Abstract:
:The use of four cyclodextrins (three native and one beta-CD derivative) as NMR chiral solvating agents to resolve the enantiomers of (+/-)-cizolirtine, 1, and its chemical precursor (the carbinol, (+/-)-2), was investigated. The best enantiodiscrimination occurred when beta-cyclodextrin was used. ROESY experiments were performed to qualitatively ascertain the most probable host-guest structures in D(2)O solution, and the binding features found were explained in terms of spatial fitting of the guest molecules into the macrocyclic cavities. No geometrical differences were noted between the two diastereomeric complexes formed by a cyclodextrin and a racemic substrate, so the magnetic nonequivalence induced on guest protons by the enantioselective binding had to be explained as a result of subtle disparities in the orientation and/or the conformational state of the complexed enantiomers.
journal_name
Chiralityjournal_title
Chiralityauthors
Redondo J,Blázquez MA,Torrens Adoi
10.1002/(SICI)1520-636X(1999)11:9<694::AID-CHIR5>3subject
Has Abstractpub_date
1999-01-01 00:00:00pages
694-700issue
9eissn
0899-0042issn
1520-636Xpii
10.1002/(SICI)1520-636X(1999)11:9<694::AID-CHIR5>3journal_volume
11pub_type
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