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951.
Zaesung No Shi Yong Ryu Seong-Kie Kim Jong Woong Ahn Bok Ju Song Keun Jae Kim 《合成通讯》2013,43(5):887-892
Thermal or base-promoted conversion of 5′-O-TBDMS-3′-O-(1H-imidazole-1-thiocarbonyl)thymidine (1) afforded 5′-O-TBDMS-2,3′-anhydro-thymidine (2), a pivotal intermediate for the transformation of the 3′-hydroxy group of 2′-deoxyribonucleosides, in high yield. 相似文献
952.
Abstract A series of novel Mahkoside A derivatives was synthesized, and their in vitro cytotoxic activities were evaluated against the human cancer cell line Ec‐9706. A Preliminary structure–activity relationship study showed compounds 7 and 8 have obvious cytotoxic activities (IC50: 30.0 and 12.5 µg · mL?1, respectively). 相似文献
953.
A series of cholesterylated thiogalactosides L1 –L6 the cell targeting ligands for gene delivery to hepatocytes, was synthesized. Related poly(ethylene glycol) chain was used as a bridge for the attachment of galactoside on one hydroxyl end, while the other hydroxyl end was linked with cholesterol. This design provided an effective entry for the synthesis of a poly(ethylene glycol) compound with the hepatocyte targeting. 相似文献
954.
Recyclable Siloxy Serine Organocatalyst for the Direct Asymmetric Mannich Reactions in Ionic Liquids
Fui-Fong Yong 《合成通讯》2013,43(9):1293-1300
A recyclable siloxy-L-serine organocatalyst has been developed to catalyze the asymmetric direct three-component Mannich reactions in ionic liquid hmim[PF6], furnishing the β-amino carbonyl scaffold in high enantio- and diastereoselectivities. The direct Mannich reaction between a selection of aromatic aldehydes and ketones resulted in good yields and high enantioselectivities.
955.
Macrocycles consisting of two tris(phenylene ethynylene) (or tri-PE) units connected via two flexible linkers adopt an ‘unfolded’ conformation that is converted into a folded conformation upon introducing intramolecular hydrogen bonding interaction. These foldable macrocycles are capable of forming inclusion charge transfer (CT) complex with electron-deficient small aromatics. 相似文献
956.
New well-defined monodisperse oligocarbazoles-functionalized anthracenes An-OCZn (n = 1, 2, 3) have been synthesized through Suzuki cross-coupling reaction of the brominated oligocarbazoles and 9,10-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracene. They show good solubility in organic solvents, including dichloromethane, chloroform, toluene, ethyl acetate, and tetrahydrofuran. It should be noted that, in the case of An-OCZn, the formation of the excimer based on anthracene unit is suppressed completely due to the introduction of oligocarbazoles in 9,10-position of anthracene so that an intense blue-emitting has been afforded. In addition, the obtained An-OCZn exhibit good electrochemical and thermal stabilities. Thus, the oligocarbazoles-functionalized anthracenes can be a class of promising candidates for novel blue-emitting materials employed in OLEDs or related devices. 相似文献
957.
Jing‐Tao Shi Chun‐Sheng Zhou Yong‐Liang Liu Zhi‐Guo Fang Rui‐Li Zhao Li‐Li Xu Ke‐Fen Yue 《无机化学与普通化学杂志》2013,639(1):187-192
Two coordination polymers (CPs), {[Zn2(BMB)(5‐AIPA)2] · 2H2O}n( 1 ) and [Zn(BMB)(5‐NIPA)]n( 2 ) {BMB = 1, 4‐bis[(2‐methyl‐imidazol‐1‐yl)methyl]benzene, 5‐AIPA = 5‐aminoisophthalic acid, 5‐NIPA = 5‐nitroisophthalic acid}, were synthesized under hydrothermal conditions. Compound 1 displays a 2D double‐layer structure, which is packed into a 3D supramolecule by interlayer hydrogen bonds and π–π stacking interactions. Compound 2 displays a threefold interpenetrating 3D network, which is composed of left‐handed helical chains and two types of meso‐helical chains along different directions. 相似文献
958.
