Crystal structure of 5,6-dihydro-1-methyl-4-thiouracil

Abstract

The X-ray crystal structure of the title compound was solved by the heavy-atom method from diffractometer data and refined by least-squares methods to R 0·107 for 1476 reflections. The crystals are monoclinic, space-group P2₁/c, Z= 8, with a= 8·086, b= 19·57, c= 8·864 Å, and β= 100·53°. The two independent molecules in the asymmetric unit both have the ketothione form, and a half-chair conformation. They are linked by two hydrogen-bonds between N(3) and O(2), the molecules being twisted at 33° to one another.