title: A journey from benzanilides to dithiobenzanilides: Synthesis of selective spasmolytic compounds.
abstract: A series of dithiobenzanilide derivatives was synthesized and each compound was evaluated for its ability to reduce KCl-induced contractions of smooth muscle preparations of the guinea pig. Starting from a recent publication describing benzanilide derivatives as antispasmodic agents, structure-activity guided synthesis was performed to obtain compounds with improved spasmolytic activity. First, compounds with two amide bonds were designed and second, both amide oxygens were replaced by two sp² sulfur atoms resulting in dithiobenzanilide derivatives. The most potent antispasmodic dithiobenzanilide 19 showed improved activity with an IC₅₀ value of 0.4 μM. Moreover, the study also demonstrated that these active compounds were able to antagonize the effect of spasmogens like acetylcholine and phenylephrine and that the activity is not mediated by activation of ATP-dependent potassium channels (K(ATP)-channels) or inhibition of endothelial nitric oxide synthase (eNOS).
authors.affiliation: Department of Medicinal Chemistry, University of Vienna, Austria.
authors.forename: Gerda
authors.initials: G
authors.lastname: Brunhofer
authors.forename: Walter H
authors.initials: WH
authors.lastname: Granig
authors.forename: Christian R
authors.initials: CR
authors.lastname: Studenik
authors.forename: Thomas
authors.initials: T
authors.lastname: Erker
mesh_terms: D000813:Anilides / Q000737:chemistry*; D000818:Animals; D001555:Benzene Derivatives / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D006168:Guinea Pigs; D054086:KATP Channels / Q000737:chemistry / Q000378:metabolism; D009130:Muscle, Smooth / Q000187:drug effects; D009465:Neuromuscular Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D052250:Nitric Oxide Synthase Type III / Q000037:antagonists & inhibitors / Q000378:metabolism; D013329:Structure-Activity Relationship; D013854:Thioamides / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D000813:Anilides; D001555:Benzene Derivatives; D054086:KATP Channels; C557928:N,N'-(1,2-phenylene)bis(3,4,5-trifluorobenzothioamide); D009465:Neuromuscular Agents; D013854:Thioamides; C034595:benzanilide; D052250:Nitric Oxide Synthase Type III