作者:Ignacio Alfonso、Covadonga Astorga、Francisca Rebolledo、Vicente Gotor
DOI:10.1016/s0957-4166(99)00232-3
日期:1999.7
The syntheses of enantiopure tetraazamacrocycles analogous to cyclam, (S,S)-3, (R,R)-3 and (S,S,S,S)-4, have been carried out. NMR and semiempirical studies of 3 have revealed that this compound presents a rigid conformation with C-2 symmetry, which is stabilized by intramolecular bifurcated hydrogen bonds. Structural studies for macrocycle 4 have shown that the presence of two cyclohexane rings of (S,S) configuration leads to the loss of the D-2 symmetry in solution, which is in agreement with the AMI calculated structure. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.