Preparation of 3(5)-phenyl-1-hydroxypyrazole 2-oxide and 4-methyl-3(5)-phenyl-1-hydroxypyrazole 2-oxide

Nitrosation of acrylophenone oxime or of methacrylophenone oxime with n-butyl nitrite in the presence of pyridine and copper(II) sulfate gives the copper complexes of the title compounds. The free 1-hydroxypyrazole 2 -oxides are isolated by treating the copper complexes with dilute sodium hydroxide, filtration, and acidification of the basic filtrates. The title compounds are the first examples of 1-hydroxypyrazole 2 -oxides in which the C3(5) ring position is unsubstituted.     

Synthesis of 1-(2,4,6-trichlorophenyl)-2-(1,2,4-triazol-4-yl)-diazene-1-oxide

By reaction of 4-amino-1,2,4-triazole with 1-nitroso-2,4,6-trichlorobenzene in the presence of excess dibromoisocyanurate the title compound was obtained.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 362–364, February, 1992.     

Synthesis of 4-(2-acetoxyethoxymethyl)-6-methyl-1,2,4-triazin-3(4H)-one 1-oxide as thymidine analogue

Alkylation of the sodium salt and the trimethyl silylated derivatives of 6-methyl-1,2,4-triazin-3(4H)-one 1-oxide with chloromethoxyethyl acetate, n-hexyl chloride and benzyl bromide gave the 4-substituted products. However, attempts to achieve the ring closure of N⁴-(2-acetoxyethoxymethyl)thiosemicarbazide with bicarbonyl compounds to the corresponding as-triazines under different reaction conditions was not possible without disruption of the acetoxyethoxymethyl moiety. Although the as-triazine nucleoside analog II did not show antileukemic activity, this and other 4-alkylated as-triazine 1-oxides revealed good growth inhibitory effects against a representative spectrum of microorganisms.     

Synthesis and reactions of a monosubstituted dithiirane 1-oxide, 3-(9-triptycyl)dithiirane 1-oxide

A 3-monosubstituted dithiirane 1-oxide, 3-(9-triptycyl)dithiirane 1-oxide, was prepared for the first time, by the reaction of (9-triptycyl)diazomethane and S₈O. The dithiirane 1-oxide was obtained as cis- and trans-isomers, and the structure of the trans-isomer was verified by X-ray crystallography. The cis-isomer isomerized gradually to the trans-isomer in solution. The divalent sulfur atom of the cis- and trans-dithiirane 1-oxides were removed on treatment with triphenylphosphine to give the corresponding Z- and E-sulfines, respectively. The reaction of the trans-dithiirane 1-oxide with (Ph₃P)₂Pt(C₂H₄) provided the (sulfenato-thiolato)Pt^II complex, and that with Lawesson's reagent yielded the 1,3,4,2-trithiaphospholane and 1,2,4,5,3-tetrathiaphosphorinane derivatives.     

2,3-二甲基-4-(2,2,2-三氟乙氧基)吡啶-1-氧化物的合成

以2,3-二甲基-4-硝基吡啶-1-氧化物为原料,合成兰索拉唑中间体2,3-二甲基-4-(2,2,2-三氟乙氧基)吡啶-1-氧化物（2）,其结构经¹H NMR确证。研究了溶剂、催化剂、碱和反应时间等因素对2收率的影响。结果表明：在最优反应条件(乙腈作溶剂,三氟乙醇2.0 eq.,碳酸钾2.5 eq.,在1 mol%TBAB水溶液中反应10 h)下,2收率超过85%。将实验规模放大到100 g级,工艺稳定。     

Alkylation of tetrazoles with 3-(2-bromoethyl)-1-methoxy-3-methyltriaz-1-ene 2-oxide

Alkylation of tetrazoles with 3-(2-bromoethyl)-1-methoxy-3-methyltriaz-1-ene 2-oxide proceeded at positions 1 and 2 of the tetrazole ring to give a mixture of two isomers.

     

2-(3’,5’-二硝基苯)-4-硝基-1,2,3-三唑-1-氧化物的合成与量子化学研究

以乙二醛、苯肼和盐酸羟胺为起始原料,经缩合和肟化反应制得肟基苯腙(1)。在硫酸铜-吡啶-水体系中,1经缩合环化得2-苯基-1,2,3-三唑-1-氧化物(2);2被混酸硝化合成了新化合物2-(3’,5’-二硝基苯)-4-硝基-1,2,3-三唑-1-氧化物(3),纯度99%,总收率45%,其结构经1H NMR,IR,MS和元素分析表征。在B3LYP/aug-cc-pVDZ基组水平上对3的结构进行了优化,获得稳定的几何构型。