血吸虫病化学治疗的研究——ⅩⅪⅤ.5-[2-(5-硝基呋喃基-2)-1-取代乙烯基]-1,3,4-噁二唑酮及其1,3,4-噁二唑衍生物的合成

本文报道硝基呋喃乙烯基-1,3,4-噁二唑及其酮类衍生物44个的合成。关键中间体α-取代β-(5-硝基呋喃基-2)丙烯酰彤魄仿照文献已知方法制备的,然后分别与光气或溴化腈作用生成相应的1,3,4-噁二唑衍生物Ⅰ,Ⅱ。经感染日本血吸虫病小白鼠的预防和治疗试验,发现化合物Ⅰ_1具有显著的抗血吸虫作用,并试用于家犬的血吸虫病,证明有一定的疗效。但效果不及呋喃丙胺,故未作临床观察。     

血吸虫病化学治疗的研究——Ⅳ.β-(5-硝基-2-呋喃)丙酰胺类及其α,β-二溴取代衍生物的合成

本文报道38个β-(5-硝基-2-呋喃)丙酰胺及其α,β-二溴取代衍生物的合成。这类化合物的制备是以相应的β-(5-硝基-2-呋喃)丙烯酰胺类化合物(Ⅰ)进行催化氢化或与溴加成而得。经动物筛选发现β-(5-硝基-2-呋喃)丙烯酰胺类的丙烯双键以氢饱和以后生成丙酰胺类化合物(Ⅱ),对感染日本血吸虫病的小白鼠完全失去治疗或预防作用。而以溴饱和双键的α,β-二溴化合物(Ⅲ)则仍然有较显著的杀虫作用。其中尤以β-(5-硝基-2-呋喃)-α,β-二溴丙酰异丙胺(Ⅲ₁₁)和β-(5-硝基-2-呋喃)-α,β-二溴丙酰甘氨酸乙酯(Ⅲ₂₄)最为显著,后者曾试用于临床,证明有一定疗效。     

抗血吸虫病化合物:β-(5-硝基-2-呋喃)-丙烯酰二胺类衍生物的合成

本文报道70个β-(5-硝基-2-呋喃)-丙烯酰二胺类衍生物的合成。对感染日本血吸虫病小白鼠进行治疗和预防初筛的结果,发现有54个化合物具有不同程度的抗虫作用。其中以反式β-(5-硝基2-呋喃)-N-(2-哌啶乙基)丙烯酰胺盐酸盐(I₁₃,F-30385)及其盐基呋喃双胺(I₁₄,F-30642)杀虫作用最强,均已试用于临床,后者疗效较好,副作用较轻。     

1,3,4-噁二唑衍生物的合成方法及其抗菌活性研究进展

目的:综述1,3,4-噁二唑衍生物的合成方法及其抗菌活性的研究进展,为开发高效低毒药物提供参考。方法:以"1,3,4-噁二唑""抗菌活性""1,3,4-oxadiazole derivatives""Antimicrobial bioactivity"等为关键词,组合查询1990-2014年中国知网、万方、Pub Med、Science Direct等数据库中有关1,3,4-噁二唑衍生物方面的文献,就其合成方法及抗菌活性等方面的内容进行归纳与总结。结果:共查询到相关文献80余篇,有效文献35篇。目前,除传统合成方法外,还可采用催化法、无溶剂法、聚合物载体法和微波辐射法等新的合成方法制备1,3,4-噁二唑衍生物。经过不同结构改造的含金刚烷基、脂肪酸、磺酰、氰基、吡啶基、苯骈咪唑类的1,3,4-噁二唑衍生物对革兰阴性菌、革兰阳性菌、真菌等均具有一定的抗菌活性。结论:1,3,4-噁二唑是药物化学发展至关重要的先导化合物,其衍生物对致病微生物具有良好的抑制和杀灭作用。分析不同结构改造的1,3,4-噁二唑衍生物的抗菌活性,有助于寻找更加高效、新颖的抗菌药物。     

血吸虫病化学治疗的研究——ⅩⅩⅩⅦ.β-(5-硝基-4-溴-2-呋喃)-及β-(4,5-二溴-2-呋喃)丙烯酰胺及其酯类的合成

本文报道β-(4,5-二溴-2-呋喃)-及β-(5-硝基-4-溴-2-呋喃)丙烯酰胺及其酯类衍生物26个的合成。动物筛选结果表明;化合物Ⅲ₆,Ⅲ₈和Ⅲ₁₃对感染日本血吸虫小白鼠有明显的治疗作用。化合物Ⅱ₆有较明显的预防作用。     

