Nomenclature
CAS number: 550-82-3
7-Hydroxy-3
H-phenoxazin-3-one 10-oxide; “diazoresorcinol”; resazoin.
C
12H
7NO
4; mol wt 229.19.
C 62.89%, H 3.08%, N 6.11%, O 27.92%.
Description and references
Prepn from resorcinol: Rast et al., DE 961829 (1957 to Bayer), C.A. 53, 15098 (1959).
Properties
Dark red, small crystals with greenish luster.
Insol in water, ether; sparingly sol in alcohol, glacial acetic acid;
sol in dil alkali hydroxides.Use
As indicator, using a soln of 0.1 g in 20 ml 0.1
N NaOH, and water to make 500 ml. pH: 3.8 orange, 6.5 dark
violet. In the detection of hyposulfite (sulfoxylate). In food research
(reductase test).