• Bulletin of the Korean Chemical Society
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• v.19 no.3
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• pp.299-307
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• 1998

PM3 semiempirical calculations were carried out to study the frequency-dependent nonlinear optical properties of thiophene, furan, pyrrole, (1,2,4)-triazole, (1,3,4)-oxadiazole, and (1,3,4)-thiadiazole monomers and oligomers. The longitudinal component, αxx, is the largest of three principle components. On the other hand, the out-of-plane component, αzz, is the smallest. Moreover, the out-of-plane component (αzz) of thiophene, furan, pyrrole, (1,2,4)-triazole, (1,3,4)-oxadiazole, and (1,3,4)-thiadiazole monomers show constant changes with increasing optical frequencies. The frequency-dependent first- order polarizabilities increase in the order: thiophene > (1,2,4)-triazole > pyrrole > furan > (1,3,4)-thiadiazole > (1,3,4)-oxa-diazole monomers and oligomers. The effects of β(-2ω;ω,ω) (SHG) shows a larger dispersion compared with (-ω;ω,0) (EOPE) and β(0;-ω,ω) (OR). The second- order polarizabilities of thiophene, furan, pyrrole, (1,2,4)-triazole, (1,3,4)-thiadiazole, and (1,3,4)-oxadiazole monomers for the various second- order effects have the order: β(-2ω;ω,ω) (SHG) > β(-ω;ω,0) (EOPE) > β(0;-ω,ω) (OR) and thiophene > pyrrole > (1,2,4)-triazole > furan > 1,3,4-thiadiazole > 1,3,4-oxadiazole monomers. The third- order polarizabilities for the various third- order effects have the following order: γ(-3ω;ω',ω,ω) (THG) > γ(-2ω;0,ω,ω) (EFISHG) > γ(-ω;ω',-ω,ω) (IDRI) > γ(-ω;0,0,ω) (OKE). The effects of THG increase rapidly with increasing optical frequencies compared with the other effects. In particular, OKE effects increase most slowly with increasing optical frequencies. Also, the effects of THG for thiophene, furan, pyrrole, (1,2,4)-triazole, (1,3,4)-thiadiazole, and (1,3,4)-oxadiazole oligomers show the order thiophene > (1,2,4)-triazole > furan > pyrrole > (1,3,4)-thiadiazole > (1,3,4)-oxadiazole oligomers. In particular, the third- order polarizabilities of thiophene and (1,3,4)-thiadiazole oligomers are about four and three times larger than those of (1,3,4)-oxadiazole and (1,2,4)-triazole oligomer, respectively.

• Archives of Pharmacal Research
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• v.10 no.1
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• pp.14-17
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• 1987

Several new imidazo [1, 2-b] pyrazole, pyrazolo [5, 1-c]-1, 2, 4-triazine and pyrazolo [5, 1-c] triazole derivatives were prepared from the reaction of 3-antipyrinyl-5-aminopyrazole or its diazonium salt with .alpha.-chloroacetyl derivatives.

• Journal of the Korean Chemical Society
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• v.33 no.4
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• pp.419-425
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• 1989

Various 1-methyl-1,2,4-triazinium iodides were easily synthesized by the reaction of various 1,2,4-triazines and methyl iodide in acetone. When methyl iodide salts of 1,2,4-triazine derivatives were treated with $K_3Fd(CN)_6$ in 10% NaOH solution, 1-methyl-1,2,4-triazole derivatives as the main products were obtained by ring contraction. In addition to 1-methyl-1,2,4-triazole derivatives, 1,6-dihydro-6-oxo-1,2,4-triazine derivatives as the minor products were also obtained when there were no substitutents in $C_6$-position of 1,2,4-triazines. The formation of pseudo base by $OH^-$ and then oxidation to either 1,6-dihydro-6-oxo-1,2,4-triazines or 1-methyl-1,2,4-triazoles were suggested as the mechanism of the ring contraction. This mechanism also verified that the position of quaternization was neither $N_2$ nor $N_4$ but 1-nitrogen of 1,2,4-triazine.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.70-70
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• 1997

$\beta$-Lactamase 억제제로 6-Substituted exomethylene기를 갖는 penam계 화합물이 강력한 활성을 보여주고 있어서, $\beta$-lactamase억제제의 중간체 합성으로 6-exomethylene기에 도입 할 1-substituted thioalkyl-1,2,3-triazole-4-carboxaldehyde를 합성하였다. 2-Bromoethanol에 NaN$_3$를 반응시켜서 2-Azidoethanol을 합성하였고, 이것을 propargyl aldehyde와 반응시켜서 1-(2-hydroxyethyl)-1,2,3-triazole-4-carboxaldehyde를 합성하였다. 이것을 trifluoromethanesulfonic anhydride와 triethylamine존재 하에 heterocyclic mercapto화합물과 반응시켜서 hetorocyclic ring을 함유한 1-substituted thioalkyl-1,2,3-triazole-4-carboxaldehyde를 합성하였다.

