Understanding the mode of action of a pterostilbene derivative as anti-inflammatory agent.

Inflammatory response plays an important role not only in the normal physiology, but also in the pathology of certain diseases such as cancers. In our previous study, we found a novel derivative of pterostilbene (PTER), to be an effective inducer of apoptosis in human breast and prostate cancer cells affecting various cellular targets. Herein, we further attempted to investigate its anti-inflammatory potential followed by its probable mode of action. The newly developed compound was tested for its anti-inflammatory actions in lipopolysaccharide (LPS) stimulated RAW264.7 macrophages and carrageenan induced rat paw edema models. Our data showed that the derivative inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) as well as the downstream products like nitric oxide (NO) and PGE2, at much lower doses as compared to PTER. This effect was found to be associated with the inhibition of phosphorylation/degradation of IκB-α and nuclear translocation of the p-NFκB p65. Moreover, inhibition of mitogen-activated protein kinases (MAPKs) and activator protein-1 (AP-1) was also observed. In addition, the newly developed compound also reduced the paw edema, the tissue content of NO, PGE2 and expression of iNOS and COX-2 proteins within the tissues after λ-carrageenan stimulation. Taken together, our findings provide the possibility that the PTER derivative might have enhanced cancer chemopreventive potential based on its stronger anti-NFκB and anti-inflammatory activities as compared to its natural counterpart, i.e., PTER. Thus, this compound can be used towards the development of an effective anti-inflammatory agent.

Synthesis, anti-inflammatory, and antiproliferative activity evaluation of isoindole, pyrrolopyrazine, benzimidazoisoindole, and benzimidazopyrrolopyrazine derivatives.

A number of isoindole (3x, 3y, 6xa-6ye), pyrrolopyrazine (3z, 6za-6ze), benzimidazoisoindole (4x, 4y, 7xa-7ye), and benzimidazopyrrolopyrazine (4z, 7za-7ze) derivatives has been synthesized in excellent yields. All these compounds were fully characterized and evaluated against five human cancer cell lines for their anti-inflammatory and antiproliferative activity. Compounds 6yc and 7zd exhibited good anti-inflammatory activity whereas compounds 6zc, 7zd (lung NCl H-522), 6ye, 7xd, 7yd, 7zc, 7zd (colon HCT-15), 6xc, 7zc (ovary PA-1), 6xc, 6yb, 6zc (liver HepG-2) exhibited good antiproliferative activity.

Solvent free synthesis, anti-inflammatory and anticancer activity evaluation of tricyclic and tetracyclic benzimidazole derivatives.

Heterocyclic benzimidazole derivatives 3a-h, 5a-c and 7a-d have been synthesized by condensation of succinic acid (1) homophthalic acid (4) and 2,3-pyrazinedicarboxlic acid (6) with various substituted diamines under microwave irradiation in good yields. Structures assigned to 3a-h, 5a-c and 7a-d are fully supported by spectral data. All these compounds were screened for anti-inflammatory and anticancer activities. At a dose of 50 mg/kg p.o. compounds 3b (39.4%) and 3c (39.2%) exhibited anti-inflammatory activity, comparable to standard ibuprofen which showed 39% activity at 50 mg/kg p.o. and compound 7c exhibit good anticancer activity against ovary (IGR-OV-1), breast (MCF-7) and CNS(SF-295) human cancer cell lines.

Conventional and microwave assisted synthesis of small molecule based biologically active heterocyclic amidine derivatives.

Heterocyclic amidine derivatives have been synthesized by condensation of 2-cyanopyrazine, 4-cyanopyridine and 2-cyanopyridine with furfurylamine, histamine, 1-(3-aminopropyl)imidazole, 4-picolylamine, 2-picolylamine, and tryptamine respectively, in the presence of sodium methoxide as well as via microwave irradiation in good yields. All these compounds were screened for anti-inflammatory and anticancer activities. At a dose of 50mg/kg p.o. compounds 3a (36.6%), 3d (32%), 4d (31.0%) and 4e (33.8%) exhibited good anti-inflammatory activity, comparable to standard drug ibuprofen which showed 39% activity at 50mg/kg p.o.

