一种有机锡化合物的合成、晶体结构、抗肿瘤及荧光性能

通过异烟肼和4-N,N-二羟乙基苯甲醛来合成一种席夫碱及其锡配合物,并通过核磁、元素分析以及X-射线单晶衍射来进行结构表征。该平面构型的席夫碱采取二齿配位模式,其中的-C=N-在配位后由反式变为顺式。晶体结构数据以及荧光光谱中的显著红移现象表明锡配合物中的π-共轭体系通过配位反应得以延展。体外细胞毒性数据表明,席夫碱配体及其锡配合物对于A-549,MCF-7和Hela等肿瘤细胞的生长抑制活性要强于顺铂。还通过紫外可见光谱及荧光光谱初步研究了两种化合物与DNA的相互作用,结果表明锡配合物可能通过共价结合来导致DNA双螺旋链变形,而席夫碱分子中的氢键效应及其长平面结构可能会阻碍其嵌入DNA双螺旋链。     

烷氧基三联吡啶钌配合物的合成、结构及其与DNA相互作用

制备了2种含长基链的烷氧基三联吡啶和2,2''-联吡啶配位的钌配合物（Ru-Cl、Ru-NCMe）,通过质谱、核磁和单晶X射线衍射分析等进行了表征。从它们的晶体结构可以发现Ru-Cl配合物中第6个配位点为Cl-离子,在Ru-NCMe配合物中的第6个配位点为乙腈分子中的N原子。通过紫外可见吸收光谱和荧光光谱研究了这2种配合物与多种氨基酸和DNA的作用,发现这种长烷基链和刚性配位平面的配合物与DNA具有明显的特异性识别效应,进一步研究发现它们与DNA以插入方式和静电作用结合,实验与理论模拟结果一致。     

新型三足席夫碱稀土配合物的合成,表征及与DNA的作用

合成了新型三足席夫碱配体(L)和它的5种稀土配合物. 通过元素分析、摩尔电导、热重分析、红外光谱测试技术对配合物的结构进行了表征. 结果表明,该配合物 [LnL(NO3)2]NO3·H2O(Ln:La,Sm,Eu,Gd,Y)是按照L∶ Ln=1∶ 1配位,并且有2个硝酸根参与了配位,金属离子采取8配位的模式. 采用荧光光谱法研究了这5种席夫碱配合物与DNA的相互作用. 实验结果表明,配合物均可与DNA发生相互作用,而且相互作用为插入方式.     

N-((喹啉-8-基)亚甲基)水杨酰肼Sn(Ⅳ)/Ag(Ⅰ)配合物的合成、晶体结构和DNA相互作用（英文）

合成并通过单晶衍射、元素分析及红外光谱表征了配合物[Sn(L)Ph_2Cl]·0.25CH_3OH (1)和[Ag(HL)(NO_3)]·CH_3OH (2)(HL=N-(喹啉-8-亚甲基)水杨酰肼)的结构。单晶衍射结果表明,配合物1的Sn(Ⅳ)与配体中的1个ON2供体,1个氯离子,2个苯环上的碳原子配位,形成扭曲的八面体结构。配合物2的中心金属离子与配体中的ON_2供体和1个双齿硝酸根配位,拥有扭曲的四方锥配位构型。此外,荧光光谱表明配合物与DNA的相互作用强于配体。     

配合物[Pd(L-tyr)2]·0.5H2O的晶体结构、稳定性及其与DNA作用研究

合成了配合物[Pd(L-tyr)2]·0.5H2O单晶(L-tyr-为酪氨酸根).配合物属于单斜晶系,P2(1)空间群.L-tyr-的羧基氧原子和氨基氮原子与Pd(Ⅱ)离子配位,形成两个五元螯合环的平面结构.配合物分子之间存在配位螯合环-配位螯合环的弱相互作用、苯酚环-苯酚环之间的π-π堆积作用以及水分子与配体之间的氢键作用.水溶液中配合物的累积稳定常数为1017数量级,表明配体与离子形成较强的配位共价键.配合物与鱼精DNA作用的紫外光谱、CD光谱和荧光光谱表明,两者之间有较强的相互作用,并以插入作用方式为主.     

