novel 4 - substituted cyclohexanes substituted in the 1 - position with 2 - benzimidazoles , 2 - imidazopyridines , or 4 - imidazoles either directly or through a c 1 - c 4 alkyl , cycloalkyl , hydroxyalkyl , alkoxy or aminoalkyl chain are effective as nmda nr2b antagonists useful for relieving pain .