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001-es BibID:	BIBFORM072801
Első szerző:	Boros Sándor
Cím:	Accurate NMR determinations of proton-proton distances / Sándor Boros, Zoltán Gáspári, Gyula Batta
Dátum:	2018
ISSN:	0066-4103
Megjegyzések:	There are obvious reasons why precise internuclear distance measurements are essential in structural chemistry. Here we wish to give a practice-oriented review on the topic of accurate proton-proton distance measurements by solution NMR. The history of NOE and ROE methods is quite long, and the ambition has always been to tackle with the distance problem in a quantitative sense. The reader can find a basic introduction to relaxation and incoherent magnetization transfer by cross-relaxation. With the improvement of NMR instrument technology and improved measuring pulse sequences it has become everyday practice to run NOE/ROE experiments. Though the principles of quantitative NOE experiments have been known for decades, the full potential of the methods is rarely used for either small or big molecules. Here we suggest those improved experimental methods and their evaluation protocols that can be followed for accurate distance determination. Improvements in NOESY and ROESY sequences are presented, as well as the possibility of the "exact NOE" option for biopolymers. Hopefully, the interested reader can apply the techniques explained in this review.
ISBN:	978-0-12-815212-6
Tárgyszavak:	Természettudományok Kémiai tudományok könyvfejezet Relaxation NOE NOESY ROESY Interatomic distances
Megjelenés:	Annual Reports on NMR Spectroscopy / Ed. by Graham A. Webb. - p. 1-39. -
További szerzők:	Gáspári Zoltán Batta Gyula (1953-) (molekula-szerkezet kutató)
Pályázati támogatás:	OTKA-110821 OTKA GINOP-2.3.2-15-2016-00008 GINOP
Internet cím:	DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM068520
Első szerző:	Boros Sándor
Cím:	Offset-compensated and zero-quantum suppressed ROESY provides accurate 1H-1H distances in small to medium-sized molecules / Sándor Boros, Gyula Batta
Dátum:	2016
ISSN:	0749-1581
Megjegyzések:	A robust version of the off-resonance ROESY pulse scheme is suggested for the measurement of proton?proton distances or slow chemical exchange in small to medium-sized molecules. The method implements adiabatic ramps to establish a pair of opposite frequency off-resonance spin lock fields - with optionally randomized duration - and adiabatic inversion pulses with simultaneous gradients for efficient zero-quantum suppression. The amended pulse sequence yields pure absorption cross-peaks and works safely for small to medium-sized molecules. The applicability of the method has been demonstrated using small, rigid molecules (strychnine and codeine) and was also applied for a cyclic peptide and a small protein. We found that the pure phase cross-peaks of the new ROESY version are beneficial for distance measurements. The one-dimensional (selective) version of the new method is also powerful for measuring selected pair-wise interactions and distance determination.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban NMR off-resonance ROESY zero-quantum suppression offset compensation
Megjelenés:	Magnetic Resonance in Chemistry 54 : 12 (2016), p. 947-952. -
További szerzők:	Batta Gyula (1953-) (molekula-szerkezet kutató)
Pályázati támogatás:	ANN-110821 OTKA
Internet cím:	DOI Intézményi repozitóriumban (DEA) tárolt változat
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