Macrocycles cyclam

B = a tetraamido macrocycle, cyclam-acetate = l,4,8,ll-tetramethyl-l,4,8,ll-tetraaza-cyclo-... 

Stability of Complexes of the Porphyrin TSPP Compared with the Nitrogen Donor Macrocycles Cyclam and THEC, with Metal Ions of Biological Interest"... 

Some examples of the complexes discussed in this chapter are shown in Pig. 1. The active site , i.e., partially reduced oxygen, appears as an end-on superoxo, hydroperoxo, or oxo group. Other ligands are mostly water, ammonia, N4-macrocycles (cyclam and Me6-cyclam, abbreviated as L1 and L2, respectively), and N202 -chelates, typically salen. These ligands are chemically inert under most of the circumstances,... 

According to the modular approach, components of the fluorosensor can be changed at will. For instance, it could be of some interest to replace the quad-ridentate receptors of systems 4 and 5 by their cyclic counterparts, to obtain 6 and 7 [8]. The reason of the interest is that, ceteris paribus, cyclic ligands form more stable metal complexes than their open-chain analogues (the thermodynamic macrocyclic effect [12]). The tetramine receptor in 6 has the skeleton of the classical 14-membered macrocycle cyclam, whereas the receptor subunit of 7 refers to the other well-known object of macrocyclic chemistry dioxocyclam. 

TABLE 10.11. PERAZA-14-CROWN-4 MACROCYCLES (CYCLAM) (UNSUBSTITUTED NITROGEN ATOMS)... 

Ch. 9 Aza-Crown Macrocycles Containing Other Heteroatoms in the Macroring Ch. 10 Aliphatic Peraza-Crown Macrocycles (Cyclams)... 

The reflection-absorption IR spectra RAIRS of the macrocycles cyclam and cyclamdione and their copper complexes onto a smooth copper surface were pub-lished It has been concluded that the orientation of the cyclam molecules is plane parallel to the surface with the interaction being directed by the nittogen lone pair electrons. Figure 14.24 contains the IR and RAIR spectra of cyclamdione and its Cu(ll) complex. 

Diaz, G., R.E. Clavijo, M.M. Campos-VaUette, M. Saavedra, S. Diez, L. Lopez, and R. Munoz (1997). Specular reflectance infrared spectra of the macrocycles cyclam and cyclamdione and their Cu(II) complexes deposited onto a smooth copper surface. Vib. Spectrosc. 15, 201. 

As a new series of "open-chain cryptands", "multi-armed cyclams" were designed and employed in the cation transport experiments. Parent polyamine macrocycle (cyclam) is well known to show somewhat different cation binding properties from those of macrocyclic polyethers. It effectively bind ammoniiim cations via strong hydrogen bonding as well as transition metal cations via coordination interaction. Hence, new "multi-armed cyclams" are expected to exhibit unique cation transport abilities. Their cation transport results are summarized in Table 3. 

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