High-performance liquid chromatographic determination of N1-alkylnicotinamide in urine.
A simple high-performance liquid chromatographic method has been developed for determining N1-alkylnicotinamides, including C1-C5 alkyl derivatives, in urine. N1-Alkylnicotinamides were reacted with acetophenone in strong alkali medium at 0 degrees C and then formic acid was added. The reaction mixture was heated in acidic medium at above 93 degrees C, and the fluorescent product, 1-alkyl-7-phenyl-1,5-dihydro-5-oxo-1,6-naphthyridine, was chromatographed by HPLC, using a Zorbax SCX-300 column with a mixed mobile phase of acetonitrile-0.04 M ammonium phosphate, monobasic. N1-Alkylnicotinamides can be determined as 1,6-naphthyridine derivatives by a fluorometric detector at a level of 100 pg (signal/noise = 2). Recoveries of N1-alkylnicotinamides in urine were satisfactory. Interfering reaction products from NAD+ and NADP+ were clearly eliminated for determination of N1-alkylnicotinamides without pentyl derivatives.
Hirayama
T
T
Yoshida
K
K
Uda
K
K
Nohara
M
M
Fukui
S
S
D000328:Adult; D000478:Alkylation; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D008297:Male; D008745:Methylation; D008875:Middle Aged; D009243:NAD; D009249:NADP; D009287:Naphthyridines / Q000302:isolation & purification; D009536:Niacinamide / Q000031:analogs & derivatives* / Q000032:analysis / Q000138:chemical synthesis / Q000652:urine; D013050:Spectrometry, Fluorescence
D009287:Naphthyridines; D009243:NAD; D009536:Niacinamide; C013524:N-ethylnicotinamide; D009249:NADP