| 摘要 |
The new II type crystals of alpha -L-aspartyl-L-phenylalanine methyl ester consist of two kinds of crystals, IIA and IIB, which interconvert from one to the other depending upon the equilibrium content of the crystals, wherein one type of crystal, IIA, exhibits X-ray diffraction peaks at angles of diffraction of at least 20.6 DEG , 21.2 DEG , 5.0 DEG and 11.1 DEG , and the other type of crystal, IIB, exhibits X-ray diffraction peaks at angles of diffraction of at least 15.2 DEG , 11.1 DEG , 19.6 DEG and 4.5 DEG , as measured by X-ray diffractometry using CuK alpha radiation. The equilibrium moisture content of either of the kinds of crystals at a relative humidity of 78% is not higher than about 3%. …<??>The crystals of the present invention can be used advantageously in tablets or granules containing dipeptide sweeteners since they exhibit excellent storage stability. |
