Adrien Cave

Composés bromés de Rytiphlea tinctoria (Rhodophyceae)

Abstract Four aromatic bromo compounds have been isolated from the ethanolic extract of Rytiphlea tinctoria after treatment with diazomethane: 2,4-dibromo-1,3,5-trimethoxy-benzene,5,6,3′,5′-tetrabromo-3,4,2′,4′,6′-pentamethoxydiphenylmethane, 5,6-dibromo-3,4-dimethoxy-benzyl alcohol and its ethyl ether. In addition to sterols, amino acids, this extract also contains quinonoid bromo-pigments which could play a role in photosensitisation of chlorophylls, a role normally taken by the phycobilins, in other Rhodophyceae.

The fragmentation of NN-dimethyltryptamine oxide and related compounds: a possible implication in indole alkaloid biosynthesis

A modified Polonovski reaction on NN-di-methyltryptamine oxide and related compounds leads to products of fragmentation; the possible role of this new reaction in indole alkaloid biosynthesis is emphasized.

Alcaloïdes des feuilles de Holarrhena febrifuga

Abstract Leaves of Holarrhena febrifuga from East Africa contain 1·5% of alkaloids, mostly of the amino-3α ceto-20 pregnane-5α type. Six alkaloids have been isolated: funtumine (I), holamine (II), dimethyl- and monomethyl-funtumine (Ia) and (Ib), dimethyl- and monomethylholamine (IIa) and (IIb); these methyl derivatives have been isolated for the first time from natural source. Pregnane-3,20-dione has been isolated from the same leaves.