Rational Design and Synthesis of New Selective COX-2 Inhibitors with In Vivo PGE2-Lowering Activity by Tethering Benzenesulfonamide and 1,2,3-Triazole Pharmacophores to Some NSAIDs.

New selective COX-2 inhibitors were designed and synthesized by tethering 1,2,3-triazole and benzenesulfonamide pharmacophores to some NSAIDs. Compounds 6b and 6j showed higher in vitro COX-2 selectivity and inhibitory activity (IC50 = 0.04 µM and S.I. = 329 and 312, respectively) than celecoxib (IC50 = 0.05 µM and S.I. = 294). Compound 6e revealed equipotent in vitro COX-2 inhibitory activity to celecoxib. Furthermore, 6b and 6j expressed more potent relief of carrageenan-induced paw edema thickness in mice than celecoxib, with ED50 values of 11.74 µmol/kg and 13.38 µmol/kg vs. 16.24 µmol/kg, respectively. Compounds 6b and 6j inhibited the production of PGE2 with a % inhibition of PGE2 production of 90.70% and 86.34%, respectively, exceeding celecoxib's percentage (78.62%). Moreover, 6b and 6j demonstrated a gastric safety profile comparable to celecoxib. In conclusion, compounds 6b and 6j better achieved the target goal as more potent and selective COX-2 inhibitors than celecoxib in vitro and in vivo.

Rational design of biodegradable sulphonamide candidates treating septicaemia by synergistic dual inhibition of COX-2/PGE2 axis and DHPS enzyme.

A new series of co-drugs was designed based on hybridising the dihydropteroate synthase (DHPS) inhibitor sulphonamide scaffold with the COX-2 inhibitor salicylamide pharmacophore through biodegradable linkage to achieve compounds with synergistic dual inhibition of COX-2/PGE2 axis and DHPS enzyme to enhance antibacterial activity for treatment of septicaemia. Compounds 5 b, 5j, 5n and 5o demonstrated potent in vitro COX-2 inhibitory activity comparable to celecoxib. 5j and 5o exhibited ED50 lower than celecoxib in carrageenan-induced paw edoema test with % PGE2 inhibition higher than celecoxib. Furthermore, 5 b, 5j and 5n showed gastric safety profile like celecoxib. Moreover, in vivo antibacterial screening revealed that, 5j showed activity against S.aureus and E.coli higher than sulfasalazine. While, 5o revealed activity against E.coli higher than sulfasalazine and against S.aureus comparable to sulfasalazine. Compound 5j achieved the target goal as potent inhibitor of COX-2/PGE2 axis and in vivo broad-spectrum antibacterial activity against induced septicaemia in mice.

Expanding the anticancer potential of 1,2,3-triazoles via simultaneously targeting Cyclooxygenase-2, 15-lipoxygenase and tumor-associated carbonic anhydrases.

Cancer is a multifactorial disorder involving multiplicity of interrelated signaling pathways and molecular targets. To that end, a multi-target design strategy was adopted to develop some 1,2,3-triazoles hybridized with some pharmacophoric anticancer fragments, as first-in-class simultaneous inhibitors of COX-2, 15-LOX and tumor associated carbonic anhydrase enzymes. Results revealed that compounds 5a, 5d, 8b and 8c were potent inhibitors of COX-2 and 15-LOX enzymes. COX-2 inhibitory activity was further demonstrated by the inhibition of the accumulation of 6-keto-PGF1α, a metabolite of COX-2 products in two cancer cell lines. The sulfonamide bearing derivatives 5d and 8c were effective nanomolar and submicromolar inhibitors of tumor associated hCA XII isoform, respectively. Strong to moderate inhibitory activities were observed in the in vitro antiproliferative assay on lung (A549), liver (HepG2) and breast (MCF7) cancer cell lines (IC50 2.37-28.5 µM) with high safety margins on WI-38 cells. A cytotoxic advantage of CA inhibition was observed as an increased activity against tumor cell lines expressing CA IX/XII. Further mechanistic clues for the anticancer activities of compound 5a and its sulfonamide analog 5d were derived from induction of cell cycle arrest at G2/M phase. They also triggered apoptosis via increasing expression levels of caspase-9 and Bax together with suppressing that of Bcl-2. The in vitro anti-tumor activity was reflected as reduced tumor size upon treatment with 8c in an in vivo cancer xenograft model. Docking experiments on the target enzymes supported their in vitro data and served as further molecular evidence. In silico calculations and ligand efficiency indices were promising. In light of these data, such series could offer new structural insights into the understanding and development of multi-target COX-2/15-LOX/hCA inhibitors for anticancer outcomes.

