The crystal and molecular structure of an intensely sweet chlorodeoxysucrose; 4,1 ',6 '-trichloro-4,1 ',6 '-tri-deoxy-galacto-sucrose

The crystal and the molecular structure of 4,1',6'-trichloro-4,1',6'-trideoxy-galacto-sucrose (TGS) was determined by X-ray analysis at 294 K. Crystals of TGS are orthorhombic,space group p2(1)2(1)2(1),with a = 7.318(3),b = 12.027(4),c = 18.136(5) angstrom,V = 1596(1) angstrom(3), Z = 4; D-x = 1.655 g(.)cm(-3), lambda(MoK alpha) = 0.71073 angstrom, mu(MoK alpha) = 5.44 cm(-1), F(000) = 816. The X-ray intensities of 2649 reflections with I >= 2.5 sigma(I) were measured with Zr-filtered MoK alpha-radiation. The structure was solved by the Patterson procedure and refined by full-matrix least-squares to a final R-value of 0.0298. Large conformational differences between TGS and sucrose were observed,particularly in the conformation of the glycosidic linkage. These differences originate from chlorine substitution,which affects intramolecular hydrogen bonding and sweet-taste glucophores.