title: Synthesis of selenium-derivatized nucleosides and oligonucleotides for X-ray crystallography.
abstract: We report here the synthesis of nucleoside and oligonucleotide analogs containing selenium, which serves as an anomalous scattering center to enable MAD phase determination in nucleotide X-ray crystallography. We have developed a phase transfer approach to introduce the selenium functionality in A, C, G, T, and U nucleosides at 5'-positions. In the incorporation of the selenium functionality, the leaving groups (bromide, mesyl, and tosyl) were readily displaced by sodium selenide, sodium diselenide, and sodium methyl selenide with yields higher than 90%. Selenium-derivatized oligonucleotides have been synthesized via phosphoramidite chemistry.
authors.affiliation: Department of Chemistry, Brooklyn College, The Graduate School of The City University of New York, 11210, USA.
authors.forename: N
authors.initials: N
authors.lastname: Carrasco
authors.forename: D
authors.initials: D
authors.lastname: Ginsburg
authors.forename: Q
authors.initials: Q
authors.lastname: Du
authors.forename: Z
authors.initials: Z
authors.lastname: Huang
mesh_terms: D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D009705:Nucleosides / Q000138:chemical synthesis* / Q000737:chemistry*; D009841:Oligonucleotides / Q000138:chemical synthesis* / Q000737:chemistry*; D018036:Selenium Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D009705:Nucleosides; D009841:Oligonucleotides; D018036:Selenium Compounds