title: A remarkable accelerating effect of Ag-salt on intramolecular cyclization of o-(1-alkynyl)benzenesulfonamides.
abstract: Herein, we report transition metal-catalyzed intramolecular cyclization of o-(1-alkynyl)benzenesulfonamides to afford 3-substituted benzothiazines regioselectively via a C-N bond forming reaction and Cu-catalyzed sequential C-N and C-C bond formation leading to the corresponding 3,4-disubstituted derivatives.
authors.affiliation: Chemistry-Discovery Research, Dr. Reddy's Laboratories Ltd., Bollaram Road, Miyapur, Hyderabad 500049, India.
authors.forename: Deepak Kumar
authors.initials: DK
authors.lastname: Barange
authors.forename: T C
authors.initials: TC
authors.lastname: Nishad
authors.forename: N Kumara
authors.initials: NK
authors.lastname: Swamy
authors.forename: Venkanna
authors.initials: V
authors.lastname: Bandameedi
authors.forename: Dinesh
authors.initials: D
authors.lastname: Kumar
authors.forename: Bukkapattanam R
authors.initials: BR
authors.lastname: Sreekanth
authors.forename: K
authors.initials: K
authors.lastname: Vyas
authors.forename: Manojit
authors.initials: M
authors.lastname: Pal
mesh_terms: D003300:Copper / Q000737:chemistry; D003500:Cyclization; D015394:Molecular Structure; D012492:Salts / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D013237:Stereoisomerism; D013449:Sulfonamides / Q000138:chemical synthesis* / Q000737:chemistry; D000096926:Benzenesulfonamides
chemical_list: D003300:Copper; D012492:Salts; D012834:Silver; D013449:Sulfonamides; D000096926:Benzenesulfonamides