吡嗪缩氨基硫脲Ni(Ⅱ)/Co(Ⅲ)配合物的合成、结构和DNA结合性质（英文）

合成并通过单晶衍射、元素分析及红外光谱表征了配合物[Ni(L)(OAc)](1)和[Co(L)_2]Cl·4CH_3OH(2)的结构(HL为2-乙酰-3-甲基吡嗪-N-(4-氟苯基)缩氨基硫脲)。单晶衍射结果表明,配合物1中,Ni(Ⅱ)离子中心与缩氨基硫脲配体中的NNS供体和1个单齿醋酸根配位,形成扭曲的平面四边形配位构型;在配合物2中,Co(Ⅲ)离子中心与2个三齿缩氨基硫脲配体配位,拥有扭曲的八面体配位构型。此外,荧光光谱表明配合物1和2与DNA的相互作用强于配体。     

顺二羰基(三齿N-配体)铑(Ⅰ)配合物的分子内取代反应

报道了3种不同结构的三齿N-配体以及与铑形成的顺二羰基配合物.研究表明,正方平面顺二羰基铑配合物在遇热条件下,其配体中未参与配位的授体N原子可取代它的一个端羰基而形成新的三齿配位结构.而在CO气氛下,三齿配位结构回到二齿配位状态.正方平面铑配合物的这一特殊分子内取代可逆反应过程,对于研究这类配合物结构、性能及催化作用均有重要的意义.非正方平面顺二羰基铑配合物则不发生上述分子内取代反应.利用IR和XPS对上述反应进行了表征.     

N-(2-丙酸)-芳甲酰腙二对甲基苄基锡配合物的合成、晶体结构及生物活性

二对甲基苄基二氯化锡分别与N-(2-丙酸)-对硝基苯甲酰腙及N-(2-丙酸)-对叔丁基苯甲酰腙反应,合成了2个取代二苄基锡配合物(C1、C2),通过元素分析、IR、UV-Vis、1H NMR、13C NMR、119Sn NMR、X射线单晶衍射以及热重分析等表征了配合物结构。测试了配合物对癌细胞H460、HepG2、MCF7以及正常人体肝细胞HL7702的体外抑制活性;在Tris-HCl缓冲溶液中,以EB作为荧光探针,用荧光光谱法初步研究了配合物与小牛胸腺DNA的相互作用。结果表明:配合物C1、C2对3种癌细胞都有较好的抑制作用,配合物C2对HL7702的细胞毒性远小于C1;配合物C1、C2与小牛胸腺DNA作用均是插入结合作用所致。     

红光材料双β-二酮铕配合物的合成、结构与发光性质

通过分子设计,合成了一种新颖的双β-二酮配体N-正丁基-3,6-二(1,3-丁二酮基)咔唑(H2L)及其铕配合物.单晶X衍射测定了H2L的晶体结构.配体和配合物的红外光谱和电子光谱表明,Eu3 与H2L发生螯合配位.配体的荧光光谱是宽带的蓝色发光,属H2L*→H2L跃迁,而配合物的溶液荧光光谱除了配体的蓝光带外,还有611nm处的Eu3 的特征红光,属5D0→7F2跃迁带;配合物的光致发光光谱只有613nm处为Eu3 的特征红光,属5D0→7F2跃迁带,峰形尖锐,单色性好,表明该配合物为一种潜在的红色发光材料.     

两个基于苯并咪唑席夫碱的镍(Ⅱ)配合物的合成、晶体结构和抑菌活性（英文）

在甲醇体系中,分别将苯并咪唑席夫碱HL~1和HL~2与高氯酸镍进行配位反应得到2个结构类似的镍配合物[Ni(L~1)_2]·2H_2O(1)和[Ni(L~2)_2]·2H_2O(2)(HL~1=N-(benzimidazol-2-ylethyl)-5-chlorosalicylideneimine,HL~2=N-(Benzimidazol-2-ylethyl)-5-bromosalicylidenei-mine),并用元素分析、红外光谱、紫外-可见光谱和单晶X射线衍射对其结构进行了表征。结构分析表明:两个配合物均属于单斜晶系,C2/c空间群,Ni(Ⅱ)与来自2个席夫碱配体的4个氮原子和2个氧原子配位,形成八面体结构。配合物中的氢键将配合物1和配合物2分别连接成二维和三维网络结构。选取金黄色葡萄球菌和大肠杆菌作为菌种,研究了2个席夫碱配体和2个配合物的抑菌能力。     

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.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

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.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

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.