Title: Etidronic Acid
CAS Registry Number: 2809-21-4
CAS Name: (1-Hydroxyethylidene)bisphosphonic acid
Synonyms: (1-hydroxyethylidene)diphosphonic acid; ethane-1-hydroxy-1,1-diphosphonic acid
Trademarks: Dequest 2010 (Solutia); Fostex P (Henkel)
Molecular Formula: C2H8O7P2
Molecular Weight: 206.03
Percent Composition: C 11.66%, H 3.91%, O 54.36%, P 30.07%
Literature References: Bisphosphonate antiresorptive agent. Prepn: H. von Baeyer, K. A. Hofmann,
Ber. 30, 1973 (1897); and characterization of the acid and disodium salt: F. Kasparek,
Monatsh. Chem. 99, 2016 (1968); B. Blaser
et al., Z. Anorg. Allg. Chem. 381, 247 (1971). Use as detergent builder: F. L. Diehl,
US 3159581 (1964 to Proctor & Gamble). Determn in pharmaceutical formulations: E. W. Tsai
et al., J. Pharm. Biomed. Anal. 11, 513 (1993). Symposium on clinical efficacy in malignancy-related hypercalcemia:
Am. J. Med. 82, Suppl 2A, 1-78 (1987). Review of pharmacology and therapeutic efficacy in resorptive bone disease: C. J. Dunn
et al., Drugs Aging 5, 446-474 (1994); of clinical safety and efficacy in osteoporosis: T. P. van Staa
et al., Pharmacotherapy 18, 1121-1128 (1998).
Properties: Crystallizes from water as the monohydrate. pK1 1.35 ±0.08; pK2 2.87 ±0.01; pK3 7.03 ±0.01; pK4 11.3. Very sol in water (69% at 20° C). Insol in acetic acid.
pKa: pK1 1.35 ±0.08; pK2 2.87 ±0.01; pK3 7.03 ±0.01; pK4 11.3
Derivative Type: Disodium salt
CAS Registry Number: 7414-83-7
Synonyms: Disodium dihydrogen (1-hydroxyethylidene)bis[phosphonate]; etidronate disodium
Trademarks: Didronel (Procter & Gamble); Diphos (Procter & Gamble); Etidron (Abiogen)
Molecular Formula: C2H6Na2O7P2
Molecular Weight: 249.99
Percent Composition: C 9.61%, H 2.42%, Na 18.39%, O 44.80%, P 24.78%
Properties: Crystallizes from water as the di- or tetrahydrate.
Use: Sequestering and chelating agent; scale and corrosion inhibitor.
Therap-Cat: Bone resorption inhibitor.
Keywords: Antiosteoporotic; Bone Resorption Inhibitor.
