Structure of 1-tert-Butyl-3-hydroxymethyl-3-nitroazetidine and 1-Bromoacetyl-3,3-dinitroazetidine, an Investigative Anticancer Agent Derived from Energetic Materials

Abstract

The structures of a novel investigative anticancer agent 1-bromoacetyl-3,3-dinitro azetidine (ABDNAZ, 2) and its synthetic precursor 1-tert-butyl-3-hydroxymethyl-3-nitroazetidine (1) were determined by single crystal X-ray diffraction. The data show that the chemical transformation from 1 to 2 resulted in an increase in crystal density of 0.725 Mg/m3 (1 = 1.232 Mg/m3; 2 = 1.957 Mg/m3). The azetidine ring of 1 is puckered while 2 is planar, consistent with sp2 hybridization of the ring nitrogen following conversion of the tertiary amine to an amide. The structural information will aid in elucidating the biological activity of 2. Single crystal X-ray diffraction studies revealed that conversion of 1-tert-butyl-3-hydroxymethyl-3-nitroazetidine to 1-bromoacetyl-3,3-dinitroazetidine results inflattening of the azetidine ring due to sp2 hybridization of the ring nitrogen, and a crystal density increase of 0.725 Mg/m3 (1.232 vs. 1.957 Mg/m3 respectively) is observed.