Synthesis and pharmacological evaluation of oligoethylene ester derivatives as indomethacin oral prodrugs

Synthesis and antiinflammatory activity of novel indazolones

In this study, a series of new N2 substituted 1,2-dihydro-3H-indazol-3-ones (3a-d) as well as their condensed pyrazolo, pyridazino derivatives such as pyridazino[1,2-a]indazole-6,9,11-triones (4a-h) and 3,9-dioxo-3H,9H-pyrazolo[1,2-a]indazole (7) were synthesized. The antiinflammatory activity of some synthesized compounds was determined by carrageenan-induced rat paw edema technique using diclofenac as reference drug. The pharmacological data showed that most of the tested compounds exhibited a significant long lasting antiinflammatory activity, which in the case of compound 3b was superior to that of diclofenac.

Nitrosothiol esters of diclofenac: synthesis and pharmacological characterization as gastrointestinal-sparing prodrugs

Despite its widespread use, diclofenac has gastrointestinal liabilities common to nonsteroidal antiinflammatory drugs (NSAIDs) that might be reduced by concomitant administration of a gastrointestinal cytoprotectant such as nitric oxide (NO). A series of novel diclofenac esters containing a nitrosothiol (-S-NO) moiety as a NO donor functionality has been synthesized and evaluated in vivo for bioavailability, pharmacological activity, and gastric irritation. All S-NO-diclofenac derivatives acted as orally bioavailable prodrugs, producing significant levels of diclofenac in plasma within 15 min after oral administration to mice. At equimolar oral doses, S-NO-diclofenac derivatives (20a-21b) displayed rat antiinflammatory and analgesic activities comparable to those of diclofenac in the carrageenan-induced paw edema test and the mouse phenylbenzoquinone-induced writhing test, respectively. All tested S-NO-diclofenac derivatives (20a-21b) were gastric-sparing in that they elicited markedly fewer stomach lesions as compared to the stomach lesions caused by a high equimolar dose of diclofenac in the rat. Nitrosothiol esters of diclofenac comprise a novel class of NO-donating compounds having therapeutic potential as nonsteroidal antiinflammatory agents with an enhanced gastric safety profile.