Novel pyrazine based anti-tubercular agents: Design, synthesis, biological evaluation and in silico studies.

TB continues to be a leading health threat despite the availability of powerful anti-TB drugs. We report herein the design and synthesis of various hybrid molecules comprising pyrazine scaffold and various formerly identified anti-mycobacterial moieties. Thirty-one compounds were screened in vitro for their activity against Mycobacterium tuberculosis H37Rv strain using MABA assay. The results revealed that six compounds (8a, 8b, 8c, 8d, 14b and 18) displayed significant activity against Mtb with MIC values ≤6.25 µg/ml versus 6.25 µg/ml for pyrazinamide. The most active compounds were then assessed for their in vitro cytotoxicity against PBMC normal cell line using MTT assay and showed SI > 200. Several in silico studies have been carried out for target fishing of the novel compounds such as shape-based similarity, pharmacophore mapping and inverse docking. Based on this multi-step target fishing study, we suggest that pantothenate synthetase could be the possible target responsible for the action of these compounds. The most active compounds were then successfully docked into the active site of pantothenate synthetase enzyme with favorable binding interactions. In addition, in silico prediction of physicochemical, ADMET and drug-like properties were also determined indicating that compounds 8b, 8c and 8d are promising candidates for the development of new anti-TB agents with enhanced activity and better safety profile.

Synthesis of pyrazolo-1,2,4-triazolo[4,3-a]quinoxalines as antimicrobial agents with potential inhibition of DHPS enzyme.

AIM: The development of a new class of antimicrobial agents is the optimal lifeline to scrap the escalating jeopardy of drug resistance. EXPERIMENTAL: This study aims to design and synthesize a series of pyrazolo-1,2,4-triazolo[4,3-a]quinoxalines, to develop agents having antimicrobial activity through potential inhibition of dihyropteroate synthase enzyme. The target compounds have been evaluated for their in-vitro antimicrobial activity. RESULTS & DISCUSSION: Compounds 5b, 5c were equipotent (minimal inhibitory concentration = 12.5 µg/ml) to ampicillin. The docking patterns of 5b and 5c demonstrated that both fit into Bacillus Anthracis dihydropteroate synthase pterin and p-amino benzoic acid-binding pockets. Moreover, their physicochemical properties and pharmacokinetic profiles recommend that they can be considered drug-like candidates. The results highlight some significant information for the future design of lead compounds as antimicrobial agents.

Design, synthesis, antibacterial evaluation and molecular docking studies of some new quinoxaline derivatives targeting dihyropteroate synthase enzyme.

Development of new antimicrobial agents is a good solution to overcome drug-resistance problems. From this perspective, new quinoxaline derivatives bearing various bioactive heterocyclic moieties (thiadiazoles, oxadiazoles, pyrazoles and thiazoles) were designed and synthesized. The newly synthesized compounds were evaluated for their in vitro antibacterial activity against nine bacterial human pathogenic strains using the disc diffusion assay. In general, most of the synthesized compounds exhibited good antibacterial activities. The thiazolyl 11c displayed significant antibacterial activities against P. aeruginosa (MIC, 12.5 µg/mL vs levofloxacin 12.5 µg/mL). Molecular docking studies indicated that the synthesized compounds could occupy both p-amino benzoic acid (PABA) and pterin binding pockets of the dihydropteroate synthase (DHPS), suggesting that the target compounds could act by the inhibition of bacterial DHPS enzyme. The results provide important information for the future design of more potent antibacterial agents.

