10 0 - EleA@UniSA - Università degli Studi di Salerno

CHO
OH
CHO
3
CHO
CHO
CHO
AcO
AcO
1.13 1.14 1.15
FIGURE 1.11-Some metabolites from Canella winteriana
For these compounds some studies toward structure activity relationship have
been reported.
It has been demonstrated that the dialdehyde is an essential moiety, no
phytotoxic activity was shown by other metabolites with just one aldehyde group
or protected as acetals or cyclised to form a lactone ring.
In addition, theconfiguration of 9-CHO is important for the activity, in fact the
C-9 epimer of 1.14 is much less active than 1.14 itself because of different
stereochemistry at C-9 carbon.
It seems that the orientation of the acetyl group is important for bioactivity: in
fact compound 1.15, the epimer of 1.14 with a different stereochemistry at C-3
15, 16
is not active.
Some sesquiterpenoidic dialdehydes have been isolated also from fungi.
Isovelleral (1.4) and velleral (1.16) have been isolated from fungus Lactarius
vellereus, piperdial (1.17) from Lactarius piperatus and epi-piperdial (1.18) from
Lactarius necator. (Figure 1.12)
15 Ying; B.P; Peiser, G; Yuan; J.Y., Mathias,K; Tutko, D. Phitochem. 1995 38, 900.
16 Ying, B.P.; Peiser, G.D.;Yuan, Y, J.;Mathias, Karesina, F. J. Agric. Food. Chem.1995, 43,826.
3
CHO
20