Nitrazine

Nitrazine

Names
IUPAC name (3E)-3-[(2,4-Dinitrophenyl)hydrazono]-4-oxonaphthalene-2,7-disulfonic acid
Other names Nitrazine yellow; Phenaphthazine
Identifiers
CAS Number	1716-22-9 Y
3D model (Jmol)	Interactive image
ChemSpider	5288340 Y
PubChem	6911856
InChI InChI=1S/C16H10N4O11S2/c21-16-11-3-2-10(32(26,27)28)5-8(11)6-14(33(29,30)31)15(16)18-17-12-4-1-9(19(22)23)7-13(12)20(24)25/h1-7,17H,(H,26,27,28)(H,29,30,31)/b18-15- Y Key: IHRSXGONVFFQQF-SDXDJHTJSA-N Y InChI=1/C16H10N4O11S2/c21-16-11-3-2-10(32(26,27)28)5-8(11)6-14(33(29,30)31)15(16)18-17-12-4-1-9(19(22)23)7-13(12)20(24)25/h1-7,17H,(H,26,27,28)(H,29,30,31)/b18-15- Key: IHRSXGONVFFQQF-SDXDJHTJBN
SMILES [O-][N+](=O)c1ccc(c([N+]([O-])=O)c1)N/N=C3/C(=C\c2c(ccc(c2)S(=O)(=O)O)C3=O)S(=O)(=O)O
Properties
Chemical formula	C16H10N4O11S2
Molar mass	498.40 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Nitrazine or phenaphthazine is a pH indicator dye often used in medicine. More sensitive than litmus, nitrazine indicates pH in the range of 4.5 to 7.5. Nitrazine is usually used as the disodium salt.

This test, however, can produce false positives. If blood gets in the sample or if there is an infection present, the pH of the vaginal fluid may be higher than normal. Semen also has a higher pH, so recent vaginal intercourse can produce a false reading.