[Simple compounds with high pharmacologic potential: beta-carbolines. Origins, syntheses, biological properties]

We reviewed the origins, the synthetic pathways and the biological properties of beta-carbolines, the condensation products of tryptophan and indole alkylamines with aldehydes. They were found in many plants, some of which have been used as hallucinogens. They also occur as minor constituents in tobacco smoke. In mammalian body, beta-carboline derivatives occur normally in plasma, platelets and urine, moreover it seems that some are formed in human body after alcohol intake. Due to interesting biological effects described in recent years (inhibition of monoamine oxidase, binding to benzodiazepine receptors, comutagenic and carcinogenic properties, 5-hydroxy tryptamine uptake inhibition), many attempts were made to prepare beta-carbolines starting from various indole derivatives. We reviewed the published methods up to 1975 and summarized the main patents related with pharmacological properties of synthetic beta-carbolines.