Absolute configuration of the alpha (1B)-adrenoceptor antagonist (+)-cyclazosin.
(+)-Cyclazosin is a quinazoline derivative pharmacologically characterized as alpha(1b)-adrenoceptor selective ligand in binding assays and alpha(1B)-selective antagonist in isolated tissues. In this work, we determined the absolute configuration of (+)-cyclazosin by X-ray crystallographic analysis applied to the (R,R)-(+)-tartrate of (-)-2, which is the enantiomer of the specific synthetic precursor of (+)-cyclazosin. Results indicated that (+)-cyclazosin has an R and S configuration at its C4a and C8a atoms, respectively.
Giardinà
Dario
D
Department of Chemical Sciences, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy. dario.giardina@unicam.it
Sagratini
Gianni
G
Grelli
Massimo
M
Gulini
Ugo
U
Melchiorre
Carlo
C
Antolini
Luciano
L
D058668:Adrenergic alpha-1 Receptor Antagonists; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008968:Molecular Conformation; D011799:Quinazolines / Q000737:chemistry*; D011810:Quinoxalines / Q000737:chemistry*; D013237:Stereoisomerism
D058668:Adrenergic alpha-1 Receptor Antagonists; D011799:Quinazolines; D011810:Quinoxalines; C080462:cyclazosin