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An unusual and complex tropane alkaloid pattern has been detected in the root bark of Astripomoea malvacea and in the whole plant of Falkia repens (Convolvulaceae) by GC-MS analysis. The specific profile of both species is characterized by the presence of aliphatic 3- acyloxytropanes/-nortropanes (exclusively in A. malvacea; predominantly in F. repens in cooccurrence with a few aromatic as well as arylalkyl acyl congeners). The principal alkaloid of A. malvacea, astrimalvine A N-oxide [3β -(3-tigloyloxy-2-methylbutyryloxy)tropane N-oxide], isolated and structurally elucidated by detailed spectroscopic analysis, represents the first N-oxide of a 3β -tropanol derivative in the Convolvulaceae. Its minor tertiary congener astrimalvine B [3β -(3-hydroxy-2-methylbutyryloxy)tropane] turned out to be a metabolite of both convolvulaceaous species. This is the first phytochemical report on the African genera Astripomoea and Falkia.

The response of the two most abundant cockchafer species in central Europe, Melolontha hippocastani and M. melolontha, towards phenol, mixtures of phenol with the leaf alcohol (Z)-3-hexen-1-ol and the known cockchafer pheromones, 1,4-benzoquinone (M. hippocastani) and toluquinone (M. melolontha), was investigated in the field. During the swarming period at dusk, phenol attracted males of both species, and enhanced the known attraction of cockchafer males towards (Z)-3-hexen-1-ol. A mixture of phenol plus (Z)-3-hexen-1-ol was less attractive for M. hippocastani males than a mixture of (Z)-3-hexen-1-ol plus 1,4- benzoquinone, whereas phenol plus (Z)-3-hexen-1-ol attracted as many M. melolontha males as a mixture of (Z)-3-hexen-1-ol plus toluquinone. In both species three component mixtures containing phenol, (Z)-3-hexen-1-ol, and the respective benzoquinone did not capture more males than two component mixtures consisting of only (Z)-3-hexen-1-ol and the benzoquinone. A possible role of phenol as another cockchafer sex pheromone component is discussed.

A synthetic mixture containing 1-indanone, 2-pentanone, 2-methyl-3-pentanone, 3-mcthyl- 2-pentanone, 2-methylcyclopentanone. 1-hydroxy-propanone. acetophenone, benzaldehyde. n-nonanal, n-decanal, nerolidol, eugenol, thymol, carvacrol and phythol deters oviposition of the Egyptian cotton leaf worm, Spodoptera littoralis (Boisd.). All compounds were identified from larval frass of S. littoralis.