The major alkaloid of a Fijian Melodinus sp. (family Apocynaceae) has been identified as (+)-scandine (1). The crystal structure and absolute configuration of the acetone solvate of (+)-scandine hydrobromide have been determined by X-ray diffraction; diffractometer data at 295 K were refined by block diagonal least squares to a residual of 0,037 (2657 'observed' reflections). Crystals of the hydrobromide are monoclinic, P 2,, a 9.496(3), b 14.561(5), c 9.339(3) A, p 115.39(2)", Z 2.Although the cations of (+)-scandine hydrobromide and (+)-N-methylmeloscine bromide have the same skeleton and the same absolute configuration, they have different conformations; this appears to be due to the steric effect of the N-methyl group in the latter cation.

Three new serrulatane diterpenes have been isolated from Eremophila species. Evidence is presented for the structure of (15S)-7,8,16-trihydroxyserrulatan-19-oic acid, isolated as its methyl ester from E. drummondii, serrulat-14-ene-7,8,20-trio1 from E. linearis Chinnock and for (2S)-serrulat-14-ene- 2,7,8,20-tetraol from E. granitica.

Dihydroxyserrulatic acid (1), a diterpene from Eremophila serrulata, has been degraded to the naphthalene (2) which was shown to have the R-configuration. The diterpene acid can now be designated as (5R,8S,1'S)-4-hydroxy-8-(6'-hydroxy-1',5'-dimethylhex-4-enyl)-5-methyl-5,6,7,8-tetrahydronaphthalene-2-carboxylic acid.

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The structure of a new eremane diterpene isolated from Eremophila cuneifolia Kraenzlin has been determined by X-ray crystallographic methods. The conversion of this diterpene into sesquiterpeneswith the same tricyclic skeleton is described.