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1.
王宁  火跃芳  石云 《化学世界》2013,(12):734-736,739
以四氢呋喃(THF)为溶剂,采用易得的5-氨基-1,2,4-二噻唑-3-硫酮(氢化黄原素)和N,N-二甲基甲酰胺二甲基缩醛为原料合成((二甲基氨基-亚甲基)氨基)-3 H-1,2,4-二噻唑-3-硫酮(DDTT)。通过对影响收率的关键因素进行研究,找到了最佳反应条件:n(氢化黄元素)∶n(N,N-二甲基甲酰胺二甲基缩醛)为1∶1.1,25℃下反应6h,收率达90%。合成工艺操作方便,纯化简单,收率高。  相似文献   

2.
供应信息     
<正>(1)上海志浦化工有限公司供应:2-甲基-3-甲硫基呋喃、吡嗪基乙硫醇、反,反-2,4-癸二烯醛、反,反-2,4-壬二烯醛、双(2-甲基-3-呋喃基)二硫醚、4-甲基-4-巯基-2-戊酮、3-甲基-2-丁硫醇、2-甲基四氢呋喃-3-酮、硫代乳酸、2-乙酰基吡啶、2,3,5,6-四甲基吡嗪、4-甲基-5-乙酰氧乙基噻唑、2,4,5-三甲基噻唑、四氢噻吩-3-酮、香兰素、3-巯基-2-丁醇、二糠基二硫、甲基(2-甲基-3-呋喃基)二硫醚、2-乙酰基噻唑、呋喃酮乙酸酯、2-乙酰基吡嗪、4-甲基-5-羟乙基噻唑、二丙基二硫醚、2,3,5-三甲基吡嗪、糠基  相似文献   

3.
纳米氮化硅粉体的大分子改性剂表面修饰研究   总被引:2,自引:0,他引:2  
从分子设计的角度合成了一种新型的大分子表面改性剂(LMPB-g-MAH):采用溶液聚合法将极性单体马来酸酐(MAH)接枝到低分子量的聚丁二烯液体橡胶(LMPB)分子长链中,并用其对纳米氮化硅粉体进行表面修饰;对合成的大分子表面改性剂、改性前后的纳米氮化硅粉体,运用FT-IR、TEM、TGA、粒径分析、沉降实验等方法进行了表征.实验结果表明:马来酸酐已经接枝到低分子量的聚丁二烯液体橡胶分子长链中;当大分子表面改性剂的接枝率为9%~11%、用量为10%~12%、反应温度为65℃、反应时间为3 h时,表面修饰后的纳米氮化硅粉体颗粒粒径减小,有效阻止了纳米颗粒的团聚.  相似文献   

4.
以7-氨基-(1-甲基-1H-四唑-5-硫甲基)-3-头孢烯-4-羧酸二苯甲酯(7-DAMC)为原料经缩合和甲氧基化等一系列反应制备得到甲氧头孢关键中间体7β-氨基-7α-甲氧基-3-(1-甲基-1H-四唑-5-硫甲基)-3-头孢烯-4-羧酸二苯甲酯(7-MAC)。实验结果表明合成中间体7-对甲苯硫亚氨基-3-(1-甲基-1H-四唑-5-硫甲基)-3-头孢烯-4-羧基酸二苯甲酯(7-DTMC)的较佳条件为:n(7-DAMC)∶n(TSC)∶n(环氧丙烷)=1∶3.5∶40,反应时间为3h,反应温度为30℃;产品7-MAC的较佳合成条件为:n(甲醇)∶n(无水AlCl3)∶n(PPh3)∶n(7-DTMC)=230∶1.5∶2∶1,反应温度25℃,PPh3插入反应时间15h,甲氧基化反应时间5h,收率54.17%,HPLC纯度99.15%。产品结构均经1H-NMR和IR表征认证。  相似文献   

