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001-es BibID:	BIBFORM009001
Első szerző:	Kurtán Tibor (vegyész, angol szakfordító)
Cím:	Chiral recognition by CD-sensitive dimeric zinc porphyrin host. 2. Structural studies of host-guest complexes with chrial alcohol and monoamine conjugates / Tibor Kurtán, Nasri Nesnas, Frank E. Koehn, Yuan-Qiang Li, Koji Nakanishi, Nina Berova
Dátum:	2001
Megjegyzések:	A structural study of complexes formed between a dimeric zinc porphyrin tweezer (host) and chiral monoalcohols and monoamines derivatized by a bidentate carrier molecule (guest) confirmed that their CD couplets arise from the preferred porphyrin helicity of 1:1 host-guest complexes. NMR experiments and molecular modeling of selected tweezer complexes revealed that the preferred conformation is the one in which the L (larger) group protrudes from the porphyrin sandwich; this preferred helicity of the complex determines the CD of the complexes. It was found that the porphyrin ring-current induced 1H chemical shifts and molecular modeling studies of the complex lead to the assignments of relative steric size of the L (large)/M (medium) substituents attached to the stereogenic center. The assignments, in turn, are correlated with the sign of the CD exciton couplet that establishes the absolute configuration at the stereogenic center. Variabletemperature NMR experiments proved that the observed increase in CD amplitude at lower temperatures derives from conformational changes in the preferred offset geometry between two porphyrin rings.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Journal of American Chemical Society. - 123 : 25 (2001), p. 5974-5982. -
További szerzők:	Nesnas, Nasri Koehn, Frank E. Li, Yuan-Qiang Nakanishi, Koji Berova, Nina
Internet cím:	elektronikus változat
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