276 Acta Chim. Slov. 2020, 67, 276–282 Moghaddam-Manesh et al.: Synthesis, Characterization and Antimicrobial ... DOI: 10.17344/acsi.2019.5437 Scientific paper Synthesis, Characterization and Antimicrobial Evaluation of Novel 6’-Amino-spiro[indeno[1,2-b] quinoxaline[1,3]dithiine]-5’-carbonitrile Derivatives Mohammadreza Moghaddam-Manesh, Dadkhoda Ghazanfari, * Enayatollah Sheikhhosseini and Mohammadreza Akhgar Department of Chemistry, Kerman Branch, Islamic Azad University, Kerman, Iran * Corresponding author: E-mail: dadkhodaghbk@yahoo.com Tel: +98 31321328, fax: +9831321405 Received: 07-23-2019 Abstract l,3-Dithiin with two sulfurs in its structure is a six-membered, sulfur-containing heterocyclic compound. New deriv- atives of 6’-amino-2’-(arylidene)spiro[indeno[1,2-b]quinoxaline[1,3]dithiine]-5’-carbonitrile were prepared by the multi-component reaction of active methylene compounds, carbon disulfide, malononitrile and multi-ring compounds containing a carbonyl group in the presence of piperidine as a catalyst at room temperature with high efficiency. e antimicrobial effects including antibacterial and antifungal effects based on inhibition zone diameter (IZD), minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) were studied. Keywords: Multicomponent reaction; sulfur-containing heterocyclic; spiro[indeno[1,2-b]quinoxaline[1,3]dithi- ine]-5’-carbonitrile; carbon disulfide; antimicrobial activity 1. Introduction Heterocyclic compounds are highly valuable consid- ering their use as a key ingredient in medications. 1 Sul- fur-containing heterocyclic compounds are particularly noteworthy in organic chemistry, medicine, and biochem- istry due to their structure. 2–3 Spiro heterocyclic com- pounds lead to the biological activity of these compounds because of the commonality of a carbon between the two rings and the lack of symmetry of these compounds due to the asymmetric nature of carbon spiro compounds. 4–8 Bi- ological activities, such as promising antibacterial, anti- fungal, 9–11 anti-hyperglycemic, 12 and anti-tubercular 13 ef- fects have been reported for spiro heterocyclic compounds. l,3-Dithiin is a six-membered sulfur-containing het- erocyclic ring with two sulfur atoms at positions 1 and 3. is heterocyclic compound has been reported as an anti- thrombotic agent found in Allium sativum. 14 Other bio- logical properties have also been reported for synthesized heterocyclic compounds containing l,3-dithiin ring. 15–17 ese compounds are most oſten used as a carbon protec- tion groups for the synthesis of heterocyclic com- pounds. 18–20 In this study the new derivatives of 6’-amino-2’- (arylidene)spiro[indeno[1,2- b]quinoxaline[1,3]dithi- ine]-5’-carbonitrile were synthesized using compounds possessing active methylene group, carbon disulfide, malononitrile, 11H-indeno[1,2-b]quinoxalin-11-one and 1H-indene-1,2,3-trione and their biological activities such as antibacterial and antifungal activities were studied. In our previous report, new derivatives of spiro[in- doline‐3,4ʹ‐[1,3]dithiine] were synthesized by MgO nanoparticles. 17 In this work, the synthesis of derivatives with MgO nanoparticles was investigated but the desired result was not obtained, that could be due to the larger re- actant material including 11H-indeno[1,2-b]quinoxal- in-11-one than in the previous work. 2. Experimental 2. 1. Chemistry e 1 H and 13 C NMR spectra of compounds in DM- SO-d 6 were measured using a Bruker Ultra Shield-250 spectrometer (250 and 75 MHz, respectively). e FT-IR