Department of Chemistry and Process Technology, Mid Sweden University, 851 70 Sundsvall, Sweden.
The pine sawfly Neodiprion sertifer is a serious pest on Scots pine
(Pinus sylvestris). The larvae form colonies and feed on pine needles, sometimes
resulting in serious defoliation. The larvae sequester the resin from the needles in pouches
in the foregut and use this as a defence against predators such as wasps, ants, spiders and
birds1. The major sesquiterpene constituent of the defence substance was
found to be 1,6-germacradien-5-ol (1)2. Recently we
reported that the stereoisomer of (-)-1,6-germacradien-5-ol found in the defence substance
of N. sertifer and in the pine needle resin of Scots pine is
(5S, 8S)-13. Recent results
on our attempts towards the total synthesis of 1 will be presented.
1Codella, Jr., S. G.; Raffa, K. F. In Sawfly Life History. Adaptations to Woody
Plants; Wagner, M. and Raffa, K. F. Eds.; Academic Press: San Diego 1993; Chapter 10.
2Bergström, G.; Wassgren, A.-B.; Birgersson, G. Acta Chem. Scand.
1994, 48, 187-;188.
3Nordin, O.; Hedenström, E.; Högberg, H.-E. Acta Chem. Scand.
1999, 53, 124-132.