Atypical Parkinsonism in the Caribbean Island Guadeloupe is thought to be associated with the consumption of plants of the Annonaceae family, especially Annona maricata (soursop). In this study, a new aporphine alkaloid named annonamine (1) was isolated from the leaves of A. muricata L. together with four known benzylisoquinoline alkaloids (2-5). The structures of the isolated compounds were elucidated by the spectroscopic method.