A new anti-inflammatory derivative of imidazole which is less ulcerogenic than indomethacin in rats

Design and Synthesis of Novel Pyrazole-Substituted Different Nitrogenous Heterocyclic Ring Systems as Potential Anti-Inflammatory Agents

With the aim of developing novel anti-inflammatory scaffolds, a new series of pyrazole-substituted various nitrogenous heterocyclic ring systems at C-4 position were synthesized through different chemical reactions and validated by means of spectral and elemental data. The new obtained compounds were investigated for their anti-inflammatory activity using the carrageenan-induced paw edema standard technique and revealed that, compound 6b showed increased potency with % inhibition of edema 85.23 ± 1.92 and 85.78 ± 0.99, respectively, higher than the standard reference drugs indomethacin and celebrex (72.99% and 83.76%). Molecular modeling studies were initiated herein to validate the attained pharmacological data and provide understandable evidence for the observed anti-inflammatory behavior.

Synthesis, and Pharmacological Screening of Novel Sulfamoylphenylcarbamoylquinoxaline Derivatives as Anti-Inflammatory, Analgesic and Antitumour Agents

Treatment of quinoxaline-2,3-dicarboxylic acid anhydride with some sulfonamides gave 3-sulfamoylphenylcarbamoylquinoxaline-2-carboxylic acid derivatives. While fusing the anhydride with the same sulfonamides produced the corresponding 3-sulfamoylphenylcarbamoylquinoxalines. On refluxing 3-sulfamoylphenylcarbamoyl derivatives with acetic anhydride gave the pyrrolo[3,4- d]quinoxaline derivatives. The imide linkage in the latter compound was opened via its reaction with amines under fusion conditions and quinoxalin-2,3-diamides were obtained. The pharmacological evaluation for some of the synthesised compounds revealed that in anti-inflammatory activity in chronic models, 3-{[4-(N-pyrimidin-2-ylsulfamoyl)phenyl]carbamoyl}quinoxaline-2-carboxylic acid was equipotent to the reference drug, indomethacin as well as having nonulcerogenic effect. All tested compounds showed moderate analgesic activity compared to the reference drug. The antitumour activity for the tested compounds showed that 3-{[4-(N-(5-methylisoxazol-3-yl)sulfamoyl)phenyl]carbamoyl}quinoxaline-2-carboxylic acid, 4-(1,3-dioxo-1H-pyrrolo[3,4-b]quinoxalin-2(3H)-yl)-N-(pyrimidin-2-yl)-benzenesulfonamide and N-carbamimidoyl-4-(1,3-dioxo-1H-pyrrolo[3,4-b]quinoxalin-2(3H)-yl)benzenesulfonamide were the most effective against the liver carcinoma cell line showing IC50 values 0.5, 0.79 and 1.84 IC50 μg mL−1, respectively.

Isopropyl 2-[2-(2,6-dichloro-anilino)phen-yl]acetate

In the title compound, C(17)H(17)Cl(2)NO(2), the NH group exhibits an intra-molecular hydrogen bond to the carbonyl O atom and no inter-molecular hydrogen bonding, in contrast with previous studies. The dihedral angle between the two benzene rings is 58.57 (5)°. The ester group is planar, the greatest deviation from planarity being 0.0135 (11) Å for the ether O atom.

Antiinflammatory and ulcerogenic activities of Salvia triloba extracts

In continuation of our research on Salvia triloba, acute and chronic antiinflammatory and ulcerogenic activities of chloroform, ethanol, butanol and water extracts were detected at 25 mg/kg p.o. The chloroform extract showed the highest antiinflammatory activity in both acute and chronic models, while the ulcerogenic effects of all tested extracts were found to be less than that of acetyl salicylic acid.

Synthesis and evaluation of the analgesic and antiinflammatory activities of O-substituted salicylamides

The present investigation deals with the synthesis of some new salicylamidoacetyl sulfonamides 3a,b, salicylamido ethylacetate 4, salicylamido acetic acid hydrazide 5, which is considered as the key intermediate for the synthesis of several series of new compounds such as salicylamido pyrazol 6 and pyrazolone 7. N-imido-derivatives 9, 10, 11, thiadiazole 13, oxadiazole 14, 15, Schiffs bases 16a-f. Cyclocondensation of Schiffs bases with thioglycolic acid gave thiazolidinone 18a-c while with acetylchloride afforded azitidinones 19a-c and with acetic anhydride gave 1,4-benzoxazepine-3,5-dione. Some of the compounds were tested for their analgesic and antiinflammatory activities as well as ulcerogenic effects. Some derivatives were more effective than salicylamide and ulcerogenic activity was variably lowered.

Synthesis of new salicylamide derivatives with evaluation of their antiinflammatory, analgesic and antipyretic activities

A new series of pyridazine, pyrazoles, pyrazolidine-3,5-dione, Semicarbazide, thiosemicarbazides, hydantoin, thiohydantoins, 1,2,4-triazoles, S-triazolo[3,4-b]-1,3,4-thiadiazoles incorporated indirectly into salicylamide moiety at position 2 were synthesized. Also the synthesis of novel series of 3-salicylamido-2-hydroxypropyl-amine derivatives were prepared. Several of these compounds were screened for antiinflammatory, analgesic, antipyretic and ulcerogenic activities.

