A new subgroup of the Amaryllidaceae alkaloids having a 10b,4a-ethanoi
minodibenzo[b, d] pyrane (2-benzopyrano[3,4-d]indole) nucleus is isola
ted from two different Galanthus species as three novel monomeric alka
loids, (+)-graciline (1), (+)-11-acetoxygraciline (2) and (+)-3,4-dihy
dro-3-hydroxygraciline (3). The fourth new compound, (-)-digracine (4)
is a dimer of two such moieties.