Collect. Czech. Chem. Commun.
1984, 49, 2024-2039
https://doi.org/10.1135/cccc19842024
Minor diterpene components of the defense secretion from the frontal gland of soldiers of the species Nasutitermes costalis (HOLMGREN)
Irena Valterováa, Miloš Buděšínskýa, František Turečekb and Jan Vrkoča
a Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6
b The J. Heyrovský Institute of Physical Chemistry and Electrochemistry, Czechoslovak Academy of Sciences, 121 38 Prague 2
Abstract
Three minor components of the defense secretion from soldiers of the species Nasutermes costalis (HOLMGREN) have been isolated and characterized by means of spectral methods. The first component was identified as 1(15),8(19)-trinervitadien-9β-ol (III), known to occur with the subfamily Nasutitermitinae. For the second component two alternative structures IVa, IVb have been tentatively suggested, both with the 7,16-secotrinervitane skeleton. The third component was determined as 5β,9β-diacetoxy-2-oxo-11(12)kempen-20-oic acid (VII). The kempene skeleton was established on the basis of the 13C NMR spectrum and mass spectral fragmentation of the acid methyl ester. The relative configuration, together with a probable conformation of the tetracyclic framework were determined by 1H NMR. Two major tricyclic components, 1(15),8(19)-trinervitadien-2α,3β-diol (I) and 1(15),8(19)-trinervitadien-2α,3α-diol (II), were further characterized as mono and diacetates. Different rates of acetylation of the hydroxy groups in these diols provided evidence of stable conformation of the six-membered ring within the trinervitane skeleton.
