Nucleophile-induced ring contraction in pyrrolo[2,1- c ][1,4]benzothiazines: access to pyrrolo[2,1- b ][1,3]benzothiazoles

• Published in: Beilstein journal of organic chemistry Vol. 19; no. 1; pp. 646 - 657
• Main Authors: Lystsova, Ekaterina A, Dmitriev, Maksim V, Maslivets, Andrey N, Khramtsova, Ekaterina E
• Format: Journal Article
• Language: English
• Published: Germany Beilstein-Institut zur Föerderung der Chemischen Wissenschaften 2023; Beilstein-Institut
• Subjects: 1,3-benzothiazole; 1,4-benzothiazine; 1h-pyrrole-2,3-diones; Alcohol; Cancer therapies; Chemistry; Full Research Paper; Nitrogen; nitrogen heterocycle; Nucleophiles; Pharmaceutical sciences; Pharmacology; Sulfur; sulfur heterocycle; Targeted cancer therapy; 1,3-benzothiazole; 1H-pyrrole-2,3-diones; sulfur heterocycle; 1,4-benzothiazine; nitrogen heterocycle
• ISSN: 1860-5397; 2195-951X; 1860-5397
• DOI: 10.3762/bjoc.19.46

Pyrrolo[2,1- ][1,3]benzothiazoles are an important class of fused sulfur and nitrogen-containing heterocycles intensively studied in medicinal chemistry and pharmacology. In the present paper, a new synthetic approach to pyrrolobenzothiazoles is developed based on 1,4-thiazine ring contraction in 3-aroylpyrrolo[2,1- ][1,4]benzothiazine-1,2,4-triones under the action of nucleophiles. The proposed approach works well with alkanols, benzylamine, and arylamines. The scope and limitations of the developed approach are studied. The synthesized pyrrolobenzothiazole derivatives represent an interest to pharmaceutics, since their close analogs show CENP-E inhibitory activity, interesting for the targeted cancer therapy development.