T. Taga, Taneno Kaji, K. Osaki
1985
Citations
0
Influential Citations
7
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
The crystal structure of the calcium salt of D-glycero-D-gulo-heptonic acid has been determined by the X-ray method. The crystal is monoclinic of space group P21 with unit-cell dimensions of a=10.064(1), b=10.540(2), c=11.340(2) A, and β=108.92(1)°. The intensity data for 1754 unique reflections were measured with an automatic diffractometer. A trial structure, obtained by the direct method, was refined by the full-matrix least-squares method to R=0.030. The two independent heptonate anions have different conformations, and they chelate a calcium ion in different ways. The calcium ion is surrounded by eight oxygen atoms in a deformed dodecahedral form, the Ca···O distances ranging from 2.40 A to 2.48 A. The distortion of the moleular strcuture of the heptonate anions due to the calcium chelation was discussed in relation to the calcium-binding sites on a linear carbohydrate chain.