Download full text in PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... IR, 1 H NMR (270 Mhz), and 13 C NMR (68 MHz) data for 4a–4f and 5a: 4a: (IR (KBr) 1622 cm −1 (νC=O); 1 H NMR (CDCl 3 ) δ 1.30 (s, 9 H), 3.86–3.96 (m, 4 H); 13 C NMR (CDCl 3 ) δ 26.19, 34.80, 44.92, 54.73 ( 1 J ( 125 Te, 13 C) = 154.2 Hz), 228.21. 4b: IR (neat) 1560 cm ...