• Journal of the Korean Chemical Society
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• v.57 no.5
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• pp.599-605
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• 2013

Some N-acetyl pyrazoles including 1-(3-(3,4-dichlorophenyl)-5-(substituted phenyl)-4,5-dihydro-$^1H$-pyrazole- 1-yl) ethanones have been synthesised by solvent free cyclization cum acetylation of chalcones like substituted styryl 3,4- dichlorophenyl ketones using hydrazine hydrate and acetic anhydride in presence of catalytic amount of fly-ash: $H_2SO_4$ catalyst. The yield of these N-acetyl pyrazole derivatives are more than 75%. The synthesised N-acetyl pyrazoline derivatives were characterized by their physical constants and spectral data.

• Archives of Pharmacal Research
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• v.17 no.5
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• pp.298-303
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• 1994

4-Arylazo-1H-pyrazol-3, 5-idimines 1a-c reacted with bromomalononitrile (2) to yield the corresponding imidazo[1, 2-b]pyrazoles 3a-c. The latter reacted with some active methylene compounds and with .alpha.-cinnamonitriles to afford the corresponding pyrazoloimidazopyridines 6, 8, 9 and 15, respectively. Compounds 3 reacted with each of formic acid, formamide, trichlo-roacetonitrile and with guanidine to yield the corresponding pyrazoloimidazopyrimidines 16-19 respectively.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.256-261
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• 2011

A new series of bis acetylated hybrid pyrazoles were synthesized and characterized by their melting point, elemental analysis, MS, FT-IR, one-dimensional $^1H$, and $^{13}C$ NMR spectroscopic data. All the synthesized compounds were tested for their in vitro antifungal activities against Candida sp. namely Candida albicans, Candida glabrata, Candida parapsilosis, Candida dubliniensis and Candida tropicalis. A close inspection of the in vitro anticandidal activity profile in differently electron donating ($CH_3$ and $OCH_3$) and electron withdrawing (-F, -Cl, and Br) functional group substituted phenyl rings of novel hybrid pyrazoles exerted strong anticandidal activity against all the tested Candida species.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4366-4370
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• 2011

A simple, green and cost-effective protocol was used for the aromatization of 1,3,5-trisubstituted-2-pyrazolines to the corresponding pyrazoles by in situ generation of iodine ($I^+$) from $H_2O_2$/AcOH or SSA or oxalic acid /KI or NaI system under thermal condition with moderate to good yields.

• Archives of Pharmacal Research
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• v.24 no.3
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• pp.180-189
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• 2001

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-amino derivatives were prepared. Several of these compounds were screened for antiinflammatory, analgesic, antipyretic and ulcerogenic activities.

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.737-743
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• 2010

Coupling of 5-amino-1,3-diaryl-pyrazoles 1a-c with diazonium salts of different aryl amines gave a series of novel 1,3-diaryl-5-amino-4-arylazopyrazoles 3a-l. Such compounds could be also obtained by reaction of 5-amino-1,3-diaryl-4-nitroso- 1H-pyrazoles 2a-c with different aryl amines in alkaline medium. Oxidation of azo derivatives 3a-l with cupric acetate, in dimethyl formamide and stream of air, gave 2,4,6-triaryl-2,4-dihydropyrazolo [4,3-d]-1,2,3-triazoles 4a-l. and the fluorescence properties of the cyclic triazoles were studied. Diazotization of 5-amino-1,3-diaryl-1H-pyrazoles 1a-c by sodium nitrite in ortho-phosphoric acid followed by coupling with some aryl amines gave o-aminoazo compounds 5a-f. Cyclisation of compounds 5a-f in pyridine and cupric acetate gave the corresponding triazoles 6a-f. The coupling of compounds 6a-f with different aryl diazonium salts gave compounds 7a-j. The synthesized dyes were applied to polyesters as disperse dyes and the fastness properties were evaluated.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3629-3634
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• 2012

A series of new 4-(pyridin-4-yl)-(3-methoxy-5-methylphenyl)-1H-pyrazoles (6a-k & 7a-l) has been rationally designed based on the structure of the lead compound KIST301080, a selective ROS receptor tyrosine kinase inhibitor, in order to study the activity of ROS of this new class of inhibitors. The compounds were synthesized and screened against ROS kinase, where compound 6h showed moderate inhibitory activity with an $IC_{50}$ value of $6.25{\mu}M$. The study emphasized the importance of the acetonitrile group at the pyrazole ring and also the importance of having a hydrogen bond donor on the distal phenyl ring linked to the pyridine moiety.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.437-442
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• 2013

A new series of 4-(2-(substituted)pyridin-4-yl)-3-(3-methoxy-5-methylphenyl)-1H-pyrazoles (4a-f) and their 1,2-isoxazole analogues (5a-f) has been rationally designed, synthesized and screened against both ROS and MAPK14 kinases. Compounds 4b, 4c and 4e showed moderate inhibitions against both ROS and MAPK14 kinases. Compound 4e has showed the strongest inhibitions with IC50 values of 1.25 ${\mu}M$ and 3.00 ${\mu}M$ against ROS and MAPK14 kinases, respectively. A brief structure-activity relationship study and a molecular modeling study were made revealing a group of essential structural features for good kinase inhibitory activity within this new class of kinase inhibitors.

• Archives of Pharmacal Research
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• v.17 no.4
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• pp.278-280
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• 1994

1,5-diketones(3) undewent cyclization to 4H-pyrano[3,2-d]pyrazoles (4a-d),4H-piperidino[3, 2-d]pyrazole (5) and pyrazolo[5,4-d]thiopyran (6) upon treatment with P/sub 2/O/sub 5/, CH/sub 3/COONH/sub 4/ and /or P/sub 2/S/sub 5/. Moreover, treatment of (4) with CH/sub 3/COONH/sub 4/ and/or P/sub 2/S/sub 5/ afforded (5) and (6). The structures of the hitherto unknown ring systems have been confirmed by analytical and spectral data.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2915-2920
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• 2013

Convenient synthetic method for 4-arylethylpyrazoles and 4-styrylpyrazoles was developed using ${\alpha}$-alkenyl-${\alpha},{\beta}$-enones readily accessed from the Morita-Baylis-Hillman reaction. For the synthesis of 4-arylethylpyrazole, the reactions with arylhydrazines needed to be carried out in o-dichlorobenzene under $N_2$ balloon atmosphere. On the other hand, 4-styrylpyrazoles required the reactions in ethanol under $O_2$ balloon atmosphere.