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Updated: Jun 1, 2026

Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines
Published on: June 23, 2019
Synthesis, structure-affinity relationships, and molecular modeling studies of novel pyrazolo[3,4-c]quinoline
Ombretta Lenzi1, Vittoria Colotta, Daniela Catarzi
1Dipartimento di Scienze Farmaceutiche, Laboratorio di Progettazione, Sintesi e Studio di Eterocicli Biologicamente Attivi, Universita' di Firenze, Polo Scientifico, Via Ugo Schiff 6, 50019 Sesto Fiorentino, FI, Italy.
Abstract:
This paper reports the study of new 2-phenyl- and 2-methylpyrazolo[3,4-c]quinolin-4-ones (series A) and 4-amines (series B), designed as adenosine receptor (AR) antagonists. The synthesized compounds bear at the 6-position various groups, with different lipophilicity and steric hindrance, that were thought to increase human A(1) and A(2A) AR affinities and selectivities, with respect to those of the parent 6-unsubstituted compounds. In series A, this modification was not tolerated since it reduced AR affinity, while in series B it shifted the binding towards the hA(1) subtype. To rationalize the observed structure-affinity relationships, molecular docking studies at A(2A)AR-based homology models of the A(1) and A(3) ARs and at the A(2A)AR crystal structure were carried out.
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