环戊甲基苯并咪唑衍生物的合成、表征及抑菌活性

环戊甲基苯并咪唑衍生物的合成、表征及抑菌活性;环戊甲基苯并咪唑衍生物;合成;微波辐射;抑菌活性     

α-萘基环己基甲基酮仿生合成新方法

α-萘基环己基甲基酮仿生合成新方法;四氢叶酸辅酶;苯并咪唑甲基碘盐;Grignard试剂;α-萘基环己基甲基酮;仿生合成     

新型苯并咪唑取代的丙烯腈衍生物的催化合成

从邻苯二胺出发,合成了2-腈甲基苯并咪唑,对2-腈甲基苯并咪唑与醛的Knoevenagel缩合反应催化剂进行了优选,研究表明,吗啡啉/乙酸是催化2-腈甲基苯并咪唑与芳香醛Knoevenagel缩合反应的良好催化剂;在吗啡啉/乙酸催化下,合成了新型的双苯并咪唑丙烯腈衍生物和3-吲哚-2-苯并咪唑丙烯腈衍生物;将2-腈甲基苯并咪唑经过碱性水解,酯化,得到苯并咪唑乙酸乙酯,后者经过次序Knoevenagel缩合/分子内酯交换高产率地得到了新型的苯并咪唑取代的香豆素衍生物。     

α-萘基丙酮的一种新合成方法

α-萘基丙酮的一种新合成方法;二甲基-(α-萘甲基)苯并咪唑盐;Grignard试剂;(α-萘基)丙酮;合成     

2-苯并咪唑乙酮肟醚衍生物的合成及其抑菌活性

设计并合成了6个新型的2-苯并咪唑乙酮肟醚衍生物,产率57.1%~72.6%,其结构经1HNMR,IR和元素分析表征。初步杀菌活性测试表明,部分化合物对黄瓜菌核病菌有较好的抑制活性。     

2-芳基(烷基)-苯并咪唑-1-乙酰腙衍生物的合成及抗肿瘤活性研究

在2-取代苯并咪唑环上引入酰腙基团,合成了一系列含有苯并咪唑环的酰腙衍生物(c1-18),采用IR,1H NMR和MS对其结构进行了表征,采用MTT法对目标物抑制4种癌细胞增殖活性进行了测试。其中N-(2,4-二羟基苯亚甲基)-2-[2-(2,4-二氯苯基)-1H-苯并咪唑-1-基]乙酰腙(c2)和N-(2-羟基苯甲烯基)-2-[2-(4-硝基苯基)-1H-苯并咪唑-1-基]乙酰腙(c10)对所测试的肿瘤细胞均表现出明显的抑制活性(IC50=2-21μM)。     

苯并异喹啉酮衍生物的合成及其荧光性质

苯并异喹啉酮衍生物的合成及其荧光性质;苯并咪唑苯并异喹啉酮;萘酰亚胺;荧光量子产率;亲核取代反应;合成     

2种苯并咪唑衍生物在微波作用下的固相合成

2种苯并咪唑衍生物在微波作用下的固相合成;固相合成;微波辐射;苯并咪唑衍生物     

2-[5'-CH3(H)-苯并咪唑-2'-亚甲硫基]-5-取代-1,3,4-噁二唑的合成及生长素活性

以邻苯二胺(或4-甲基邻苯二胺)及一氯乙酸为原料,在酸性条件下,合成2-氯甲基苯并咪唑及2-氯甲基-5-甲基苯并咪唑;以取代羧酸为原料经酯化、肼解、再与CS2在氢氧化钾溶液中反应,合成10种2-巯基-5-取代-1,3,4-噁二唑;将2种2-氯甲基-5-取代-苯并咪唑与10种2-巯基-5-取代-1,3,4-噁二唑在氢氧化钠溶液中反应,合成14种2-[5’-CH3(H)-苯并咪唑-2’-亚甲硫基]-5-取代-1,3,4-噁二唑衍生物。借助红外光谱、核磁共振氢谱和元素分析对化合物结构进行表征。初步生长素活性测试结果表明,所合成的化合物对小麦芽鞘和绿豆发芽有着不同程度的生长调节作用。     

嘌呤2位卤素取代衍生物的合成

嘌呤2位卤素取代衍生物的合成;嘌呤;重氮化;合成;杀菌活性     

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%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

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.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

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.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).