CRYSTAL AND MOLECULAR-STRUCTURE OF (+)-CARBA-THYMIDINE, C11H16N2O6

The molecular structure of (+)-carta-thymidine possessing notable anti-HSV activity has been determined by single crystal X-ray diffraction. It crystallizes in the monoclinic space group P2 with unit cell dimensions a = 4.310(2), b = 11.560(1)1, c = 10.014(1) A, β= 92.34(2)°, Z = 2. The structure was solved by direct methods and refined by least squares to a final R = 0.038 for 1027 reflections (I > 3σ(I)). The torsion angle x around the glycosidic N1-C1' bond agrees with that of thymidine (37.5o vs 39.1) whereas the C3' -exo pucker of the five—membered ring is shifted to an even less common Cl'-exo form. © 1990, Taylor & Francis Group, LLC. All rights reserved.