Synthesis, anti-inflammatory and anticancer activity evaluation of some novel acridine derivatives.

Condensation of 9-chloro-2,4-(un)substituted acridines (1a-c) with various amines (2a-e) and 9-isothiocyanato-2,4-(un)substituted acridines (4a,b) with different amines (2a,b,d,e) gave condensed products 3a-o and 5a-g respectively. Compounds 3a-o and 5a-g were screened for anti-inflammatory activity at a dose of 50mg/kg p.o. Compound 3e exhibited 41.17% anti-inflammatory activity which is better than most commonly used standard drug ibuprofen which showed 39% anti-inflammatory (at 50mg/kg p.o.) activity. Anticancer activity evaluation of compounds 3a-o and 5a-g was carried out against a small panel of human cancer cell lines and compounds 3g, 3m and 5g exhibited good anticancer activity against breast (MCF-7), liver (HEP-2), colon (COLO-205, 502713, HCT-15), lung (A-549) and neuroblastoma (IMR-32) cancer cell lines at a concentration of 1 x 10(-5)M.

Synthesis, anticancer, and anti-inflammatory activity evaluation of methanesulfonamide and amidine derivatives of 3,4-diaryl-2-imino-4-thiazolines.

Condensation of 3,4-diaryl-2-imino-4-thiazoli-nes 1a-j with methanesulfonyl chloride gave methanesulfonamide derivatives 2a-j. Condensation of 2-cyanopyrazine, 4-cyanopyridine, and 2-cyanopyridine with 3,4-diaryl-2- imino-4-thiazolines 1h-m in the presence of sodium methoxide afforded amidine derivatives 3a-j. Compounds 2a-j and 3a-j were screened against various human cancer cell lines (COLO-205, HEP-2, A-549, IMR-32) and their percentage growth inhibition profile determined at 1 x 10(-5)M. The anti-inflammatory activity of these compounds was assessed using the carrageenan-induced paw edema model. Compound 2i exhibited 34.7% anti-inflammatory activity at 50 mg/kg p.o., which is comparable to standard care drug phenyl butazone (37% activity at 50 mg/kg p.o.).

Microwave-assisted synthesis of N-substituted cyclic imides and their evaluation for anticancer and anti-inflammatory activities.

A number of N-substituted cyclic imides 3a-e, 5a-e, 7a-d, and 9a-e have been synthesized in very high yields, by condensation of various diacids 2, 4, 6, and 8 with different amines under microwave irradiation. These compounds were screened for anticancer and anti-inflammatory activities, and compounds 3c, 3e, 5c, 9c, and 9d exhibited anticancer activity against colon (COLO 205) cancer better than 5-fluorouracil and mitomycin-C, and compound 9b exhibited anti-inflammatory activity better than standard drug phenyl butazone.

Synthesis of amidine and amide derivatives and their evaluation for anti-inflammatory and analgesic activities.

A number of amidine derivatives (2a-i) have been synthesized by condensation of 2-cyanopyridine with various 3,4-diaryl-2-imino-4-thiazolines. Various amide derivatives (3a-h) were synthesized by condensation of orotic acid and hydantoin-5-acetic acid with a number of 3,4-diaryl-2-imino-4-thiazolines using microwave irradiation. All the compounds i.e. (2a-i) and (3a-h) synthesized were characterized by spectroscopic means and elemental analysis. Compounds (2a-i) and (3a-h) at 50 mg/kg p.o. were screened for anti-inflammatory activity whereas 2a-d, f, g, i and 3a, b, d, f at 50 mg/kg p.o. were evaluated for analgesic activity. Compounds 2e and 3g exhibited good anti-inflammatory activity (49% and 34%, respectively) and 2f, g showed interesting (50% in each case) analgesic activity.

Synthesis of some thiophene, imidazole and pyridine derivatives exhibiting good anti-inflammatory and analgesic activities.

