Abstract
Pharmacological properties of several guanethidine derivatives were examined with [2-(hexahydro-1H-azepin-1-yl) ethyl] guanidine sulfate (G-7), [2-(4-methyl-(G-7-CH3), [2-(3, 5-dimethyl-(G-7-(CH3)2), [2-(4-methyl-4-aza-(G-7-N), [2-{4-(p-chlorophenyl)-(G-7-2), -hexahydro-1H-azepin-1-yl} ethyl] guanidine sulfate, [2-(hexahydro-1, 4-thiazepin-1-yl)-(G-7-S), [2-(1-oxo-hexahydro-1, 4-thiazepin-4-yl)-(G-7-SO), [2-(1, 1-dioxo-hexahydro-1, 4-thiazepin-4-yl)-(G-7-SO2), -ethyl] guanidine sulfate and [2-(1, 8, 8-trimethyl-3-aza-bicyclo [3. 2. 1] oct-3-yl) ethyl] guanidine sulfate (G-7-3).
Among the compounds, G-7-N and G-7-2 showed a hypotensive action on rabbit, rat and cat, but their activities were weaker than that of guanethidine. Unlikely to the case of guanethidine, pressor action of noradrenaline was not potentiated and that of tyramine was not inhibited by G-7-N and G-7-2.
G-7-2 and G-7-3 possessed a marked muscle relaxation on N. ishiadicus-sartorius preparation of Rana nigromaculata. Their activities were found to be almost the same as that of succinylcholine chloride.
Analgesic, antitussive, antispasmodic activities were also tested, but their effects were found to be not so strong.
In general, an introduction of substituents in seven-membered ring resulted in a decrease of hypotensive activities and an increase of toxicities.
