Title:
METHOD FOR SEPARATING 6-(1-H-IMIDAZOL-1-YL)-7-NITRO-2,3(1H,4H)-QUINOXALINEDIONE
Document Type and Number:
Japanese Patent JPH083161
Kind Code:
A
Abstract:
PURPOSE: To separate 6-(1-H-imidazol-1-yl)-7-nitro-2,3-(1H,4H)-quinoxalinedione from its isomer mixture based on its nitro group in high purity.
CONSTITUTION: A mixture of 6-(1-H-imidazol-1-yl)-7-nitro-2,3-(1H,4H)- quinoxalinedione and 6-(1H-imidazol-1-yl)-8-nitro-2,3-(1H,4H)-quinoxalinedione in an aqueous solvent is adjusted to pH7.5-11 with an alkali substance and insoluble precipitate is separated and removed. The mother liquor is adjusted to pH of <7.5 and 6-(1H-imidazol-1-yl)-7-nltro-2,3-(1H,4H)-quinoxalinedione is separated as crystal from the other liquor.
Inventors:
HASEGAWA RYOICHI
TOMARU JUNICHIRO
TOMARU JUNICHIRO
Application Number:
JP16293694A
Publication Date:
January 09, 1996
Filing Date:
June 22, 1994
Export Citation:
Assignee:
NIPPON KAYAKU KK
International Classes:
C07D403/04; C07B63/00; (IPC1-7): C07D403/04; C07B63/00
Next Patent: IMIDAZOPYRIDINE DERIVATIVE AND ITS PRODUCTION