Amide derivatives of [6-(5-methyl-3-phenylpyrazole-1-yl)-3(2H)-pyridazinone-2-yl]acetic acids as potential analgesic and anti-inflammatory compounds

In this study, amide derivatives of [6-(5-methyl-3-phenyl-pyrazole-1-yl)-3(2H)-pyridazinone-2-yl]acetic acid were synthesized and tested for their in vivo analgesic and anti-inflammatory activity by using the p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. The analgesic and anti-inflammatory activity of the compounds 6a, 6d, 6e, 6g, 6h and 6m were more potent than that of aspirin as an analgesic and indomethacin as an anti-inflammatory drug, respectively. The other derivatives generally resulted in comparable activity to reference compounds. Inhibitor activity of the active compounds on cyclooxygenase isoforms was also investigated by using in vitro human whole blood assay and found that these derivatives did not exert their analgesic and anti-inflammatory activities through COX inhibition and other mechanisms might be involved.     

Synthesis, Analgesic, and Anti-Inflammatory Activities of [6-(3,5-Dimethyl-4-Chloropyrazole-1-yl)-3(2H)-Pyridazinon-2-yl]Acetamides

A series of structurally diverse amide derivatives of [6-(3,5-dimethyl-4-chloro-pyrazole-1-yl)-3(2H)-pyridazinone-2-yl]acetic acid were prepared and tested for their in vivo analgesic and anti-inflammatory activity by using p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. The analgesic and anti-inflammatory activity of the compounds, 7c, 7d and 7k were found to be equipotent to aspirin (as an analgesic) and indometacin (as an anti-inflammatory drug), respectively. The other amide derivatives generally resulted in lower activity on comparision with reference compounds.     

Amide derivatives of [5-chloro-6-(2-chloro/fluorobenzoyl)-2-benzoxazolinone-3-yl]acetic acids as potential analgesic and anti-inflammatory compounds

In this study, we have explored the prevention of gastric side effects such as gastric lesions and bleeding while maintaining the high analgesic and anti-inflammatory activities by the derivatization of the carboxylate moiety into amides in [5-chloro-6-(2-chloro/fluorobenzoyl)-2-benzoxazolinone-3-yl]acetic acids. We have tested the analgesic and anti-inflammatory activities of the synthesized compounds in vivo by using p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. Compounds 3a, 3d, 3e, 3j and 3k potent analgesic and anti-inflammatory activities without gastric lesions in the tested animals. Therefore, conversion of the carboxylate moiety into certain amide derivatives generated potent analgesic and anti-inflammatory compounds while eliminating the gastrointestinal side effects. Cyclooxygenase (COX)-selectivity of the active compounds was also investigated by using in vitro human whole blood assay. Compounds 3a, 3e, 3h and 3k selective inhibition of COX-2 to some extent although the inhibitory activity was not very potent.     

Synthesis and analgesic and anti-inflammatory activity of ethyl (6-substituted-3 (2H)-pyridazinone-2-yl)acetate derivatives

A number of 6-substituted-3(2H)-pyridazinones and the corresponding methyl (6-substituted-3(2H)-pyridazinone-2-yl)acetate derivatives carrying the arylpiperazinyl structure present in potent antinociceptive agents reported in the literature were synthesized. As part of a programme a series of diverse arylpiperazine derivatives of ethyl (6-substituted-3(2H)-pyridazinone-2-yl)acetate were prepared and tested for their in vivo analgesic and anti-inflammatory activity by using p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. Side effects of the compounds were examined on gastric mucosa. None of the compounds showed gastric ulcerogenic effect compared with reference non-steroidal anti-inflammatory drugs (NSAIDs). On the basis of available data, the structure-activity relationship in the series of ethyl (6-substituted-3(2H)-pyridazinone-2-yl)acetate derivatives was also discussed. When compared to parent 6-substituted-3(2H)-pyridazinones, the new ester derivatives, for example ethyl (6-4-[(2-fluoro)phenyl]piperazine-3(2H)-pyridazinone-2-yl)acetate exhibited better analgesic and anti-inflammatory activity and a lower ulcerogenic effect.     

