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], C(13)H(13)IN(2)O(5), 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...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.