The results of geometry optimisation of possible Watson-Crick-like pairs of 2,6-diamino-4-oxy-5-formamidopyrimidine (fapy-adenine) or 4,6-diamino-5-formamidopyrimidine (fapy-guanine) were presented. In the absence of the external field the fapy-adenine is able to form pairs with all four canonical nucleic acid bases. However, pairs with guanine, cytosine and thymine the most stable are. Thus, t...

In the title compound, [Fe(CH(3)CN)(3)(C(29)H(27)N(5)OP(2))](BF(4))(2)·2CH(3)CN, the Fe(II) ion is octa-hedrally coordinated by a meridionally chelating tridentate pincer-type PNP ligand derived from 2,6-diamino-4-eth-oxy-1,3,5-triazine and by three acetonitrile mol-ecules. The four Fe-N bond lengths range from 1.9142 (12) to 1.9579 (11) Å, while the Fe-P bonds are 2.2452 (4) and 2.2506 (4) Å [...

In this study, three methods are utilized to analyze toxicity produced by methotrexate and the lipid-soluble antifolate, 2,4-diamino-5-(3',4'-dichlorophenyl)-6-methylpyrimidine, in human lymphoblasts (WIL-2) and leukemic cells. These methods detect increasingly severe metabolic damage; inhibition of deoxyuridine incorporation into DNA, the reversibility of inhibition of deoxyuridine incorporati...

In the title salt, C(5)H(8)N(3) (+)·C(7)H(4)NO(4) (-), the pyridine N atom of the 2,3-diamino-pyridine mol-ecule is protonated. The protonated N atom and one of the two 2-amino groups are hydrogen bonded to the 4-nitro-benzoate anion through a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. The carboxyl-ate mean plane of the 4-nitro-benzoate anion is twisted by 3.77 (5)° from t...