Preparation and some properties of glucosamine hydrochloride

Glucosamine hydrochloride was prepared by hydrolysis of chitin with concentrated hydrochloric acid and then chromatographed on 732 cation exchange column for purification. The purif ied glucosamine hydrochloride was identif ied by paper chromatography using the solvent system of pyridine, ethyl acetate, water and glacial acetic acid ( 5..5..3..1) and its Rf value was 0. 44. On redissolving in water, the value of the specif ic optical rotation of glucosame hydrochloride decreased with time f rom nearly 100.. to about 72.., and was stable after 2 hrs with .. 20 D = 71. 9... The chloride content of glucosamine hydrochloride product was 16. 74%. Its infrared spectrum shows that the characteristic absorption peaks occured at 3307. 8cm- 1、3098. 9cm- 1、1615. 0cm- 1、1534. 1cm- 1、1417. 9cm- 1、1093. 8cm- 1、1033. 6cm- 1、912. 0cm- 1 and 579. 1cm- 1.