Crystal Structure of the 1 : 1 Complex of 5-Fluorouracil and 9-Ethylhypoxanthine
Sung-Hou Kim 1 and
Alexander Rich 1
1 Department of Biology, Massachusetts Institute of Technology, Cambridge 02139
9-Ethylhypoxanthine and 5-fluorouracil form a 1 : 1 crystalline complex. The structure of this complex has been solved by x-ray diffraction analysis. The molecules crystallize in a monoclinic lattice and form a sheet structure in which pairs of fluorouracil molecules are held together by two hydrogen bonds. The 9-ethylhypoxanthine residues fill up the rest of the molecular sheet by forming single hydrogen bonds with each uracil pair.