New 1,4-Dihydropyridines Conjugated to Furoxanyl Moieties, Endowed with Both Nitric Oxide-like and Calcium Channel Antagonist Vasodilator Activities

• Published in: Journal of medicinal chemistry Vol. 41; no. 27; pp. 5393 - 5401
• Main Authors: Di Stilo, Antonella, Visentin, Sonja, Cena, Clara, Gasco, Andrea Marcello, Ermondi, Giuseppe, Gasco, Alberto
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 31.12.1998; Amer Chemical Soc
• Subjects: 4-Phenyl-1,4-dihydropyridines; Animals; Aorta, Thoracic - drug effects; Aorta, Thoracic - physiology; Binding, Competitive; Biological and medical sciences; Calcium Channel Blockers - chemical synthesis; Calcium Channel Blockers - chemistry; Calcium Channel Blockers - pharmacology; Cardiovascular system; Cerebral Cortex - metabolism; Chemistry, Medicinal; Dihydropyridines - chemical synthesis; Dihydropyridines - chemistry; Dihydropyridines - pharmacology; Enzyme Inhibitors - pharmacology; Guanylate Cyclase - antagonists & inhibitors; In Vitro Techniques; Life Sciences & Biomedicine; Male; Medical sciences; Methylene Blue - pharmacology; Miscellaneous; Muscle Contraction - drug effects; Muscle, Smooth, Vascular - drug effects; Muscle, Smooth, Vascular - physiology; Nifedipine - pharmacology; Nitric Oxide Donors - chemical synthesis; Nitric Oxide Donors - chemistry; Nitric Oxide Donors - pharmacology; Oxadiazoles - chemical synthesis; Oxadiazoles - chemistry; Oxadiazoles - pharmacology; Pharmacology & Pharmacy; Pharmacology. Drug treatments; Quinoxalines - pharmacology; Radioligand Assay; Rats; Rats, Wistar; Science & Technology; Structure-Activity Relationship; Vasodilator Agents - chemical synthesis; Vasodilator Agents - chemistry; Vasodilator Agents - pharmacology; UNSYMMETRICALLY SUBSTITUTED FUROXANS; DONORS; Vasodilator agent; Rat; Nitrogen heterocycle; Nitrone; Rodentia; Central nervous system; Calcium antagonist; Smooth muscle; In vitro; Vertebrata; Mammalia; Structure activity relation; Nitric oxide; Blood vessel; Diester; Aorta; Dihydropyridine derivatives; Chemical synthesis; Brain (vertebrata); Oxygen nitrogen heterocycle
• DOI: 10.1021/jm9803267
• ISSN: 0022-2623

A series of 4-phenyl-1,4-dihydropyridines substituted at the ortho and meta positions of the phenyl ring with NO-donating furoxan moieties and their non-NO-releasing furazan analogues were synthesized and pharmacologically characterized. The vasodilator activities of these compounds were evaluated on rat aorta and expressed as EC50 values or as EC50 iGC values when obtained in the presence of inhibitors of guanylate cyclase methylene blue (MB) and 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). Affinities to 1,4-DHP receptors on Ca2+ channels, expressed as IC50 values, were determined through displacement experiments of [3H]nitrendipine on rat cortex homogenates. A linear correlation between IC50 and EC50 values was found for compounds unable to release NO. EC50 calcd values for derivatives containing NO-donor moieties, expression of the Ca2+-blocking component of their vasodilator activity, were interpolated on this linear regression. They showed a good correspondence with EC50 iGC values determined in the presence of soluble guanylate cyclase inhibitors. Analysis of EC50 iGC/EC50 ratios provided a useful tool to distinguish well-balanced hybrids from derivatives biased toward Ca2+-blocking or NO-dependent vasodilator activity. A detrimental effect on affinity to the 1,4-DHP receptor, due to substitution at the ortho and meta positions of the 4-phenyl ring, was observed. SAR to explain this effect is proposed.