Synthesis and pharmacological evaluation of 1-(1-((substituted)methyl)-5-methyl-2-oxoindolin-3-ylidene)-4-(substituted pyridin-2-yl)thiosemicarbazide

Some novel Mannich base isatin derivatives were synthesized by reacting 1-(5-methyl-2-oxoindolin-3-ylidene)-4-(substitutedpyridin-2-yl)thiosemicarbazide with formaldehyde and several secondary amines. Their chemical structure was elucidated by means of spectral (FT-IR, (1)H- and (13)C-NMR and mass) analysis. Investigation of anti-inflammatory activity of synthesized compounds was done by carrageenan induced paw oedema method using diclofenac sodium as standard drug and analgesic activity was done by acetic acid induced writhing method. The synthesized compounds showed significant anti-inflammatory and analgesic activity.     

Synthesis and analgesic activity of some 4,6-disubstituted-3(2H)-pyridazinone derivatives

A series of 6-morpholino-4-aryl-3(2H)-pyridazinone alkanoic acids, their ester and amide derivatives were prepared and tested for their in vivo analgesic activity by using the p-benzoquinone-induced writhing test. The analgesic activity of the compounds 6-morpholino-4-aryl-3(2H)-pyridazinone (6a-b) were comparable but little lower than that of acetyl-salicylic acid (CAS 50-78-2) as an analgesic agent. The 6-morpholino-4-aryl-3(2H)-pyridazinones having a propanoic acid (10a-b), ester (7a) and amides (12a-b, 12d and 12g) as side chains at the position 2 of the pyridazinone ring showed higher activity than the reference compound without gastric ulceration forming potential. All other compounds generally showed higher activity but caused gastric ulceration in the animals.     

Synthesis and pharmacological evaluation of (indol-3-yl)alkylamides as potent analgesic agents.

A series of (indol-3-yl)alkylamides was synthesized and evaluated for analgesic activity. Two N-(pyridin-4-yl)acetamides, compounds 24 and 25, bearing benzyl or 4-fluorobenzyl moieties in 1-position of indole ring exhibited promising analgesic properties (ED50 = 8.1 and 11 mg/kg p.o., respectively), being as potent as the reference drugs flupirtine (CAS 56995-20-1), ibuprofen (CAS 15687-27-1) and diclofenac (CAS 15307-86-5). The two test compounds were tested for their anti-inflammatory activity by carrageenin-induced edema in rat paw test. 4-Fluorobenzyl derivative 25 whose ID50 was 0.085 +/- 0.021 mmol/kg was selected as a lead compound for further pharmacomodulation.     

Synthesis and evaluation of the analgesic and anti-inflammatory activity of new 3(2H)-pyridazinone derivatives

A series of 6-substituted-3(2H)-pyridazinone derivatives were synthesized and evaluated for analgesic and anti-inflammatory activities. The structures of these new pyridazinone derivatives were confirmed by their IR, 1H-NMR spectra and elementary analysis. Analgesic and anti-inflammatory activities of the title compounds have been evaluated. Four of the ten tested compounds possessed significant analgesic effects in the phenylbenzoquinone-induced writhing test (PBQ test). The most active derivatives 8a, 8b, 8d, 8e were void of gastric ulcerogenic effect or acute toxicity at the maximal dose (200 mg/kg p.o.). In the carrageenan-induced paw edema model, compound 8d (6- [4- (2-fluorophenyl) piperazin-1-yl]-3(2H)-pyridazinone) showed anti-inflammatory activity similar to that of the standard drug indometacin (CAS 53-86-1). A significant dependence of the anti-inflammatory effect on the substituents was observed; The pharmacological study of these compounds confirms that modification of the chemical group at position 6 of the 3(2H)-pyridazinone ring influences analgesic and anti-inflammatory activities.     

