1.2.3- Triazole 4-methyl-5-nitro-2-

In aryl- or amino-substituted 1,2,4-triazols the nitro group enters the side chain [269-271], An attempt to realize the nitration of 3,5-bisphenylamino-l,2,4-triazole led to opening of the triazole ring. Picrylurea was isolated as the only reaction product [272], The nitration products of 2-methyl-l,2,3-triazole 1-oxide under mild conditions (20°C) are a mixture of 5-nitro (75%) and 4-nitro (23%) derivatives. Under more... 

Influence of pH medium on the UV-absorption spectra of 5-nitro-l,2,4-triazole, 3-methyl-5-nitro-l,2,4-triazole, 4-nitro-2-(l,2,4-triazole-3-yl)-l,2,3-triazole and nitroderivatives of l,2,4-triazolone-5 [611, 613,1180] has been considered. 

Formyl-hydrazino)-3-methoxy-E9a. 663 (NH2 -> NH-CHO) 6-Methyl-3-(methyl-nitro-amino)-E9a, 653 (NH -+N-N02) lH-l,2,4-Triazol 1-Acetyl-3-acetyla-mino- E8d, 562 (N,N-Bis-acetylier.)... 

Several approaches to the 1,2,3-triazole core have been published in 2000. Iodobenzene diacetate-mediated oxidation of hydrazones 152 led to fused 1,2,3-triazoloheterocycles 153 <00SC417>. Treatment of oxazolone 154 with iso-pentyl nitrite in the presence of acetic acid gave 1,2,3-triazole 155, a precursor to 3-(W-l,2,3-triazolyl)-substituted a,P-unsaturated a amino acid derivatives <00SC2863>. Aroyl-substituted ketene aminals 156 reacted with aryl azides to provide polysubstituted 1,23-triazoles 157 <00HC387>. 2-Aryl-2T/,4/f-imidazo[43-d][l,2,3]triazoles 159 were prepared from the reaction of triethyl AM-ethyl-2-methyl-4-nitro-l//-imidazol-5-yl phosphoramidate (158) with aryl isocyanates <00TL9889>. 

Ring opening of also a fused [l,2,4]triazole system by secondary amines has been reported. Chupakhin et al. described that 5-methyl-6-nitro[l,2,4]triazolo[l,5-r ]pyrimidin-7(8/f)one 122 underwent ring opening when treated with various secondary amines to yield pyrimidyl ureas 123 in medium to good yield <2001IZV655>, as shown in Scheme 14. 

Methyl 3,3-diazido-2-cyanoacrylate, 1824 Methylenebis(3 -nitramino-4-methylfurazan), 2805 1-Methyl-1,2,3-triazole, 1189 Nitrosyl azide, 4766 3-Nitro-l,2,4-triazolone, 0716 Pentazole, 4443... 

Amino-5-nitro-1,2,3-triazole (ANTZ) (130), an explosive showing high thermal stability, has been synthesized via this route the reaction of sodium azide, acetaldehyde and 2,2-dinitroethyl acetate forming 4-methyl-5-nitro-1,2,3-triazole, which on conversion of the methyl group to an amino group yields ANTZ (130). Treatment of ANTZ (130) with hydrogen peroxide in sulfuric acid yields 4,5-dinitro-1,2,3-triazole (DNTZ) (131). 

Methoxy-l,2,3,4-thiatriazole, 0773 1-Methyl-l,2,3-triazole, 1189 4-Nitroamino-1,2,4-triazole, 0777 4-Nitro-l-picryl-l,2,3-triazole, 2886 3-Nitro-l,2,4-triazolone, 0716 1-Picryl-l,2,3-triazole, 2893... 

The starting material for the synthesis of the 4-substituted derivatives 176 was the tautomeric 4(7)-nitrobenzo-triazole 173, which upon methylation with dimethyl sulfate in aq NaOH afforded the 4-nitro-2-methylbenzotriazole 174. The H NMR spectrum of the purified reaction mtKture after methylation showed the existence of all three triazole ring iV-methylated isomers in equal amounts. Compound 174 was isolated by virtue of its insolubility in cone HCl. Purity of products was confirmed by gas liquid chromatography (GLC). 

Vilsmeier reaction, 4, 1051 Furo[3,2-6]pyrroles MO calculations, 6, 979 synthesis, 4, 1069 6, 1009 Furo[3,4-a]pyrrolo[2,1,5-cd]indolizine nomenclature, 1, 22 Furopyrylium salts, 4, 993-995 Furoquinolines biosynthesis, 4, 992 occurrence, 4, 988 pharmacology, 4, 992 reactions, 4, 988 synthesis, 4, 989 Furo[3,2-c]quinolines, 4, 991 Furo[3,4-fe]quinoxaline, 1,3-diphenyl-synthesis, 4, 993 Furoquinoxalines, 4, 992 Furo[2,3-6]quinoxalines synthesis, 4, 992 Furosemide toxicity, 1, 136 Furospinulosin UV spectra, 4, 587 Furospongin-I mass spectrometry, 4, 583 Furo[3,4-d][l,2,3]triazole, 2,6-dihydro-synthesis, 6, 996 Furo[3,4 -d][ 1,2,3]triazoles synthesis, 6, 996 Furoxan, 4-amino-3-aryl-tautomerism, 6, 404 Furoxan, 4-amino-3-methyl-synthesis, 4, 414 Furoxan, 4-aryl-3-methyl-rearrangement, 6, 408 Furoxan, 3-aryl-4-nitro-synthesis, 6, 414 Furoxan, 4-benzoyl-3-methyl-oxime... 

C8H3N708 mw 325.18 N 30.16% OB to C02 -46.74% cryst mp 233° (explds) d 1.85g/cc sol in hot methyl ethyl ketone Prepn. A soln of 8.12g of picryl fluoride, 4.00g of 4-nitro-lH-l, 2,3-triazole, and 100ml of dry DMF is stirred at room temp under a dry atm for 24 hrs. The soln is poured with stirring into l of w. The crude product is collected by filtration, washed thoroughly with several portions of w, and dried. This product is then dissolved in a minimal amt of hot methyl ethyl ketone. The soln Is chilled, and the material that crystd is collected by filtration and washed with cold eth to give 3.28g of product. The vol of the mother liquor is reduced until crystn is induced, and a second product crop of 1.97g is isolated. The total yield is 5.25g (46%)... 

Nitration of 2-methyl-l,2/3-triazole 341 (R=Me) proceeded smoothly furnishing a mixture of 4- and 5-nitro derivatives 362 (R=Me) and 363 (R=Me). Both transformed to the 4,5-dinitro compound 364 (R=Me) at elevated temperature (1986ACSA(B)262). 

Nitro-l,2,4-triazole (45%) [451] and l-methyl-4-cyano-5-nitropyrazole (42%) [452] were isolated during the oxidation of corresponding aminoazole derivatives by a solution of hydrogen peroxide in trifluoroacetic acid. One of the amino groups in l-acyl-3,5-diamino-l,2,4-triazole is oxidized by hydrogen peroxide in the presence of sodium tungstate [453] (Scheme 59). 

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