New Water-Soluble Condensed Heterocyclic Compounds with Antimicrobial Activity Based on Annulation Reactions of 8-Quinolinesulfenyl Halides with Natural Products and Alkenes

• Main Authors: Vladimir A. Potapov, Roman S. Ishigeev, Lyudmila A. Belovezhets, Irina V. Shkurchenko, Svetlana V. Amosova
• Format: Article
• Language: English
• Published: MDPI AG 2021-09-01
• Series: Applied Sciences
• Subjects: annulation reactions; [1,4]thiazino[2,3,4-<i>ij</i>]quinolin-4-ium derivatives; 8-quinolinesulfenyl chloride; heterocycles; natural products; alkenes
• Online Access: https://www.mdpi.com/2076-3417/11/18/8532

The annulation reactions of 8-quinolinesulfenyl halides with natural products and alkenes affording new water-soluble [1,4]thiazino[2,3,4-<i>ij</i>]quinolin-4-ium derivatives in high or quantitative yields are developed in this study. The reactions with styrene derivatives and terminal alkenes including allyl arenes proceed in a regioselective manner but with the opposite regiochemistry. The reactions with terminal alkenes including allyl arenes occur in an anti-Markovnikov fashion (regarding addition of the 8-quinolinesulfenyl electrophile to the double bond) to give 2-organyl-2<i>H</i>,3<i>H</i>-[1,4]thiazino[2,3,4-<i>ij</i>]quinolin-4-ium halides, while the reactions with styrene derivatives proceed in a Markovnikov fashion, leading to 3-substituted condensed heterocyclic compounds. In general, styrene derivatives demonstrate higher reactivity in the annulation reactions compared to the terminal alkenes. Antimicrobial activity of novel water-soluble compounds against <i>Enterococcus durans</i>, <i>Bacillus subtilis</i> and <i>Escherichia coli</i> are evaluated. The compounds with high antimicrobial activity are found. The annulation products of the reactions of 8-quinolinesulfenyl halides with 1<i>H</i>-indene, eugenol, methyl eugenol and 1-heptene, are superior in their activity compared to the antibiotic gentamicin.