1 3 J IRAN CHEM SOC DOI 10.1007/s13738-016-1024-6 ORIGINAL PAPER Synthesis of novel 1,8-dioxo octahydroacridine functionalized thioureas and thiazolidinones and evaluation of their antimicrobial activities Arman Shokooh Saljooghi 1 · Hojatollah Khabazzadeh 1 · Moj Khaleghi 2 Received: 9 August 2016 / Accepted: 5 December 2016 © Iranian Chemical Society 2016 Various 1, 3-disubstituted thiourea derivatives are excep- tionally flexible building blocks for the synthesis of a col- lection of heterocyclic compounds and exhibit a wide range of biological activities. Many thiourea derivatives exhibited remarkable antimicrobial activities [8]; 1, 3-dialkyl or dia- ryl thiourea derivatives showed significant antifungal activ- ity against plant pathogens [9]. Experimental All chemicals purchased from Merck chemical company and used without further purification. 1 H NMR and 13 C NMR spectra were recorded on a Bruker Ultrashield-400 NMR spectrometer using DMSO- d 6 as a solvent. IR spectra were recorded on a Bruker Tensor-27 FT-IR spectrophotometer using KBr pellets. Melting points were measured on an Electrothermal-9100 apparatus. Elemental analyses were run on a LECO-932 series. Synthesis of 1-(4-Amino-phenyl)-3-methyl-thiourea 1 A mixture of 1, 4-phenylene diamine (10 mmol) and methyl isothiocyanate (10 mmol) in 20 mL ethanol was heated at 60 °C. The promotion of the reaction was moni- tored by TLC. When the reaction was completed (90 min), the solvent was vaporized and remaining solid was washed with the mixture of hexane/ethyl acetate (9:1). The resultant precipitate was filtered and dried. After that, the precipitate was dissolved in 20% HCl solution and filtered. Then, 10% NaOH solution was added to the fil- tered solution until pH 7–8 was obtained and 1-(4-Amino- phenyl)-3-methyl-thiourea 1 as a white precipitate was separated. Abstract New series of thiourea and thiazolidinone deriv- atives containing a 1,8-dioxo octahydroacridinyl moiety have been synthesized through the reaction of 1-(4-Amino- phenyl)-3-methyl-thiourea with various aromatic aldehydes and dimedone. All the synthesized compounds were tested against several microbial pathogens Staphylococcus aureus, Micrococcus luteus, Escherichia coli, Pseudomonas aerug- inosa, Klebsiella pneumoniae and Candida albicans. Keywords Thiourea · Thiazolidinone · 1,8-Dioxo octahydroacridine · Dialkyl acetylenedicarboxylate · Antimicrobial Introduction One of the important heterocyclic systems that exists in biologically active compounds is thiazole ring. Thiazoles are present in many biologically active molecules such as antimicrobial drugs (sulfathiazole and penicillin) [1]. Acridine derivatives are another important heterocyclic structures having antimalarial, antiviral and antiallergic properties [2–4]; acridines act as powerful drugs for anti- tumor activity both in vitro and in vivo against some of rat and human tumors [5]. Some of fluorinated acridones were announced to have anticancer activity [6, 7]. * Hojatollah Khabazzadeh hkhabazzadeh@uk.ac.ir 1 Department of Chemistry, Shahid Bahonar University of Kerman, Kerman 7616914111, Iran 2 Department of Biology, Shahid Bahonar University of Kerman, Kerman 7616914111, Iran