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Updated: Aug 13, 2026

Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines
Published on: June 23, 2019
An improved synthesis of alpha-carbolines under microwave irradiation
Patricia Vera-Luque1, Ramón Alajarín, Julio Alvarez-Builla
1Departamento de Química Orgánica, Universidad de Alcalá, 28871-Alcalá de Henares, Madrid, Spain.
Abstract:
[reaction: see text]. Alpha-carbolines are interesting core structures for designing DNA-interacting small molecules. However, these compounds are not commercially available and their synthetic methods are low yielding or time consuming. The shortest synthetic route, the modified Graebe-Ullmann reaction, has been optimized by using microwave heating in four different types of apparatus to give shorter reaction times and enhanced yields. Optimized conditions enabled the preparation of a small library of alpha-carbolines.
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