Synthesis and anti-phlogistic potency of some new non-proteinogenic amino acid conjugates of "Diclofenac"

In search for more potent, particularly less ulcerogenic gastritis that hopefully replace the universal NSAID "Diclofenac", (2-[(2,6-dichlorophenyl)amino]-phenylacetic acid, C.A.S. 15307-86-5), twelve new non-proteinogenic amino acid conjugates of the drug, namely that of sarcosine, beta-alanine, D-leucine and D-phenylalanine, were synthesized and biologically screened for their anti-inflammatory, analgesic and ulcerogenic activity in rats. "Diclofenac" amino acid esters (IIa-d), were synthesized via the corresponding HOSu or HOBt active esters. Alkaline hydrolysis (NaOH) followed by acidification (KHSO4) or thioamide formation (Lawsson's Reagent, C.A.S. 19172-47-5), afforded the corresponding free acids IIIa-d or the thioamides IVa-d respectively. Interestingly, in contrary to the parent "Diclofenac", the synthesized candidates (except IIId), were entirely nonulcerogenic in rats. Further, they considerably retained a generalized anti-phlogistic activity. The major "Diclofenac" irritating gastric side effect was thus eliminated. Particularly, the sarcosine conjugate IIa and its thiomimic IVa exhibit promising therapeutic perspectives.

Antithrombotic and ulcerogenic effects of fenflumizole, a new anti-inflammatory imidazole derivative, in rats

Fenflumizole (2-(2,4-difluorophenyl)-4,5-bis(4-methoxyphenyl) imidazole) was given to rats in a single oral dose of 30 mg/kg. The plasma concentration of fenflumizole reached a peak 2-3 hr after the dosing in non-fasted as well as fasted rats. Two metabolites (demethylation products) of fenflumizole were also detected in the plasma, but only in traces. Fenflumizole (30 and 100 mg/kg) and aspirin (100 mg/kg), given orally 2 hr prior to i.v. arachidonate (80 mg/kg), were effective in protecting the rats from death. Fenflumizole in single oral doses of 100 to 800 mg/kg dose-dependently developed erosions in the rat gastric mucosa, but was much less ulcerogenic than aspirin (3.12-200 mg/kg). Thus, fenflumizole seems to possess a potent antithrombotic activity and a relatively low gastro-ulcerogenicity in rats.

Fenflumizole: interactions with the arachidonic acid cascade

Fenflumizole (2-(2,4-difluorophenyl)-4,5-bis(4-methoxyphenyl)imidazole), a new non-steroidal anti-inflammatory agent, was investigated for interference with cyclo-oxygenase activity in vivo, ex vivo and in vitro in comparison with indomethacin (and aspirin). Fenflumizole was comparable to indomethacin ex vivo in inhibition of thromboxane (TX)A2 production in rabbit platelets and inhibition of prostaglandin (PG)I2 (approximately prostacyclin) generation in rabbit mesenteric arteries and in vivo as an inhibitor of PGE2 formation in inflammatory exudates in rats. Fenflumizole was 18 times less active than indomethacin in inhibition of PGE2 synthesis in vitro and 170 times weaker as an inhibitor of PGI2 generation in the rat stomach mucosa ex vivo. Fenflumizole was 20-50 times more potent than indomethacin in vivo in inhibition of arachidonic acid induced bronchoconstriction in guinea-pigs, in inhibition of platelet aggregation on tendons superfused with blood from rabbits and in vitro in inhibition of aggregation of human and rabbit platelets. Neither fenflumizole nor indomethacin inhibited TXA2-synthetase in vitro. Aspirin-when tested-was less potent than fenflumizole and indomethacin. It is concluded that fenflumizole is a potent cyclo-oxygenase inhibitor. The very potent activity of fenflumizole against platelet aggregation and bronchoconstriction suggests a selectivity in the mode of action. The weak inhibition of gastric PGI2 generation may account for the previously observed weak gastro-ulcerogenicity of fenflumizole.

Pharmacodynamics and toxicology of fenflumizole, a new non-steroidal anti-inflammatory imidazole derivative

Fenflumizole, (2-(2,4-difluorophenyl)-4,5-bis(4-methoxyphenyl) imidazole), a new non-steroidal anti-inflammatory agent, was investigated for anti-inflammatory, analgesic and anti-pyretic activity in experimental animals. Comparison was made to other non-steroidal anti-phlogistics. Furthermore, general pharmacodynamics and toxicity of fenflumizole was studied. Fenflumizole was comparable to or weaker than indomethacin in models of acute inflammation (carrageenin paw oedema and pleurisy, rats, ultraviolet erythema, guinea-pigs) and stronger than indomethacin as an analgesic (writhing, mice). As an antipyretic agent (arachidonic acid pyresis, rats) fenflumizole was 3 times weaker than indomethacin. The acute gastro-ulcerogenicity and toxicity of fenflumizole was low as compared to reference drugs. No untoward activity of fenflumizole on respiratory and circulatory systems was observed in rabbits and dogs. Fenflumizole is a potential new therapeutic agent with anti-inflammatory, analgesic and anti-pyretic activities comparable to other anti-phlogistics but with reduced side effects.

Release of prostacyclin (PGI2) by the layers of corpus of rat stomach

Release of PGI2 by slices of muscularis and mucosa layers of rat corpus stomach was investigated. An anti-aggregatory substance that was released by slices of muscularis was identified as PGI2 in various bioassay systems including anti-serum against PGI2 as well as by stimulation of its generation with AA or PGH2 and by inhibition of this generation with indomethacin or tranylcypromine, respectively. PGI2 was the major PGs released from slices of muscularis. The release of PGI2 from muscularis surpasses a similar release of PGI2 from mucosa by a factor of 10. On the other hand, degradation of exogenous PGI2 was 4 times faster by mucosa than by muscularis slices. Our conclusion is that in the stomach corpus wall of rats, muscularis is the main source of PGI2, which may play a role in regulation of mucosal blood flow.