Several Important Physiological Activity Of Amino Acid Derivatives

This dissertation comprises two parts (1) studies on the synthesis of Serine(Bzl), Threonine (Bzl) , and Tyrosine (Bzl) (2) studies on the synthesis of histamine dihydrochloride.The first part: Serine (Bzl), Threonine (Bzl) , and Tyrosine (Bzl) are valuable protected amino acids in polypeptide synthesis, and useful pharmaceutical intermediates, from which many drugs have been prepared to cure such diseases as infertility, diabetes, arteriosclerosis, cardiovascular diseases and so on.We prepared the three compounds successfully by esterification, amino group protecting, etherification, base catalyzed hydrolysis, and acid catalyzed hydrolysis with yield of 46%, 46%, 27%, respectively. This procedure has been optimized and industrialized in our country for the first time.The second part: Histamine is a compound possessing significant biological activity and is one of the important mediators of many diseases, such as hypersensitivity, gastric ulcer, inflammation and so on. Moreover, histamine can be used to synthesize many medicines.In this dissertation, Histamine dihydrochloride has been conveniently synthesized by exploiting the decarboxylation of histidine using acetophenone as catalyst and octanol as solvent. The crude product was decolorized and recrystallized to give pure histamine, and the overall yield up to 40%. Up to now, this is the first time to replace cyclohexanol by octanol as the reacting solvent, and concentrated hydrochloric acid is used instead of dry HC1 gas, so this method is more economical and easier to operate. The process has been industrialized in our country.