is an example of a naphthoquinone imine in a specific tautomeric form. This structure is stabilized by a intramolecular H-bond between the N-H and the carbonyl and London attraction between the two tert-butyl groups.  The imine C=N bond length at C4 is 1.291 (2) Å , which is shorter than the enamine C—N bond length at C2  [1.353 (2) Å ], indicating that the tautomer shown is the correct structure in the solid state.

Chemical Context 

Naphthoquinones (naphthalenediones) form an important part of some pharmacophores in medicinal chemistry. During an exploration of antimalarial drugs, Fieser indicated that aminoiminonaphthoquinones (Fig. 1), although difficult to form, had interesting medicinal properties. Bullock et al. further investigated these compounds as antiprotozoal agents and provided more efficient ways to synthesize a series of these compounds.