Aporphine
Aporphine is an alkaloid that forms the core of a class of quinoline alkaloids. It can exist in either of two enantiomeric forms, -aporphine and -aporphine.
Many different derivatives have been isolated from plants. For example, many water-lilies produce aporphine alkaloids such as nymphaeine, nymphaline, nupharine, α- and β-nupharidine.
In vitro tests of some aporphine derivatives isolated from Cassytha filiformis, namely actinodaphnine, cassythine, and dicentrine, showed antiparasitic activity against Trypanosoma brucei. Investigation of possible mechanisms revealed that the compounds bind to DNA and act as intercalating agents, besides inhibiting topoisomerase activity.
-Aporphine is a dopamine receptor D1 antagonist with a Ki of 717 nM and a dopamine receptor D2 antagonist with a Ki of 527 nM. Aporphine and its related alkaloids bulbocapnine, boldine, glaucine, and corytuberine are antipsychotic, exert naloxone-reversible antinociceptive activity, and with the exception of corytuberine are anticonvulsant. Some derivatives of aporphine such as --N-propylnorapomorphine have potential as low side effect profile antipsychotics. --N-Propylnorapomorphine is highly selective for meso-limbic dopaminergic tracts and function as efficacious partial agonists, with no elevation in prolactin.