Synthesis and anti-inflammatory activity of derivatives of 5-[(2-disubstitutedamino-6-methyl-pyrimidin-4-yl)-sulfanylmethyl]-3H-1,3,4-oxadiazole-2-thiones

Synthesis and results of anti-inflammatory activity in vivo of 5-[(2-disubstitutedamino-6-methyl-pyrimidin-4-yl)-sulfanylmethyl]-3H-1,3,4-oxadiazole-2-thiones and their S-alkyl-, N(3)-acyl- and N(3)-aminomethyl derivatives are described. All the tested compounds possess anti-inflammatory activity comparable to that of acetylsalicylic acid and some derivatives of 5-[(6-methyl-2-piperidin-1-yl-pyrimidin-4-yl)-sulfanylmethyl]-3H-1,3,4-oxadiazole-2-thione were found to be much more active than ibuprofen.     

Synthesis of 2-(aryl)-5-(arylidene)-4-thiazolidinone derivatives with potential analgesic and anti-inflammatory activity

A series of novel N-[5-(arylidene)-2-(aryl)-4-oxo-thiazolidin-3-yl]-4-biphenylcarboxamide derivatives was synthesized and evaluated for analgesic and anti-inflammatory activity. In this study, biphenyl-4-carboxylic acid hydrazide was converted to the corresponding aryl hydrazones using aryl aldehydes in the presence of catalytic amount of glacial acetic acid. The aryl hydrazones on reaction with thioglycolic acid in the presence of anhydrous zinc chloride yielded N-[2-(aryl)-4-oxo-thiazolidin-3-yl]-4-biphenylcarboxamide which further on reaction with aromatic aldehydes in the presence of anhydrous sodium acetate and glacial acetic acid furnished the title compounds. All compound exhibited anti-inflammatory activity at the dose 10?mg/kg. The structures of all these newly synthesized compounds were confirmed by their elemental analyses (C, H, N) and spectral data (IR and ¹H NMR).     

Synthesis and analgesic and anti-inflammatory activity of some new (6-acyl-2-benzoxazolinone and 6-acyl-2-benzothiazolinone derivatives with acetic acid and propanoic acid residues

In this study for developing potent analgesic and anti-inflammatory compounds, we synthesized 6-acyl-2-benzoxazolinone and 6-acyl-2-benzothiazolinone derivatives with acetic acid and propanoic acid side chain, and performed preliminary screening of their in vivo analgesic and anti-inflammatory activities at a single dose of 100 mg/kg inmice by a p-benzoquinone-induced writhing test and a Carrageenaninduced hind paw edema model, respectively. We also determined their gastric ulceration effects in the tested animals. Propanoic acid derivatives were generally found to have higher analgesic and anti-inflammatory activities, and among them, 3-(6-benzoyl-2-benzothiazolinon-3-yl)propanoic acid (Compound 4 a) exhibited the highest analgesic and anti-inflammatory activity. However, all compounds showed lower anti-inflammatory effects than we observed for indomethacin at 10 mg/kg dose. Consequently, 6-acyl-2-benzoxazolinone/2-benzothiazolinones having propanoic acid side chain might lead to further studies for developing better candidates with potent analgesic and anti-inflammatory effects while acetic acid derivatives do not exhibit comparable satisfactory features.     

Amide derivatives of [6-acyl-2-benzothiazolinon-3-yl] acetic acids as potential analgesic and anti-inflammatory compounds

In this study, we investigated the analgesic and anti-inflammatory activities of [6-acyl-2-benzothiazolinon-3-yl]acetic acids by the derivatization of the carboxylate moiety into amides. We have tested the analgesic and anti-inflammatory activities of the synthesized compounds in vivo by using p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. Compounds 4h, 4i, 4n, and 4o showed comparable analgesic and anti-inflammatory activities to the references without gastric lesions in the tested animals. In addition, all compounds also tested for their inhibitory activity against cyclooxygenase (COX)-1, COX-2 and 5-lipoxygenase (LOX), but no significant inhibition was observed under assayed conditions.     

Synthesis and hypolipidemic activity of novel 2-(4-(2-amino-6-(4-substituted phenyl) pyrimidin-4-yl)-2-substituted phenoxy) acetic acid derivatives

A novel series of 2-(4-(2-amino-6-(4-substituted phenyl) pyrimidin-4-yl)-2-substituted phenoxy) acetic acid derivatives were efficiently synthesized. The synthesized compounds were evaluated for their in vivo hypolipidemic activity, using high-fat-diet-induced hyperlipidemia in rats. Some of these compounds showed significant antihyperlipidemic activity.     

