Long-range coupling constants (5)J(Hortho,OMe) were measured in series of methoxyindoles, methoxycoumarins, and methoxyflavones by the modified J doubling in the frequency domain method. The COSY and NOESY spectra revealed the coupling of the -OMe group with a specific proton at the ortho position and its preferred conformation. Homonuclear H-1-H-1 couplings were confirmed by irradiation of the -OMe signal. Density functional theory calculations of (5)J(Hortho,OMe) using the modified aug-cc-pVTZ basis set evidenced that the Fermi contact term shows good agreement with the experimental J values. Accurate chemical shift and coupling constant values followed after iterative quantum mechanical spectral analysis using the PERCH software. Copyright (C) 2014 John Wiley & Sons, Ltd.