血吸虫病化学治疗的研究——ⅩⅩⅩⅣ.α-氯-β-(5-硝基-2-呋喃)丙烯酰胺类及其乙烯噁二唑类衍生物的合成

β-(5-硝基-2-呋喃)丙烯酰胺类及其乙烯杂环类化合物均有显著的抗日本血吸虫作用,其中以β-(5-硝基-2-呋喃)丙烯酰异丙胺(F-30066)和5-[(5-硝基-2-呋喃)乙烯]-1,3,4-(口恶)二唑(F-30809)为最强。前者已生产多年,曾广泛应用于临床治疗日本血吸虫病。为了试图提高疗效,降低副作用,作者等合成了具有下列通式(Ⅰ)和(Ⅱ)的两类衍生物,以观察其抗虫活性。     

吲哚-1,3,4-噁二唑类衍生物的合成及其体外抗肿瘤活性研究

目的 合成吲哚-1,3,4-噁二唑类衍生物,并进行体外抗肿瘤活性研究。方法 以吲哚-3-甲酰肼为起始原料,通过[4+1]环加成反应、水解反应、缩合反应得到目标化合物。采用MTT法测试目标化合物对HeLa、SCG-7901和MDA-MB-231细胞的体外抗肿瘤活性。采用克隆形成实验考察化合物6f对SCG-7901细胞增殖的影响。采用Annexin V-APC/PI双染法检测化合物6f对SCG-7901细胞凋亡和坏死的影响。采用DAPI染色法检测化合物6f对SCG-7901细胞凋亡核染色质形态学的影响。采用DCFH-DA染色法检测化合物6f对SCG-7901细胞中活性氧含量的影响。结果 合成了15个吲哚-1,3,4-噁二唑类衍生物,其结构经¹H-NMR、¹³C-NMR和HR-ESI-MS确证。部分化合物表现出良好的抗肿瘤活性,其中化合物6f对HeLa、SCG-7901和MDA-MB-231 3种肿瘤细胞株均表现出明显的抗增殖作用,且具有一定的选择性。进一步研究表明,化合物6f以浓度相关的方式促进细胞产生活性氧,抑制细胞增殖,诱导细胞凋亡。结论 部分吲哚-1,3,4-噁二唑类衍生物表现出良好的抗肿瘤活性,为该类化合物的进一步抗肿瘤活性研究提供思路。     

3-芳基-5-三氮唑基-噁二唑衍生物HIF-1抑制剂的设计、合成与构效关系研究

目的 设计、合成3-芳基-5-三氮唑基-噁二唑类缺氧诱导因子-1(hypoxia-inducible factor 1，HIF-1)抑制剂。方法 以化合物8为先导，将吡唑基替换为1,2,3-三氮唑基，并对噁二唑和苯环取代基等进行改造，获得全新的3-芳基-5-三氮唑基-噁二唑衍生物。结果 所合成的大部分化合物均显示出较优的HIF-1抑制活性，化合物10n活性最强，IC₅₀值为0.59 μmol·L^-1，其作用机制是抑制HIF-1α蛋白表达，且能显著抑制SKOV3细胞的侵袭和迁移。结论 设计、合成的3-芳基-5-三氮唑基-噁二唑类衍生物是全新的HIF-1抑制剂，显示出抑制肿瘤迁移的效应。     

2-苯基-5-吡啶基-1,3,4-噁二唑类化合物的合成及黄嘌呤氧化酶抑制活性

目的 设计合成2-苯基-5-吡啶基-1,3,4-噁二唑类化合物,并对其黄嘌呤氧化酶抑制活性进行初步评价。方法 以对羟基苯甲酸甲酯为原料,经烃化、肼解、环合等反应合成目标化合物。以非布司他为阳性对照药,采用牛源的黄嘌呤氧化酶对目标化合物的抑制活性进行评价。结果 共合成了15 个未见文献报道的目标化合物,结构经核磁共振氢谱、飞行时间质谱和红外光谱确证。目标化合物均表现出一定的黄嘌呤氧化酶抑制活性,其中化合物 4m（IC₅₀=1.04 µmol·L^-1）活性最好,但低于阳性对照药非布司他（IC₅₀=0.024 µmol·L^-1）。结论 2-苯基-5-吡啶基-1,3,4-噁二唑类化合物作为新型黄嘌呤氧化酶抑制剂,其构效关系值得进一步研究。     