4-(5-chloro-2(3H)-benzoxazolon-3-yl) butanoic acid derivatives: synthesis, antinociceptive and anti-inflammatory properties

In this study, 4-(5-chloro-2(3H)-benzoxazolone-3-yl)butanoic acid and its ethyl ester as well as its ten new amide derivatives have been synthesized. Their structures have been elucidated by IR, (1)H-NMR spectra and elemental analysis. The compounds were screened for antinociceptive and anti-inflammatory activities. The highest antinociceptive and anti-inflammatory activities were exhibited by Compound 11 which has carboxylic acid structure. A various decrease in antinociceptive and anti-inflammatory activity was observed by amidation of the carboxylic acid moiety of this compound.     

Anti-inflammatory and analgesic activities of newly synthesized chiral peptide derivatives using (3-benzoyl- 4,5-dioxo-2-phenyl-pyrrolidin-1-yl)acetic acid ethyl ester as starting material

A series of heterocyclic derivatives was synthesized using (3-benzoyl-4,5-dioxo-2-phenyl-pyrrolidin-1-yl)acetic acid ethyl ester 1 as starting material. Treatment of 1 with 1 N NaOH or hydrazine hydrate afford the corresponding acid 2 and acid hydrazides 4 and 5, which were reacted with several reagents to produce some new peptido hetero-organic derivatives 6-12. The pharmacological screening showed that many of these newly synthesized compounds have good anti-inflammatory and analgesic activities comparable to diclofenac potassium and valdecoxib as reference drugs.     

Synthesis and evaluation of analgesic,anti-inflammatory and antimicrobial activities of 6-acyl-3-piperazinomethyl-2-benzoxazolinones

In this study, 16 new 6-difluorobenzoyl-3-piperazinomethyl-2-benzoxazolinones were synthesized by Mannich reaction. Their chemical structures were proven by IR, 1H-NMR and elemental analysis. The compounds were screened for their analgesic and anti-inflammatory activities. A modified Koster test, using acetylsalicylic acid (ASA, CAS 50-78-2) as the reference drug, was used to assess analgesic activity. The anti-inflammatory activity was evaluated by the carrageenan induced hind-paw oedema test. The analgesic activities of all compounds were higher than their anti-inflammatory activities and therefore the prominent analgesic actions of the compounds are thought to be due to a central effect. The microbiological effects of the compounds were evaluated in vitro against various pathogenic fungi and bacteria using the microdilution method. Most of the compounds were found to be inactive against bacteria and fungi. One of the compounds (31) possessed considerable analgesic activity as well as moderate antibacterial activity against S. aureus. Another compound (3m) showed analgesic and antifungal activities comparable to those of ASA and fluconazole (CAS 86386-73-4), respectively.     

Synthesis and spectral characterization of new bis(2-(pyrimidin-2-yl)ethoxy)alkanes and their pharmacological activity

The pyrimidine nucleus is an important component of nucleic acids (DNA and RNA) and vitamins (B(2) and folic acid). It is evident from the literature that pyrimidine derivatives possess a wide spectrum of biological activities such as antioxidant, anticancer, antibacterial, and anti-inflammatory activities. On the basis of diverse biological activities, we attempted to synthesize a series of novel bis(2-(pyrimidin-2-yl)ethoxy)alkanes 5a-j in four steps with good yields. 2-Chloropyrimidine (1) was reacted with diethyl malonate in the presence of sodium hydride in dry dimethyl formamide to yield the intermediate diethyl 2-(pyrimidin-2-yl)malonate (2), which on further reaction with sodium chloride and dimethyl sulfoxide yielded ethyl 2-(pyrimidin-2-yl)ethanoate (3). Reduction with sodium borohydride (NaBH(4) ) resulted in the formation of 2-(pyrimidin-2-yl)ethanol (4). This was further reacted with various dibromoalkanes to obtain the title compounds 5a-j. In this current study, we evaluated the antioxidant properties of the title compounds using four in vitro test systems: the 2,2-diphenyl-2-picrylhydrazyl radical-, superoxide radical-, and hydroxyl radical-scavenging assays, and the anti-lipid peroxidation activity test. The title compounds showed promising antioxidant activity when compared to butylated hydroxytoluene. The potency of their antioxidant activity was mainly influenced by the alkyl fragment attached to 2-(pyrimidin-2-yl)ethanol. The ethyl and butyl fragments linked to oxygen led to increased antioxidant activity of the title compounds (i.e., 5b and 5d) in all our in vitro assays.     

