Rainer Soyka, W. Pfleiderer, R. Prewo
Jun 20, 1990
Citations
0
Influential Citations
33
Citations
Journal
Helvetica Chimica Acta
Abstract
Pteridines: Synthesis and Characteristics of 5,6-Dihydro-6-(1,2,3-trihydroxypropyl)pteridines: Covalent Intramolecular Adducts Various 5,6-diaminopyrimidines (1, 15, 24, 33) were condensed with the phenylhydrazones of L-(2) and D-arabinose (3) in acidic medium under N2 to give formal 5,6-dihydro-6-(1,2,3-trihydroxypropyl)pteridines (see, e.g., 4 and 5), the latter turned out to exist preferentially as intramolecular adducts, the hexahydropyrano-[3,2-g]pteridines 6, 7, 16, 17, 25, 26, and 34, formed subsequently by addition of the terminal OH group of the side-chain to the C(7)N(8) bond of the pteridine moiety. Spectroscopically, the isomeric hexahydrofuro-[3,2-g]pteridines 10,11,18,19, and 35 were also detected as minor components in the equilibrium mixtures. In the 4-amino-2-(methylthio)pteridine series, crystallization of 6 and 7 led to the stereochemically pure (3S,4R,4aR, 10aS)-6-amino-3,4,4a,5,10,10a-hexahydro-8-(methylthio)-2H-pyrano[3,2-g]pteridine-3,4-diol (8) and its corresponding enantiomer 9, respectively Structure 8 was proven by X-ray analysis. Acylation of the hexahydropyrano[3,2-g]pteridines yielded the more stable tri-, tetra-, and pentaacetyl derivatives 12–14, 20–23, 27–32, and 37–39 which were characterized and of which the absolute and relative configurations were determined (1H- and 13C–NMR and UV spectra, chiroptical measurements, elemental analyses).