基于真菌14α-去甲基化酶的非氮唑类抗真菌先导化合物的设计、合成及其体外抗真菌活性研究

基于真菌羊毛甾醇14α-去甲基化酶(CYP51)活性位点的三维结构设计并合成了新型四氢异喹啉类抗真菌先导化合物. 体外抗真菌活性研究显示: 设计的先导化合物具有较好的抗真菌活性. 其中化合物5f和5g对于5种测试菌的抗真菌活性强于或相当于对照药物氟康唑. 先导分子通过与靶酶活性腔氨基酸残基的非共价键结合产生抗真菌作用, 避免与血红素辅基Fe原子发生配位结合, 为一类具有新作用机理的非氮唑类抗真菌先导化合物. 本研究为抗真菌药物研究提供了新的结合方式及结构类型.     

N-{2-氯-5-[3-甲基-2,6-二氧-4-三氟甲基-2,3-二氢嘧啶-1(6H)-基]苯基}酰胺类化合物的合成及除草活性

为了寻找高效、安全的除草活性化合物, 合成了12个全新的N-{2-氯-5-[3-甲基-2,6-二氧-4-三氟甲基-2,3-二氢嘧啶-1(6H)-基]苯基}酰胺类化合物, 其化学结构经IR, ¹H NMR, LC/MS和元素分析确证. 初步生物活性测定结果表明, 该类化合物具有一定的除草活性, 如7a, 7b, 7c, 7g, 7h, 7i, 7k和7l在有效成分75 g/hm²剂量下, 茎叶处理对苘麻(Abutilon theophrasti)、刺苋(Amaranthus spinosus)等阔叶杂草具有良好的除草活性, 其抑制率达100%.     

5,7-二甲基-1,2,4-三唑并[1,5-a]嘧啶-2-甲酰腙类化合物的合成与生物活性

以5-氨基-1H-1,2,4-三唑-3-羧酸为起始原料, 设计合成了13个新型的5,7-二甲基-1,2,4-三唑并[1,5-a]嘧啶-2-甲酰腙类化合物, 通过¹H NMR, MS和元素分析对所合成的化合物进行了结构表征. 初步的生物活性测试结果表明, 所合成的化合物均表现出不同程度的除草及杀菌活性, 其中化合物4b, 4h和5m的活性较好, 在50 mg/L浓度下对水稻纹枯病菌的抑制率达90 %以上.     

双核钌-DMBA双芳香炔化合物的合成和电化学性质

在弱碱性条件下,双核钌（Ⅲ）配合物Ru₂（DMBA）₄（NO₃）₂（DMBA=tetrakis-N,N''-dimethylbenzamidinate）与不同芳香炔反应（其中芳香基团包括：NAP^me,N-甲基-1,8-萘二甲酰亚胺;NAP^iso,N-异丙基-1,8-萘二甲酰亚胺;Naphth,萘;Ant,蒽）,制备了相应的端基炔取代配合物trans-Ru₂（DMBA）₄（C₂Ar）₂（Ar=NAP^me,1;NAP^iso,2;Naphth,3;Ant,4）。利用X射线晶体衍射测定了它们的结构。所有化合物的Ru-Ru 键长处于单键范围（0.245 0~0.249 1 nm）,它们均是抗磁性物质。进一步通过¹H NMR和UV-Vis-NIR光谱进行了表征。电化学研究表明,所有化合物显示出与芳香基团有关的2个可逆的单电子氧化还原过程（包括一个氧化过程和一个还原过程）。     

反式十氢萘类液晶的合成

以6-烷基-2-十氢萘酮为原料, 经格氏试剂与羰基的加成、脱水、还原及异构化合成系列反式十氢萘类单体液晶 1～12, 产率9.9%～80.8%, 2, 3的产率高于文献值. 结构经过IR, ¹³C NMR, MS鉴定, 并探讨了化合物的相变行为特点和碱催化条件下十氢萘构象异构化的历程.     

