Structure-activity relationships study of isothiocyanates for HS releasing properties: 3-Pyridyl-isothiocyanate as a new promising cardioprotective agent.

Introduction: The gasotransmitter hydrogen sulphide (HS), an endogenous ubiquitous signalling molecule, is known for its beneficial effects on different mammalian systems. HS exhibits cardioprotective activity against ischemia/reperfusion (I/R) or hypoxic injury.

Methods: A library of forty-five isothiocyanates, selected for their different chemical properties, has been evaluated for its hydrogen sulfide (HS) releasing capacity. The obtained results allowed to correlate several factors such as steric hindrance, electronic effects and position of the substituents to the observed HS production. Moreover, the chemical-physical profiles of the selected compounds have been studied by an in silico approach and from a combination of the obtained results, 3-pyridyl-isothiocyanate (25) has been selected as the most promising one. A detailed pharmacological characterization of its cardioprotective action has been performed.

Results: The results herein obtained strongly indicate 3-pyridyl-isothiocyanate (25) as a suitable pharmacological option in anti-ischemic therapy. The cardioprotective effects of compound 25 were tested in vivo and found to exhibit a positive effect.

Conclusion: Results strongly suggest that isothiocyanate-based HS-releasing drugs, such as compound 25, can trigger a ''pharmacological pre-conditioning" and could represent a suitable pharmacological option in antiischemic therapy.