TROVAFLOXACIN ORAL SUSPENSION

摘要

PROBLEM TO BE SOLVED: To obtain a trovafloxacin zwitterion crystal useful as an ingredient of a suspension for the therapy of microbism by employing a method where an aqueous solution of an acid-addition salt of trovafloxacin which shows a specific range of pH is subjected to precipitation procedure. SOLUTION: By precipitating zwitterions from an aqueous solution of an acid-addition salt of trovafloxacin (pH ca. 4 to ca. 10) and by retaining the solution for a defined time at room temperature, a hexahedral lath-shaped zwitterion crystal of trovafloxacin of the formula which has the following peaks in a wet cake X-ray diffraction pattern is obtained: [2θ( deg.) Cu, d(spacing)]=[6.2 (14.3)][8.6 (10.1)][11.8 (7.5)][12.4 (7.1)][12.8 (6.9)][16.1 (5.5)][16.8 (5.3)][18.6 (4.8)][19.5 (4.5)][20.1 (4.4)][22.6 (4.1)][23.7 (3.8)][26.7 (3.3)][28.3 (3.2)][29.9 (3.0)][37.7 (2.4)][39.0 (2.3)].