Pictet-Spengler reaction is one of the most versatile synthetic method in heterocyclic synthesis. Generally, tryptamine derivatives are known to react with aldehydes under acidic or neutral conditions to produce beta-calbolines. On the other hand, we have found that the reaction of Nb-benzylserotonin with aldehydes in the presence of a base proceeded the cyclization to the 4-position of the indole ring, producing azepino[5,4,3-cd]indoles. Therefore, we have investigated the applicability of other aldehydes and serotonin derivatives to the cyclization reaction to devise a novel synthetic route to azepinoindole alkaloids.