5.
5-甲氧基-4-甲基-1,2,4-三唑-3-酮是氟酮磺隆的关键中间体。以硫氰酸钾和氯甲酸甲酯为起始原料,经三步反应得到目的产物。(1)以甲基异丁酮为溶剂,硫氰酸钠和氯甲酸甲酯、甲醇反应制得1,3-二甲基硫代亚胺二羟酸酯;(2)以上产物与水合肼环化制得5-甲氧基-2,4-二氢-3H-1,2,4-三唑-3-酮;(3)经硫酸二甲酯甲基化制得目的产物5-甲氧基-4-甲基-2,4-二氢-3H-1,2,4-三唑-3-酮(MMT)。分别考察了催化剂对1,3-二甲基硫代亚胺二羟酸酯,缚酸剂对5-甲氧基-2,4-二氢-3H-1,2,4-三唑-3-酮和pH值对5-甲氧基-4-甲基2,4-二氢-3H-1,2,4-三唑-3-酮收率的影响。产物总收率55.61%。  相似文献   

6.
刘利军  郭建国 《化学世界》2004,45(5):251-254
以3-苯硫基丙块1为原料经5步反应合成了(Z)-5-甲基-3苯硫甲基-5-氢呋喃-2-酮8和(Z)-5-甲基-3-苯硫甲叉基4,5-二氢呋喃-2-酮9。合成的关键步骤是在三甲基氯硅烷(TMSCl)/NaI/H2O/CH3CN体系中5-苯硫基-3-戊炔-2-酮3一步完成的碘氢化和去共轭反应。  相似文献   

7.
唑草酮的合成   总被引:1,自引:0,他引:1  
李梅芳  韩邦友 《现代农药》2010,9(3):28-30,33
改进了除草剂唑草酮的合成工艺,以4-氯-2-氟苯肼为原料,经氨基腙合成、光气环合制成取代芳基三唑啉酮,再经二氟甲基化、硝化、加氢还原合成中间体1-(5-氨基-4-氯-2-氟苯基)-3-甲基-4-二氟甲基-1H-1,2,4-三唑啉-5-酮,重氮化后与丙烯酸乙酯反应,经后处理得唑草酮。  相似文献   

8.
根据文献报道的抗抑郁药噻萘普汀钠的合成方法,设计了一条新的合成路线。本论文以N-(3-氯-6,11-二氢-6-甲基-苯二氮卓[c,f][1,2]噻氮卓-11-酮)-S,S-二氧化物(5,简称三环酮)为起始原料,经还原、氯化、胺化、水解反应制得噻萘普汀钠(1),总收率为48.5%。产物结构经过IR和1HNMR确证。  相似文献   

9.
隋颖 《广州化工》2013,(16):127-128
采用化学共沉淀法合成Fe3O4纳米颗粒,用葡萄糖酸对磁性纳米颗粒表面进行了修饰,并利用扫描电子显微镜(SEM)、傅立叶转变红外光谱仪(FT-IR)、X-射线衍射(XRD)对修饰前后的Fe3O4纳米颗粒进行了表征,实验结果表明:磁性纳米颗粒粒径分布均匀、单分散性好,改性后其表面具有相应的官能团。  相似文献   

10.
《农药》2017,(9)
综述氟噻唑吡乙酮及其中间体的合成工艺路线。中间体硫代甲酰胺是以三氟甲基吡唑为原料合成,收率为64%。溴代1-(5-(2,6-二氟苯基)-4,5-二氢异唑-3-基)乙酮的收率为83.7%。氟噻唑吡乙酮以1-(2-(5-甲基-3-(三氟甲基)-1H-吡唑-1-基)乙酰基)哌啶-4-硫代甲酰胺为关键中间体经缩合、卤代、格氏等反应合成。  相似文献   

11.
为了筛选更为高效、广谱的杀菌剂,以二氨基硫脲为原料,与正丁酸合成中间体5-丙基-4-氨基-2,4-二氢-1,2,4-三唑-3-硫酮,再与取代的芳香醛在酸催化下反应合成5个席夫碱化合物,并用1H NMR、IR和元素分析对化合物进行了结构表征。  相似文献   

12.
In the present investigation, new hydrazinecarbothioamides 4–6 were synthesized by reaction of 4-(4-X-phenylsulfonyl)benzoic acids hydrazides (X= H, Cl, Br) 1–3 with 2,4-difluorophenyl isothiocyanate and further these were treated with sodium hydroxide to obtain 1,2,4-triazole-3-thione derivatives 7–9. The reaction of 7–9 with α-halogenated ketones, in basic media, afforded new S-alkylated derivatives 10–15. The structures of the synthesized compounds have been established on the basis of 1H-NMR, 13C-NMR, IR, mass spectral studies and elemental analysis. The antioxidant activity of all compounds has been screened. Hydrazinecarbothioamides 4–6 showed excellent antioxidant activity and 1,2,4-triazole-3-thiones 7–9 showed good antioxidant activity using the DPPH method.  相似文献   

