含吡啶(噻唑)甲基的哌嗪类化合物的合成及生物活性

采用活性基团拼接原理, 分别以2-氯-5-氯甲基吡啶和2-氯-5-氯甲基噻唑为原料, 经过氮烷基化和加成反应, 得到系列含吡啶甲基或噻唑甲基的哌嗪类化合物. 初步测试结果表明: 部分化合物表现出较弱的除草活性和杀豆蚜活性, 但对孑孓显示出较高的的杀灭活性, 其中4f在50 mg/L的浓度下对孑孓的杀死率可达100%.     

新型含哌嗪1,3,4-噻二唑酰胺衍生物的合成及其生物活性

以氨基硫脲和二硫化碳为起始原料,合成了15个新型的1,3,4-噻二唑衍生物(6a~6o),其结构经¹H NMR,¹³C NMR,IR,ESI-MS和元素分析表征。生物活性测试结果表明：大部分化合物对水稻白叶枯细菌有良好的抑制活性,其中,N-［5-(2,4-二氯苄基)硫醚］-1,3,4-噻二唑-2-(2-N-甲基哌嗪)-乙酰胺(6b)和N-［5-(4-三氟甲氧基苄基)硫醚］-1,3,4-噻二唑-2-(2-N-甲基哌嗪)-乙酰胺(6e)的EC₅₀分别为17.5 μg·mL^-1和19.8 μg·mL^-1; N-[5-(3-甲基苄基)硫醚)-1,3,4-噻二唑-2-(2-哌嗪)-乙酰胺(6k)在浓度为500 μg·mL^-1时,对烟草花叶病毒有一定的抑制活性。     

含喹喔啉杨梅素衍生物的合成及生物活性

利用活性拼接原理, 将喹喔啉引入到杨梅素结构中, 合成了一系列含喹喔啉基团的杨梅素新型衍生物. 采用浊度法测试了目标化合物的体外抑菌活性, 结果表明, 目标化合物对柑橘溃疡病菌(X. Citri)和水稻白叶枯病菌(X. Oryzae)均表现出较好的抑制活性. 目标化合物对柑橘溃疡病菌的抑制活性(EC₅₀)均优于对照药叶枯唑和噻菌铜(EC₅₀分别为54.85和61.13 μg/mL), 其中化合物4o抑制活性(EC₅₀=11.17 μg/mL)最优; 目标化合物对水稻白叶枯病菌的抑制活性EC₅₀均优于对照药叶枯唑和噻菌铜(EC₅₀分别为148.20和175.47 μg/mL), 其中化合物4f抑制活性(EC₅₀=34.49 μg/mL)最优. 采用半叶枯斑法测试了目标化合物的抗烟草花叶病毒(TMV)活性, 结果表明, 所有目标化合物在浓度为500 mg/L时均有一定的抑制作用.     

新型含吡啶环取代的吡唑肟醚类化合物的合成及生物活性研究

为了寻找新型高效低毒的农药先导化合物,通过N-吡啶基吡唑肟与2-氯-5-氯甲基吡啶的缩合反应,合成了一系列含吡啶环取代的吡唑肟醚类化合物.目标化合物的结构均经1H NMR,13C NMR和元素分析确证.初步生物活性试验结果表明,部分化合物具有一定的杀菌、杀虫和植物生长调节活性.如化合物5e在浓度为50 μtg/mL时对番茄早疫的抑制率为61.4％;化合物5j在浓度为50 μg/mL时对花生褐斑的抑制率为60.2％;化合物5i在浓度为500 μg/mL时对蚜虫表现出50.3％的杀死率;化合物5f在浓度为10 μg/mL时对黄瓜子叶生根表现出71.0％的促进生长作用.     

新型含噁二唑环的苯并噁/噻唑啉酮衍生物的合成、表征及生物活性

以邻氨基苯酚(硫酚)和尿素为起始原料, 经一系列反应, 合成出了30个新型含噁二唑环的苯并噁/噻唑啉酮衍生物(6). 利用IR、¹H NMR 和元素分析对新化合物4 和6 的结构进行了表征. 对所合成的目标化合物进行了抗癌、抗炎和免疫调节活性的筛选, 实验结果表明, 部分目标化合物具有弱的抗癌和免疫调节活性, 对TNF-α 和Cdc25B 磷酸酯酶均无抑制活性.     

Divergent Total Synthesis of Atisane‐Type Diterpenoids

Atisane‐type diterpenoids are the principal constituent of tetracyclic C₂₀‐diterpenoids, widely isolated from the plant kingdom with varying degrees of structural complexity and pharmacological activity. The tetracarbocyclic system with the unique bicyclo[2.2.2]octane skeleton of this natural product family has generated interest within the synthetic community. Divergent total synthesis is an effective tactic to synthesize several atisane‐type diterpenoids using structural interconversion from a common intermediate. This account summarizes the divergent total synthesis of atisane‐type diterpenoids.     