双核钌-DMBA双芳香炔化合物的合成和电化学性质

在弱碱性条件下,双核钌(III)配合物Ru₂（DMBA）₄（NO₃）₂（DMBA=tetrakis-N,N''-dimethylbenzamidinate）与不同芳香炔反应（其中芳香基团包括：NAP^me,N-甲基-1,8-萘二甲酰亚胺;NAP^iso,N-异丙基-1,8-萘二甲酰亚胺;Naphth,萘;Ant,蒽）,制备了相应的端基炔取代配合物trans-Ru₂（DMBA）₄（C₂Ar）₂（Ar=NAP^me,1;NAP^iso,2;Naphth,3;Ant,4）。利用X射线晶体衍射测定了它们的结构。所有化合物的Ru-Ru键长处于单键范围（0.2450~0.2491 nm）,它们均是抗磁性物质。进一步通过¹H NMR和UV-Vis-NIR光谱进行了表征。电化学研究表明,所有化合物显示出与芳香基团有关的2个可逆的单电子氧化还原过程（包括一个氧化过程和一个还原过程）。     

含肉桂酰胺类化合物的合成及α-糖苷酶抑制活性

合成了4个未见报道的含肉桂酰胺类化合物9a～9b, 初步评价了它们的α-糖苷酶抑制活性. 这些化合物均具有α-糖苷酶抑制活性, 是一类结构新颖的α-糖苷酶抑制活性化合物, 其中, 化合物9b和9c的活性高于阳性对照药物阿卡波糖.     

2-[2-(烷氧羰基苯氧羰基)苯氧基]-4,6-二甲氧基嘧啶类化合物的合成及其除草活性研究

为了寻找高效、安全、经济的除草活性化合物, 设计并合成了9个新的2-[2-(烷氧羰基苯氧羰基)苯氧基]-4,6-二甲氧基嘧啶类化合物, 其化学结构经IR, ¹H NMR, LC/MS和元素分析确证. 初步生物活性测定结果表明, 该类化合物在有效成份2250 g/ha剂量时, 对苘麻(Abutilon theophrasti)、稗草(Echinochloa crus-galli)、狗尾草(Setaria viridis)等都具有良好的除草活性, 抑制率达90％以上. 其中5b, 5e, 5h在187.5 g/ha剂量时, 仍具有良好的除草活性, 抑制率达90％以上.     

芳醛-N-(1-苯基-1H-四唑-5-巯基)乙酰腙的微波合成及其晶体结构

在微波辐射下快速、高产率地合成了一系列含有四唑环的酰腙类化合物, 并对其进行了元素分析、红外以及核磁共振氢谱和碳谱表征. 对化合物4a的无色晶体进行了X射线晶体衍射. 结果表明, 该晶体属三斜晶系, 空间群P-1, V＝0.80070(38) nm³, Z＝2, D_c＝1.404 g•cm^－3, a＝0.7382(1) nm, b＝0.9992(2) nm, c＝1.1535(2) nm, α＝81.41(2)°, β＝85.72(2)°, γ＝72.21(2)°, 分子结构呈反式构型, 通过分子间氢键组装成二聚体. 生物活性测试发现部分化合物具有抗菌活性.     

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.     

Design,synthesis and antifungal activities in vitro of novel tetralin compounds

Novel chiral tetralin compounds were designed and synthesized, and their antifungal activities in vitro were tested. The results showed that all of target compounds had potent antifungal activities, and were stronger than that of control compounds tetrahydroisoquinolines. The binding model of lead molecules in the active site of CYP51 of Candida albicans showed that lead compound specifically interacted with the amino acids residues in the active site, without binding with the heme of CYP51, which was different from azole antifungal drugs. The present study might afford a novel lead molecule to develop non-azole CYP51 inhihitars of fungi.     

Design,synthesis and antifungal activity of carbazole derivatives

The incidence of invasive fungal infections is increasing rapidly. Clinically available antifungal agents suffer from limited efficacy and severe resistance. There is an urgent need to discover antifungal lead compounds with novel chemical scaffold. On the basis of our previously identified tetrahydrocarbazole antifungal leads, the structure-activity relationship was further explored by modifying the scaffold and the side chains. Several targeted compounds showed potent activity against Candida species. Particularly, compound 13i showed better antifungal activity than the lead compound, which can be used as a good starting point for further optimization.     

