Synthesis of intermediates for the core structure of Aspidosperma alkaloids

Alkaloids are naturally occurring chemical compounds containing nitrogen atoms.Biogenetically and structurally alkaloids are diverse. Indole alkaloids is one of major groupsof naturally occurring bioactive alkaloids . Aspidosperma type indole alkaloids constitute alarge group of alkaloids with important biological activities. The basic skeletal features ofthese alkaloids are pentacyclic framework. So far some genus of the Apocynaceae familymore than 250 aspidosperma alkaloids have been isolated.The Aspidosperma alkaloids have long been the target of synthetic studies due to theirstructural complexity and various biological activities. In this study, several precursors ofpyridocarbazole derivatives were synthesized for the synthesis of basic aspidospermaskeleton. Two different schemes were used for this aim. First scheme has six steps but thesecond one has only three steps. Both of schemes are functional. Different intermediates werecreated and six of which were synthesized for the first time. These intermediates are likely tohave different biological activities.Synthesized compounds were purified by using chromatographic methods and theirstructures were illuminated by using FT-IR and 1H-NMR.