新型异噁唑衍生物的合成及其抗菌活性

5-乙酰胺甲基-3-[3-氟-4-(1-哌嗪基苯基)]异噁唑啉与氯乙酰氯反应制得中间体5-乙酰胺甲基-3-[3-氟-4-(4-氯乙酰基-1-哌嗪基苯基)]异噁唑啉(2);2与取代哌嗪或取代六氢吡啶反应合成了15个新型的异噁唑类衍生物(4a～4o),其结构经1H NMR和FAB-MS表征。初步的生物活性测试结果表明,4a～4o对金黄色葡萄球菌、藤黄八叠球菌、绿脓假单胞菌和肺炎克雷伯杆菌均有一定的抗菌活性。     

1-[3’-(4″-甲氧基苯基)-5’-甲基异噁唑-4’-甲酰基]-4-芳基氨基硫脲及其衍生物的合成

以3,5-二取代异噁唑-4-甲酰肼为基本原料制备关键中间体1-(3-对甲氧基苯基-5-甲基异噁唑-4-基)-4-芳基氨基硫脲(3a～3c);3在不同条件下经关环反应制得含有3,5-二取代异噁唑的2-芳氨基噻二唑(4a～4c),2-芳氨基噁二唑(5a～5c)和3-[3’-(4″-甲氧基苯基)-5’-甲基-异噁唑-4’-基)-4-芳基-1,2,4-三唑-5-硫酮(6a～6c);6与碘甲(乙)烷反应合成了4-芳基-5-[3’-(4″-甲氧基苯基)-5’-甲基异噁唑-4’-基]-3-甲(乙)硫基-1,2,4-三唑(7a～8c),其结构经1H NMR,IR,MS和元素分析表征,其中4,5,7和8未见文献报道。     

1-[3′-(4"-甲氧基苯基)-5′-甲基异噁唑-4′-甲酰基]-4-芳基氨基硫脲及其衍生物的合成

以3,5-二取代异噁唑-4-甲酰肼为基本原料制备关键中间体1-(3-对甲氧基苯基-5-甲基异噁唑-4-基)-4-芳基氨基硫脲(3a～3c);3在不同条件下经关环反应制得含有3,5-二取代异噁唑的2-芳氨基噻二唑(4a～4c),2-芳氨基噁二唑(5a～5c)和3-[3′-(4"-甲氧基苯基)-5′-甲基-异噁唑4′-基)-4-芳基-1,2,4-三唑-5-硫酮(6a～6c);6与碘甲(乙)烷反应合成了4-芳基-5-[3′-(4″-甲氧基苯基)-5′-甲基异噁唑-4′-基]-3-甲(乙)硫基-1,2,4-三唑(7a～8c),其结构经1H NMR,IR,MS和元素分析表征,其中4,5,7和8未见文献报道.     

含异噁唑环的新型2,5-二取代-1,3,4-噁二唑的合成及其杀菌活性

以取代异噁唑甲酸乙酯为起始原料,经取代、加成与环化反应合成了5个新型2-取代苯胺基-5-(取代异噁唑-4-基)-1,3,4-噁二唑(5a～5e),产率54.0％～86.7％,其结构经1H NMR,IR和元素分析表征.初步杀菌活性试验表明,5a,5c和5d对番茄灰霉病菌有很高的抑制作用,其活性高于对照药剂多菌灵.     

新型二唑类4-氨基喹唑啉衍生物的合成及其抗肿瘤活性

N-(3-氯-4-氟苯胺基)-7-(3-氯丙氧基)-6-甲氧基喹唑啉-4-胺与一系列取代二唑类化合物经取代反应合成了6个新型的二唑类4-氨基喹唑啉衍生物(3a~3f),其结构经1H NMR,13C NMR,IR及元素分析表征。用MTT法初步测定了3a~3f对前列腺癌细胞(PC-3)和人乳癌细胞(Bcap-37)的抑制率。结果表明:N-(3-氯-4-氟苯基)-6-甲氧基-7-{3-[5-(4-硝基苯基)-1,3,4-噻二唑-2-巯基]丙氧基}喹唑啉-4-胺和N-(3-氯-4-氟苯基)-7-{3-[5-(4-氯苯基)-1,3,4-噁二唑-2-巯基]丙氧基}-6-甲氧基喹唑啉-4-胺在用药量为10μmol·L-1时对PC-3的抑制率分别为66.8%和72.2%。     

