3.5- Pyrazolidinediones structure

Viewing aspirin as the progenitor drug, the first member of what we now caU the NSAIDs is phenylbutazone (Fig. 9.1f), a compound with a 1-aryl-3,5-pyrazolidinedione structure. Introduced by Geigy in Basel in 1946, phenylbutazone was extensively used for over 30 years for arthritis and other pain until replaced by newer NSAIDs and because of its adverse effects that included... 

This class of agents is characterized by the l-aryl-3,5-pyrazolidinedione structure. The presence of a proton, which is situated between the two electron-withdrawing carbonyl groups, renders these compounds acidic. The p Ta for phenylbutazone is 4.5. Oxyphenbutazone is a hydroxylated metabolite of phenylbutazone (Figure 13.12). 

Chemical Name 4-butyl-1 -(4-hydroxyphenyl)-2-phenyl-3,5-pyrazolidinedione Common Name p-hydroxyphenylbutazone Structural Formula oh... 

Chemical Name 4-butyl-1,2-diphenyl-3,5-pyrazolidinedione Common Name 3,5-dioxo-l, 2-diphenyl-4-n-butylpyrazolidine Structural Formula ... 

Therapeutic Function Antirheumatic, Analgesic, Antiinflammatory Chemical Name 3,5-Pyrazolidinedione, 4-butyl-l-phenyl-Common Name Mofebutazone Monophenylbutazone Mophebutazonum Structural Formula ... 

Levesque. L. etai (1991) The interaction of 3.5-pyrazolidinedione drugs with receptors for f-Met-Leu-Phe on human neutrophil leukocytes a study of the structure- activity relationship. Can. J. Physiol. Pharmacol., 69,419-425. Levesque. L. era (1992) Comparison of two classes of non-peptide drugs as antagonists of neutrophil receptors for f-Met-Leu-Phe. Pyrazolons and iodinated radiographic contrast agents. Biochem. Pharmacol., 43. 553-560. Derian. C.K. er at (1996) Selective inhibition of N-formylpeptide-induced neutrophil activation by carbamate-modified peptide analogues. Biochemistry, 35.1265-1269. 

The structure of 4-acyl-3,5-pyrazolidinediones has been studied by use of infrared absorption spectra.919 These studies indicate that one nuclear oxygen exists in its enolic form and the hydrogen is bonded to acyl oxygen in a chelate ring (XLVIII). These compounds are listed... 

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