A novel 1:1 complex of potassium mikanin-3-O-sulfate with methanol.
Mikanin-3-O-sulfate (1), in the form of its potassium salt, together with mikanin (2) and alpinetin (3) were isolated from Mikania micrantha. The crystal structures of K(1) x CH3OH, 2 and 3 x H2O were established by X-ray crystallography. The potassium ions in K(1) x CHO3H are bridged by O5, O7 and O8 to form a chain of face-sharing KO8 coordination polyhedra, from which the aglycon units are outstretched to form a polymeric molecular column. Adjacent molecular columns are linked by pi-pi stacking between parallel, intercalating aglycon units to form layers matching the (101) family of planes, which are further interconnected into a three-dimensional supramolecular assembly. Sulfation at 3-OH induced better co-planarity and conjugation of the rings.
Jiang
R W
RW
Department of Chemistry, The Chinese University of Hong Kong, Hong Kong SAR, PR China.
He
Z D
ZD
But
P P
PP
Chan
Y M
YM
Ma
S C
SC
Mak
T C
TC
D019659:Asteraceae / Q000737:chemistry; D018360:Crystallography, X-Ray; D005419:Flavonoids / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D018515:Plant Leaves / Q000737:chemistry
D005419:Flavonoids; C446963:mikanin-3-O-sulfate; D000432:Methanol