Reactive nitrogen oxygen species（RNOS） implicate damage in biological systems,especially leading to inflammation,neurodegenerative and cardiovascular diseases,and cancer by altering the functions of biomolecules thr...Reactive nitrogen oxygen species（RNOS） implicate damage in biological systems,especially leading to inflammation,neurodegenerative and cardiovascular diseases,and cancer by altering the functions of biomolecules through the N-nitrosation and N-nitration reactions.The mechanisms of N-nitrosation and N-nitration reactions of ammonia and dimethylamine by RNOS,i.e.,N2O3,N2O4,N2O5 and ONOOH,were investigated at the CBS-QB3 level of theory.The computational results indicate that the N-nitrosation reaction prefers a concerted mechanism,in which a H-abstraction and ON-addition occur simultaneously,whereas a stepwise mechanism（also called a free radical mechanism） is more favorable for most nitrating agents in the N-nitration reaction,where NO2 first abstracts a hydrogen atom from the nitrogen of amines and then the induced intermediate reacts with NO2 once more to form the nitration products.However,the concerted pathway is still a feasible process for some nitrating agents such as N2O5.In addition,the relationship between the structures of different RNOS and their nitrosating or nitrating abilities was also investigated.展开更多
Two novel energetic compounds, 3,4-bis（1＇,2＇,4＇-triazole-3＇-yl）furoxan （BTAF） and 3,4-bis（1＇-nitro-l＇,2＇,4＇-tri- azole-3＇-yl）furoxan （BNTAF）, were prepared and their structures were characterized by I...Two novel energetic compounds, 3,4-bis（1＇,2＇,4＇-triazole-3＇-yl）furoxan （BTAF） and 3,4-bis（1＇-nitro-l＇,2＇,4＇-tri- azole-3＇-yl）furoxan （BNTAF）, were prepared and their structures were characterized by IR, ^1H NMR, ^13C NMR, MS techniques and elemental analysis. The properties of BTAF and BNTAF were estimated. The predicted per- formance data of BTAF are as follows： density （measured） is 1.75 g/cm3, nitrogen content 50.9%, detonation veloc- ity 7277 m/s, detonation pressure 20.1 GPa and enthalpy of formation ＋419.7 kJ/mol. The predicted performance data of BNTAF are as follows： density is 1.84 g/cm3, nitrogen content 45.2%, enthalpy of formation ＋841.5 kJ/mol, detonation velocity 8490 rn/s and detonation pressure 32.4 GPa. The main themal properties of BTAF and BNTAF were analyzed by DSC and TG techniques, the results show that BTAF melts with concomitant decompo- sition at 188.8℃, the melting point of BNTAF is at 99.2 ℃ and its first decomposition temperature is 139.2 ℃.展开更多
基金supported by the National Natural Science Foundation of China (No 20672011)Beijing Natural Science Foundation (No 2092008)Beijing Nova Program (No 2008B09)
文摘Reactive nitrogen oxygen species（RNOS） implicate damage in biological systems,especially leading to inflammation,neurodegenerative and cardiovascular diseases,and cancer by altering the functions of biomolecules through the N-nitrosation and N-nitration reactions.The mechanisms of N-nitrosation and N-nitration reactions of ammonia and dimethylamine by RNOS,i.e.,N2O3,N2O4,N2O5 and ONOOH,were investigated at the CBS-QB3 level of theory.The computational results indicate that the N-nitrosation reaction prefers a concerted mechanism,in which a H-abstraction and ON-addition occur simultaneously,whereas a stepwise mechanism（also called a free radical mechanism） is more favorable for most nitrating agents in the N-nitration reaction,where NO2 first abstracts a hydrogen atom from the nitrogen of amines and then the induced intermediate reacts with NO2 once more to form the nitration products.However,the concerted pathway is still a feasible process for some nitrating agents such as N2O5.In addition,the relationship between the structures of different RNOS and their nitrosating or nitrating abilities was also investigated.
文摘Two novel energetic compounds, 3,4-bis（1＇,2＇,4＇-triazole-3＇-yl）furoxan （BTAF） and 3,4-bis（1＇-nitro-l＇,2＇,4＇-tri- azole-3＇-yl）furoxan （BNTAF）, were prepared and their structures were characterized by IR, ^1H NMR, ^13C NMR, MS techniques and elemental analysis. The properties of BTAF and BNTAF were estimated. The predicted per- formance data of BTAF are as follows： density （measured） is 1.75 g/cm3, nitrogen content 50.9%, detonation veloc- ity 7277 m/s, detonation pressure 20.1 GPa and enthalpy of formation ＋419.7 kJ/mol. The predicted performance data of BNTAF are as follows： density is 1.84 g/cm3, nitrogen content 45.2%, enthalpy of formation ＋841.5 kJ/mol, detonation velocity 8490 rn/s and detonation pressure 32.4 GPa. The main themal properties of BTAF and BNTAF were analyzed by DSC and TG techniques, the results show that BTAF melts with concomitant decompo- sition at 188.8℃, the melting point of BNTAF is at 99.2 ℃ and its first decomposition temperature is 139.2 ℃.
