title: [Synthesis and preliminary pharmacological screening of 2,4-disubstituted N,N-dialkyl-1,8-naphthyridine-3-carboxamides].
abstract: By treating at 100 degrees C 2-aminonicotinic acid with ethyl N,N-dialkylmalonamate (I) and phosphorus oxychloride N,N-dialkyl-4-chloro-1,2-dihydro-2-oxo-1,8-naphthyridine- 3-carboxamides (II) were obtained. The reaction of compounds (II) with an excess of refluxing phosphorus oxychloride afforded N,N-dialkyl-2,4-dichloro-1,8-naphthyridine-3-carboxamides (III), which in turn were treated at room temperature with excess primary amines to give a mixture of isomeric N,N-dialkyl-2-(alkylamino or cycloalkylamino)-4-chloro-1,8-naphthyridine-3-carboxamides (IV) and N,N-dialkyl-4-(alkylamino or cycloalkylamino)-2-chloro-1,8-naphthyridine-3-carboxamides (V). When this last reaction was performed at 160 degrees C, only N,N-dialkyl-2,4-bis(alkylamino or cycloalkylamino)-1,8-naphthyridine-3-carboxamides (VI) were obtained; under the same conditions (IV c) or (V c) reacted with methylamine to give isomeric 2,4-bis(alkylamino)derivatives (VII) or (VIII), respectively. Compounds (II b), (III b), (IV a,c,d), (V a,c,d) were submitted to a wide preliminary pharmacological screening. Some of them, depending on the structure, showed antihypertensive [(IV c)], anti-inflammatory [(IV c) greater than (III b)], or, in the behavioral test, anti-aggressive [(IV d) greater than (III b)] activity. Furthermore compound (III b) caused moderate inhibition of the 5-HT induced contraction of the guinea-pig ileum.
authors.affiliation: Istituto di Scienze Farmaceutiche, Università di Genova.
authors.forename: M
authors.initials: M
authors.lastname: Di Braccio
authors.forename: G
authors.initials: G
authors.lastname: Roma
authors.forename: A
authors.initials: A
authors.lastname: Balbi
authors.forename: E
authors.initials: E
authors.lastname: Sottofattori
authors.forename: M
authors.initials: M
authors.lastname: Carazzone
mesh_terms: D000374:Aggression / Q000187:drug effects*; D000578:Amidines / Q000138:chemical synthesis* / Q000494:pharmacology; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000138:chemical synthesis*; D000959:Antihypertensive Agents / Q000138:chemical synthesis*; D055598:Chemical Phenomena; D002621:Chemistry; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D009287:Naphthyridines / Q000138:chemical synthesis* / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains; D012702:Serotonin Antagonists / Q000138:chemical synthesis
chemical_list: D000578:Amidines; D000894:Anti-Inflammatory Agents, Non-Steroidal; D000959:Antihypertensive Agents; D009287:Naphthyridines; D012702:Serotonin Antagonists
vernacular_title: Sintesi ed esame farmacologico preliminare di N,N-dialchil-1,8-naftiridin-3-carbossammidi 2,4-disostituite.