New [ g ]‐fused [1,2,4]triazolo[1,5‐ c ]pyrimidines: Synthesis of pyrido[3,2‐ e ] and [4,3‐ e ][1,2,4]triazolo[1,5‐ c ]pyrimidine, pyrimido[5,4‐ e ][1,2,4]triazolo[1,5‐ c ]pyrimidine and [1,2,4]triazolo[1,5‐ c ]pteridine derivatives

A number of 2‐aryl‐substituted pyrido[3,2‐ e ] and [4,3‐ e ][1,2,4]triazolo[1,5‐ c ]pyrimidines and [1,2,4]triazolo[1,5‐ c ]pteridines 11,12a,b,e , their corresponding 5‐carbonyl derivatives 7,8a,b,e and some pyrimido[5,4‐ e ][1,2,4]triazolo[1,5‐ c ]pyrimidin‐5‐ones 7,8c,d have been synthesized, according to different pathways. The new tricyclic heterocycles were prepared with the aim of studying their possible benzodiazepine receptors affinity.