“…The same spectrum showed two pair of singlets at δ H 6.69 (1H, s, 1a ) and δ H 7.19 (1H, s, 1a ) and at δ H 6.76 (1H, s, 1b ) and δ H 7.14 (1H, s, 1b ) corresponding to the aromatic protons H-8 and H-5, respectively. The observation in the same spectrum of a triplet at δ H 5.02 (1H, t, J = 9 Hz, H-2', 1a ) and a multiplet at δ H 5.12 (1H, m, H-2', 1a ) a multiplet at δ H 3.10–3.30 (4H, m, H-3'a,b, 1a and 1b ) suggested the presence of the dihydrofuranic moiety in 1a and 1b [17,19,20,21,22,23,24]. These data and the observed duplication of all the signals are in good concordance with the dihydrofuranocoumarin structure of 1a and 1b .…”