硝基呋喃乙烯噁二唑类抗血吸虫病新药的研究

呋喃烯唑(S-72055)经动物实验和临床观察,证明对日本血吸虫病有较好的疗效,为了寻找更好的药物,本文以β-(5-硝基-2-呋喃)丙烯酰胺肟为原料,合成了若干系列呋喃烯唑的类似物。同时,为了研究乙烯桥在呋喃烯唑结构中的重要性,又以5-硝基-2-呋喃甲酰胺肟为原料,合成了呋喃烯唑的去乙烯桥的类似物。动物实验结果,证明(口恶)二唑环上5位酰胺基或5位烃氨甲基的存在,一般可使化合物具有抗血吸虫作用,而呋喃烯唑的去乙烯桥类似物,几乎没有活性。     

Synthesis and in vitro anti-Helicobacter pylori activity of 2-[(chlorobenzyl)thio]-5-(5-nitro-2-furyl)-1,3,4-thiadiazoles

A new series of 2-[(chlorobenzyl)thio]-5-(5-nitro-2-furyl)-1,3,4-thiadiazoles (6a–h) were synthesized and evaluated by the disc diffusion method against Helicobacter pylori. Four compounds which exhibited strong anti-H. pylori activity at concentration of 8–32 μg/disc (average of inhibition zone >20 mm) were further tested against 20 clinical isolates of H. pylori at lower concentrations. The averages of inhibition zone diameters indicated that all selected compounds exhibit better anti-H. pylori activity profile against clinical isolates of H. pylori with respect to standard drug metronidazole. Compound 6c, containing the 3-chlorobenzylthio moiety, was the most potent compound tested.     

Synthesis and antibacterial activity of N-[5-chlorobenzylthio-1,3,4-thiadiazol-2-yl] piperazinyl quinolone derivatives

A series ofN-[5-(chlorobenzylthio)-1,3,4-thiadiazol-2-yl] piperazinyl quinolone derivatives (4a-1) have been synthesized by reaction of piperazinyl quinolones with 5-chloro-2-(chloroben-zylthio)-1,3,4-thiadiazoles. Their structures were confirmed by elemental analysis, IR and NMR spectra. The antibacterial activities of4a-1 against a variety of Gram-positive and Gram-negative bacteria were determined. Several compounds showed a good antibacterial activity against Gram-positive bacteria among which, compound 4e with a 2-chlorobenzylthio moiety in ciprofloxacin derivative, exhibited high activities againstStaphylococcus aureus andStaphylococcus epidermidis (MIC=0.06 μg/mL). The structure-activity relationship (SAR) study revealed that the position of chlorine atom on benzyl moiety would dramatically affect the antibacterial activities of the synthesized compounds.     

Synthesis and biological evaluation of novel 2-[substituted acetly]-amino-5-alkyl]-amino-5-alkyl-1,3,4-thiadiazoles

Sixteen novel 2-substituted acetyl amino-5-alkyl-1,3,4-thiadiazole were synthesized and screened for their pharmacological activities. A few of the compounds namely 11, 12 and 16 showed anti-inflammatory activities comparable to phenylbutazone. Compound 12 also showed significant non-specific spasmolytic activity. Diuretic activity of compound 15 at a dose level of 90 mg/kg p.o. was two fold higher compared to 50 mg/kg p.o. of furosemide. Comparable diuresis was also produced by compounds 9, 10 and 16. Division of Medicinal Chemistry, Department of Pharmaceutical Sciences, Dr. Harisingh Gour Vishwavidyalaya [Formerly University of Saugor] Sagar 470003 (MP), India     

影响噻二唑合成的相关因素研究

配料比,时间、温度等相关因素是生产2-巯基-5-甲基-1,3,4噻二唑的重要环节。本文研究了相关因素对噻二唑合成收率的影响,通过改变配料、时间、温度等条件使合成收率达55％以上。     

Synthesis and biological evaluation of novel benzyl piperazine derivatives of 5-(5-nitroaryl)-1,3,4-thiadiazoles as Anti-Helicobacter pylori agents

Background and the purpose of the study

Helicobacter pylori is recognized as the main cause of gastritis and gastroduodenal ulcers and classified as class 1 carcinogen pathogen. Different 1,3,4-thiadiazole derivatives bearing 5-nitroaryl moiety have been shown considerable anti- H. pylori activity. In attempt to find new and potent derivatives of described scaffold, a new series of 1-(substituted benzyl)-4-(5-(5-nitroaryl-2-yl)-1,3,4-thiadiazol-2-yl)piperazine derivatives were synthesized and evaluated against three metronidazole-resistant isolates of H. pylori using paper disk diffusion bioassay test.