A series of thiophene derivatives 1a-d & 2a-c were synthesized by condensation of 5-nitro-2-thiophene carboxaldehyde with mono and diamines respectively. Various imidazole derivatives 3a-c were obtained by condensing 4-(2-ethylamino)-1H-imidazole with 4-acetylpyridine, 2-acetylpyridine and 4-acetylbenzonitrile respectively. Pyridine derivatives 4a-e were synthesized by condensing 2-hydrazino-pyridine with various carbonyl compounds; 5a-c by condensing 2, 6-pyridine dicarbonyl dichloride with various aryl sulfonylhydrazides; 6, 7 by condensing 2, 6-dialdehyde pyridine with 2-hydrazinopyridine and anthranilonitrile respectively and compound 8 by condensing 2, 5-thiophene dialdehyde with hydrazinopyridine. All the compounds were characterized by IR, (1)HNMR, Mass spectra and elemental analysis. Compounds 1a-d; 2a-c; 3a-c; 4a-e; 5a-c, 6, 7 and 8 were screened for anti-inflammatory and analgesic activities. Compounds 1b and 2c exhibited good anti-inflammatory (26.5% and 33.4% at 50mg/kg p.o. respectively) and 3a, 3c good analgesic (100% and 75% at 100 mg/kg p.o. respectively) activities.

Synthesis of biologically active N-methyl derivatives of amidines and cyclized five-membered products of amidines with oxalyl chloride.

A series of substituted N-methylisonicotinamidine (2a-f), N-methylpyrazine-2-carboxamidine (2g-i) derivatives were synthesized by reaction of amidine derivatives (1a-i) with methyl iodide in presence of triethylamine. Five-membered condensed dihydroimidazolylbenzenesulfonamide derivatives (3a-i) were obtained by the reaction of amidine derivatives (1a-i) with acylating agent oxalyl chloride. All the compounds, i.e. 2a-i and 3a-i were purified by crystallization. Structures of all the synthesized compounds are supported by correct IR, (1)H NMR, mass spectral and analytical data. Anti-inflammatory activity evaluation was carried out using carrageenan-induced paw oedema assay and compounds 2e, 3a and 3d exhibited good anti-inflammatory activity (44%, 31% and 37% activity at 50 mg/kg p.o., respectively). Analgesic activity evaluation was carried out using acetic acid writhing assay and compounds 2a and 3f gave 75% activity each at 100 mg/kg p.o.; on the other hand compounds 3a and 3d exhibited 60% analgesic activity each at 50 mg/kg p.o. Compounds 3a and 3d exhibited good anti-inflammatory and analgesic activities.

One pot synthesis of pyrimidine and bispyrimidine derivatives and their evaluation for anti-inflammatory and analgesic activities.

A number of pyrimidine derivatives (1-10) have been synthesized by condensation of 4-isothiocyanato-4-methylpentan-2-one with furfurylamine, histamine, 1-(3-aminopropyl)imidazole, 1-(3-aminopropyl)-2-pyrrolidinone, 2-aminobenzonitrile and 3-isothiocyanatobutanal with 1-(3-aminopropyl)-2-pyrrolidinone and 2-hydrazinopyridine under different reaction conditions. Various bispyrimidine derivatives (11-15) were obtained by condensation of 4-isothiocyanato-4-methylpentan-2-one with 2,4,8,10-tetraoxaspiro[5,5]undecane3,9-dipropamine (11'), 1,4-bis(3-aminopropyl)piperazine (13'), 3,5-diamino 1,2,4-triazole (15') and 3-isothiocyanatobutanal with 2,4,8,10-tetraoxaspiro[5,5]undecane 3,9-dipropamine, 1,4-bis(3-aminopropyl)piperazine. All these compounds were characterized by correct FT-IR, (1)H NMR, MS and elemental analysis. These compounds were screened for anti-inflammatory and analgesic activities. Anti-inflammatory activity of 3 is comparable while analgesic activity was found to be better than that of standard drug.

Synthesis, anti-inflammatory and analgesic activity evaluation of some amidine and hydrazone derivatives.