Design and synthesis of some new 2,3'-bipyridine-5-carbonitriles as potential anti-inflammatory/antimicrobial agents.

AIM: Inflammation may cause accumulation of fluid in the injured area, which may promote bacterial growth. Other reports disclosed that non-steroidal anti-inflammatory drugs may enhance progression of bacterial infection. RESULTS: This work describes synthesis of new series of 2,3'-bipyridine-5-carbonitriles as structural analogs of etoricoxib, linked at position-6 to variously substituted thio or oxo moieties. Biological screening results revealed that compounds 2b, 4b, 7e and 8 showed significant acute and chronic AI activities and broad spectrum of antimicrobial activity. In addition, similarity ensemble approach was applied to predict potential biological targets of the tested compounds. Then, pharmacophore modeling study was employed to determine the most important structural parameters controlling bioactivity. Moreover, title compounds showed physicochemical properties within those considered adequate for drug candidates. CONCLUSION: This study explored the potential of such series of compounds as structural leads for further modification to develop a new class of dual AI-antimicrobial agents.

New hybrid molecules combining benzothiophene or benzofuran with rhodanine as dual COX-1/2 and 5-LOX inhibitors: Synthesis, biological evaluation and docking study.

New molecular hybrids combining benzothiophene or its bioisostere benzofuran with rhodanine were synthesized as potential dual COX-2/5-LOX inhibitors. The benzothiophene or benzofuran scaffold was linked at position -2 with rhodanine which was further linked to various anti-inflammatory pharmacophores so as to investigate the effect of such molecular variation on the anti-inflammatory activity. The target compounds were evaluated for their in vitro COX/LOX inhibitory activity. The results revealed that, compound 5h exhibited significant COX-2 inhibition higher than celecoxib. Furthermore, compounds 5a, 5f and 5i showed COX-2 inhibitory activity comparable to celecoxib. Compound 5h showed selectivity index SI=5.1 which was near to that of celecoxib (SI=6.7). Compound 5h displayed LOX inhibitory activity twice than that of meclofenamate sodium. Moreover, compounds 5a, 5e and 5f showed significant LOX inhibitory activity higher than that of meclofenamate sodium. Compound 5h was screened for its in vivo anti-inflammatory activity using formalin-induced paw edema and gastric ulcerogenic activity tests. The results revealed that, it showed in vivo decrease in formalin-induced paw edema volume higher than celecoxib. It also displayed gastrointestinal safety profile as celecoxib. The biological results were also consistent with the docking studies at the active sites of the target enzymes COX-2 and 5-LOX. Also, compound 5h showed physicochemical, ADMET, and drug-like properties within those considered adequate for a drug candidate.

Design, synthesis and antimicrobial evaluation of methyl pyridyl-2,4- dioxobutanoates and some new derived ring systems.

This work describes the synthesis of new series of compounds derived from methyl pyridyl- 2,4-dioxobutanoates that contain pyridine ring attached to substituted bioactive heterocyclic moieties in order to investigate their preliminary in vitro antibacterial and antifungal activities. The results revealed that most of the tested compounds exhibited significant activity against P. aeruginosa. and E. coli. They also displayed considerable activity against S. aureus and B. subtilis. On the other hand, the compounds displayed moderate antifungal activity.

Design, synthesis and biological screening of some pyridinylpyrazole and pyridinylisoxazole derivatives as potential anti-inflammatory, analgesic, antipyretic and antimicrobial agents.