Xiao‐Ying Cheng Ming‐Fang Wang Zheng‐Yin Yang Yong Li Zeng‐Chen Liu Qiao‐Xia Zhou 《无机化学与普通化学杂志》2013,639(5):832-841
The Schiff base ligand, 1‐phenyl‐3‐methyl‐5‐hydroxypyrazole‐4‐methylene‐8′‐quinolineimine, and its CuII, ZnII, and NiII complexes were synthesized and characterized. The crystal structure of the ZnII complex was determined by single‐crystal X‐ray diffraction, indicating that the metal ions and Schiff base ligand can form mononuclear six‐coordination complexes with 1:1 metal‐to‐ligand stoichiometry at the metal ions as centers. The binding mechanism and affinity of the ligand and its metal complexes to calf thymus DNA (CT DNA) were investigated by UV/Vis spectroscopy, fluorescence titration spectroscopy, EB displacement experiments, and viscosity measurements, indicating that the free ligand and its metal complexes can bind to DNA via an intercalation mode with the binding constants at the order of magnitude of 105–106 M –1, and the metal complexes can bind to DNA more strongly than the free ligand alone. In addition, antioxidant activities of the ligand and its metal complexes were investigated through scavenging effects for hydroxyl radical in vitro, indicating that the compounds show stronger antioxidant activities than some standard antioxidants, such as mannitol. The ligand and its metal complexes were subjected to cytotoxic tests, and experimental results indicated that the metal complexes show significant cytotoxic activity against lung cancer A 549 cells. 相似文献
959.
Yuan‐Yuan Gao Yue Ma Ya‐Li Wang Yu‐Zhang Tong Ming‐Fang Yang Qing‐Lun Wang Li‐Cun Li Dai‐Zheng Liao 《无机化学与普通化学杂志》2013,639(6):1015-1020
Two heterospin complexes [Cu(NIT3Py)(cda)H2O] · H2O ( 1 ) and [Cu(NIT2Py)(cda)H2O] · H2O · CH3OH ( 2 ) with CuII ions and pyridyl‐substituted nitronyl nitroxide radicals (NITxPy = 2‐(x′‐pyridyl)‐4,4,5,5‐tetramethyl‐imidazoline‐1‐oxyl‐3‐oxide, x = 3, 2; H2cda = 4‐hydroxy‐pyridine‐2,6‐dicarboxylic acid) were synthesized and characterized structurally and magnetically. The single crystal structures show that the two complexes are both two‐spin complexes, in which the different radicals make the two complexes have different hydrogen bonding interactions to form 2D and 1D supramolecular network for complexes 1 and 2 , respectively. The magnetic measurements indicate that complexes 1 and 2 both exhibit antiferromagnetic interactions between CuII and radicals. 相似文献
960.
Yao Huang Long‐Jiang Liu Ming‐Shan Zhou Xiao‐Jun Zhou Chao Zhu Fei‐E Fu Yong‐Ming Zhang 《无机化学与普通化学杂志》2013,639(10):1884-1887
Two metal‐organic frameworks, [Zn(dmtrz)(btrc)1/3]n ( 1 ) and [Zn2(dmtrz)2(btec)(H2O)2]n ( 2 ) (dmtrz = 3, 5‐dimethyl‐1‐H‐1, 2,4‐triazole, btrc = 1, 3,5‐benzenetricarboxylate, btec = 1, 2,4, 5‐benzenetetracarboxylate), were synthesized by hydrothermal reaction. The crystal structure analysis reveals that compound 1 is a dense 3D framework with Schläfli symbols of {43}2{46 · 66 · 83}3, which is a loh1 structure. Compound 2 is a 2D network. In addition, the photoluminescence of two compounds were studied in solid state at room temperature, together with their thermal analysis. 相似文献