15N and 29Si NMR data of 2,5-hydro-1,2,5-azasilaborole derivatives and related compounds were determined with emphasis on coupling constants 1J(29Si 15N) which cannot be measured from 15N NMR spectra of most boron-nitrogen compounds. In the case of compounds with an SiNH fragment ψ-Bird pulse sequences, combined with HMQC or HSQC, served for 1H detection of the 29Si resonance with preselection of the 15N-1H spin pair. This permitted the measurement of 1J(29Si 15N) and the determination of its absolute sign (>0). In the absence of an NH group, the coupling constants 1J(29Si 15N) were measured from the 15N satellites in 29Si NMR spectra recorded by using the Hahn-echo extended (HEED) refocused INEPT pulse sequence. Isotope induced chemical shifts 1Δ 15/14N(29Si) were also measured by this technique for all the compounds. The 1J(29Si 15N) values cover the range 8.4–17.0 Hz, depending on the substituents at boron, silicon and nitrogen and on the complexation of the heterocycle.