Characterisation of furoxancarbonitriles as a new class of vasodilators

The synthesis, structural characterization, NO-donor properties, and in vitro vasodilating activities of a series of furoxancarbonitriles 2, 17-22a, b are reported. Some derivatives (2b, 2a, 18b, 21b, 22b) are more potent vasodilating agents than sodium nitroprusside (SNP), the reference compound, some others display similar potency (17b, 19b, 20b). Log EC 50 values fit well on the linear correlation log EC 50 versus log C 0.1 1min (namely the logarithm of the concentration able to release 2.6 μmol l -1 min -1 of NO) found in a previous work. The haemodynamic profile in anaesthetised pigs for some selected derivatives (2a, b, 19a, b) is also presented. These profiles are consistent with that known for another furoxan NO-donor (4-hydroxymethyl-3furoxancarboxamide, CAS 1609) and suggest similar characteristic of in vivo NO-release.