title: Janus-type AT nucleosides: synthesis, solid and solution state structures.
abstract: Novel Janus-type nucleoside analogues (1a-d) were synthesized. Their pyrimido[4,5-d]pyrimidine base moiety has one face with a bidentate Watson-Crick donor-acceptor (DA) H-bond array of adenine and the other face with an acceptor-donor (AD) H-bond array of thymine. These nucleosides may self-associate through the self-complementary base pair. Indeed, in the solid state, compound 6d displayed a honeycomb-like supramolecular structure with tetrameric membered cavities formed through the combination of reverse Watson-Crick base pairs and aromatic stacking, in which the solvent molecules were accommodated. The result of temperature-dependent CD studies showed that the free nucleosides can form higher order chiral structures in aqueous solution.
authors.affiliation: Institute for Nanobiomedical Technology and Membrane Biology, Regenerative Medicine Research Center, West China Hospital, West China Medical School, Sichuan University, Chengu, China.
authors.forename: Mei-Ying
authors.initials: MY
authors.lastname: Pan
authors.forename: Wen
authors.initials: W
authors.lastname: Hang
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Zhao
authors.forename: Hang
authors.initials: H
authors.lastname: Zhao
authors.forename: Peng-Chi
authors.initials: PC
authors.lastname: Deng
authors.forename: Zhi-Hua
authors.initials: ZH
authors.lastname: Xing
authors.forename: Yong
authors.initials: Y
authors.lastname: Qing
authors.forename: Yang
authors.initials: Y
authors.lastname: He
mesh_terms: D000225:Adenine / Q000138:chemical synthesis / Q000737:chemistry*; D020029:Base Pairing; D002942:Circular Dichroism; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D009705:Nucleosides / Q000138:chemical synthesis / Q000737:chemistry*; D013941:Thymine / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D009705:Nucleosides; D000225:Adenine; D013941:Thymine