• Bulletin of the Korean Chemical Society
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• v.11 no.5
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• pp.383-386
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• 1990

We have synthesized several bicyclic heteroaromatic compounds with bridgehead nitrogen from N-amine salts of heteroaromatic amines. 2-Amino and 2-unsubstituted thiazolo[3,2-b][l,2,4]triazole derivatives 2a-b were prepared by the cyclization reaction from N-amine salts of aminothiazole-5-yl(N-methoxyimino)acetate with cyanogen bromide and formamidine acetic acid salt, respectively. 2-Methylthiazolo[3,2-b][1,2,4]triazole 2c was obtained from N-acetylated N-amine salt of aminothiazole-5-yl(N-methoxyimino)acetate by the cyclization reaction in the presence of polyphosphoric acid (PPA). 2-Substituted and 2-unsubstituted thiazole[3,2-b][1,2,4]triazole derivatives 2a-c were coupled with 7-aminocephalosporanic acid (7-ACA). Coupled cephalosporin derivatives 1a-c did not have good antibacterial activities in vitro.

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.731-736
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• 2010

Several new 5-aryl-3-($\beta$-D-glucopyranosylthio)-1,2,4-triazoles have been synthesized. The structures of these new compounds were confirmed by $^1H$ NMR, $^{13}C$ NMR and elemental analyses.The antibacterial activities of the compounds were also evaluated.

• Journal of the Korean Chemical Society
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• v.11 no.3
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• pp.85-88
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• 1967

The main object of this experiment is to provide a systematic approach to the reaction mechanism in the photolysis of 5-phenyl-1,2,3,4-tetrazole during which the formation of C-phenyl-nitrile-imine of 1.3-dipole was expected. So the occurrence of 1,3-dipole-addition was examined but not observed despite the formation of nitrile-imine. 3,6-diphenyl-1,2,4,5-tetrazine (IV); 3,6-diphenyl-1,4-dihydro-1,2,4,5-tetrazine (III); 3,5-diphenyl-1,2,4-triazole; 4-amino-3,5-diphenyl-1,2,4-triazole; benzonitrile; ammonia and nitrogen were isolated as final products of this reaction.

• Journal of the Korean Applied Science and Technology
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• v.23 no.4
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• pp.355-361
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• 2006

[1,2,4]-Triazole derivatives were synthesized by 5 steps. Benzimidazole was refluxed with ethyl chloroacetate to give 1H-benzimidazole-acetic acid ethyl ester (1) over 52% yield. Ester (1) was refluxed with hydrazine hydrate in the presence of ethanol to afford 1H-benzimidazole-1-acetic acid, hydrazide (2). 5-Benzoimidazol-1-ylmethyl-4H-[1,2,4]triazole-3-thiol (4) was made via coupling of compound (2) with methyl isothiocyanate, followed by cyclization of 1H-benzimidazole-1-acetic acid, 2-[(methylamino) thioxomethyl]hydrazide (3) on reflux, and finally the target compounds (6a-6v) were synthesized by general substitution reaction. Compounds (6a-6v) were screened for T-type calcium channel blocker using the fluorescence assay by FDSS6000. All compounds (6a-6v) did not show better activities than control compound, mibefradil.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1080-1085
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• 2006

A series of 8-alkoxy-4,5-dihydro-[1,2,4]triazole[4,3-a]quinoline-1-one derivatives were synthesized using 7-hydroxy-3,4-dihydro-2(1H)-quinolone as the starting material. Their anticonvulsant activities were evaluated by the maximal electroshock test (MES) and the subcutaneous pentylenetetrazole test (sc-PTZ), and their neurotoxicities were measured by the rotarod neurotoxicity test (Tox). The tests demonstrated that 8-hexyloxy-4,5-dihydro-[1.2.4]triazole[4.3-a]quinoline-1-one (4e) and 8-heptyloxy-4,5-dihydro-[1,2,4]triazole[4, 3-a]quinoline-1-one (4f) were the most potent anticonvulsants, with 4e having $ED_{50}$ values of 17.17 mg/kg and 24.55 mg/kg and protective index ($PI=TD_{50}/ED_{50}$) values of 41.9 and 29.3 in the MES and sc-PTZ tests, respectively, and 4f having $ED_{50}$ values of 19.7 mg/kg and 21.2 mg/kg and PI values of 36.5 and 33.9 in the MES and sc-PTZ tests, respectively. The PI values of 4e and 4f were many fold better than that of the marketed drugs phenytoin, carbamazepine, phenobarbital and valproate, which have PI values in the range of 1.6-8.1 in the MES test and <0.22-5.2 in the sc-PTZ test. Structure-activity relationships were also discussed.

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1617-1620
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• 2008