FK453: A Novel Non‐Xanthine Adenosine A₁ Receptor Antagonist as Diuretic

Synthesis and 3D QSAR of New Pyrazolo[3,4-b]pyridines: Potent and Selective Inhibitors of A1 Adenosine Receptors

“…A 1 AR antagonists have therapeutic potential in the treatment of various form of dementia, such as the Alzheimer's disease, , depression, and as cognition enhancers in geriatric therapy . Moreover, A 1 AR antagonists are currently studied as potassium-saving diuretics and for the treatment of acute renal failure . 4-Amino-substituted pyrazolo[3,4- b ]pyridines, as tracazolate, etazolate, and cartazolate, were originally identified as A 1 AR antagonists, during a wide screening on nitrogenated heterocyclic molecules related to purinic derivatives.…”

“…11 Moreover, A 1 -AR antagonists are currently studied as potassiumsaving diuretics and for the treatment of acute renal failure. 12 4-Amino-substituted pyrazolo [3,4-b]pyridines, as tracazolate, etazolate, and cartazolate, were originally identified as A 1 AR antagonists, 13 during a wide screening on nitrogenated heterocyclic molecules related to purinic derivatives. Subsequently, a plethora of additional pyrazolo [3,4-b]pyridines has been also synthesized, among which the most active compound possess affinity of 0.3 µM for A 1 AR, but scarce selectivity.…”

Synthesis of 5,6-Dihydropyrazolo[5,1-a]isoquinolines through Indium(III)-Promoted Halocyclizations of N-Propargylic Sulfonylhydrazones

“…Among those pyrazole derivatives, compounds based on the pyrazolo­[1,5- a ]­pyridine framework have attracted increasing attention due to their promising biological activities. Typical examples of bioactive pyrazolo­[1,5- a ]­pyridines include the well-known antiallergic and cerebroactive agent ibudilast, the novel adenosine A1 receptor antagonist FK838, the adenosine antagonist FK453, and a series of highly selective D4 receptors ligands . Although several strategies have been developed for the synthesis of 5,6-dihydropyrazolo­[5,1- a ] isoquinoline, they usually rely on the functionalization of substrates with the preinstalled pyrazole or 3,4-dihydroisoquinoline ring.…”