Discovery and Total Synthesis of Natural Cystobactamid Derivatives with Superior Activity against Gram‐Negative Pathogens

Antibiotic discovery and development is challenging as chemical scaffolds of synthetic origin often lack the required pharmaceutical properties, and the discovery of novel ones from natural sources is tedious. Herein, we report the discovery of new cystobactamids with a significantly improved antibacterial profile in a detailed screening of myxobacterial producer strains. Some of these new derivatives display antibacterial activities in the low‐μg mL⁻¹ range against Gram‐negative pathogens, including clinical isolates of Klebsiella oxytoca, Pseudomonas aeruginosa, and fluoroquinolone‐resistant Enterobacteriaceae, which were not observed for previously reported cystobactamids. Our findings provide structure–activity relationships and show how pathogen resistance can be overcome by natural scaffold diversity. The most promising derivative 861‐2 was prepared by total synthesis, enabling further chemical optimization of this privileged scaffold.     

Synthesis and Biological Activities of Phosphonothrixin

A novel herbicidal compound phosphonothrixin possessing a C-P bond, was isolated from the fermentation broth of Saccharothrix sp. ST-888. The biological activity against various weeds and total synthesis of phosphonothrixin are described herein.     

Total Synthesis and Biological Evaluation of Grassypeptolide A

Herein, we describe in full our investigations into the synthesis of grassypeptolide A ( 1 ) in 17 linear steps with an overall yield of 11.3 %. In particular, this work features the late‐stage introduction of sensitive bis(thiazoline) heterocycles and 31‐membered macrocyclization conducted at the sterically congested secondary amide site in superb conversion (72 % yield). Biological evaluation indicated that grassypeptolide A significantly inhibited cancer cell proliferation in a dose‐dependent manner. It induced cancer cell apoptosis, which was associated with increased cleavage of poly(ADP‐ribose) polymerase (PARP) and decreased expression of bcl‐2 and bcl‐xL. Furthermore, grassypeptolide A also caused cell cycle redistribution by increasing cells in the G1 phase and decreasing cells in the S and G2 phases. In addition, cell cycle arrest was correlated with downregulation of cyclin D and upregulation of p27 and p21.     

Redox Divergent Synthesis of Fawcettimine‐Type Lycopodium Alkaloids

A new approach for synthesis of fawcettimine‐type Lycopodium alkaloids is described. A divergent strategy was achieved by applying stereoselective Diels–Alder reaction followed by redox‐controlled elaboration. Eventually, (?)‐8‐deoxyserratinine, (+)‐fawcettimine, (?)‐lycopoclavamine‐A, (?)‐serratine, (?)‐lycopoclavamine‐B and (?)‐serratanidine were successfully accessed.     

5-氟尿嘧啶的三元环类化合物的缀合物的合成及其抗肿瘤活性

基于具有三元环状结构的化合物的广泛生理活性和氟尿嘧啶的抗癌作用机制,本文设计、合成并表征了一系列新型5-氟尿嘧啶（5-FU）的三元碳环缀合物及三元氧杂环缀合物。并对5-FU 的N-1和N-3位的选择性烷基化方法进行了系统研究,发现苄氧甲酰氧甲基保护基具有稳定性高、有效保护性好、制备方便、易于脱除等特点,适宜于在本类反应中应用。测试了所合成的新型5-FU三元环缀合物的体外抗肿瘤活性,化合物7、8、12、13显示了对人食管癌细胞Ec9706不同程度的抑制活性。     

新型含芳氧乙酸酯基三唑酮类化合物的合成及生物活性研究

通过芳氧乙酸与2-溴-4,4-二甲基-1-(1H-1,2,4-三唑-1-基)-3-戊酮反应, 合成了14个新型含芳氧乙酸酯基三唑酮类化合物. 所有化合物均经核磁、元素分析确证, 部分化合物进行了红外和质谱的测定. 生物活性测试表明部分化合物具有良好的生物活性.     

新型汉防己甲素衍生物的合成及其生物活性

以汉防己甲素为原料,经溴代反应制得关键中间体5-溴汉防己甲素(2); 2与硼酸衍生物经Suzuki反应合成了6个新型的汉防己甲素衍生物(4a~4f),其结构经¹H NMR, ¹³C NMR和ESI-MS表征。采用CCK-8法初步考察了4a~4f对人早幼粒白血病细胞(HL60)和人肺癌细胞(A549)的抑制活性;并采用MTT法对活性较好的化合物进行复筛。采用酶联免疫吸附法考察4a~4f对多种受体酪氨酸激酶的抑制活性。结果表明：4b, 4c和4e对HL60和A549有一定的抑制活性; 4b和4c对受体酪氨酸激酶FGFR1的抑制活性大于50%。     

