In June, 2002, Orange Health Company published a patent for a quick-release preparation containing mitiglinide calcium in China. In August, 2000 and June, 2006, Schwiya Company of France respectively disclosed the patents of synthetic methods for preparing mitiglinide calcium and its intermediate (indoline). Apart from the above patents, there are no other patent disclosures related to this compound. Therefore, the research and development, production and sales of mitiglinide calcium raw materials and its commonly used preparations (such as tablets and capsules) in China, as well as the application of this compound in patients with type 2 diabetes, will not infringe others' patents, but this compound cannot be synthesized by the method disclosed by Sylvia Company.