SYNTHESIS AND STRUCTURE DETERMINATION OF A NUCLEOSIDEDERIVED NEW HETEROCYCLIC SYSTEM: 8H,10H,15b(S)-2,3,6,7-TETRAHYDRO-1,5,3-DIOXAZEPINO[3,2-c]INDOLO[3,2-g]PTERIDINE-7-ONE

Abstract

Condensation of 5-aminocytidine with N-methylisatin yielded a new heterocyclic system, 8H,10H,15b(S)-2,3,6,7-tetrahydro-1,5,3-dioxazepino[3,2-c]indolo[3,2-g]pteridine-7- one. The assignment of S configuration at position 15b, which is generated as a result of the nucleophilic attack of the 5′-hydroxy of the ribosyl moiety at the position 6 of the cytosine base, is discussed.