The interaction of histidine, cysteine, NO and nitrite with cobalt(II) N,N',N″,N‴-tetramethyltetra-3,4-tetrapyridinoporphyrazine ([ Co II tmtppa ]4+) is reported. Metal-based autoreduction of [ Co II tmtppa ]4+ occurs with the formation of the [ Co I tmtppa (-2)]3+ species in the presence of histidine and cysteine. Kinetic data for the auto reduction of [ Co II tmtppa ]4+ in the presence of these amino acids gave the rate constants k f = 2.1 × 101 and 2.8 dm3 mol-1 s-1, for cysteine and histidine, respectively. One molecule of NO or nitrite was found to coordinate to the [ Co II tmtppa ]4+ species. The equilibrium and rate constants for the coordination of the nitric oxide were K = 2.3 × 104 dm 3 mol -1 and k f = 7.5 dm 3 mol -1 s -1, respectively. The coordination of nitrite to [ Co II tmtppa ]4+ occurred with an equilibrium constant of K = 2.0 × 102 dm 3 mol -1 and a rate constant of k f = 4.0 × 10-3 dm 3 mol -1 s -1. There was no evidence for the coordination of two molecules of nitrite to the [ Co II tmtppa ]4+ species.

中文翻译：

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钴(II) N,N',N",N‴-四甲基四-3,4-吡啶并卟啉与氨基酸和氮氧化物相互作用的光谱研究

组氨酸、半胱氨酸、NO 和亚硝酸盐与钴 (II) N,N',N",N‴-tetramethyltetra-3,4-tetrapyridinoporphyrazine ([ Co二tmtppa]4+) 被报告。[ Co 的金属基自动还原二tmtppa]4+随着 [ Co 的形成而发生一世tmtppa (-2)]3+存在组氨酸和半胱氨酸的物种。[ Co 的自动还原动力学数据二tmtppa]4+在这些氨基酸的存在下给出了速率常数 kF= 2.1 × 101和 2.8 分米3摩尔-1s-1，分别为半胱氨酸和组氨酸。发现一分子 NO 或亚硝酸盐与 [Co二tmtppa]4+物种。一氧化氮配位的平衡常数和速率常数为 K = 2.3 × 104分米3摩尔-1和 kF= 7.5 分米3摩尔-1s-1， 分别。亚硝酸盐与[ Co二tmtppa]4+发生平衡常数 K = 2.0 × 102分米3摩尔-1和 k 的速率常数F= 4.0 × 10-3分米3摩尔-1s-1. 没有证据表明两分子亚硝酸盐与[ Co二tmtppa]4+物种。