Action of calycanthine on nervous transmission in cockroach central nervous system.

Calycanthine, the principal alkaloid of the order Calycanthaceae, has been isolated from a species of the genus Psychotria (Rubiaceae) occurring in some Pacific islands. The drug is considered as a very powerful convulsant poison but very little is known about its mechanism of action. The symptoms observed were similar to those of some neuropoisons such as strychnine. The properties of this alkaloid have been investigated on the genesis, conduction, and transmission of the nerve impulse, using giant axons of the cockroach (Periplaneta americana). Calycanthine hydrochloride (10(-5) M), which did not alter nervous conduction in pre- and post-synaptic fibers, significantly reduced the efficacy of the synaptic transmission.

In vitro cytotoxicity of polyindolenine alkaloids on rat hepatoma cell lines. Structure activity relationships.

New groups of polyindolenine alkaloids have been isolated from new species of the tribe Psychotriae (Rubiaceae). The cyto-inhibitory effects of these compounds on tumoral cell lines have been thoroughly investigated and thus allow the statement of relationships between some original structural patterns and the observed biological effects.

New Polyindolenine Alkaloids from Calycodendron milnei.

Four new alkaloids, representing the first members of new groups of polyindolinic alkaloids, have been isolated from the aerial parts of CALYCODENDRON MILNEI along with other alkaloids. The names vatine, its stereoisomer vatine A, vatamine, and vatamidine are proposed. They are polymers of six, seven, and eight N(b)-methyltryptamine units, respectively.