Synthesis of 3-(substituted methyl)-2-phenyl-4H-1-benzothiopyran-4-ones

Article abstract of DOI:10.1246/bcsj.57.2323

Reaction of 2-phenyl-4H-1-benzothiopyran-4-ones and related compounds with chloromethyl methyl ether and fuming sulfuric acid gave mainly the 3-chloromethyl compound, whereas chloromethylation of methoxy-substituted thioflavones took place at another position or gave the tris(chloromethyl) compound. 3-(Chloromethyl)thioflavone could be easily converted into various 3-(substituted methyl)thioflavones which showed significant antimicrobial activity against Trichophytons.