PMR spectra and structure of the open form of spironaphthooxazine

1.	The PMR spectra of the closed forms of spironaphthopyran and spironaphthooxazine were interpreted. The PMR spectra of the photoinduced forms of these compounds were obtained for the first time.
2.	The open form of spironaphthooxazine in nonpolar solvents was found to have the quinoid structure of one of the trans isomers, while there is a shift in the equilibrium toward the bipolar structure in polar solvents.

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1040–1046, May, 1989.