A number of amidine derivatives (3a-i) were synthesized by condensation of cyanopyridine and cyanopyrazine with sulfonylhydrazides in the presence of sodium methoxide. 2-Acetylpyridine and 4-acetylpyridine were condensed with sulfonylhydrazides by microwave irradiation in solid phase to give corresponding hydrazones (5a-d). Indole-3-carboxaldehyde was condensed with sulfonylhydrazides by refluxing in acetic acid to give corresponding condensation product (5e and f). All the compounds, that is, 3a-i and 5a-f were purified by crystallization or by column chromatography. Structures of all the synthesized compounds are supported by correct IR, (1)H NMR, mass spectral and analytical data. Anti-inflammatory activity evaluation was carried out using carrageenin-induced paw oedema assay and compounds 3e,f and 5e exhibited good anti-inflammatory activity, that is 52%, 37% and 38% at 50 mg/kg po, respectively. Analgesic activity evaluation was carried out using acetic acid writhing assay and compounds 3a,c,e and 5f showed good analgesic activity, that is, 50%, 50%, 50% and 60% at 50 mg/kg po, respectively.

Synthesis, anti-inflammatory, analgesic and kinase (CDK-1, CDK-5 and GSK-3) inhibition activity evaluation of benzimidazole/benzoxazole derivatives and some Schiff's bases.

A series of N-(acridin-9-yl)-4-(benzo[d]imidazol/oxazol-2-yl) benzamides has been synthesized by the condensation of 9-aminoacridine derivatives with benzimidazole or benzoxazole derivatives. Condensation of 2-hydroxy naphthaldehyde with functionalized diamines leads to the formation of Schiff's bases and not imidazole derivatives. All these compounds were characterized by correct FT-IR, (1)H NMR, MS and elemental analyses. These compounds were screened for anti-inflammatory, analgesic and kinase (CDK-1, CDK-5 and GSK-3) inhibition activities. Compounds 11 and 7e(f) showed good anti-inflammatory (35.8% at 50 mg/kg po) activity and good analgesic activity (60% at 50 mg/kg po), respectively. Compound 3b showed significant in vitro activity against CDK-5 (IC(50)=4.6 microM) and CDK-1(IC(50)=7.4 microM) and compound 3a showed moderate CDK-5 inhibitory activity (IC(50)=7.5 microM). The other compounds showed moderate anti-inflammatory and analgesic activities.

Synthesis, anti-inflammatory and analgesic activities evaluation of some mono, bi and tricyclic pyrimidine derivatives.

3-Aminobenzonitrile and 2-amino-4-phenyl thiazole on condensation with 4-isothiocyanato-4-methyl pentane-2-one gave condensed monocyclic pyrimidine derivatives 1 and 2, 3, respectively. Condensation of 3-aminopropyl imidazole with 3-isothiocyantobutanal gave condensed monocyclic pyrimidine derivative 4. Bicyclic pyrimidine derivatives 5a and 5b have been synthesized by the condensation of diaminomaleonitrile with 4-isothiocyanto-4-methylpentane-2-one and 3-isothiocyanatobutanal, respectively. Condensation of 4-isothiocyanato-4-methyl pentane-2-one with 2,3-diaminopropionic acid hydrochloride yielded another bicyclic compound 7. 4-Isothiocyanato-4-methyl pentane-2-one, 3-isothiocyanatobutanal and 4-isothiocyanatobutan-2-one on condensation with 2-amino-4-nitro phenol gave tricyclic pyrimidine derivatives 8a, 8b and 8c, respectively. Structures of all the synthesized pyrimidine derivatives are supported by correct IR, 1H NMR and mass spectral data. The anti-inflammatory activity evaluation was carried out using carrageenin-induced paw oedema assay, and compounds 1, 3 and 5b exhibited good anti-inflammatory activity, that is, 27.9, 34.5 and 34.3% at 50 mg/kg po, respectively. Analgesic activity evaluation was carried out using phenylquinone writhing assay and compounds 5a, 5b and 8b showed good analgesic activity, that is, 50, 70 and 50% at 50 mg/kg po, respectively.

Synthesis of acridinyl-thiazolino derivatives and their evaluation for anti-inflammatory, analgesic and kinase inhibition activities.

