A prebiotically plausible synthesis of pyrimidine β-ribonucleosides and their phosphate derivatives involving photoanomerization.
Previous research has identified ribose aminooxazoline as a potential intermediate in the prebiotic synthesis of the pyrimidine nucleotides with remarkable properties. It crystallizes spontaneously from reaction mixtures, with an enhanced enantiomeric excess if initially enantioenriched, which suggests that reservoirs of this compound might have accumulated on the early Earth in an optically pure form. Ribose aminooxazoline can be converted efficiently into α-ribocytidine by way of 2,2'-anhydroribocytidine, although anomerization to β-ribocytidine by ultraviolet irradiation is extremely inefficient. Our previous work demonstrated the synthesis of pyrimidine β-ribonucleotides, but at the cost of ignoring ribose aminooxazoline, using arabinose aminooxazoline instead. Here we describe a long-sought route through ribose aminooxazoline to the pyrimidine β-ribonucleosides and their phosphate derivatives that involves an extraordinarily efficient photoanomerization of α-2-thioribocytidine. In addition to the canonical nucleosides, our synthesis accesses β-2-thioribouridine, a modified nucleoside found in transfer RNA that enables both faster and more-accurate nucleic acid template-copying chemistry.
MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.
Jianfeng
J
Xu
MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.
Maria
M
Tsanakopoulou
MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.
Christopher J
0000-0001-5757-9832
CJ
Magnani
Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 61265 Brno, Czech Republic.
Rafał
R
Szabla
Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 61265 Brno, Czech Republic.|CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, CZ-62500 Brno, Czech Republic.
Judit E
JE
Šponer
Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 61265 Brno, Czech Republic.|CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, CZ-62500 Brno, Czech Republic.
Jiří
J
Šponer
Department of Physical and Quantum Chemistry, Faculty of Chemistry, Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
Robert W
0000-0003-0253-4295
RW
Góra
MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.
John D
JD
Sutherland
D019418:Evolution, Chemical; D008968:Molecular Conformation; D010080:Oxazoles / Q000737:chemistry*; D010710:Phosphates / Q000138:chemical synthesis* / Q000737:chemistry; D055668:Photochemical Processes; D011743:Pyrimidines / Q000138:chemical synthesis* / Q000737:chemistry; D012263:Ribonucleosides / Q000138:chemical synthesis* / Q000737:chemistry*; D012266:Ribose / Q000737:chemistry*
D010080:Oxazoles; D010710:Phosphates; D011743:Pyrimidines; D012263:Ribonucleosides; D012266:Ribose; C030986:pyrimidine