Linked Life Data

14552627

Source:http://linkedlifedata.com/resource/pubmed/id/14552627

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
2003-10-13
pubmed:abstractText
A series of 14-, 15-, and 16-membered nickel(II) cyclidene macrocycles appended with 2-aminoethyl(2-pyridine) receptors I-III, respectively, were prepared and characterized by X-ray crystallography and NMR techniques. The 14- and 15-membered macrocycles I and II exist in a planar or extended Z-configuration, whereas the 16-membered macrocycle III was saddle shaped and had two asymmetric configurations in the unit cell (IIIa in a "capped" configuration and IIIb in an "open" configuration). Variable-temperature (1)H NMR studies of III in CD(3)CN were conducted (25-65 degrees C), and at room temperature, the interconversion between capping and uncapping is slow on the NMR time scale, resulting in a broad spectrum, whereas at 65 degrees C, interconversion was fast. (1)H NMR binding studies indicated I-III bind unsaturated dicarboxylic acids in a 1:1 stoichiometry with binding constants approaching 400 M(-)(1) in CD(3)CN, and the binding strength was dependent on the shape of the macrocyclic cyclidene platforms, whereas monocarboxylic acids were not bound. Generally, the planar 14-membered cyclidene I bound diacids the weakest and the 16-membered cyclidene III bound diacids the strongest. The presence of nuclear Overhauser effect spectrometry cross peaks in a 20 mM solution of 1:1 II-maleic acid indicates that the binding mode is ditopic with the guest being encapsulated by the aminoethylpyridine arms above the macrocyclic framework.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0020-1669
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6749-63
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Nickel(II) cyclidenes with appended ethylpyridine receptor centers as molecular tweezers for dicarboxylic acids.
pubmed:affiliation
Department of Chemistry, Tufts University, Medford, Massachusetts 02155, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't