“…In the spectra of 1 H-1 H COSY compounds, spin-spin correlations are observed through three bonds of the neighboring methyl and methylene protons of the ethyl carboxylate fragments H 15,18 -H 14,17 with coordinates at 1.11, 4.01 and 4.00, 1.14 ppm. Heteronuclear interactions of protons with carbon atoms through one bond were established using 1 H- 13 C HMQC spectroscopy for all pairs present in the compound: H 15,18 -C 15,18 (1.14, 14.92), H 7,12 -C 7,12 (2.06, 18.47) , H 4 -C 4 (3.06, 25.24) and H 14,17 -C 14,17 In the 1 H NMR spectrum of compound 2, the equivalent methyl protons H-15, 15, 15, 18, 18, 18, 18 of the ethyl carboxylate groups showed a six-proton triplet at 1.28 ppm with 3 J 6.8 Hz (Fig. 3).…”