The N-1-(2 `-deoxyribofuranoside) of 3-iodo-5-nitroindole: a universal nucleoside forming nitro-iodo interactions

Abstract

The title compound [systematic name:1-(2-deoxy-beta-D-erythro-pentofuranosyl)-3-iodo-5-nitro-1H-indole] , C13H13IN2O5, exhibits an anti glycosylic bond conformation with a chi torsion angle of -114.9 (3)degrees. The furanose moiety shows a twisted C2'-endo sugar pucker (S-type), with P = 141.3 degrees and tau(m) = 40.3 degrees. The orientation of the exocyclic C4'-C5' bond is ap (gauche, trans), with a gamma torsion angle of 177.4 (2)degrees. The extended crystal structure is stabilized by hydrogen bonding and I center dot center dot center dot O contacts, as well as by stacking interactions. The O atoms of the nitro group act as acceptors, forming bifurcated hydrogen bonds within the ac plane. Additionally, the iodo substituent forms an interplanar contact with an O atom of the nitro group, and another contact with the O atom of the 5 `-hydroxy group of the sugar moiety within the ac plane is observed. These contacts can be considered as the structure-determining factors for the molecular packing in the crystal structure.