New triazole derivatives containing substituted 1, 2, 3-triazole side chains: Design,synthesis and antifungal activity

In order to discover new generation of triazole antifungal agents,a series of novel antifungal triazoles were designed and synthesized by structural simplification of our previously identified triazole-piperdine-heterocycle lead compounds.Several target compounds showed good antifungal activity with a broad spectrum.In particular,compound 7l was highly active against Candida albicans and Candida glabrata.Moreover,compound 7l showed potent in vivo antifungal efficacy in the Caenorhabditis elegans-C.albicans infection model.     

Synthesis and fungicidal activity study of novel daphneolone analogs with 2,6-dimethylmorpholine

A series of novel daphneolone analogs was designed and synthesized on the basis of natural product 1,5-diphenyl-2-penten-1-one(I) from Stellera chamaejasme L. as lead compound, whereby 2,6-dimethylmorpholine moiety was introduced to replace 1-phenyl group. Their structures were confirmed by IR,1H NMR, and HRMS(ESI) or elemental analysis,13 C NMR for some representative compounds. The two isomers of target compounds were separated and identified by NOESY technique and chemical method.All of the synthesized compounds have been evaluated for anti-plant pathogenic fungi activities. The results showed that some compounds exhibited moderate to good antifungal activities against tested fungi at the concentration of 50 mg/L. Among them, compound 7d, with a 4-bromine-substituted phenyl group and cis-2,6-dimethylmorpholine moiety, displayed best activity with an EC50 of 23.87 mmol/L against Valsa mali, superior to lead compound I. In addition, preliminary structure–activity relationship analysis indicated that, between two isomers of target compounds, the antifungal activities of the isomer with cis-2,6-dimethylmorpholine were better than the trans-isomer.     

Purification and Partial Characterization of Bacillomycin L Produced by Bacillus amyloliquefaciens K103 from Lemon

Bacillus amyloliquefaciens K103 isolated from a lemon sample was used as a biocontrol agent to suppress Rhizoctonia solani Kühn and other fungal plant pathogens. Two antifungal compounds were purified from the culture broth using acid precipitation, gel permeation chromatography, and reversed-phase high-performance liquid chromatography. Matrix-assisted laser desorption ionization-time of flight mass spectrometry analysis indicated that the antifungal compounds were two isomers similar to bacillomycin L. One of the predominant active fractions was subjected to quadrupole time-of-flight mass spectrometry and amino acid analysis to determine its structural characteristics, revealing that the antifungal compound with a molecular mass of 1,034.5464 was identical to bacillomycin L. This is the second report of lemon microflora producing bacillomycin L or any antifungal compound, suppressing the growth of R. solani Kühn. Meanwhile, the study provided insights into the enormous potential of food microbial resources and bacillomycin L antibiotics in biological control and sustainable agriculture.     

Synthesis and biological evaluation of novel triazole derivatives as antifungal agents

A series of 1-(benzylamino)-2-(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-l-yl)propan-2-ols compounds were synthesized and evaluated for their antifungal activities in vitro.The results showed that compounds 6A and 6B exhibited good antifungal activity.Compound 6A8 showed the strongest antifungal activity,which was significantly higher than that of the lead compounds and positive-control drugs Fluconazole and Itraconazole.In particular,the antifungal activity of compound 6A8 against Candida albicans and Candida krusei(MIC80 both at 0.00097μg/mL) was 515 and 64 times that of Fluconazole,respectively.The structure-activity relationships of the synthesized compounds were discussed,and the docking model of the target compounds with fungal lanosterol 14α-demethylase (CYP51) was analyzed.     

