Novel nonopioid non-antiinflammatory analgesics: 3-(aminoalkyl)- and 3-[(4-aryl-1-piperazinyl)alkyl]oxazolo[4,5-b]pyridin-2(3H)-ones

Abstract

A series of 3-(aminoalkyl)- and 3-[(4-aryl-1-piperazinyl)alkyl]oxazolo[4,5-b]pyridin-2(3H)-ones were prepared from their respective oxazolo[4,5-b]pyridin-2(3H)-ones. Several members of this group were found to possess potent analgesic activity in the mouse during a p-phenylquinone writhing induced test. Among them, phenylpiperazine compounds with two-carbon length alkyl chains, 2a and 2b, appeared by high analgesic with little toxicity having neither an antiinflammatory effect nor opioid receptor affinity. The synthesis and structure-affinity relationships for this series are detailed.

Synthesis, Analgesic and Antiinflammatory properties of Certain 5‐/6‐Acyl‐3‐(4‐substituted‐1‐piperazinylmethyl)‐2‐benzoxazolinones Derivatives

“…Some of them have turned out to be potent inhibitors of the iNOS [8]. The introduction of (4-aryl-piperazine-1-yl)alkyl moieties on various heterocyclic nuclei such as benzoxazolinones [5,9], oxazolopyridine [6,10], pyridazine [11,12], and pyrazolotriazine [13] led to favourable antinociceptive compounds.…”

Synthesis and Characterization of Some Transition Metal Complexes of 2-Amino-3-hydroxypyridine and its Application in Corrosion Inhibition

“…2). 2-Amino-3-hydroxypyridine is biologically important in the preparation of clinical antiin¯ammatory analgesics [3]. There are only few known transition metal complexes [4,5] or crystal structures [6] of 2-amino-3-hydroxypyridine: [Cp 2 Zr(ahp)] [4], [RuCl 2 (AsPh 3 ) 2 (ahp)] [5], and [(abhp) 2 Cu 2 Br 6 Á 2H 2 O] ( [6]; abhp 2-amino-4-bromo-3-hydroxypyridine).…”

Novel Antiinflammatory Analgesics: 3-(2-/4-Pyridylethyl)-Benzoxazolinone and Oxazolo[4,5-β]pyridin-2-one Derivatives

“…The resulting precipitate was collected by filtration, washed with water, and dried over P2O5 under vacuum to yield product as a white crystalline product. Mp: 212-214 °C [3] .…”

“…However, each class has its drawbacks: cyclooxygenase inhibitors induce gastrointestinal lesions while opiates induce tolerance, constipation, respiratory depression, physical dependency, and fear of addiction. The main objective in current pain research is to develop new, improved non-opioid analgesics which are as effective as the opioids but without their side effects [2,3] .…”