NMR and molecular modelling based conformational analysis of some N-alkyl 1- and 2-benzazepinones: Useful central nervous system agent design motifs

Variable temperature IK NMR lineshape analyses and C-13 NMR spin-lattice relaxation time studies were undertaken to characterise the conformationally dynamic N-alkyl 1- and 2-benzazepinones 1 and 2. For 1, dynamic interchange between two minor-image puckered forms of the azepine ring occurs with a barrier of 56 kJ mol(-1). There is a significantly greater degree of ring flexibility in the case of 2. Molecular modelling studies were used to examine the degree of sidechain flexibility in these compounds. (C) 1994 Academic Press, Inc