2’‐Derivatisation of 3’‐ C‐ Methyl Pyrimidine Nucleosides

Prebiotic Synthesis of Pyrimidine Nucleosides

Metabolism of pyrimidine L-nucleosides.

The intraperitoneal application of L-nucleosides (L-Cyd, L-Urd, L-dThd) to mice results in distribution of these compounds into tissues of the organism and their gradual excretion in the unchanged form. The residual level has been observed with L-ribonucleosides only and contains in addition to the L-nucleoside its 5'-phosphate. The phosphorylation in vivo is catalyzed by nucleoside-kinase and ...

5-Methyl-3-(3-methyl­phen­yl)-7-phenyl-1,2,4-triazolo[4,3-c]pyrimidine

The title compound, C(19)H(16)N(4), is one of the few known 3,7-diaryl-1,2,4-triazolo[4,3-c]pyrimidines. The triazolopyrimidine unit is essentially planar (r.m.s. deviation = 0.048 Å). The phenyl ring and the heterocyclic core subtend a dihedral angle of only 15.09 (6)°, whereas the m-tolyl ring is twisted by 71.80 (6)° out of the plane of the triazole ring. Two C-H⋯N hydrogen bonds and π-π sta...

4,6-Bis[5-methyl-3-(trifluoro­meth­yl)pyrazol-1-yl]pyrimidine

The complete mol-ecule of the the title compound, C(14)H(10)F(6)N(6), is generated by crystallographic twofold symmetry, with two C atoms lying on the roatation axis. The dihedral angle between the central and peripheral rings is 25.97 (8)°.

Pyrimidine acyclo-C-nucleosides by ring transformations of 2-formyl-L-arabinal.

The protected 2-formyl-L-arabinal 2 reacted with thiourea and cyanamide in the presence of sodium hydride to afford via ring transformations the 5-[1R,2S-1,2- bis(benzyloxy)-3-hydroxypropyl]-1,2-dihydropyrimidines 3 and 4, respectively. Similarly, treatment of 2 with 3-amino-2H-1,2,4-triazole yielded 6-[1R,2S-1,2- bis(benzyloxy)-3-hydroxypropyl][1,2,4]-triazolo[1,5-a]pyrimidine (5).