1. BIOSYNTHESIS OF
OPIUM ALKALOIDS

2. * * * * * * * * 14C-Tyrosine fed to opium poppy seedlings
Two labels are
incorporated into
papaverine and
norlaudanosoline,
implying that two
tyrosines are used.
14C-Tyrosine fed to
opium poppy seedlings *
hydroxylase
tyrosine O2
If labeled DOPA is fed
only one label is found. *
PLP
DOPA
PLP * *
Mannich + Arom. Subst.
dopamine * *
thebaine
SAM * *
FAD
codeine
papaverine
norlaudanosoline
morphine
(in all poppies)

3. 14CO2 FEEDING EXPERIMENT This order was established by growing
the poppies in a greenhouse with 14CO2
and watching the order of appearance
and buildup of the the radioactivity
At first the rate of incorporation is greater
for thebaine than for codeine or morphine.
After several days, the rate of incorporation
into morphine is greatest. This indicates
that thebaine is formed first, and that codeine
and morphine follow in order.
norlaudanosoline
thebaine
The same result is obtained with carbon-14
labeled tyrosine.
codeine
morphine
Also, labeled thebaine is converted to both
codeine and morphine, but not the other way
around.
Finally, codeine is demethylated to morphine;
the reverse is not observed.

4. * * * * * * * * * * redrawn (folded) on the next slide ….. SAM FAD
norlaudanosoline
laudanosine
papaverine
SAM
Norlaudanosoline is incorporated
into papaverine and thebaine at a
higher rate than tyrosine - it’s closer. * *
redrawn (folded)
on the next slide ….. * *
SAM
In a separate set of experiments,
it can be shown that the methyl
groups originate from methionine
(14C labeled CH3) and hence SAM.
laudanosoline
(-)-reticulene

5. . . MULTIPLE LABELS * * * * not an easy synthesis !
thebaine
(all labels intact !)
(-)-reticulene (5 labels)
not an easy synthesis !
When multiple labels survive intact it is a good indication
that the incorporation study is a very valid one!

6. . . . . OXIDATIVE COUPLING * * * . . * * * * * [O] coupling
enolization
(-)-reticulene (5 labels) * . *
salutaridine

7. . . . * * * * * * ORIGINAL HYPOTHESIS (ALA PUMMERERS KETONE) THEBAINE
IT MISLEAD THEM * * . .
Michael
addition * *
(+)-salutaridine
NADPH * .
-H2O
THEBAINE * H+

8. . . . * * * * * * REVISION OF ROUTE TO THEBAINE THEBAINE NADPH
salutaridinol * *
(+)-salutaridine
allylic
displacement
Labeled salutaridine is
incorporated at a high
rate into thebaine,
codeine and morphine. * .
Labeled salutaridinol
(both -OH epimers) is
also incorporated at a
high rate.
THEBAINE *

9. THE FINAL INTERCONVERSIONS
+ H2O
- H2O
neopinone
thebaine
hemiketal
isomerization
of double bond
demethylation
NADPH
morphine
codeine
codeinone
Labeled neopinone is converted to codeine in the plant.

10. . . . . ANOTHER REVISION * * * * * * * * TRITIUM IS LOST TRITIUM+ * * *
(+)-reticulene
1,2-dihydroreticulene
(-)-reticulene
TRITIUM
IS LOST * .
(+)-Reticulene appears to be
formed first, and than converted
to (-)-reticulene through the
1,2-dihydroreticulene intermediate.
TRITIUM
SURVIVES *
(-)-Reticulene is incorporated with
the tritium label intact. (+)-Reticulene
loses the label.
(-)-reticulene

11. WHAT WAS NOT SHOWN Remember, each of the labeled compounds had to be
synthesized with high specificity.
Dilution compounds had to isolated or synthesized.
Each of the destination compounds had to be specifically
degraded to find the position of the label.
At times the percentage incorporation was important to
know - this requires painstaking work.
Most times, fortunately, it is sufficient just to know where
the label ended up.
All of these plants had to be grown and tended to.
Manipulation of radioactive waste was a major problem
(14C has a half-life of 5730 years) it doesn’t go away if spilled.

12. Much of this work was done by
Sir Alan Rushton Battersby
(b. 1925) and his co-workers.
Manchester College, England
Ph.D. Dundee (1959)
Reader at Bristol, Liverpool and
Cambridge
OPTIONAL READING
A.R. Battersby and B.J.T. Harper,
“Biogenesis of Morphine”, Chemistry and Industry
1958, 364.
A.R. Battersby, R. Binks, D.J.Le Count,
“Biosynthesis of Morphine”,
Proceedings of the Chemical Society, 1960, 287.

13. Alkaloids - Nature’s Cure or Curse, Wiley-VCH (2000)
ASSIGNMENTS
Read:
Hesse
Alkaloids - Nature’s Cure or Curse, Wiley-VCH (2000)
“Alkaloid Biogenesis in Papaver Somniferum”, pp
Two of the degradation procedures will be found
here in Figures 8.16 (C9) and 8.17 (C16). You will
already be familiar with some of this chemistry as
we learned it in the discussion of the structure
proof of morphine.