Complete assignment of the H-1 and C-13 NMR spectra of 2-phenyl-3H-naphtho[2,1-b][1,4]oxazin-3-one, 2-p-methoxyphenylnaphtho[1,2-d]oxazole and 2-phenylnaphtho[1,2-d]oxazole. Concerted use of one- and two-dimensional NMR techniques