40
2 Results and Discussion
HO
H
H
OH
O
H
H
H
O
H
Br
O
O
HO
X
H
H
O
H
OH
HO
R
2
R 1
H
H
O
H
OH
O
HO
Deprotection
Further
functionalisation
followed by
deprotection
Functionalisation
Oleanolic acid (5)
β-Hydroxy ketone (8b)
Hederagonic acid (1)
Higher oleananes (33a–d)
33
X
R
1
R
2
a
C− −O
α-OH
H
b
C− −O
β-OH
H
c
CH-β-OH
H
β-OH
d
CH-β-OH α-OH β-OH
Scheme 2.26: β-Hydroxy ketone 8b as potential branching point for routes to
higher members of the oleanane family (33a–d).
2 Results and Discussion
HO
H
H
OH
O
H
H
H
O
H
Br
O
O
HO
X
H
H
O
H
OH
HO
R
2
R 1
H
H
O
H
OH
O
HO
Deprotection
Further
functionalisation
followed by
deprotection
Functionalisation
Oleanolic acid (5)
β-Hydroxy ketone (8b)
Hederagonic acid (1)
Higher oleananes (33a–d)
33
X
R
1
R
2
a
C− −O
α-OH
H
b
C− −O
β-OH
H
c
CH-β-OH
H
β-OH
d
CH-β-OH α-OH β-OH
Scheme 2.26: β-Hydroxy ketone 8b as potential branching point for routes to
higher members of the oleanane family (33a–d).