Synthesis of 5-bromonaphthalimide derivatives with 3-aminocycloalkanespiro-5-hydantoins

¹ Department of Chemistry, Phytopharmacy, Ecology and Environmental Protection, Agricultural University – Plovdiv, 4000 Plovdiv, Bulgaria
² Department of Chemical, Food and Biotechnologies, Razgrad Branch, “Angel Kanchev” University of Ruse, 7200 Razgrad, Bulgaria

^* Corresponding author: m_n_marinov@abv.bg

Abstract

The present work reports a study on the interaction of 5-bromo-1H,3H-naphtho[1,8-cd]pyran-1,3-dione with various 3-aminocycloalkanespiro-5-hydantoins, aimed at the development of new biologically active compounds. As a result of this condensation, seven new 5-bromonaphthalimide derivatives were synthesized, namely: 5-bromo-2-(2,4-dioxo-1,3-diazaspiro[4.5]decan-3-yl)benzo[de]isoquinoline-1,3-dione, 5-bromo-2-(6-methyl-2,4-dioxo-1,3-diazaspiro[4.5]decan-3-yl)benzo[de]isoquinoline-1,3-dione, 5-bromo-2-(7-methyl-2,4-dioxo-1,3-diazaspiro[4.5]decan-3-yl)benzo[de]isoquinoline-1,3-dione, 5-bromo 2-(8-methyl-2,4-dioxo-1,3-diazaspiro[4.5]decan-3-yl)benzo[de]isoquinoline1,3-dione, 5-bromo-2-(8-ethyl-2,4-dioxo-1,3-diazaspiro[4.5]decan-3-yl)benzo[de]isoquinoline-1,3-dione, 5-bromo-2-(2,4-dioxo-8-propyl-1,3-diazaspiro[4.5]decan-3-yl)benzo[de]isoquinoline-1,3-dione, and 5-bromo-2-(2,4-dioxo-1,3-diazaspiro[4.7]dodecan-3-yl)benzo[de]isoquinoline-1,3-dione.The newly synthesized naphthalimides were characterized by physicochemical parameters as well as IR, ¹H NMR, and ¹³C NMR spectral data. The antimicrobial activity of the described compounds was evaluated against Gram-positive bacteria, Gram-negative bacteria, yeasts, and molds. The tested products exhibited the strongest activity against the Gram-positive bacteria Bacillus subtilis and Bacillus cereus.