氨基清除树脂辅助合成2-(7-氟-3-氧-3,4-2H-苯并[b][1,4]噁嗪-6-基)异吲哚1,3-二酮

采用氨基清除树脂辅助合成方法,由6-氨基-7-氟-4-取代基-3(4H)-酮与取代邻苯二甲酸酐在冰醋酸中加热反应制备了2-(7-氟-3-氧-3,4-2H-苯并[b][1,4]噁嗪-6-基)异吲哚-1,3-二酮类化合物,纯度86％～95％．其结构经^1H NMR,IR和MS表征。     

5-甲基-3-喹喔啉-2-基-4-乙氧羰基异噁唑及其衍生物的合成

以α-氯代喹喔啉-2-甲醛肟(3)与乙酰乙酸乙酯的钠盐经1,3-偶极环加成制得关键中间体5-甲基-3-喹喔啉-2-基-4-乙氧羰基异噁唑(4). 以化合物4为原料在不同条件下, 合成了一系列新的1,3,4-噁二唑啉(7), 1,2,4-均三唑的Mannich碱衍生物10a～10f, 11a～11f, 12a～12f. 化合物的结构经元素分析, IR, 1H NMR和MS确认, 并对其波谱性质进行了讨论.     

含吖啶基的新型二氧代氮杂茂并[3',4'-d]异噁唑衍生物的合成及其生物活性研究

在三乙胺的作用下,N-芳基-马来酰亚胺分别与α-氯代9-吖啶甲醛肟和N-(N,N-对二甲氨基苯基)-C-(9-吖啶基)取代硝酮发生1,3-偶极环加成反应,合成了13个未见文献报道的新型3-(9-吖啶基)-5-芳基-3a,6a-二氢-4,6-二氧代氮杂茂并[3',4'-d]异噁唑啉衍生物3a～3f和2-(N,N-对二甲氨基苯基)-3-(9-吖啶基)-5-芳基-3a,6a-二氢-4,6-二氧代氮杂茂并[3',4'-d]异噁唑烷衍生物4a～4g,其结构经1HNMR,IR和元素分析确证.并对化合物3和4进行了初步药物活性筛选,其对HL-60人白血病细胞生长具有不同程度的抑制作用,但当样品浓度为10μmol/L时,抑制率为0～35%(IC5050%).化合物3f和4g对细胞分裂周期磷酸酯酶Cdc25A具有抑制作用:当样品浓度为20μg/mL时,其抑制率分别为50.90%和51.22%.     

含哌啶的新型1,2,4-噁二唑类衍生物的设计合成及抗真菌活性研究

为了寻找新型高效的抗菌先导化合物,采用活性亚结构拼接法,设计合成了17个含哌啶的新型1,2,4-噁二唑类衍生物4a～4b和6a～6o,其结构经¹H NMR、¹³C NMR和高分辨质谱(HRMS)表征. N-(1-苯甲酰基哌啶-4-基)-4-(5-(三氟甲基)-1,2,4-噁二唑-3-基)苯甲酰胺(6e)结构由X射线单晶衍射法加以确证.抗菌活性测试结果表明:在浓度为3.13mg/L时, N-(1-乙酰基哌啶-4-基)-4-(5-(三氟甲基)-1,2,4-噁二唑-3-基)苯甲酰胺(6a)、N-(1-(环丙甲酰基)哌啶-4-基)-4-(5-(三氟甲基)-1,2,4-噁二唑-3-基)苯甲酰胺(6c)、6e、4-((4-(5-(三氟甲基)-1,2,4-噁二唑-3-基)苯甲酰胺基)甲基)哌啶-1-甲酸叔丁酯(4b)和N-((1-(苯甲酰基)哌啶-4-基)甲基-4-(5-(三氟甲基)-1,2,4-噁二唑-3-基)苯甲酰胺(6o)对大豆锈病(Phakopsora pachyrhiz)的抑制率分别为70%、82%、95%、78%和98%,优于Flufenoxa...     