A series of substituted pyridinylpyrazole (or isoxazole) derivatives were synthesized and evaluated for their anti-inflammatory (AI) activity using formalin-induced paw edema bioassays. Their inhibitory activities of cyclooxygenase-1 and cyclooxygenase-2 (COX-1 and COX-2) were also determined. The analgesic activity of the same compounds was evaluated using rat-tail withdrawal technique. Their antipyretic activity was also evaluated. The results revealed that compounds 4a,b, 6a, 8a, 14c and 15a exhibited significant AI and analgesic activities. Compounds 5a, 6a and 8a displayed good antipyretic activity. Compounds 14c and 15a showed good COX-2 inhibitory activity and weak inhibition of COX-1. Additionally, the most active compounds were shown to have a large safety margin (ALD50 >300-400 mg / Kg) and minimal ulcerogenic potentialities when administered orally at a dose of 300 mg/Kg. Docking studies for 14c and 15a with COX-2 showed good binding profile. Antimicrobial evaluation proved that most of the compounds exhibited distinctive activity against the gram negative bacteria, P. aeruginosa and E coli.

Synthesis, antioxidant, anticancer and antiviral activities of novel quinoxaline hydrazone derivatives and their acyclic C-nucleosides.

The present investigation describes the synthesis of a new series of aldehydo-sugar-N-(3-phenylquinoxalin-2- yl)hydrazones 3a-d and their acyclic C-nucleoside analogs, 1-(4-phenyl-[1,2,4]triazolo[4,3-a]quinoxalin-1-yl)alditols 7ad by using 2-hydrazino-3-phenylquinoxaline 1 as key intermediate. The synthesized compounds were screened for their antioxidant activities by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging method. Compounds 3d and 7a, showed potent scavenging activities against ABTS(+) radicals and were found to be the most potent antioxidants described in this study. Out of the synthesized compounds, compounds 3d and 7a were selected by the National Cancer Institute for evaluation of their in vitro anticancer activity. Results revealed that compounds 3d and 7a exhibited non-selective broad spectrum activity against all cancer cell lines between 10(-6) to 10(-5) molar concentrations. Compound 3d showed the highest sensitivity against leukemia cell line HL-60 (TB) with GI50 of 5.15 µM, while compound 7a showed the highest sensitivity against ovarian cancer cell lines IGROV1 and OVCAR-4 with GI50 of 14.5 and 16.0 µM, respectively. In addition, compounds 3d and 7a showed TGI values of 72.2 and 96.3 µM, respectively against ovarian cancer cell line OVCAR-4. Furthermore, the target compounds were tested for antiviral activity against Herpes Simplex virus type-1 (HSV-1) using plaque reduction infectivity assay. The results indicated that compounds 3a-d and 7a exhibited very weak antiviral activity in comparison to Aphidicolin as a positive control.

Synthesis and biological evaluation of some novel thieno[2,3-d] pyrimidine derivatives as potential anti-inflammatory and analgesic agents.

A novel series of thienopyrimidine derivatives bearing various substituents or linked to various heterocyclic moieties through atoms spacers were prepared starting from 5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6- carboxamide potassium salt 3. Twelve out of the prepared compounds were selected and evaluated for their antiinflammatory activity using the formalin-induced paw edema and the turpentine oil-induced granuloma pouch bioassays using diclofenac sodium as a reference standard. The ulcerogenic effects and acute toxicity (ALD50) values of these compounds were also determined. In addition, the analgesic activity of the same compounds was evaluated using the rat tail withdrawal technique. The results revealed that compounds 5a, 13, 14b, 15a, 16a and 16b had high anti-inflammatory effect comparable to diclofenac sodium, whereas compounds 5a, 14a, 15a and 16a revealed pronounced analgesic activity that is equal or higher than that of the reference. All of the tested compounds revealed high GI safety profile and were well tolerated by the experimental animals with high safety margin (ALD50 > 3.0g/Kg).

Synthesis of some novel substituted purine derivatives as potential anticancer, anti-HIV-1 and antimicrobial agents.

