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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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21 71 N-Cbz-leucinate 4.23
71 N-Cbz-norleucinate 4.85
23 71 N-/ prolinate 0.00
24 71 N-Cb/.-methionate 5.64
25 71 N-Cbz-serinate 2.94
26 71 N-Cb/-phenylglycinate 5.63
27 71 N-(3.5-dinitrobenzoyl)- 7.74
phenylglycinate
28 71 N-Cbz-phenylalaninate 4.04
29 71 N-C'b/-tryptophanate 5.09
30 71 polylgliitamie acid) 4.18
31 70 histidine methyl ester 6.4
32 70 histidine benzyl ester 54
33 70 lysine ben/.yl ester 2.5
34 72 oetyl a-glucopyranoside 3.1
Solvent Temperature (K) Method Reference
CHCh 288 UV-Vis 18
CHCI 288 UV-Vis 18
CHCI, 288 UV-Vis 18
CHCI, 288 UV-Vis 18
CHCI < 288 UV-Vis 18
CHCI, 288 UV-Vis 18
CHCI, 288 UV-Vis 18
CHCI, 288 UV-Vis 18
CHCI, 288 UV-Vis 18
CH,CN 293 UV-Vis 81
CH.Ch 293 UV-Vis 81
CH-.CN 293 UV-Vis 81
ch-.cn 293 UV-Vis 81
CHiCN 293 UV-Vis 81
CHCI,/water l-.t. extraction 64
CHCI, /water r.t. extraction 64
CHCh/water r.t. extraction 64
CHCh/water r.l. extraction 64
CHCh/water r.t. extraction 64
CHCh/water r.t. extraction 64
CHCh/water r.t. extraction 64
CHCh/water r.t. extraction 64
CHCI i/water r.t. extraction 64
C'HCl,/water r.t. extraction 64
CHCI,/water r.t. extraction 64
CHCh/water r.t. extraction 64
CHCh/water r.t. extraction 64
CHCh/water r.t. extraction 64
CHCh/water r.t. extraction 64
Me0H-H,0 (3/1.v/v) 293 UV-Vis 65
CDC1, 'H NMR 59
toluene 293 'H NMR 59
toluene 293 'H NMR 59
CH.Ch 295 UV-Vis 83
300
Ogoshi et al.
phase from water by the chiral strapped N-methyl zinc porphyrin 71.64 Due
to the /V-methyl group, the zinc complex has a positive charge, and
acetate is coordinated to the zinc as an axial ligand. The host can
extract sodium salts of N-protected amino acids from water by ligand
exchange. In the complex between N-protected amino acids and host, three
interactions are responsible for chiral discrimination: a coordinating
interaction between a metal atom (Zn) and a carboxylate anion, a
hydrogen-bonding interaction between the amide group of porphyrin and
that of the guest, and a steric interaction between the guest and a rigid
wall of strap. iV-Benzyloxycarbonyl-DL-valinate was extracted by host 71
with an enantiomeric excess of 84%. Similarly, N-(3,5-
dinitrobenzoyl)phenylglycinate was extracted with 92% enantiomeric
excess.
The same porphyrin 71 was found to recognize the helical sense of
poly(glutamic acid).65 Poly(L-glutamic acid) assumes a right-handed a-
helical conformation in aqueous methanol or acetonitrile over a pH range
of 3-8. (5)-71 was enantioselectively bound to poly(L-glutamic acid) via
a ligand-exchange reaction between the original acetate of 71 and the
carboxylate groups of poly(glutamic acid). The association constant for
(5)-71 was 3 x 103 M -1 while that for (R) was 5.1 x 102M"_I, and the
chiral recognition free energy amounts to AAGql =4.18kJ/mol.
Crossley et al. reported a dimer porphyrin 70 which is able to
recognize chirality of amino acids.59 In CDCI3 the host recognizes
histidine methyl ester with an enantiomeric excess of 86% (AAGql = 6.4 kJ
/ mol). The host can also recognize the chirality of lysine benzyl ester
with the chiral recognition free energy (AAGqJ of 2.5 kJ/mol at 20 C in
toluene. Considering the flexibility of lysine methyl ester, this
enantioselectivity is quite high. 'H NMR studies indicated that the
conformation of the bound guest was restricted owing to the ditopic
binding.
Bonar-Law reported chiral recognition of amino-acid esters by steroid-
capped zinc porphyrin receptor 72 in 2 and in SDS micelle.82 It
showed enantioselective binding of 6.3kJ/mol for serine in CD2C12 and of
8.2 kJ / mol for threonine (the difference in the association free
energy) at 295 in a SDS micellar solution. Bonar-Law and Sanders
reported an enantioselective binding (AAG = 3.1 kJ/mol) of octyl
glucopyranoside by steroid-capped zinc porphyrin 72.83
E. ALCOHOLS AND SUGAR RECOGNITION
Use of porphyrin-based receptors for sugar recognition provides some
advantages because the sensitive probing ability of porphyrins greatly
helps in the detection of interaction with carbohydrates, which are, in
general, spectroscopically poor substrates.
Bonar-Law and Sanders reported the alcohol and carbohydrate
recognition by steroid-capped zinc porphyrin 72 in chloroform and several
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