Methods

The title compounds were prepared through the reaction of 1-(5-(5-nitroaryl-2-yl)-1,3,4-thiadiazol-2-yl) piperazine 5a-b and substituted benzyl chloride in DMF. The inhibitory activity of the new derivatives 6a-q against three metronidazole-resistant isolates of H. pylori was evaluated by the disc diffusion method and compared with the commercially available standard drug metronidazole.

Results and discussion

The results of SAR study indicated that the potency and anti-H. pylori activity profile of synthesized derivatives is mainly attributed to the substituted nitroaryl moiety at the C-5 position of 1,3,4-thiadiazole ring. Most of 1,3,4-thiadiazole derivatives bearing 5-nitrofuran moiety at C-5 position of central thiadiazole ring, demonstrated more promising anti-H. pylori than the 5-nitrothiophen counterpart.

Conclusion

The most potent nitrofuran derivative containing 3-methoxybenzyl piperazine pendant at the C-2 position of 1,3,4-thiadiazole ring (compound 6i), demonstrated strong anti-H. pylori potential at studied concentrations 100-25 μg/disk (IZD > 20 mm) against all studied metronidazole- resistant isolates of H. pylori.     

Mixed Dopaminergic/Serotonergic Properties of Several 2-Substituted 4-[2-(5-Benzimidazole)ethyl]-1-arylpiperazines

A series of substituted 4-[2-(5-benzimidazole)ethyl]-arylpiperazines was synthesized by introducing different substituents into position 2 of benzimidazole ring of 4-[2-(N,N-di-n-propyl-amino)ethyl]-1,2-diaminobenzenes. They were evaluated for in vitro binding affinity at the D₁ and D₂ dopamine and 5-HT_1A serotonin receptors using synaptosomal membranes of the bovine caudate nuclei and hippocampi, respectively. Tritiated SCH 23390 (D₁ receptor-selective), spiperone (D₂ receptor selective) and 8-OH-DPAT (5-HAT_1A receptor selective) were employed as the radioligands. Only compound 6 expressed a moderate binding affinity at the dopamine D₁ receptor, while the remaining ligands were inefficient or weak competitors of [³H]SCH 23390. Compound 12 was an absolutely inactive competitor of all three radioligands. Also, compound 7 was an inefficient displacer of [³H]-8-OH-DPAT. Compound 19 with a K_i value of 3.5 nM was the most potent competitor of [³H]spiperone and compound 13 (K_i = 3.3 nM) was the most efficient in displacing [³H]-8-OH-DPAT from the 5-HAT_1A serotonin receptor. Ligands 5, 6, 8–11 , and 13–20 expressed mixed dopaminergic/serotonergic activity in nanomolar range of concentrations with varying affinity ratios which strongly depended on the properties of the substituents introduced into position 2 of benzimidazole ring of the parent compounds.     

血吸虫病化学治疗的研究 ⅩⅩⅩⅥ.4-苯基(或烯丙基)-5-(吡嗪-2)-1,2,4-三唑-3-硫酮衍生物的合成

本文报导28个4-苯基(或烯丙基)-5-(吡嗪-2)-1,2,4-三唑-3-硫酮衍生物的合成。这类化合物的合成是以吡嗪甲酸乙酯与水合肼反应得2-吡嗪甲酰肼,再与不同的异硫氰酸酯作用后,在2N氢氧化钠溶液中环合而得Ⅱ或Ⅲ,然后经烷化、酰化及Mannich反应,分别制得相应的化合物。其中Ⅲ₁和Ⅲ₂对感染日本血吸虫小白鼠有明显肝移作用。     

5-Nitroimidazole-based 1,3,4-thiadiazoles: heterocyclic analogs of metronidazole as anti-Helicobacter pylori agents

A series of 5‐nitroimidazole‐based 1,3,4‐thiadiazoles were prepared and tested for antibacterial activity against Helicobacter pylori. The anti‐H. pylori activity of target compounds along with the commercially available antimicrobial metronidazole was evaluated by comparing the inhibition‐zone diameters determined by the paper disc diffusion bioassay. From our bioassay results against 20 clinical isolates it is evident that piperazinyl, 4‐methylpiperazinyl, 3‐methylpiperazinyl, and 3,5‐dimethylpiperazinyl analogs ( 6a , 6b , 6e , and 6f , respectively) and pyrrolidine derivative 7 had strong activity at 0.5 µg/disc (average of inhibition zone >20 mm) while metronidazole had no activity at this dose. Compound 6f containing the 3,5‐dimethylpiperazinyl moiety at the 2‐position of the 5‐(1‐methyl‐5‐nitro‐1H‐imidazol‐2‐yl)‐1,3,4‐thiadiazole skeleton was the most potent compound tested at low concentrations.