In search of novel purine antimetabolites, a series of 8-substituted methylxanthine derivatives was prepared in order to explore their in vitro anticancer, anti-HIV-1 and antimicrobial activities. The target compounds include: 8-[(3-substituted-4-oxo-thiazolidin-2-ylidene)hydrazino]-1,3-dimethyl (or 1,3,7-trimethyl)-3,7-dihydropurine-2,6-diones 5a-e, 8-[(3,4-disubstituted 2,3-dihydrothiazol-2-ylidene)hydrazino]-1,3,7-trimethyl-3,7-dihydropurine-2,6-diones 6a-d and 8-(5-amino-3-arylpyrazol-1-yl)-1,3-dimethyl- (or 1,3,7-trimethyl)-3,7-dihydropurine-2,6-diones 7a-g. The in vitro anticancer results revealed that compound 5d exhibited a super sensitivity profile towards leukemia K-562 with a GI(50) value of <0.01 microM. Compound 7c showed significant activity against colon cancer HCT-15 and renal cancer CAKI-1 (GI(50) values of 0.47 and 0.78 microM, respectively). Compound 7a displayed high activity against colon cancer HCT-15 (GI(50 )= 0.8 microM). The anti-HIV-1 results indicated that compound 6b displayed a good reduction of viral cytopathic effect (56.69%). The antimicrobial results showed that compound 5a was four times more active than ampicillin against P. aerugenosa (MIC =or< 25 microg/mL), compound 5b had twice the activity of ampicillin, while compounds 5d, 7c and 7f were equipotent to ampicillin. On the other hand, compound 7a was equipotent to ampicillin against P. vulgaris (MIC = 50 microg/mL).

Synthesis of thiazolo[4,5-d]pyrimidine derivatives as potential antimicrobial agents.

In this study, we report the synthesis and antimicrobial evaluation of several new thiazolo[4,5-d]pyrimidine derivatives, namely 7-substituted amino-5-methyl-3-phenylthiazolo[4,5-d]pyrimidine-2(3H)-thiones 4a-e, 8, 13, 15, ethyl 2-cyano-2-(7-substituted-5-methyl-3-phenylthiazolo [4,5-d]-pyrimidin-2(3H)-ylidene)acetates 5a-b, 2-(7-substituted-5-methyl-3-phenylthiazolo[4,5-d]pyrimidin-2(3H)-ylidene)malononitriles 6a-b, 5-methyl-7-morpholino-3-phenylthiazolo[4,5-d] pyrimidine-2(3H)-one 7, and 7-[4-(1-substituted-5-phenyl-4,5-dihydro-1H-pyrazolin-3-yl)anilino]-5-methyl-3-phenylthiazolo[4,5-d]pyrimidine-2(3H)-thiones 10-12. Some of the tested compounds were more active against C. albicans than E. coil and P. aeruginosa, and all were inactive against S. aureus.

Synthesis of novel benzofuran and related benzimidazole derivatives for evaluation of in vitro anti-HIV-1, anticancer and antimicrobial activities.

Previously, we synthesized and evaluated several benzofuran derivatives containing heterocyclic ring substituents linked to the benzofuran nucleus at C-2 by a two- to four-atom spacer as potential anti-HIV-1, anticancer and antimicrobial agents. Among these derivatives, NSC 725612 and NSC 725716 exhibited interesting anti-HIV-1 activity. To further investigate the structure-activity relationship, we synthesized several new benzofuran derivatives derived from 2-acetylbenzofuran (2, 3a-c) and 2-bromoacetylbenzofuran (6; 7a,b; 8a,b). The compounds were designed to comprise the heterocyclic substituents directly linked to the benzofuran nucleus at C-2. Moreover, various related benzimidazoles derived from 2-acetylbenzimidazole and from 2-cyanomethylbenzimidazole (12a,b; 13a,b; 15; 16a,b) were also prepared as isosteres. The synthesized compounds were preliminarily evaluated for their in vitro anti-HIV-1, anticancer and antimicrobial activity. Compounds 2, 3a, 3b, and 12b showed weak anti-HIV-1 activity. Compound 6 exhibited mild activity against S. aureus, while compound 15 had mild activity towards S. aureus and C. albicans. However, no significant anticancer activity was observed with any of the tested compounds. From these results, we conclude that the presence of the spacer between the heterocyclic substituent and the benzofuran nucleus may be essential for the biological activity.

