Macrocyclic polyamines

Dynamic anion recognition by macrocyclic polyamines in neutral pH aqueous solution 98CC1495. 

Macrocyclic Polyamines as Biological Cation and Anion Complexones — An Application to Calculi Dissolution... 

Application of Cation and Anion Binding Properties of Macrocyclic Polyamines... 

Interest in macrocyclic polyamines has been mostly limited to that shown by coordination chemists. 

Macrocyclic polyamines may be viewed as an extended form of linear polyamines 13-161 with one less degree of saturation. Polyamines with lower degrees of saturation, have important biological functions. Compounds such as macrocyclic polyimines 171 and porphyrines 18), function as 02 carriers and activators, promote photosynthesis, form the basic structure of vitamine B12, etc., and for these reasons have been subjects of intense investigation. 

The characteristic property distinguishing macrocyclic polyamines from their linear counterparts is seen in successive protonation. One is the higher N basicity to the first proton and another is a sudden drop of N basicities in the later stages of protonation. Table 1 lists the protonation constants (Eq. 1) for the macrocyclic polyamines in comparison with the corresponding values for their linear homologues. When a linear triamine (e.g. dien) 36,37) is cyclized to, say, (9)aneN3, the basicity of the first amine increases (log Kt = 10.59 us 9.70), but the basicity of the second and especially the third amine diminish (log K2 = 6.88 vs 8.95, log K3 < 1 vs 4.25)36)... 

Competition of Phosphate Anions and Metal Cations for Macrocyclic Polyamines... 

As seen in the preceding chapters, macrocyclic polyamines such as [18]aneN6 can be cation chelators, anion chelators, or both depending on the conditions. It was expected that with these dual properties, the macrocyclic polyamines might serve as litholytic agents by removing Ca2+ and phosphate or oxalate anions from insoluble calculi. 

Dissolution of Calculi Model. Dissolved Ions from Ca3(PCf)2. Dissolution of calcium phosphate by macrocyclic polyamines proceeds at pH 7, which is established by measuring the freed cation concentration as well as the freed anion concentration with respect to the control values (Table 7). The molar ratio of [Ca2 + ] to [P04 ]... 

Macrocyclic polyamines as biological cation and anion complexones — an application to calculi dissolution. E. Kimura, Top. Curr. Chem., 1985,128,113 (85). 

Fig. 32. Mononuclear Ni(II) and Zn(II) complexes of acyclic and macrocyclic polyamine-thiophenolate ligands (224).

Mode of Anti-HIV Action by Macrocyclic Polyamine Compounds. 156... 

While the basic and or applied chemistry of saturated macrocyclic polyamines, typically represented by 1,4,7,10-tetraazacyclododecane (cyclen, 1) and 1,4,8,11-tetraazacyclotetradecane (cyclam, 2), have both... 

Following these independent discoveries by the two groups, a number of macrocyclic polyamine derivatives have been assayed and synthesized... 

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