Purpose To compare the effect and reliability of olsalazine sodium capsule in the treatment of ulcerative colitis (active phase) with those of salicylazosulphapyridine (SASP).

An Improved Synthetic Process of Osalazine;

Curative effect compared observation of Olsalazine and Sulfasalazine coloclysis on ulcerative colitis;

Therapeutic effect of Olsalazine on active ulcerative colitis;

To establish fluorescent method for the determination of oxaprozin enteric-coated capsules.

A capillary GC with headspace for determination of residual methanol, chloroform and pyridine inolsalazine sodium was established.