Development new chiral derivatizing agent,AFGIT for amine drugs

• Main Authors: Huang, Shu-hwa, 黃淑華
• Other Authors: Chi-Ming Chen
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/58688638805112283768

碩士 === 台北醫學院 === 藥學研究所 === 85 === GITC(2,3,4,6-tetra-O-acetyl-b-D-glucopyranosyl isothiocyanate) is one GITCof the most widely applicable chiral derivatizing agent to resolve racemic amines . GITC containing isothiocyanate active moiety can react with those compounds contain amine functional group. Good resolution of the diastereomeric thiourea derivatives is generally achieved by HPLC via UV detection .Due to weak chromophore , GITC is not sensitive enough to be detected in low concentration . In order to improve the detection sensitivity, fluorescent chiral derivatizing agent，CGIT [6-O-(4'- methylcoumarin-7'- methoxycarbonyl)-2,3,4-tri-O- acetyl-a-D-glucopyranosyl isothiocyanate] was developed previously in our laboratory . Now we like to report here the synthesis of another new fluorescent chiral derivatizing agent，AFGIT [6- (9'-aminofluorenyl)-2,3,4-tri-O-acetyl-b-D-glucunopyranosyl isothiocyanate] . Glucuronolactone is served as a starting material for the preparation of AFGIT . Glucuronolactone was reacted with NaOH in 50% CH3OH aqueous to produce sodium glucuronate，and then was acetylated in the presence of p-toluenesulfonic acid . Incoporation of 9-aminofluorene to tetra-O-acetyl glucuronic acid as an amide linkage and following reaction with HBr affored the acetobromoglucuronic acid，subsequent reaction with AgSCN yielded the fluorescent chiral derivatizing agent，AFGIT . Derivatization was performed by reaction of AFGIT with primary or secondary amines in CH3CN for one hour . However amino acids were reacted in 50% aqueous CH3CN catalyzed by triethylamine for one hour . These diastereoisomeric thioureas was separated on a reversed HPLC column (C18) with a fluorescence detector (λex. : 270 nm ,λem. : 310 nm). Mobile phase of 55~70% CH3OH in 0.1% H3PO4 solution for racemic amino acids，60% CH3CN in 0.1% H3PO4 aqueous (v/v) for racemic adrenergic b-blockers，and CH3CN : CH3OH : 0.1% H3PO4 aqueous = 40 : 20 : 40 (v/v/v) for phenethylamines were applied . Twelve racemic amino acids (a =1.04~1.71) , four adrenergic b-blockers (a>1.1)，and four phenethylamines (a=1.05~1.15) were resolved successfully. Comparison of the detection sensitivity of DL-alanine derivatives of AFGIT and GITC, the detection sensitivity of AFGIT derivatives were at least 18 times more stronger then those of GITC derivatives . In conclusion，the new chiral derivatizing agent，AFGIT，is not only useful to resolve the racemic amine drugs or amino acids but also to enhance their detection sensitivity by the developed methods.