Synthesis of 4,6-diamino-5-(polyhydroxyalkylamido)pyrimidines: conformation of the sugar chain
作者:Derek Horton、Oscar Varela
DOI:10.1016/s0008-6215(98)00078-0
日期:1998.3
Condensation of 4,5,6-triaminopyrimidine with ethyl glycolate, D-ribono-1,4-lactone, D-allono-1,4-lactone, D-glucono-1,5-lactone, and L-gulono-1,4-lactone led to the corresponding 4,6-diamino-5-(hydroxyalkylamido)pyrimidines (1a-e). The conformations in acidic aqueous solution of these acyclic carbohydrate derivatives were determined from the proton-proton NMR coupling constants at 300 MHz. The polyhydroxyalkyl chain of compounds 1b-e adopt sickle conformations in order to avoid the 1,3-parallel interactions between hydroxyl groups present in the planar zigzag conformer. Cyclization of 4,6-diamino-5-(hydroxyacetamido)pyrimidine (1a) afforded 8-(hydroxymethyl)adenine (2a), which was acetylated to give 2f. The C-13 NMR spectra of compounds 1a-e and 2a and f are also reported. (C) 1998 Elsevier Science Ltd. All rights reserved.