Synthesis, Anti-inflammatory and Analgesic Activity Evaluation of Some Mercapto Pyrimidine and Pyrimidobenzimidazole Derivatives

Abstract

4-Aminoantipyrine and 1,4-diaminobutane react with 4-isothiocyanato-4-methylpentan-2-one to give condensation products 1 and 2 respectively. Condensation of p-nitroaniline with 4-isothiocyanatobutan-2-one gave thiourea derivative 3 however coupling with 4-methyl-2-nitroaniline and 4-methoxy-2-nitroaniline gave cyclized products 5 and 6. 3,4-Diaminobenzophenone on condensation with 4-isothiocyanato-4-methylpentan-2-one in the presence of THF gave product 7 whereas the same reaction using methanol as solvent gave a mixture of hydroxy and methoxy compounds i.e. 8 which on treatment with acid under reflux temp. of MeOH gave pyrimidobenzimidazole derivative 9 in good yields. SMethyl pyrimidobenzimidazole derivative 10 was obtained by treating 9 with methanol under strongly acidic conditions. Pyrimidobenzimidazole 9 on reaction with methyl bromoacetate and ethyl bromoacetate gave compounds 11 and 12 respectively. Anti-inflammatory activity was carried out at 100 mg /kg p.o. of compounds 1-3 and 5-12. Compounds 5, 6, 8 and 10 showed 11,18,25 and 22% activity respectively whereas all other compounds were found to be inactive. Analgesic activity evaluation of 1, 2, 7-9 and 12 showed that compounds 2, 7 and 12 exhibited 50, 25 and 60% at 100 mg/kg p.o. and 50, 25 and 40% activity at 50 mg/kg p.o. respectively where as compounds 1, 8 and 9 were found to be inactive.

Heterocyclic inflammation inhibitors

“…A number of condensed pyrimidine derivatives viz bicyclic compound (45) [61], [66], (46) [62], [66], (47) [68], tricyclic compounds (48) [61], [64], [65], [67], [68], (49) [69], [70], (50) [69], tetracyclic compound (51) [66] and pentacycic derivative (Figure 52) [66] have been synthesized and screened for anti-in°ammatory activity. Many compounds at 100mg/kg p.o.…”

Transition Metal Complexes with Antipyrine‐Derived Schiff Bases: Synthesis and Antibacterial Activity

“…Thus, 4-amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one (4-aminoantipyrine) was discovered, a derivative with analgesic action, antipyretic, anti-inflammatory, antibacterian, and antineoplastic [31,32]. The derivatives of 4-aminoantipyrine are used in the synthesis of azo-colorant, in analytical chemistry for spectrophotometric determination of metal ions [33], in pharmacology, as an effective antitumor [34], analgesic [35], antiviral [36], anti-inflammatory [37], anticancer [38], and antimicrobial drugs [39][40][41][42].…”

Structural, optical and device characteristics of 1-(2-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-2-oxoethyl)pyridinium chloride

“…Particular attention has been directed to such class of materials due to their wide applications in biological systems [7]. In this context, broad spectra of bioactive antipyrine derivatives and their metal complexes have been investigated and diversities of bioactivities such as analgesic [8], anti-inflammatory [9], antimicrobial [10] and anticancer activity [11] have been reported. In addition, antipyrines have been used for fabricating modified Schottky junctions [12] and photodiodes [13].…”