Synthesis,docking and ADMET prediction of novel 5-（（5-substituted- 1 -H- 1,2,4-triazol-3-yl ） methyl ）-4, 5,6,7-tetrahydrothieno [ 3,2-c ] pyri- dine as antifungal agents

A novel series of 5-((5-substituted-1H-1,2,4-triazol-3-yl)methyl)-4,5,6,7-tetrahydrothieno[3,2-c]pyridines 5(a–i) has been synthesized from thienopyridine hydrazide, substituted aromatic nitriles using 4-dimethylaminopyridine(DMAP) as a catalyst under microwave irradiation and evaluated for their in vitro antifungal activity. Compound 5g is found to be more potent against Candida albicans when compared with miconazole. Docking study of the newly synthesized compounds was performed, and results showed good binding mode in the active site of fungal enzyme P450 cytochrome lanosterol 14 ademethylase. ADMET properties of synthesized compounds were also analyzed and showed good drug like properties. The results of in vitro antifungal activity, docking study and ADMET prediction revealed that the synthesized compounds have potential antifungal activity and can be further optimized and developed as a lead compound.     

Synthesis,structural, spectral,computational, docking and biological activities of Schiff base (E)-4-bromo-2-hydroxybenzylidene) amino)-N-(pyrimidin-2-yl) benzenesulfonamide from 5-bromosalicylaldehyde and sulfadiazine

The newly synthesized, characterized, and theoretically investigated Schiff base compound (E)-4-bromo-2-hydroxybenzylidene) amino)-N-(pyrimidin-2-yl) benzenesulfonamide (5BRSDA). Sulfadiazine and 5-bromosalicylaldehyde Schiff-base were the building blocks for the new compound. We were surprised by the variety in the structure of the results. By employing density functional theory (DFT), researchers were able to analyze the new compound molecular properties, geometric optimization, vibrational, frontier molecular orbitals, and energy evaluation. In addition, disc well diffusion was used to test the compounds antibacterial and antifungal properties. As compared to free ligands, the compound had a more potent pathogenic effect on the tested microbes, according to the findings. An in-depth molecular docking study on 1NTA provided new information about the inhibitory effects it has on pathogenic microbes. When compared to a literature survey, comparative analysis revealed that the titled compound had higher antibacterial and antifungal activity.     

Curvicollides A-C: new polyketide-derived lactones from a sclerotium-colonizing isolate of Podospora curvicolla (NRRL 25778)

Curvicollides A-C (1-3) have been obtained from cultures of an isolate of Podospora curvicolla (NRRL 25778) that colonized a sclerotium of Aspergillus flavus. The structures of these compounds were elucidated by analysis of one- and two-dimensional NMR data. The lead compound (1) showed antifungal activity against A. flavus and Fusarium verticillioides. [structure: see text]     

Design,Synthesis and Antifungal Evaluation of Novel Pyrylium Salt In Vitro and In Vivo

Nowadays, discovering new skeleton antifungal drugs is the direct way to address clinical fungal infections. Pyrylium salt SM21 was screened from a library containing 50,240 small molecules. Several studies about the antifungal activity and mechanism of SM21 have been reported, but the structure–activity relationship of pyrylium salts was not clear. To explore the chemical space of antifungal pyrylium salt SM21, a series of pyrylium salt derivatives were designed and synthesized. Their antifungal activity and structure-activity relationships (SAR) were investigated. Compared with SM21, most of the synthesized compounds exhibited equivalent or improved antifungal activities against Candida albicans in vitro. The synthesized compounds, such as XY10, XY13, XY14, XY16 and XY17 exhibited comparable antifungal activities against C. albicans with MIC values ranging from 0.47 to 1.0 μM. Fortunately, a compound numbered XY12 showed stronger antifungal activities and lower cytotoxicity was obtained. The MIC of compound XY12 against C. albicans was 0.24 μM, and the cytotoxicity decreased 20-fold as compared to SM21. In addition, XY12 was effective against fluconazole-resistant C. albicans and other pathogenic Candida species. More importantly, XY12 could significantly increase the survival rate of mice with a systemic C. albicans infection, which suggested the good antifungal activities of XY12 in vitro and in vivo. Our results indicated that structural modification of pyrylium salts could lead to the discovery of new antifungal drugs.