13.
The reaction of 5-(1-adamantyl)-4-ethyl or allyl-1,2,4-triazoline-3-thione with formaldehyde solution and various 1-substituted piperazines yielded the corresponding N-Mannich bases. The newly synthesized N-Mannich bases were tested for in vitro inhibitory activities against a panel of Gram-positive and Gram-negative bacteria and the yeast-like pathogenic fungus Candida albicans. Six compounds showed potent antibacterial activity against one or more of the tested microorganisms, while two compounds exhibited moderate activity against the tested Gram-positive bacteria. None of the newly synthesized compounds were proved to possess marked activity against Candida albicans. The oral hypoglycemic activity of six compounds was determined in streptozotocin (STZ)-induced diabetic rats. Four compounds produced significant strong dose-dependent reduction of serum glucose levels, compared to gliclazide at 10 mg/kg dose level (potency ratio > 75%).  相似文献   

14.
The acid dissociation constants (Ka) of a series of 3,4-diaryl-1H-1,2,4-triazole-5-thiones ( 1 ) were determined and were found to correlated linearly with Hammett substituent constants; log Ka = 1.06 σx − 11.01. Such a result indicates that 1 exists essentially in one tautomeric form namely the thione form. Reactions of 1 with hydrazonoyl chlorides 2 gave the thiohydrazides 5 . Similiar reaction of 3-phenyl-1H(4H)- 1,2,4-triazole-5-thione 1g with 2a gave the thiohydrazide 5h which was converted into 1,3,5-triphenyl-1,2,4-triazolo[3,4-c]-1,2,4-triazole ( 9 ). The latter was also prepared from 3-phenyl-5-methylthio-4H-1,2,4-triazole ( 6 ) and 2a . The mechanism of the reaction of 1 with 2 is discussed.  相似文献   

15.
Several new quinazolin-4-one containing oxadiazolin-5-thione moieties were synthesized and evaluated for their antibacterial activity. Esterification of 2-substituted phenyl-3-carboxyalkyl-methyl-3,4-dihydroquinazolin-4-ones (I) with absolute ethyl alcohol in the presence of sulfuric acid afforded the corresponding esters (II). Hydrazinolysis of (II) with hydrazine hydrate in ethanol gave the acid hydrazides (III). Refluxing (III) with equimolar amounts of potassium hydroxide and slight excess of carbon disulfide afforded the corresponding oxadiazolin-5-thione derivatives (IV). The thiones undergo Mannich reaction using a formaldehyde/secondary amines mixture whereby the 4-substituted amino-methyl derivatives (V) were obtained. Microanalysis, IR, NMR spectra were used to elucidate the structures of the newly synthesized compounds. All the designed compounds were tested for their antibacterial activity. The morpholino derivatives showed an encouraging antibacterial activity.  相似文献   

16.
为了筛选出新的高活性化合物,以二氨基硫脲与有机羧酸为原料,回流反应生成中间体4-氨基-5-取代-1,2,4-三唑硫酮,再与羧酸在POCl3的催化下合成了3,6-双取代1,2,4-三唑并[3,4-b]-1,3,4-噻二唑新化合物。目标化合物通过IR、元素分析和1H NMR对其结构进行了表征。并初步测定了该化合物对5种植物病原菌(烟草赤星病、马铃薯干腐病、小麦赤霉病、番茄早疫病、西瓜枯萎病)的杀菌活性,结果表明此类化合物对所测菌种具有良好的杀菌、抑菌作用。  相似文献   

