Crystal and molecular structure of 5-[1-(2′-deoxy-α-d-ribofuranosyl)uracilyl] disulfide

The molecular structure of 5-[1-(2′-deoxy-α-d-ribofuranosyl) uracilyl] disulfide (I) has been determined by X-ray crystallographic analysis. The molecule crystallizes in the orthorhombic space group P212121, with the following cell dimensions: a = 9.492 Å., b = 14.061 Å., c = 16.328 Å. The valence state about the S-S linkage appears to be markedly different from that observed in other disulfide structures. The torsional angle about this bond is 49° and the S-S bond length was found to be 2.108 å. The configurations of both the uracil and the deoxyribosyl residues are different in the two nucleoside units of the molecule. The crystal is bound together by hydrogen bonds.