%0 Journal Article %1 Polak:2003:Nucleic-Acids-Res:12682357 %A Polak, M %A Manoharan, M %A Inamati, G B %A Plavec, J %D 2003 %J Nucleic Acids Res %K conformation nmr nucleotide %N 8 %P 2066-2076 %T Tuning of conformational preorganization in model 2',5'- and 3',5'-linked oligonucleotides by 3'- and 2'-O-methoxyethyl modification %U http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=153733 %V 31 %X Conformational properties of trimeric and tetrameric 2',5'-linked oligonucleotides, 3'-MOE-A3(2',5') (1) and 3'-MOE-A4(2',5') (2), and their 3',5'-linked analogs, 2'-MOE-A3(3',5') (3) and 2'-MOE-A4(3',5') (4), were examined with the use of heteronuclear NMR spectroscopy. The temperature-dependent 3JHH, 3JHP and 3JCP coupling constants, acquired in the range of 273-343 K, gave insight into the conformation of sugar rings in terms of a two-state North South (N S) pseudorotational equilibrium and into the conformation of the sugar-phosphate backbone in the model antisense oligonucleotides 1-4. 2',5'-linked oligomers 3'-MOE-A3(2',5') (1) and 3'-MOE-A4(2',5') (2) show preference for N-type conformers and indication of A-type conformational features, which is prerequisite for antisense hybridization. The drive of N S equilibrium in 1-4 has been rationalized with the competing gauche effects of 2'/3'-phosphodiester and 3'/2'-MOE groups, anomeric and steric effects. Furthermore, the pairwise comparisons of 3'-MOE with 3'-OH and 3'-deoxy 2',5'-linked adenine trimers emphasized the fine tuning of N S equilibrium in 3'-MOE-A3(2',5') (1) and 3'-MOE-A4(2',5') (2) by the steric effects of 3'-MOE group and the possibility of water-mediated H-bonds with vicinal phosphodiester functionality. In full correspondence, the drive of N S equilibrium towards N by 2'-MOE in 3',5'-linked analogs 2'-MOE-A3(3',5') (3) and 2'-MOE-A4(3',5') (4) is weaker in comparison with 3'-OH group in the corresponding ribo analogs. Beta(t), gamma+ and epsilon- rotamers are preferred in both 2',5'- and in 3',5'-linked oligonucleotides 1-4.

@article{Polak:2003:Nucleic-Acids-Res:12682357, abstract = {Conformational properties of trimeric and tetrameric 2',5'-linked oligonucleotides, 3'-MOE-A3(2',5') (1) and 3'-MOE-A4(2',5') (2), and their 3',5'-linked analogs, 2'-MOE-A3(3',5') (3) and 2'-MOE-A4(3',5') (4), were examined with the use of heteronuclear NMR spectroscopy. The temperature-dependent 3JHH, 3JHP and 3JCP coupling constants, acquired in the range of 273-343 K, gave insight into the conformation of sugar rings in terms of a two-state North South (N S) pseudorotational equilibrium and into the conformation of the sugar-phosphate backbone in the model antisense oligonucleotides 1-4. 2',5'-linked oligomers 3'-MOE-A3(2',5') (1) and 3'-MOE-A4(2',5') (2) show preference for N-type conformers and indication of A-type conformational features, which is prerequisite for antisense hybridization. The drive of N S equilibrium in 1-4 has been rationalized with the competing gauche effects of 2'/3'-phosphodiester and 3'/2'-MOE groups, anomeric and steric effects. Furthermore, the pairwise comparisons of 3'-MOE with 3'-OH and 3'-deoxy 2',5'-linked adenine trimers emphasized the fine tuning of N S equilibrium in 3'-MOE-A3(2',5') (1) and 3'-MOE-A4(2',5') (2) by the steric effects of 3'-MOE group and the possibility of water-mediated H-bonds with vicinal phosphodiester functionality. In full correspondence, the drive of N S equilibrium towards N by 2'-MOE in 3',5'-linked analogs 2'-MOE-A3(3',5') (3) and 2'-MOE-A4(3',5') (4) is weaker in comparison with 3'-OH group in the corresponding ribo analogs. Beta(t), gamma+ and epsilon- rotamers are preferred in both 2',5'- and in 3',5'-linked oligonucleotides 1-4.}, added-at = {2008-03-18T11:10:26.000+0100}, author = {Polak, M and Manoharan, M and Inamati, G B and Plavec, J}, biburl = {https://www.bibsonomy.org/bibtex/2ea7f5bdee35c34fde237be0212e488fa/rstenutz}, description = {Tuning of conformational preorganization in model 2′,5′- and 3′,5′-linked oligonucleotides by 3′- and 2′-O-methoxyethyl modification}, interhash = {847ae759a8e68c94eeeb7062775b6fc1}, intrahash = {ea7f5bdee35c34fde237be0212e488fa}, journal = {Nucleic Acids Res}, keywords = {conformation nmr nucleotide}, month = Apr, number = 8, pages = {2066-2076}, pmid = {12682357}, timestamp = {2008-03-18T11:10:27.000+0100}, title = {Tuning of conformational preorganization in model 2',5'- and 3',5'-linked oligonucleotides by 3'- and 2'-O-methoxyethyl modification}, url = {http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=153733}, volume = 31, year = 2003 }