Lytta Vesicatoria

Sierra J. R., Woggon W.-D. and Schmid H. (1976) Transfer of cantharidin during copulation from the adult male to the female Lytta vesicatoria (Spanish flies). Experientia 32, 142-144. 

Cantharidin is obtained from cantharides, the dried beetle Cantharis vesicatoria ( = Lytta vesicatoria) (Meloidae) or other spp., containing not less than 0.6%, or from mylabris, the dried beetles Mylabris sidae = M. phalerata), M. cichorii and M. pustulata (Meloidae), containing not less than 1%,... 

The powdered bodies of Mylabris mongolica, when extracted under alkali (not NH3) conditions afforded cantharidinimide (120), and the same substance was also isolated from cantharis (Lytta vesicatoria) (112). The IR spectrum showed bands at 1760, 1710, and 1698 cm 1, the mass spectrum displayed an M+ at m/z 195, and the H NMR spectrum indicated the high symmetry of the isolate, showing a six-proton singlet at 1.25 ppm and a two-proton multiplet at 4.65 ppm for the oxymethine protons. 

Recent biosynthetic investigations have revealed that cantharidin (635), a well-known vesicant compound isolated from dried beetles (Lytta vesicatoria L.), can be regarded as a degraded sesquiterpenoid. Thus the labelling pattern in cantharidin (635) after incorporation of [2- C]mevalonic acid (35) and (E,E)-[ir,12- H2]farnesol (16) [but not the E,Z)- or (Z,Z)-isomers ] is consistent with the biosynthetic sequence outlined in Scheme 67. ... 

Synthesized in the meloid beetle Lytta vesicatoria present in the blood, released by reflex bleeding from joints, feeding deterrent... 

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