Novel N-phenylcarbamothioylbenzamides with anti-inflammatory activity and prostaglandin E2 inhibitory properties

Abstract

Carmen Limban,1 Alexandru Vasile Missir,1 Khairi Mustafa Salem Fahelelbom,2 Moawia Mohammad Al-Tabakha,2 Miron Teodor Caproiu,3 Bassem Sadek4 1Department of Pharmaceutical Chemistry, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; 2Department of Pharmaceutical Sciences, College of Pharmacy, Al Ain University of Science and Technology, Al Ain, United Arab Emirates; 3Costin D Nenitescu Center of Organic Chemistry Romanian Academy, Bucharest, Romania; 4Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates Abstract: A number of 2-((4-ethylphenoxy)methyl)-N-(substituted-phenylcarbamothioyl)benzamides (1a–h) were synthesized via reaction of 2-((4-ethylphenoxy)methyl)benzoyl isothiocyanate (2) as a key intermediate with several substituted primary aromatic amines. The new compounds were characterized by proton nuclear magnetic resonance (1H-NMR), carbon-13 nuclear magnetic resonance (13C-NMR), infrared spectrometry (IR), mass spectrometry (MS), and elemental analysis. The anti-inflammatory activity of 1a–h was investigated by acute carrageenan-induced paw edema in mice using the reference drug indomethacin. The results obtained indicated that, of the derivatives developed, 1a and 1d–h exhibited significantly higher anti-inflammatory activity (26.81%–61.45%) when compared with the reference drug indomethacin (22.43%) (P = 0.0490 for 1a, 0.0015 for 1d, 0.0330 for 1f, and P 0.05). Moreover, the PGE2 level of 54.15 pg/mL with 1h was also significantly different from that of the placebo group (P > 0.001) and of the indomethacin group (P > 0.05). The significant inhibition of PGE2 observed with 1e (68.32 pg/mL) and 1h (54.15 pg/mL) agree with their observed ulcer incidences. Our overall findings for N-phenylcarbamothioylbenzamides 1a–h clearly suggest that the compounds exhibit an anti-inflammatory effect, potently inhibit PGE2 synthesis, and markedly demonstrate low ulcer incidence. Keywords: PGE2, inhibitory properties, N-phenylcarbamothioylbenzamides, indomethacin, gastric ulcer, ulcerogenic