The H-1 and C-13 NMR resonances of four 3H-naphtho[2,1-b]pyrans were comple
tely and unambiguously assigned by a combination of homonuclear (gs-COSY),
H-1-detected heteronuclear one-bond (gs-HMQC) and long-range (gs-HMBC) grad
ient-selected correlation experiments. Copyright (C) 1999 John Wiley & Sons
, Ltd.