[The structure and antiviral activity of ribavirin analogs. III. Molecular and crystal structure of 1-(2-hydroxyethoxymethyl)-1,2,4-triazole-carboxamide]. / Struktura i protivovirusnaia aktivnost' analogov ribavirina. III. Molekuliarnaia i kristallicheskaia struktura 1-(2-gidroksiétoksimetil)-1,2,4-triazol-3-karboksamida.

The crystal and molecular structure of a ribavirin acyclic analogue, 1-(2-hydroxyethoxymethyl)-1,2,4-triazole-3-carboxamide, has been determined by X-ray diffraction method. The space group is P1, unit cell parameters: a = 5,237, b = 6,960, c = 11,483 A, alpha = 93,89, beta = 97,43, gamma = 94,26 degrees; Z = 2. The structure was solved by the direct method and refined by least-squares procedure to R = 3.7%. Two molecular conformers statistically coexist in the unit cell, differing in the hydroxyethoxymethyl group conformation. Trans-conformation about O4'-C4' bond and gauche about C4'-C5' bond are observed in both molecules. C1'-O4' bond is approximately perpendicular to the aglicon.

[The structure and antiviral activity of ribavirin analogs. II. Molecular and crystal structure of 1-(1,5-dihydroxy-3-oxapent-2-yl)-1,2,4-triazole-5-carboxamide]. / Struktura i protivovirusnaia aktivnost' analogov ribavirina. II. Molekuliarnaia i kristallicheskaia struktura 1-(1,5-digidroksi-3-oksapent-2-il)-1,2,4-triazol-5-karboksamida.

X-ray structure of the title compound, an antiviral agent moderately active towards Herpes simplex virus type 1, has been determined. The space group is P2i/n, unit cell parameters: a = 10,119, b = 7,529, c = 13,585 A, beta = 107,82 degrees, Z = 4. The structure was solved by the direct method and refined by least-squares procedure to R = 2.9%. The gauche-conformation about C4'-C5' bond and trans-conformation about O4'-C4' bond are realized in the molecule. The carboxyamide group at the C5 atom of triazol cycle provides a steric opportunity for the intramolecular hydrogen bond C1'-H1'...O6 formation.