Armstrong's acid

Armstrong's acid

IUPAC name Naphthalene-1,5-disulfonic acid
Other names Armstrong's acid
Identifiers
CAS number	81-04-9
PubChem	6666
ChemSpider	6414^Y
ChEBI	CHEBI:30890
Jmol-3D images	Image 1 Image 2
SMILES O=S(C2=CC=CC1=C(S(=O)(O)=O)C=CC=C12)(O)=O O=S(=O)(O)c1cccc2c1cccc2S(=O)(=O)O
InChI InChI=1S/C10H8O6S2/c11-17(12,13)9-5-1-3-7-8(9)4-2-6-10(7)18(14,15)16/h1-6H,(H,11,12,13)(H,14,15,16)^Y Key: XTEGVFVZDVNBPF-UHFFFAOYSA-N^Y InChI=1/C10H8O6S2/c11-17(12,13)9-5-1-3-7-8(9)4-2-6-10(7)18(14,15)16/h1-6H,(H,11,12,13)(H,14,15,16) Key: XTEGVFVZDVNBPF-UHFFFAOYAR
Properties
Molecular formula	C₁₀H₈S₂O₆
Molar mass	288.299 g/mol
Hazards
Main hazards	corrosive
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Armstrong's acid (naphthalene-1,5-disulfonic acid) is a strong acid which is related to toluenesulfonic acid and is used in chemical synthesis. It was named for British chemist Henry Edward Armstrong.^[1] It is sometimes used as a divalent counterion for forming salts of basic drug compounds, as an alternative to the related mesylate or tosylate salts. When used in this way such a salt is called a naphthalenedisulfonate salt, as seen with the most common salt form of the stimulant drug CFT.

References

^ Senning, Alexander (2007). Elsevier's dictionary of chemoetymology. Elsevier. pp. 30. ISBN 9780444522399. http://books.google.com/books?id=Fl4sdCYrq3cC&dq.