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The proton NMR data for compound III was similar to that in the literature with the
exception of the resonance for the methylene group at C-6 (Table 19). Ansell (1989)
reported 2H-6 having a resonance of δΗ 2.37 (ddd, J = 2.3, 3.3, 13.2 Hz) while in
compound III, the methylene group at C-6 resonated as singlets at δΗ 1.38 and δΗ 1.63
(Table 19). The 13 C NMR data was not reported in the literature and therefore the
diacetylated compound was used for comparison (Table 19). Due to insufficient sample,
compound III could not be acetylated for absolute comparison.
In comparing our compound to that of literature, we have had to make an assumption that
the compound in the literature had the hydroxyl groups in the equatorial positions (3β and
11α) as concluded in the discussion and not by what was depicted in the structure. The
discussion of the compound in Ansell (1989) did not match the structure (where the
hydroxyl groups were axial, 3α and 11β). The 13 C NMR data also compared well to
similar compounds 3.1 to 3.3 (Table 20, pages 118 and 119).
Table 19: NMR data of compound III (CDCl3) and its acetylated equivalent
Position Moiety
1 CH2
2 CH2
3 CH-OH
Compound III
(400MHz)
2.35
2.02
1.69
1.57
3.26, dd
(J = 3.84, 10.84 Hz)
1 H
Ansell, 1989
(80MHz)
3.26, sx
(J = 5.3, 9.7, Hz)
Compound III
(400MHz)
13 C
# Ansell, 1989
(20MHz)
35.74 36.5
27.59 24.0
78.86 80.6
*4 C 39.11 38.0
5 CH 1.08 53.99 54.0
6 CH2
1.63
1.38
2.37, ddd
(J = 2.3, 3.3, 13.2 Hz) 22.55 22.4
7 CH2
1.48
1.85
38.38 35.6
8 C=C 137.46 136.4
9 CH 1.61 59.83 55.4
*10 C 39.05 38.7
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