A new cyclopeptide alkaloid, sanjoinine-G1, has been isolated from the seeds of Zizyphus vulgaris var. spinosus. The structure and absolute configuration has been established by spectroscopic analysis and the circular dichroism exiton-coupling method, as N-[(S)-(N',N')-dimethylphenylalanyl]-cyclo[O-(2S, 3S)-beta-oxyleucyl-(S)-leucyl-(2-mino-(1R)-hydroxyethyl)-p-phenyl]. Copyright (C) 1996 Elsevier Science Ltd