Six new alkaloids have been isolated and identified in the leaves ofAlstonia undulata from New Caledonia. They are 10-hydroxypericyclivine,N(1)-methyl-10-hydroxypericyclivine, 10-methoxypericyclivine,N(1)-methyl-10-methoxypericyclivine,N(1)-methyl 16-epipericyclivine and voachalotinal. The last two alkaloids are identical to hemisynthetic products derived from quebrachidine. Stereochemistry at C-16 ofN(1)-methyl 16-epipericyclivine has been proved by a chemical correlation. © 1990 Pergamon Press plc.