Synthesis of some new quinoxalines and 1,2,4-triazolo[4,3-a]-quinoxalines for evaluation of in vitro antitumor and antimicrobial activities.

Two novel series of quinoxalines derived from 3-phenylquinoxalin-2(1H)-one and 2-hydrazino-3-phenylquinoxaline, namely 1-substituted-3-phenylquinoxaline-2(1H)-ones, 2a-c, 3a-d, and 4; 2-(3-oxo-3,3a,4,5,6,7-hexahydroindazol-2-yl)-3-phenylquinoxaline 6; N- cyclopentylidene or benzylidene-N'-(3-phenylquinoxaline-2-yl)hydrazines, 7 and 18; 1-substituted-4-phenyl-1,2,4-triazolo[4,3-a]quinoxalines, 9, 10, 12, 13, 14, and 16 have been synthesized in order to evaluate their antitumor and antimicrobial activities. Preliminary screening at NCI showed that compounds 2b, 2c, 3b, 3c, and 9 exhibited a moderate to strong growth inhibition activity on various tumor panel cell lines between 10(-6) to 10(-5) molar concentrations. Compound 3b was the most active with a broad spectrum of activity. Compound 3c showed selectivity towards CNS-cancer SF-639, leukemia CCRF-CEM, and melanoma SK-MEL-5 (GI(50) = 4.03, 6.46, and 4.17 microM, respectively). On the other hand, the in vitro microbiological data revealed that the prepared compounds showed mild antimicrobial activity.

Synthesis and in vitro-anticancer and antimicrobial evaluation of some novel quinoxalines derived from 3-phenylquinoxaline-2(1H)-thione.

Two novel series derived from 3-phenylquinoxaline-2(1H)-thione 2 and 2-(hydrazinocarbonylmethylthio)-3-phenylquinoxaline 6 have been synthesized. Eight out of twenty six new compounds were selected at the National Cancer Institute for evaluation of their in vitro-anticancer activity. Among them, compounds 3b, 3c, 4b, and 4c displayed moderate to strong growth inhibition activity against most of the tested sub-panel tumor cell lines with GI(50) 10(-5) to 10(-6 )molar concentrations. Compound 4b exhibited a significant value of percent tumor growth inhibition against breast cancer at concentration < 10(-8) M. Compound 4c showed moderate selectivity towards leukemia cell lines with GI(50) of 1.8 to 3.8 microM (selectivity ratio = 5.7). Preliminary antimicrobial testing revealed that compounds 7a, 7b, 8a, 11a, and 11b were as active as ampicillin against B. subtilis (MIC = 12.5 microg/mL). Compounds 7b and 8a were also nearly as active as ampicillin against E. coli (MIC = 12.5 microg/mL). In addition, compounds 4a, 7b, 10b, and 11a were as active as ampicillin against P. aerugenosa (MIC = 50 microg/mL). However, compounds 7b, 8a, and 10b showed mild activity against C. albicans (MIC = 50 microg/mL). The values of minimum bactericidal concentrations indicated that compounds 4a and 7b were bactericidal against B. subtilis and P. aerugenosa, respectively, while compound 10b was bactericidal against both organisms. However, compound 11a was bactericidal against E. coli, P. aerugenosa, and S. aureus.

Synthesis and in vitro evaluation of some novel benzofuran derivatives as potential anti-HIV-1, anticancer, and antimicrobial agents.