新型含苯并噻唑基双酰胺衍生物的合成及其抗菌活性

以邻甲基苯甲酸和取代邻氨基苯甲酸为起始原料,设计并合成了10个未见文献报道的含苯并噻唑基双酰胺类衍生物,其结构经1H NMR,13C NMR,IR及元素分析表征。初步的抗菌活性测试结果表明,在500 mg.L-1浓度下部分化合物对黄瓜花叶病毒(CMV)有一定抑制作用。     

新型含2-取代-1,3-噻唑烷和噻唑环的亚胺类化合物的合成及生物活性

通过4-[(2-氰基亚胺基-1,3-噻唑烷-3-基)甲基]-2-氨基噻唑与取代苯甲醛的缩合反应, 合成了14个新型含2-取代- 1,3-噻唑烷和噻唑环的亚胺类化合物5. 所有化合物的结构均经1H NMR和元素分析确证, 并通过X射线单晶衍射分析测定了化合物5a的晶体结构. 初步生物活性试验结果表明, 部分目标化合物具有一定的杀菌活性和植物生长调节活性.     

Synthesis and Biological Activities of 6‐Hydroxyaurone Derivatives

A series of 6‐hydroxyaurone derivatives were synthesized in satisfactory yields and characterized by IR, ¹H NMR, ¹³C NMR, and HRMS or elemental analysis. The structure of compound 3e was further confirmed by X‐ray crystal analysis. Bioassay results indicated that some of the target compounds displayed moderate herbicidal activity against the dicotyledonous plant Brassica campestris L. at 100 µg·mL^?1, and some compounds also showed significant antiproliferative activity against tumor cell lines Hela, HepG‐2, and MCF‐7.     

Synthesis and Biological Activities of 1‐Azaaurone Derivatives

A series of 1‐azaaurone derivatives were designed and synthesized from 3,5‐dimethoxyaniline and 2‐chloroacetonitrile. Their structures were characterized by melting point, ¹H NMR, IR, and elemental analysis, as well as ¹³C NMR. The target compounds were evaluated for antitumor activities against human hepatocellular liver carcinoma cell line (HepG‐2) and human cervix carcinoma cell line (Hela) using methyl thiazolyl tetrazolium method. The results revealed that several 1‐azaaurones exhibited strong proliferation inhibition efficacy against HepG‐2 and Hela with an IC₅₀ range of 5.6–8.8 μg/mL without damaging normal cell.     

Solid‐phase Total Synthesis of (−)‐Apratoxin A and Its Analogues and Their Biological Evaluation

Two approaches for the solid‐phase total synthesis of apratoxin A and its derivatives were accomplished. In synthetic route A, the peptide was prepared by the sequential coupling of the corresponding amino acids on trityl chloride SynPhase Lanterns. After cleavage from the polymer‐support, macrolactamization of 10 , followed by thiazoline formation, provided apratoxin A. This approach, however, resulted in low yield because the chemoselectivity was not sufficient for the formation of the thiazoline ring though its analogue 33 was obtained. However, in synthetic route B, a cyclization precursor was prepared by solid‐phase peptide synthesis by using amino acids 13 – 15 and 18 . The final macrolactamization was performed in solution to provide apratoxin A in high overall yield. This method was then successfully applied to the synthesis of apratoxin analogues. The cytotoxic activity of the synthetic derivatives was then evaluated. The epimer 34 was as potent as apratoxin A, and O‐methyl tyrosine can be replaced by 7‐azidoheptyl tyrosine without loss of activity. The 1,3‐dipolar cycloaddition of 38 with phenylacetylene was performed in the presence of a copper catalyst without affecting the thiazoline ring.     

Calcium Phosphate Nanocarriers Dual‐Loaded with Bovine Serum Albumin and Ibuprofen: Facile Synthesis,Sequential Drug Loading and Sustained Drug Release

A simple and green strategy is reported for the preparation, drug loading, and release properties of a drug delivery system consisting of calcium phosphate (CP) nanocarriers dual‐loaded with bovine serum albumin (BSA) and hydrophobic drug ibuprofen (IBU). The sequential loading of BSA and IBU in calcium phosphate nanocarriers and in vitro simultaneous release of BSA and IBU are realized and investigated. In this method, BSA, which is used as a model protein drug, is encapsulated in situ in calcium phosphate nanocarriers. Subsequently, the typical hydrophobic drug IBU is loaded in the BSA/CP drug delivery system, forming the IBU/BSA/CP dual drug delivery system. The experiments reveal that the preloaded BSA not only reduces the cytotoxicity of calcium phosphate nanocarriers but also significantly improves the IBU drug loading capacity in calcium phosphate nanocarriers and greatly extends the duration of drug release. Thus, the as‐prepared IBU/BSA/CP dual drug delivery system is promising for drug delivery applications.