X-ray diffraction

X-ray diffraction was used to determine the molecular structure of four different molecules. Attempts to crystallize the methanesulfonate salt of an antischistosomal drug, IA-4N-oxide, have led to an accidental preparation of yellowish thin-plate crystals which are monoclinic with space group C2/m and Z = 4. The results showed that the compound was the ammonium salt of methanesulfonic acid. A compound, C10H8N2S3, was crystallized from a solution of 1:1 mixture of toluene and chloroform at -16 degrees centigrade. In an attempt to prepare cadmium-UMP complex, Cd(NO3)2 was reacted with Na2(5'-UMP). The product obtained was [C5H6N+.Cd2Cl5-]/sub n/ which crystallizes with two basic formula species in an orthorhomibic unit cell of symmetry Pmnm. The analysis of crystals of 6,7-dihydro-3-methyl-2-one pyrimido[5,4-b][1,4]thiazine-7-carboxylic acid revealed that the molecule possesses a zwitterion structure and the molecular formula is C8H9N3S.xH7O, where x = 0.857 (8)