title: 5-Amino-1-(2',3'-O-iso-propyl-idene-d-ribit-yl)-1H-imidazole-4-carboxamide: a crystal structure withZ' = 4.
abstract: The title compound, C12H20N4O5, crystallizes in the monoclinic space groupP21, with four crystallographically independent mol-ecules in the asymmetric unit. The four mol-ecules have a very similar conformation that is basically determined by the formation of two intra-molecular hydrogen bonds between the amino NH2donors and the carbonyl and ring O-atom acceptors, forming, respectively,R(6) andR(7) ring motifs.. In the crystal, inter-molecular hydrogen bonding leads to the formation ofR22(10) ring patterns, involving one amide CONH2donor and an imidazole N-atom acceptor. The cluster of the four independent mol-ecules has approximate non-crystallographicC2point symmetry. The structural analysis also shows that during the synthesis of the title compound, the reductive cleavage of the d-ribose ring of the inosine precursor proceeds stereoselectively, with retention of configuration.
authors.affiliation: Dipartimento di Scienze Chimiche, Università degli Studi di Napoli 'Federico II', Complesso di Monte S. Angelo, Via Cinthia, 80126 Napoli, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Piccialli
authors.affiliation: Dipartimento di Farmacia, Università degli Studi di Napoli 'Federico II', Via D. Montesano 49, 80131 Napoli, Italy.
authors.forename: Nicola
authors.identifier: https://orcid.org/0000-0003-0216-9814
authors.initials: N
authors.lastname: Borbone
authors.affiliation: Dipartimento di Farmacia, Università degli Studi di Napoli 'Federico II', Via D. Montesano 49, 80131 Napoli, Italy.
authors.forename: Giorgia
authors.initials: G
authors.lastname: Oliviero
authors.affiliation: Dipartimento di Farmacia, Università degli Studi di Napoli 'Federico II', Via D. Montesano 49, 80131 Napoli, Italy.
authors.forename: Gennaro
authors.initials: G
authors.lastname: Piccialli
authors.affiliation: Dipartimento di Farmacia, Università degli Studi di Napoli 'Federico II', Via D. Montesano 49, 80131 Napoli, Italy.
authors.forename: Stefano
authors.identifier: https://orcid.org/0000-0002-8100-3726
authors.initials: S
authors.lastname: D'Errico
authors.affiliation: Dipartimento di Scienze Chimiche, Università degli Studi di Napoli 'Federico II', Complesso di Monte S. Angelo, Via Cinthia, 80126 Napoli, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Centore
keywords: crystal structure; high Z′ structures; hydrogen bonding; nucleosides