4-(1,2-Benzisothiazol-3-yl)alkanoic and phenylalkanoic acids: synthesis and anti-inflammatory, analgesic and antipyretic activities.

Continuing their studies on benzisothiazolyl derivatives, Authors refer to the preparation and pharmacological properties of 4-(1,2-benzisothiazol-3-yl) alkanoic and phenylalkanoic acids. All substances were tested for anti-inflammatory, analgesic and antipyretic properties. As reference compounds, 1,2-benzisothiazolin-3-one and 4-(3-oxo-1,2-benzisothiazolin-3-yl) phenylacetic acid, as prototypes of benzisothiazolinonic derivation. Ibuprofen, as a prototype of substituted arylalkanoic acids, and Phenylbutazone were used. Analysis of the data leaded to the following conclusions. Introduction of the aryl moiety, passing from benzisothiazolylalkanoic to benzisothiazolyl-phenylalkanoic structures, produced a remarkable increase of activity. 2-[4-(1,2-benzisothiazol-3-yl)phenyl] propionic and 2-[4-(1,2-benzisothiazol-3-yl)phenyl]butyiric acids showed anti-inflammatory, analgesic and antipyretic properties comparable to those of Ibuprofen. Substantial differences in variations in activities were observed comparing the properties of benzisothiazolylphenylalcanoic acids with those of the benzisothiazolinonic series, object of preceding studies.     

Pharmacological profile of 4-(2',4'-difluorobiphenyl-4-yl)-2-methylbutyric acid (deoxoflobufen)

4-(2',4'- Difluorobiphenyl-4-yl)-2-methylbutyric acid (deoxoflobufen, VUFB 19053, CAS 847475-35-8) has been developed as a new omega-biphenyl-alkanoic acid and studied in comparison with the racemic form of 4-(2',4'-difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic acid (flobufen, CAS 112344-52-2). The compounds were tested in a series of models including acute inflammation induced by carrageenan, adjuvant arthritis, in vitro inhibition of the leuktotriene B4 (LTB4) production, reaction of the graft versus the host (GVHR), production of specific antibodies against ovalbumin, peritoneal exudate formation induced by thioglycollate and phagocytosis of thioglycollate-stimulated mouse peritoneal macrophages. Deoxoflobufen exhibited strong anti-inflammatory, antiarthritic and immunomodulatory effects in most of the performed tests. Anti-inflammatory and antiarthritic effects are fully comparable with those of flobufen, however, the compound is less toxic and has apparently stronger immunomodulating effects.     

Synthesis and pharmacological evaluation of some 3-(2-methylphenyl)-2-substituted amino-quinazolin-4(3H)-ones as analgesic and antiinflammatory agents

A variety of novel 3-(2-methylphenyl)-2-substituted amino-quinazolin-4(3H)-ones were synthesized by reacting the amino group of 2-hydrazino-3-(2-methylphenyl)-quinazolin-4(3H)-one with a variety of aldehydes and ketones. The starting material 2-hydrazino-3-(2-methylphenyl)-quinazolin-4(3H)-one was synthesized from 2-methyl aniline. The title compounds were investigated for analgesic, anti-inflammatory and ulcerogenic index activities. Among these, the compound 2-(1-ethylpropylidene)-hydrazino-3-(2-methylphenyl)-quinazolin-4(3H)-one emerged as the most active compound for analgesic activity, while the compound 2-(1-methylbutylidene)-hydrazino-3-(2-methylphenyl)-quinazolin-4(3H)-one showed most potent anti-inflamma-tory activity of the series and was moderately more potent in its anti-inflammatory activity when compared to the reference standard diclofenac sodium (CAS 15307-86-5). Interestingly, the test compounds showed only mild ulcerogenic potential when compared to acetylsalicylic acid (CAS No: 50-78-2).