TY - JOUR
T1 - Pseudomerohedrally twinned monoclinic structure of unfolded free nona-ctin
T2 - Comparative analysis of its large conformational change upon encapsulation of alkali metal ions
AU - Guzei, Ilia A.
AU - Wang, Cheng
AU - Zhan, Yulian
AU - Dolomanov, Oleg V.
AU - Cheng, Yi Qiang
PY - 2009
Y1 - 2009
N2 - The title compound, C40H64O12, crystallizes in a pseudo-merohedrally twinned primitive monoclinic cell with similar contributions of the two twin components. There are two symmetry-independent half-mol-ecules of nona-ctin in the asymmetric unit. Each mol-ecule has a pseudo-S 4 symmetry and resides on a crystallographic twofold axis; the axes pass through the mol-ecular center of mass and are perpendicular to the plane of the macrocycle. The literature description of the room-temperature structure of nona-ctin as an order-disorder structure in an ortho-rhom-bic unit cell is corrected. We report a low-temperature high-precision ordered structure of free nona-ctin that allowed for the first time precise determination of its bond distances and angles. It possesses an unfolded and more planar geometry than its complexes with encapsulated Na +, K+, Cs+, Ca2+ or NH4 + cations that exhibit more isometric overall conformations.
AB - The title compound, C40H64O12, crystallizes in a pseudo-merohedrally twinned primitive monoclinic cell with similar contributions of the two twin components. There are two symmetry-independent half-mol-ecules of nona-ctin in the asymmetric unit. Each mol-ecule has a pseudo-S 4 symmetry and resides on a crystallographic twofold axis; the axes pass through the mol-ecular center of mass and are perpendicular to the plane of the macrocycle. The literature description of the room-temperature structure of nona-ctin as an order-disorder structure in an ortho-rhom-bic unit cell is corrected. We report a low-temperature high-precision ordered structure of free nona-ctin that allowed for the first time precise determination of its bond distances and angles. It possesses an unfolded and more planar geometry than its complexes with encapsulated Na +, K+, Cs+, Ca2+ or NH4 + cations that exhibit more isometric overall conformations.
UR - http://www.scopus.com/inward/record.url?scp=70349814425&partnerID=8YFLogxK
U2 - 10.1107/S0108270109033083
DO - 10.1107/S0108270109033083
M3 - Article
C2 - 19805886
AN - SCOPUS:70349814425
SN - 0108-2701
VL - 65
SP - o521-o524
JO - Acta Crystallographica Section C: Crystal Structure Communications
JF - Acta Crystallographica Section C: Crystal Structure Communications
IS - 10
ER -