title: An improved synthesis of 4-chlorocoumarin-3-sulfonyl chloride and its reactions with different bidentate nucleophiles to give pyrido[1',2':2,3]- and thiazino[3',2':2,3]-1,2,4-thiadiazino[6,5-c]benzopyran-6-one 7,7-dioxides.
abstract: An improved synthetic method affording 4-chlorocoumarin-3-sulfonyl chloride (4) in very good yield (ca. 85%) is reported. This compound was reacted with various bidentate nucleophiles such as 2-aminopyridines and 2-aminothiazoles in order to obtain substituted pyrido- and thiazino-1,2,4-thiadiazino-benzopyranone dioxides (potential anticancer and anti-HIV agents). These reactions occurred rapidly at room temperature giving yellowish precipitates, which are insoluble in common organic solvents, making the purification process challenging. Further investigation has shown that these fused heterocycles are not stable and decompose with opening of the 1,2,4-thiadiazine ring.
authors.affiliation: Group of Physics and Chemistry, Faculty of Natural Sciences and Mathematics, State University of Tetova, 1200 Tetova, Macedonia. ahmed_alban@yahoo.com
authors.forename: Ahmed
authors.initials: A
authors.lastname: Jashari
authors.forename: Evamarie
authors.initials: E
authors.lastname: Hey-Hawkins
authors.forename: Bozhana
authors.initials: B
authors.lastname: Mikhova
authors.forename: Gerald
authors.initials: G
authors.lastname: Draeger
authors.forename: Emil
authors.initials: E
authors.lastname: Popovski
mesh_terms: D000631:Aminopyridines / Q000737:chemistry; D019380:Anti-HIV Agents / Q000138:chemical synthesis* / Q000737:chemistry; D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry; D001578:Benzopyrans / Q000138:chemical synthesis* / Q000737:chemistry; D003374:Coumarins / Q000138:chemical synthesis* / Q000737:chemistry; D013450:Sulfones / Q000138:chemical synthesis* / Q000737:chemistry; D013844:Thiazoles / Q000737:chemistry
chemical_list: C524608:4-chlorocoumarin-3-sulfonyl chloride; D000631:Aminopyridines; D019380:Anti-HIV Agents; D000970:Antineoplastic Agents; D001578:Benzopyrans; D003374:Coumarins; D013450:Sulfones; D013844:Thiazoles