title: The interaction of a cobalt porphyrin with cancer-associated nitrosamines.
abstract: A cobalt porphyrin (CY-B) was presented, and its interaction with tobacco-specific nitrosamines (TSNAs) was investigated by UV-Vis spectroscopy and high-resolution mass spectrometry. The results revealed that the stoichiometry of the host-guest interaction was 1:2 and that the binding constant between CY-B and TSNAs was within the range of 0.78×10(8)-7.83×10(8)M(-2). The coordination strength between CY-B and TSNAs decreased in the sequence of NNN>NAB>NAT>NNK based on the binding constant. The interaction mechanism of CY-B with TSNAs involved a coordination interaction, and the π-π interaction between the porphyrin macrocycle and the aromatic frame of the TSNAs pyridines may also have been a driving force. The measured thermodynamic properties demonstrated that the reaction of CY-B with TSNAs was spontaneous and that the driving force for the interaction was a change in enthalpy. The reaction was exothermic, and an increasing temperature inhibited the interaction. The IR spectrum of the complex revealed that the NNO group of TSNAs and the metal cobalt of CY-B formed the six-coordinate complex.
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China; Harmful Components and Tar Reduction in Cigarette, Sichuan Key Laboratory Technical Research Center, Chuanyu Branch of China Tobacco Corporation, Chengdu 610066, China.
authors.forename: Feiyan
authors.initials: F
authors.lastname: Tao
authors.affiliation: Harmful Components and Tar Reduction in Cigarette, Sichuan Key Laboratory Technical Research Center, Chuanyu Branch of China Tobacco Corporation, Chengdu 610066, China. Electronic address: dycy@263.net.
authors.forename: Ya
authors.initials: Y
authors.lastname: Dai
authors.affiliation: Harmful Components and Tar Reduction in Cigarette, Sichuan Key Laboratory Technical Research Center, Chuanyu Branch of China Tobacco Corporation, Chengdu 610066, China.
authors.forename: Changguo
authors.initials: C
authors.lastname: Wang
authors.affiliation: Harmful Components and Tar Reduction in Cigarette, Sichuan Key Laboratory Technical Research Center, Chuanyu Branch of China Tobacco Corporation, Chengdu 610066, China.
authors.forename: Guanglin
authors.initials: G
authors.lastname: Feng
authors.affiliation: Harmful Components and Tar Reduction in Cigarette, Sichuan Key Laboratory Technical Research Center, Chuanyu Branch of China Tobacco Corporation, Chengdu 610066, China.
authors.forename: Dongliang
authors.initials: D
authors.lastname: Li
authors.affiliation: Harmful Components and Tar Reduction in Cigarette, Sichuan Key Laboratory Technical Research Center, Chuanyu Branch of China Tobacco Corporation, Chengdu 610066, China.
authors.forename: Kuoyan
authors.initials: K
authors.lastname: Ma
authors.affiliation: Harmful Components and Tar Reduction in Cigarette, Sichuan Key Laboratory Technical Research Center, Chuanyu Branch of China Tobacco Corporation, Chengdu 610066, China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Harmful Components and Tar Reduction in Cigarette, Sichuan Key Laboratory Technical Research Center, Chuanyu Branch of China Tobacco Corporation, Chengdu 610066, China.
authors.forename: Lanlan
authors.initials: L
authors.lastname: Tan
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China. Electronic address: xqyu@scu.edu.cn.
authors.forename: Xiaoqi
authors.initials: X
authors.lastname: Yu
mesh_terms: D003035:Cobalt / Q000737:chemistry*; D008665:Metalloporphyrins / Q000737:chemistry*; D015394:Molecular Structure; D009369:Neoplasms / Q000737:chemistry*; D009602:Nitrosamines / Q000737:chemistry*; D013816:Thermodynamics; D014026:Nicotiana / Q000737:chemistry*
chemical_list: D008665:Metalloporphyrins; D009602:Nitrosamines; D003035:Cobalt
keywords: Association constants; Cobalt porphyrin; Coordination interaction; Hemin; Metalloporphyrin; TSNAs