Collect. Czech. Chem. Commun. 1989, 54, 1336-1345

Synthesis and spectral properties of pyrrolo[3',4':5,6]-4H-pyrano[2,3-d]pyrimidine derivatives

Štefan Marchalína, Františka Pavlíkováb and Dušan Ilavskýa

a Department of Organic Technology, Slovak Technical University, 812 37 Bratislava
b Central Laboratory of NMR Spectroscopy, Prague Institute of Chemical Technology, 166 28 Prague 6


The starting 2-amino-5-ethoxycarbonyl-6-chloromethyl-4-(2-furyl)-3-cyano-4H-pyran (I) afforded on condensation with triethoxymethane 2-ethoxymethylenamino-4H-pyran II; treatment of the latter with ammonia yielded 2-formamidino-3-cyano-4H-pyran III, which, when heated in dilute ethanol, cyclized to 4-amino-6-ethoxycarbonyl-5-(2-furyl)-7-chloromethyl-4H-pyrano[2,3-d]pyrimidine (IV). Compound IV reacted with alkyl- or arylamines to give substituted 5H,6H,8H-pyrrolo[3',4':5,6]-4H-pyrano[2,3-d]pyrimidines VI, one of which (VIb, R = p-CH3C6H4) was alternatively obtained from 2-formamidino-4H-pyrano derivative III. The structures of new tricyclic heterocycles were corroborated by analysis of the NMR spectral data.