新型二氧代氮杂茂并[3′,4′-d]异噁唑衍生物的合成

在三乙胺作用下,N-取代苯基马来酰亚胺与α-氯代对甲氧基苯甲醛肟发生1,3-偶极环加成反应,合成了6个新型3-(对甲氧基苯基)-5-芳基-3a,6a-二氢-4,6-二氧代氮杂茂并[3′,4′-d]异噁唑衍生物,其结构经1HNMR,IR和元素分析确证。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Copper catalyzed/mediated synthetic methodology for ebselen and related isoselenazolones

Scope of the copper catalyzed/mediated selenium-nitrogen coupling reaction has been studied for the synthesis of isoselenazolones. It is noticed that the 2-chloro, 2-bromo-, and 2-iodo-aryl amides substrates can be exploited in the selenium-nitrogen coupling reaction by employing 25-100 mol % of CuI/1,10-phenanthroline (L) and potassium carbonate as a base in DMF. Furthermore, electron rich 2-chloro-arylamides also underwent selenium-nitrogen coupling reaction to give biologically important selenium-nitrogen heterocycles. Also, copper-catalyzed selenium-nitrogen coupling reaction has been meticulously applied for the synthesis of diaryl diselenides having methoxy, amine, and amide functionality from respective aryl iodides in the presence of stoichiometric amount of succinimide as an external Se-N coupling partner.     

Knoevenagel condensation catalyzed by novel Nmm-based ionic liquids in water

A series of novel N-methyl morpholine (Nmm) based ionic liquids with 1,2-propanediol group were synthesized and used as catalysts for Knoevenagel condensation at room temperature in water. Under the effect of the catalyst, various aldehydes or aliphatic ketones could react with a wide range of activated methylene compounds well, including malononitrile, alkyl cyanoacetate, cyanoacetamide, β-diketone, barbituric acid, 2-arylacetonitrile and thiazolidinedione. Furthermore, most of the products could be separated just by filtrating and washing with water. Additionally, the catalyst is recyclable and applicable for the large-scale synthesis.     

Construction of polyheterocyclic spirotetrahydrothiophene derivatives via sulfa-Michael/aldol cascade reaction

A series of polyheterocyclic spirotetrahydrothiophene derivatives were obtained in moderate to excellent yields via a catalyst-free sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 under mild conditions. We also present the first asymmetric sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 with moderate to good enantioselectivities catalyzed by readily available chiral phase-transfer catalysts (PTCs).     

Suzuki-Miyaura reactions of the soluble guanylate cyclase inhibitor NS2028: a non-product specific route to C-8 substituted analogues

Both soluble guanylate cyclase (sGC) inhibitors ODQ 1 and NS2028 2 are synthesized via improved protocols. In the former case treating 3,4-dihydroquinoxalin-2(1H)-one oxime 8, which can be prepared in two steps from 1,2-benzenediamine, with 1,1′-carbonyldiimidazole (CDI) gives the dihydro-ODQ 10 that in the presence of KMnO₄ oxidises to give ODQ 1 in an overall yield of 46% starting from 1,2-benzenediamine. In the latter case, the synthesis affords NS2028 2 from 2-amino-4-bromophenol 3 in three steps with an overall yield of 85% and avoids the need for chromatography. Furthermore, Suzuki-Miyaura reaction conditions are described that enable the preparation of 8-aryl and 8-heteroaryl derivatives of NS2028 directly from NS2028 2. Finally, demethylation of the 8-(methoxyphenyl) substituted analogues afforded the 8-(hydroxyphenyl) derivatives 40-42. All new products are fully characterised.