Light yellow to pale yellow solid. Uses: It is used as a pharmaceutical intermediate, mainly for the synthesis of fluoroquinolone drugs such as spafloxacin, piperate, norfloxacin, and other quinolone drugs, rifampicin, piazosin, etc., and veterinary drugs such as piperazine citrate, phosphate, and monohydrochlorate. It can also be used as a preservative, corrosion inhibitor, and various additives, etc.