title: 2'-Methylseleno-modified oligoribonucleotides for X-ray crystallography synthesized by the ACE RNA solid-phase approach.
abstract: Site-specifically modified 2'-methylseleno RNA represents a valuable derivative for phasing of X-ray crystallographic data. Several successful applications in three-dimensional structure determination of nucleic acids, such as the Diels-Alder ribozyme, have relied on this modification. Here, we introduce synthetic routes to 2'-methylseleno phosphoramidite building blocks of all four standard nucleosides, adenosine, cytidine, guanosine and uridine, that are tailored for 2'-O-bis(acetoxyethoxy)methyl (ACE) RNA solid-phase synthesis. We additionally report on their incorporation into oligoribonucleotides including deprotection and purification. The methodological expansion of 2'-methylseleno labeling via ACE RNA chemistry is a major step to make Se-RNA generally accessible and to receive broad dissemination of the Se-approach for crystallographic studies on RNA. Thus far, preparation of 2'-methylseleno-modified oligoribonucleotides has been restricted to the 2'-O-[(triisopropylsilyl)oxy]methyl (TOM) and 2'-O-tert-butyldimethylsilyl (TBDMS) RNA synthesis methods.
authors: Institute of Organic Chemistry, Center for Molecular Biosciences Innsbruck (CMBI), Leopold Franzens University, Innrain 52a, 6020 Innsbruck, Austria.
authors: Barbara
authors: B
authors: Puffer
authors: Holger
authors: H
authors: Moroder
authors: Michaela
authors: M
authors: Aigner
authors: Ronald
authors: R
authors: Micura
mesh_terms: D000249:Adenosine Monophosphate / Q000031:analogs & derivatives; D001671:Biochemistry / Q000379:methods; D018360:Crystallography, X-Ray; D003568:Cytidine Monophosphate / Q000031:analogs & derivatives; D006157:Guanosine Monophosphate / Q000031:analogs & derivatives; D009843:Oligoribonucleotides / Q000138:chemical synthesis* / Q000737:chemistry; D009943:Organophosphorus Compounds / Q000737:chemistry*; D016566:Organoselenium Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D012313:RNA / Q000138:chemical synthesis; D014542:Uridine Monophosphate / Q000031:analogs & derivatives
chemical_list: D009843:Oligoribonucleotides; D009943:Organophosphorus Compounds; D016566:Organoselenium Compounds; C434331:phosphoramidite; D000249:Adenosine Monophosphate; D012313:RNA; D006157:Guanosine Monophosphate; D014542:Uridine Monophosphate; D003568:Cytidine Monophosphate