Catalysis of Diribonucleoside Monophosphate Cleavage by Water Soluble Copper(II) Complexes of Calix[4]arene Based Nitrogen Ligands
作者:Roberta Cacciapaglia、Alessandro Casnati、Luigi Mandolini、David N. Reinhoudt、Riccardo Salvio、Andrea Sartori、Rocco Ungaro
DOI:10.1021/ja0632106
日期:2006.9.1
Calix[4]arenes functionalized at the 1,2-, 1,3-, and 1,2,3-positions of the upper rim with [12]ane-N-3 ligating units were synthesized, and their bi-and trimetallic zinc(II) and copper( II) complexes were investigated as catalysts in the cleavage of phosphodiesters as RNA models. The results of comparative kinetic studies using monometallic controls indicate that the subunits of all of the zinc(II) complexes and of the 1,3-distal bimetallic copper(II) complex 7-Cu-2 act as essentially independent monometallic catalysts. The lack of cooperation between metal ions in the above complexes is in marked contrast with the behavior of the 1,2-vicinal bimetallic copper(II) complex 6-Cu-2, which exhibits high catalytic efficiency and high levels of cooperation between metal ions in the cleavage of HPNP and of diribonucleoside monophosphates NpN'. A third ligated metal ion at the upper rim does not enhance the catalytic efficiency, which excludes the simultaneous cooperation in the catalysis of the three metal ions in 8-Cu-3. Rate accelerations relative to the background brought about by 6-Cu-2 and 8-Cu-3 (1.0 mM catalyst, water solution, pH 7.0, 50 degrees C) are on the order of 10(4)-fold, largely independent of the nucleobase structure, with the exception of the cleavage of diribonucleoside monophosphates in which the nucleobase N is uracil, namely UpU and UpG, for which rate enhancements rise to 10(5)-fold. The rationale for the observed selectivity is discussed in terms of deprotonation of the uracil moiety under the reaction conditions and complexation of the resulting anion with one of the copper(II) centers.
LIPOMACROCYCLES AND USES THEREOF
申请人:Cui Kunyuan
公开号:US20130156851A1
公开(公告)日:2013-06-20
What is described are macrocyclic compounds formed by reaction of a cyclic compound, which contains an amine, with an epoxide. The macrocyclic compound has the following structure:
When substituents R and R′ that are hydrophobic substituents, the macrocyclic compound functions as a lipid and is compatible with lipid systems, including liposomes and lipid particles. When present in certain lipid systems, the macrocyclic compound enhances the ability of the lipid system to facilitate delivery of therapeutic molecules to target cells in a mammalian subject.
US9233971B2
申请人:——
公开号:US9233971B2
公开(公告)日:2016-01-12
Synthesis and characterization of a new series of [12]aneN3 type macrocycles. Structures of two protonated metal-free ligands
作者:Patricia Hubsch-Weber、Marie-Thérèse Youinou
DOI:10.1016/s0040-4039(97)00241-4
日期:1997.3
The synthesis of a family of monotopic and ditopic ligands possessing a [12]aneN3 synthon and different spacers is described. The characterization of two of them by X-ray diffraction is also reported.