17.
Thiatriazoles V. On the Reaction of Isothiocyanates with Thiatriazole Derivatives The reaction of 1,2,3,4-thiatriazoles with alkyl and aryl isothiocyanate proceeded differently. Methylisothiocyanate furnished a 2:1 product with 5-amino-1,2,3,4-thiatriazole. Arylisothiocyanates reacted under the same conditions to the known thiapentalenes 6 . 5-Alkyl- and 5-arylamino-1,2,3,4-thiatriazoles gave 5-substituted 1,2,4-thiadiazol-3-thions 8 . Similar the hydrazones of 1,2,3,4-thiatriazole reacted with isothiocyanate to form the hydrazones of 1,2,4-thiadiazole-3-thione 10 . 4-Dimethylamino-pyridine is a necessary catalyst for the selectivity of these reactions.  相似文献   

18.
A new Schiff base, 4-(4-hydroxysalicylidenamino)-3-hydrazino-5-mercapto-1,2,4-triazole (4HSAHMT), and novel Schiff base oligomers of 4-salicylidenamino-3-hydrazino-5-mercapto-1,2,4-triazole (SAHMT), 4-(2-hydroxynaphthylidenamino)-3-hydrazino-5-mercapto-1,2,4-triazole (2HNAHMT), 4-(4-hydroxysalicylidenamino)-3-hydrazino-5-mercapto-1,2,4-triazole (4HSAHMT) and 4-(5-bromosalicylidenamino)-3-hydrazino-5-mercapto-1,2,4-triazole (BrSAHMT) were synthesized via oxidative polymerization using NaOCl as the oxidant. The structures of the oligomers were supported by FT-IR, UV–Vis, 1H-NMR, and 13C-NMR techniques. The compounds were further characterized by solubility tests, TG–DTA, and elemental analysis. The molecular weight distribution parameters of the compounds were determined by the size exclusion chromatography (SEC). According to SEC, the number average molecular weight (M n ) values of O-SAHMT, O-BrSAHMT, O-4HSAHMT and O-2HNAHMT were 2,700, 2,100, 2,700 and 1,000 g mol?1, respectively. The weight losses of O-SAHMT, O-BrSAHMT, O-4HSAHMT and O-2HNAHMT were 73, 76, 80 and 54 %, respectively, at 1,000 °C. TG analyses showed that the synthesized oligomers were stable toward thermal decomposition. The synthesized oligomers were converted to metal complexes with salts of VO(IV) and Cu(II). The doped and undoped electrical properties of oligomers and oligomer–metal complexes were determined by the four-point probe technique at room temperature and atmospheric pressure.  相似文献   

19.
7-溴乙氧基黄酮与3-取代-4-氨基-1,2,4-三唑-5-硫醇类化合物缩合反应得到7-(4-氨基-1,2,4-三唑-5-)硫乙氧基黄酮,为了增加其脂溶性,将该类化合物进一步与乙酸酐回流反应12 h,得到的化合物不是预期的7-(3-取代-4-乙酰氨基-1,2,4-三唑-5-)硫乙氧基黄酮衍生物,而是7-[3-取代-4-(2-乙酰氧基)-乙亚氨基-1,2,4-三唑-5-]硫乙氧基黄酮,分别用红外、核磁共振氢谱及碳谱、质谱和元素分析对这4个乙酰化产物的结构进行了确证。以清除超氧自由基、羟自由基、亚硝基自由基和2,2-二苯基-1-苦味酰基自由基的活性及总还原能力为指标,测定比较了4个7-(3-取代-4-氨基-1,2,4-三唑-5-)硫乙氧基黄酮化合物及其意外乙酰化产物的体外抗氧化活性。结果表明,在测定浓度下,乙酰化衍生物7-[3-对甲氧苯基-4-(2-乙酰氧基)-乙亚氨基-1,2,4-三唑-5-]硫乙氧基黄酮较其前体抗氧化活性强。  相似文献   

20.
通过石蜡膜控制沉淀离子扩散速率,采用尿素水解制备镧化合物,对其进行热重分析确定焙烧温度,运用XRD、TEM等表征手段对其进行表征,物相分析表明焙烧产物主要成分为La5O7NO3,粒径约为40 nm。合成两性表面活性剂对纳米镧化合物进行表面修饰,使其能稳定分散于液体石蜡基础油中。以液体石蜡为润滑油基础油,添加基础油质量0.5%的表面活性剂修饰后的纳米镧极压抗磨剂,结果表明,极压性提高33.33%、磨损性减小20%左右。  相似文献   

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