芳甲氧基取代的3(2H)-哒嗪酮衍生物, 所有化合物结构均通过¹H NMR, IR和元素分析确证. 初步生物活性研究表明, 化合物8o对2龄家蝇幼虫有明显的抑制作用; 化合物8a, 8c, 8g和8j对3龄蝗蝻显示出较好的生物活性. 对目标化合物的构效关系亦进行了初步探讨.     

Synthesis, characterization, and antimicrobial evaluation of oxadiazole congeners

A series of 1,3-oxazole, 1,3-thiazole, isomeric 1,2,4-oxadiazole, 1,3,4-oxadiazole, and 1,2,3,4-tetrazole heterocycles was synthesized. All the compounds shared as a common feature the presence of a 4-hydroxyphenyl substituent. The structures of the synthesized compounds were confirmed by MS, 1H-NMR, and elemental analysis. In vitro antimicrobial activity for all the newly synthesized compounds at concentrations of 200-25 μg/mL was evaluated against Gram+ve organisms such as methicillin-resistant Staphylococcus aureus (MRSA), Gram-ve organisms such as Escherichia coli (E. coli), and the fungal strain Aspergillus niger (A. niger) by the cup plate method. Ofloxacin and ketoconazole (10 μg/mL) were used as reference standards for antibacterial and antifungal activity, respectively. Compounds 15, 16, and 20 showed notable antibacterial and antifungal activities at higher concentrations (200 μg/mL), whereas 17-19 were found to display significant antibacterial or antifungal activity (25-50 μg/mL) against the Gram+ve, Gram-ve bacteria, or fungal cells used in the present study.     

Synthesis and biological evaluation of dihydrotriazine derivatives as potential antibacterial agents

A series of 1,4-dihydro-1,3,5-triazine derivatives were designed and synthesized and their antibacterial and antifungal activities were evaluated. Most of the synthesized compounds showed potent inhibition of several Gram-positive bacterial strains(including multidrug-resistant clinical isolates) and Gramnegative bacterial strains, with minimum inhibitory concentrations(MICs) in the range of 2.1–181.2 mmol/L. Compounds 7a and 7c presented the most potent inhibitory activities against Grampositive bacteria(e.g., Staphylococcus aureus 4220), Gram-negative bacteria(e.g., Escherichia coli 1924),and the fungus Candida albicans 7535, with MICs of 2.1 or 4.1 mmol/L. Especially, compound 7a was the most potent, with an MIC of 2.1 mmol/L against four multidrug-resistant, Gram-positive bacterial strains.The cytotoxic activity of the compound 7a, 7c and 7f was assessed in HepG2 cells, and the results suggest that 1,4-dihydro-1,3,5-triazine derivatives bearing a 6-benzyloxynaphthalen moiety are interesting scaffolds for the development of novel antibacterial agents.