T. Fujiwara
Mar 1, 1973
Citations
0
Influential Citations
15
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
Pyridoxal phosphate hydrate (PLPHYD) was crystallized from an aqueous solution in the form of monoclinic needles; space group P21⁄c with a=10.503, b=13.608, c=7.488 A, β=93.71° and four molecules in the unit cell. Prism-shaped crystal of pyridoxal phosphate methyl hemiacetal (PLPMHA) was obtained by dissolving the pyridoxal phosphate hydrate crystals into 90% methanol; space group P\barl, with cell dimensions, a=9.42, b=10.61, c=6.20 A, α=105.6°, β=95.7°, and γ=99.7°, and two molecules per cell. Intensity data were collected on an automated diffractometer for PLPHYD and photographically for PLPMHA. Crystal structures have been determined by the symbolic addition method. Refinements were done by the block-diagonal least-squares procedures, the final R value being 0.093 for PLPHYD and 0.112 for PLPMHA. The free aldehyde group of pyridoxal phosphate interacts with water molecule to form gem-diol in the crystalline state of PLPHYD and the gem-diol group of PLPHYD with methanol to form methyl hemiacetal. One o...