A novel series of 1-(1-benzofuran-2-yl-ethylidene)-4-substituted thiosemicarbazides (2a-d) along with some derived ring systems: substituted-2,3-dihydro-thiazoles (3a-c, 4a-f) and thiazolidin-4-ones (5a-d and 6a-d), were synthesized. In addition, cyanoacetic acid-(1-benzofuran-2-yl-ethylidene) hydrazide (7) was used to prepare another new series of compounds consisting of substituted pyridin-2(1H)-ones (8a-c); 2-thioxo-2,3-dihydro-thiazoles (9a-d) and 2-thioxo-2,3-dihydro-6H-thiazolo[4,5-d]pyrimidin-7-ones (10a-c, 11a-c). The absolute configuration of compound 5c was determined by X-ray crystallography. The compounds prepared were evaluated for their in vitro anti-HIV, anticancer, antibacterial, and antifungal activities. Among the tested compounds, compounds 5c and 9a produced a significant reduction [symbols, see text] the viral cytopathic effect (93.19% and 59.55%) at concentrations > 2.0 x 10(-4) M and 2.5 x 10(-5) M respectively. Compound 9a was confirmed to have moderate anti-HIV activity. Compounds 2a, 2d, and 5c showed mild antifungal activity. However, none of the tested compounds showed any significant anticancer activity.

Cyanoacetic acid hydrazones of 3-(and 4-)acetylpyridine and some derived ring systems as potential antitumor and anti-HCV agents.

Two new acetylpyridinehydrazones derived from cyanoacetic acid hydrazide have been synthesized namely: cyanoacetic acid (1-pyridin-3 or 4-yl-ethylidene) hydrazides (1a,b). and some derived ring systems: 2-imino or 2-oxo-2H-chromenes (2a,b and 3a,b), substituted 2-thioxo-2,3-dihydrothiazoles (4a-d), substituted 2-thioxo-2,3-dihydro-6H-thiazolo[4,5-d]pyrimidin-7-ones (5a-d), substituted dihydrothiazoles (7a,b), and substituted 2-oxo-1,2-dihydropyridines (8a-d and 9a,b). Fifteen compounds were evaluated for their anticancer activity using the USA-NCI in-vitro screening program. Among the tested compounds, 8d exhibited a high value of percent tumor growth inhibition at concentrations of 10(-5) to 10(-7) M in all cancer cell lines, while 8b exhibited a significant value of percent tumor growth inhibition at concentration <10(-8 )M against non-small cells lung HOP-92. In addition, nine compounds were investigated for their in-vitro effect on the replication of hepatitis-C virus (HCV) in HepG2 hepatocellular carcinoma cell line infected with the virus using the reverse transcription polymerase chain reaction technique. Six compounds were capable of inhibiting the replication of both the HCV RNA (+)- and (-)-strands at 5-100 microg/mL concentration range. The activity order was 7b > 1b = 3a > 4c > 7a > 5c.

Nonsteroidal antiinflammatory agents-part 2 antiinflammatory, analgesic and antipyretic activity of some substituted 3-pyrazolin-5-ones and 1,2,4,5,6,7-3H-hexahydroindazol-3-ones.

As a part of a research project on the synthesis of a number of substituted 1-(pyrimidin-2-yl)-3-pyrazolin-5-ones and 2-(pyrimidin-2-yl)hexahydroindazol-3-ones and as a result of the interesting antiinflammatory, analgesic and antipyretic activities recorded for some of these compounds, some new 3-pyrazolin-5-ones and hexahydroindazol-3-ones linked to substituted imidazolyl, pyrimidyl and tetrahydroquinazolinyl moieties were prepared and evaluated for such activity (). A structure-activity relationship (SAR) comparative study indicated that some compounds from 3-pyrazolin-5-one (2, 6-8, 10) and indazolone (18, 20, 24, 27, 29) series exhibited pronounced antiinflammatory, analgesic and antipyretic activities relative to indomethacin. Most of these compounds were found to be nearly equipotent in the antiinflammatory screen (ED(50)=16.8-19.9 mg/kg) whereas the lead compound, 2-indazolyl-4-pyrimidineacetic acid 24 (), was found to be the most potent among this series (ED(50)=9.9 mg/kg). Additionally, the most active compounds were shown to have a large safety margin (ALD(50)=3.0 g/kg, po) and devoid of ulcerogenic potentialities when administered orally at a dose of 300 mg/kg.