5566. Lonazolac

Nomenclature

CAS number: 53808-88-1
3-(4-Chlorophenyl)-1-phenyl-1H-pyrazole-4-acetic acid.
C17H13ClN2O2; mol wt 312.75.
C 65.29%, H 4.19%, Cl 11.34%, N 8.96%, O 10.23%.

Description and references

Prepn: R. A. Newberry, GB 1373212 (1974 to Wyeth), C.A. 82, 72987t (1975); G. Rainer, US 4146721 (1979 to Byk Gulden); G. Rainer et al., Arzneim.-Forsch. 31, 649 (1981). Pharmacology: R. Riedel, ibid. 655. Clinical studies: G. Lonauer et al., Z. Rheumatol. 40, 161 (1981); W. Siegmeth, P. Placheta, Wien. Klin. Wochenschr. 94, 145 (1982).

Chemical structure

Properties

Crystals from ethanol/water, mp 150-151°. uv max (methanol): 281 nm (ε 24800); (0.1N NaOH): 281 nm (ε 23700). pKa 4.3. LD50 in male mice, rats (mg/kg): 195, 165 i.v. (Riedel).

Derivative

Calcium salt.

Nomenclature

CAS number: 75821-71-5
Argun L (Merckle); Irritren (Byk Gulden).
C34H24CaCl2N4O4; mol wt 663.56.
C 61.54%, H 3.65%, Ca 6.04%, Cl 10.69%, N 8.44%, O 9.64%.

Properties

Solid, melts between 270-290° (dec). uv max (0.1N NaOH): 280 nm (ε 46400). LD50 in male, female mice, male, female rats (mg/kg): 670, 845, 730, 1000 orally (Riedel).

Therapeutic Category

Anti-inflammatory.

Keywords

Anti-inflammatory (Nonsteroidal); Arylacetic Acid Derivatives