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-DIMENSIONAL AND 2-DIMENSIONAL NMR TECHNIQUES

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 were totally assigned using a combination of one-and two-dim ensional NMR techniques. In addition to correlation of the proton sign als by a COSY spectrum and one-bond heteronuclear correlation, complet e assignment of the H-1 and C-13 NMR spectra of these heterocyclic com pounds required the application of long-range CH coupling information, particularly for quaternary resonance assignments and for orientation s of individual spin systems relative to one another. (C) 1998 John Wi ley & Sons, Ltd.