Synthesis and structural study of N-substituted nortropane spirohydantoins

A series of N8-alkyloxycarbonylalkyl-nortropane-3-spiro-5'-hydantoins has been synthesized and studied by spectral and crystallographic methods. The crystal and molecular structure of one [8(gamma-ethoxycarbonyl)nortropane-3-spiro-5'-hydantoin, VI] was determined by X-ray diffraction. The preferred conformations of these compounds and subsequent changes on protonation were determined from 1H-NMR and 13C-NMR data.