A2A receptor ligands: past, present and future trends.
The adenosine A(2A) receptor is a member of the G protein-coupled receptor family and mediates multiple physiological effects of adenosine, both at the central nervous system and at peripheral tissues. Increasing evidence relates the A(2A) receptor with several pathological conditions such as neurodegenerative disorders, inflammation, pharmacological stress, and wound healing renewing the interest in A(2A) receptor agonists and antagonists as promising leads for drugs. However some of them initially tested in clinical trials presented several side effects, short half-life, lower solubility, and in some cases a lack of effects, perhaps attributable to receptor desensitization or to low receptor density in the targeted tissue. For these reasons it is evident that additional rational chemical modifications of the existing A(2A) receptor ligands to improve their affinity/selectivity and bioavailability as well as further studies to get new template for A(2A)AR ligands are necessary. The purpose of this review is to analyze and summarize the past and the present aspects related to the medicinal chemistry of A(2A) receptor ligands. Moreover their current and possible therapeutic applications have been also highlighted.
Clementina
Manera
M
Department of Dipartimento di Scienze Farmaceutiche, Università di Pisa, via Bonanno 6, Pisa, Italy. manera@farm.unipi.it
Giuseppe
Saccomanni
S
D058908:Adenosine A2 Receptor Agonists; D058917:Adenosine A2 Receptor Antagonists; D004194:Disease / Q000209:etiology; D015195:Drug Design; D006801:Humans; D008024:Ligands; D043705:Receptor, Adenosine A2A / Q000187:drug effects* / Q000502:physiology; D013329:Structure-Activity Relationship
D058908:Adenosine A2 Receptor Agonists; D058917:Adenosine A2 Receptor Antagonists; D008024:Ligands; D043705:Receptor, Adenosine A2A