The synthesis of some pyrrolo[1,2,3‐de]‐1,4‐benzothiazine derivatives by using a modified Bischler type cyclization of N‐(2,2‐diethoxyethyl)‐2H‐1,4‐benzothiazines as a crucial step is described. The alternative approach based on Friedel‐Crafts alkylation of the N‐(2‐chloroethyl)‐2H‐1,4‐benzothiazines is shown to be impractical due to the low yield obtained.

Cyclization reactions of N‐(2,2‐dialkoxyethyl)‐1,4‐benzothiazine lactams 2 and 1,4‐benzothiazine‐sulfones 10 lead to the corresponding pyrrolo[1,2,3‐de]‐1,4‐benzothiazines 4 and 12, respectively, by using the dioxane/p‐toluenesulfonic acid or polyphosphoric acid/chloroform systems. In contrast, in the same reaction conditions, 1,4‐benzothiazines 5a‐h do not provide the expected pyrrolobenzothiazines 7, and as for 5c‐h considerable amount of the 2‐amino‐phenyl‐sulfide 8 was obtained. The results of microbiological assays are reported.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.