6403. 1-Naphthylamine-4-sulfonic Acid

Nomenclature

CAS number: 84-86-6
4-Amino-1-naphthalenesulfonic acid; naphthionic acid; Piria's acid.
C10H9NO3S; mol wt 223.25.
C 53.80%, H 4.06%, N 6.27%, O 21.50%, S 14.36%.

Description and references

Prepd on a large-scale by heating α-naphthylamine with equimolar amounts of concd H2SO4 at 180-200° or by heating α-naphthylamine acid sulfate: Fierz-David, Blangey, Fundamental Processes of Dye Chemistry (Interscience, New York, 1949).

Chemical structure

Derivative

Sesquihydrate.

Properties

Shiny needles from water. d425 1.673. Dec on heating without melting (the amide mp 206°). K at 25° = 2.1× 10-3. One gram dissolves in 3.45 l of water at 10°, in 3.22 l at 20°, in 1.69 l at 50°, in 438.5 ml at 100°. Very sparingly sol in alcohol, ether. Practically insol in acetic acid and acetic anhydride, but becomes sol when some pyridine is added. Sol in dil solns of alkali hydroxides or carbonates with a blue fluorescence.

Derivative

Sodium salt tetrahydrate.

Nomenclature

Naphthionine; 101-E.
C10H8NNaO3S.4H2O; mol wt 317.29.
C 37.85%, H 5.08%, N 4.41%, Na 7.25%, O 35.30%, S 10.11%.

Description and references

Ref: Piria, Ann. 78, 41 (1851).

Properties

Large monoclinic prisms from water, loses 3 1/2 mols water at 80°, anhydr at 130°. Sweet aftertaste. Freely sol in water with a blue fluorescence. Also sol in 95% alc. Practically insol in ether. Sparingly sol in concd aq and alcoholic caustic solns. pH of a 1% aq soln 6.8. Even ampuled aq solns discolor under the influence of light.

Derivative

Sodium salt glucoside.

Nomenclature

Naphthionine N-glucoside; 101-G.
C16H20NNaO8S; mol wt 409.39.
C 46.94%, H 4.92%, N 3.42%, Na 5.62%, O 31.26%, S 7.83%.

Description and references

Ref: Estève et al., Ann. Pharm. Fr. 10, 680 (1952).

Properties

White powder, bitter taste. Dec 255°. [α]D23.5 -113° (c = 10). Sol in water; slightly sol in alcohol. Practically insol in ether.

Use

The sodium salt is an important dye intermediate in the manuf of Congo Red, Fast Red A, Azo Rubine, and similar azo dyes.

Therapeutic Category

Sodium salt as hemostatic.

Keywords

Hemostatic