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The porphyrin handbook - Kadish K.M.

Kadish K.M. The porphyrin handbook - Academic press, 2000. - 368 p.
Download (direct link): kadishsmishgulilard2000.djvu
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119 67 glutamic acid dimethyl ester 22.2 CHCh.
l%EtOH 298 UV-Vis 79
120 67 leucine methyl ester 24.2 CHCh
298 UV-Vis 79
121 67 aspartic acid dimethyl ester 27.6 CHC1,
298 UV-Vis 79
122 67 glutamic acid dimethyl ester 25.0 CHCh
298 UV-Vis 79
123 67 proline methyl ester 27.6 CHCh, 1
%EtOH 298 UV-Vis 79
124 67 cystein methyl ester 21.7 CHCh, 1
%EtOH 298 UV-Vis 79
125 67 methionine methyl ester 21.7 CHCh, 1
%EtOH 298 UV-Vis 79
126 68 leucine methyl ester 20.1 CHCh, 1%
298 UV-Vis 79
127 68 valine methyl ester 19.3 CHCh, 1%
298 UV-Vis 79
128 68 alanine methyl ester 17.3 CHCh, 1
%EtOH 298 UV-Vis 79
129 68 tryptophan methyl ester 20.6 CHCh, 1%
298 UV-Vis 79
130 68 aspariic acid dimethyl ester 17.0 CHCh, 1
%EtOH 298 UV-Vis 79
131 68 glutamic acid dimethyl ester 15.3 CHCh, 1%
298 UV-Vis 79
132 56 leucine methyl ester 21.6 CHCh, 1
%EtOH 298 UV-Vis 79
133 56 valine methyl ester 20.8 CHCh, 1%
298 UV-Vis 79
134 56 alanine methyl ester 18.1 CHCh, 1%
298 UV-Vis 79
135 56 tryptophan methyl ester 21.4 CHCh, 1%
298 UV-Vis 79
136 56 aspartic acid dimethyl ester 18.2 CHCh, 1%
298 UV-Vis 79
137 56 glutamic acid dimethyl ester 16.8 CHCh, 1%
298 UV-Vis 79
138 56 leucine methyl ester 23.5 CHCh
298 UV-Vis 79
46 / Porphyrins and
Metalloporphyrins as Receptor Models
Table 2. (continued)
Entry Host Guest - AC/kJ mol 1 Solvent
Temperature / (K) Method Reference
139 56 aspartic acid dimethyl ester 19.7 CHCI, 298
UV-Vis 79
140 56 glutamic acid dimethyl ester 19.3 CHCh 298
UV-Vis 79
141 f + )-70 L-histidine benzyl ester 46.3 toluene 293
'H NMR 59
142 (+)-70 i -lysine benzyl ester 41.4 toluene 293
'H NMR 59


50 n = 2
54 M = Rh(ll!)-CH2COCH3 56' M = Zn
55: M = Rh(l!l)-CH2COCH3

- enantiomer
)-59
58
cis, trans mixture
295
296
Ogoshi et al.
61 62
+ enantiomer
()-63
NO?
65
no2

66
OH
67
OH
OMe
68
OMe

L
46 / Porphyrins and Metalloporphyrins as Receptor Models
297
did not form a stable complex with free-base porphyrin
52 in water. Therefore, the binding of aromatic amino acids cannot be
ascribed to a simple hydrophobic interaction.
The complex formation between amino acids and [tetrakis(4-
melhylpyridinium)porphyrina(o]cobalt(llI) 27 was studied by 'H NMR
spectroscopy.1> Due to their slow dissociation rates on the NMR time
scale, detailed information on the conformation of bound guest was
obtained. Analysis of the complexation-induced shifts of the amino-acid
protons as well as comparison of coupling constants between C7 and C/(
and between NH and C7 protons revealed some interesting features of
amino-acid recognition in water. These are:
1. Among the polar functional groups of amino acids, the y-NH2 group is
coordinating to zinc, thus the driving force for the complexation is the
coordination interaction between the "-amino group and cobalt for most
cases.
2. For His, Lys, and Met, and at low' pH, coordination of (he polar side-
chain groups to cobalt occurred predominantly over the a-NH^
coordination. For instance, a coordination of the sulfur atom of
methionine to cobalt was observed at low pH (pH = 3.9), while at pH 9.8
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