Abstract A novel class of fused azaisocytosine-containing congeners, i.e. 3-(4-nitrophenyl)-8-(R-phenyl)-7,8-dihydroimidazo[2,1-c][1,2,4]triazin-4(6H)-ones, acting as anticancer antimetabolites, were subjected to the heating in order to evaluate their decomposition mechanism. The pyrolysis and oxidative decomposition course was studied with a use of simultaneous thermal analysis: thermogravimetry/differential scanning calorimetry (TG/DTG/DSC) coupled online with Fourier transform infrared spectroscopy (FTIR) and Quadrupole mass spectrometry (QMS). The performed analyses allowed to conclude that, the pyrolysis and oxidation processes of the tested compounds run through simultaneous, radical processes in one, main stage (inert conditions) or in two stages (oxidative conditions) resulting in the emission of NH3, RNCO, HCN, CO, CO2, NO2, aromatics and alkenes (inert atmosphere) and NH3, RNCO, HCN, CO, CO2, NO2, NO, N2O, H2O, aromatics and alkenes (oxidative atmosphere). The results confirmed the simultaneous breaking of C C, C N, N H, C H and C Cl bonds in the starting compounds and the created intermediates, and then additional oxidation processes of some, formed products to the corresponding nitrogen oxides and water. The connection between the thermal behaviour of the tested compounds and their possible use as candidates for pharmaceutical applications was emphasized.

中文翻译：

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带对硝基苯基的退火三嗪酮的分解机理

摘要 一类新的含氮杂异胞嘧啶的稠合同源物，即 3-(4-nitrophenyl)-8-(R-phenyl)-7,8-dihydroimidazo[2,1-c][1,2,4]triazin-4 (6H)-ones，作为抗癌抗代谢物，被加热以评估它们的分解机制。使用同步热分析研究热解和氧化分解过程：热重/差示扫描量热法 (TG/DTG/DSC) 与傅里叶变换红外光谱 (FTIR) 和四极杆质谱 (QMS) 在线耦合。所进行的分析得出的结论是，测试化合物的热解和氧化过程在一个主要阶段（惰性条件）或两个阶段（氧化条件）中同时进行自由基过程，导致 NH3、RNCO、HCN 的排放, CO, CO2, NO2, 芳烃和烯烃（惰性气氛）和 NH3、RNCO、HCN、CO、CO2、NO2、NO、N2O、H2O、芳烃和烯烃（氧化气氛）。结果证实，起始化合物和产生的中间体中的 CC、CN、NH、CH 和 CCl 键同时断裂，然后一些额外的氧化过程将形成的产物转化为相应的氮氧化物和水。强调了测试化合物的热行为与其作为药物应用候选物的可能用途之间的联系。生成的产物为相应的氮氧化物和水。强调了测试化合物的热行为与其作为药物应用候选物的可能用途之间的联系。生成的产物为相应的氮氧化物和水。强调了测试化合物的热行为与其作为药物应用候选物的可能用途之间的联系。