Variety of N-(4-phenyl-3-(2',3',4'(un)substituted phenyl)thiazol-2(3H)-ylidene)-2,4(un)substituted acridin-9-amine (4a-o) and 1-[(2,4-(un)substituted acridin-9-yl)-3-(4-phenyl-3-(2',3',4'(un)substituted phenyl)thiazol-2(3H)-ylidene)]isothiourea (5a-h) derivatives have been synthesized by condensation of 4-phenyl-3-(2',3',4'(un)substituted phenyl)thiazol-2(3H)-imine (3a-g) with 9-chloro-2,4-(un)substituted acridine (1a-c) and 9-isothiocyanato-2,4-(un)substituted acridine (2a-d), respectively. All these compounds were characterized by correct 1H NMR, FT-IR, MS and elemental analyses. These compounds were screened for anti-inflammatory, analgesic and kinase (CDK1, CDK5 and GSK3) inhibition activities. Some compounds exhibited good anti-inflammatory (25-32%) and potent analgesic (50-75%) activities, at 50 mg/kg p.o. A compound, 4o (R1 = H, R2 = OCH3, R3 = CH3, R4 = CH3, R5 = H) exhibited moderate CDK1 (IC50 = 8.5 microM) inhibition activity.

Synthesis and biological evaluation of 2-thiopyrimidine derivatives.

Various 2-thiopyrimidine derivatives have been synthesized by an efficient, one-pot reaction of functionalized amines with either 4-isothiocyanato-4-methyl-2-pentanone or 3-isothiocyanatobutanal. All the synthesized compounds were fully characterized by elemental analysis (CHN), FT-IR, (1)H NMR, and mass spectral data. One of the compounds, 7,7,8a-trimethyl-hexahydro-thiazolo[3,2-c]pyrimidine-5-thione (17) showed good anti-inflammatory (37.4% at 100 mg/kg p.o.) and analgesic activity (75% at 100 mg/kg p.o.). 7-(1-Mercapto-3,3,4a-trimethyl-4,4a,5,9b-tetrahydro-3H-pyrido[4,3-b]indol-7-yl)-3,3,4a-trimethyl-3,4,4a,5-tetrahydro-benzo[4,5]imidazo[1,2-c]pyrimidine-1-thiol (3) showed moderate activity against CDK-1 (IC(50)=5 microM). The other compounds showed moderate anti-inflammatory (5-20%), analgesic (25-75%) and protein kinase (CDK-5, GSK-3) inhibitory activities (IC(50)> 10 microM).

Anti-inflammatory, analgesic and antiamoebic activity evaluation of pyrimido[1,6-a]benzimidazole derivatives synthesized by the reaction of ketoisothiocyanates with mono and diamines.

(UN) substituted o-phenylenediamines 1a-g reacted with 3-isothiocyanatobutanal to give pyrimidobenzimidazole derivatives, 2a-g, respectively. Products 4, 6 and 8, 10 were obtained by condensation of 3-isothiocyanatobutanal with 2,3-diaminopyridine, 1,4-diaminobutane and 3-isothiocyanatopropanal with 4,5-dimethyl-1,2-phenylenediamine, o-nitroaniline, respectively. S-Methylation of 2f and 11b gave products 12a and 12b, respectively. Anti-inflammatory and analgesic activity evaluations of 2a-g and 12b were carried out at 50 mg kg(-1) p.o. Compound 2c exhibited good anti-inflammatory (46%) and mild analgesic activity (50%). Antiamoebic activity evaluations (using microdilution method) of 2a-g against Entamoeba-histolytica (strain HM1: IMSS) were carried out and compounds 2a, 2b, 2d and 2g exhibited good antiamoebic activity in vitro.

Heterocyclic compounds as inflammation inhibitors.

Clinical use of non-steroidal anti-inflammatory drugs (NSAIDs) is associated with significant toxicity particularly in the gastrointestinal tract and kidney. Various approaches such as formulation co-administration (of agents to protect the stomach), chemical manipulation and synthesis of new safer anti-inflammatory drugs reported in the literature to overcome the toxicity of NSAIDs have been summarized. As far as synthesis of new more effective and safer anti-inflammatory drugs is concerned, we have reported recent findings in the area of synthesis of heterocyclic compounds such as pyrimidines, imidazole, benzimidazole, thiazole, thiazolidine, acridine, thiourea, alkanoic acid derivatives and other related heterocyclic compounds and their role as inflammation inhibitors.