Synthesis and the stereoselective enzymatic hydrolysis of flurbiprofen-basic amino acid ethyl esters.
Ethyl esters of flurbiprofen L-arginine (FP-Arg-OH), flurbiprofen L-lysine (FP-Lys-OH) and flurbiprofen p-guanidino-L-phenylalanine (FP-GPA-OH) were synthesized and then the release of flurbiprofen enantiomers from these derivatives in the presence of trypsin (Tp), carboxypeptidase B (CPB) and carboxypeptidase Y (CPY) were examined in order to evaluate their availability as prodrugs for flurbiprofen (FP). The ester bonds of the three racemic FP derivatives were hydrolyzed by Tp at about 3 to 20 times the rates of N-benzoyl-L-arginine ethyl ester (Bz-Arg-OEt), a specific substrate for Tp. (R)-FP was released faster than (S)-FP by either CPB or CPY from both FP-Arg-OH and FP-Lys-OH. On the other hand, FP-GPA-OH was not hydrolyzed at all by CPB and the hydrolysis rate of this compound by CPY was very slow. (S)-Flurbiprofen L-arginine ethyl ester ((S)-FP-Arg-OEt) was separated from (R)-FP-Arg-OEt by high-performance liquid chromatography. A comparison of the kinetic parameters for the tryptic hydrolysis of the two optically active FP-Arg-OEt diastereomers and those of Bz-Arg-OEt suggested that the orientation of the scissile bond in each diastereomer to the catalytic center of Tp is more favorable than that of Bz-Arg-OEt. However, no significant difference was found between the kinetic parameters for the two diastereomers, suggesting that the orientational difference between (S)-FP and (R)-FP in the diastereomers does not have any effect on the tryptic hydrolysis of the ester bond.(ABSTRACT TRUNCATED AT 250 WORDS)
Tsunematsu
H
H
Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Fukuoka University, Japan.
Yoshida
S
S
Horie
K
K
Yamamoto
M
M
D001120:Arginine / Q000737:chemistry* / Q000378:metabolism; D043424:Carboxypeptidase B; D002268:Carboxypeptidases / Q000737:chemistry; D043402:Cathepsin A; D002851:Chromatography, High Pressure Liquid; D004952:Esters / Q000138:chemical synthesis; D005480:Flurbiprofen / Q000737:chemistry* / Q000378:metabolism; D006868:Hydrolysis; D008239:Lysine / Q000737:chemistry* / Q000378:metabolism; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D011355:Prodrugs / Q000138:chemical synthesis*; D013237:Stereoisomerism; D014357:Trypsin / Q000737:chemistry
D004952:Esters; D011355:Prodrugs; C017351:4-guanidinophenylalanine; D010649:Phenylalanine; D005480:Flurbiprofen; D001120:Arginine; D002268:Carboxypeptidases; D043402:Cathepsin A; D043424:Carboxypeptidase B; D014357:Trypsin; D008239:Lysine