Synthesis and biological evaluation of new benzo-thieno[3,2-d]pyrimidin-4- one sulphonamide thio-derivatives as potential selective cyclooxygenase-2 inhibitors

The aim of this work was to evaluate the potential anti-inflammatory activity of eleven (5-15) new synthesized derivatives of benzo-thieno[3,2-d]pyrimidine on two cell models, namely human keratinocytes NCTC 2544 and mouse monocyte-macrophages J774. For the synthesis of test compounds an efficient approach was developed: the key isothiocyanate was prepared through a simple and ecological method using di-2-pyridyl thionocarbonate (DPT) in substitution of thiophosgene, a highly toxic agent, and the cyclization reaction of benzo-thiosemicarbazide derivates was performed through Wamhoff methods. This procedure can be a new alternative method economically and environmentally advantageous by the simplicity of procedure, reduction of isolation and purification steps, time, costs, and waste production. The potential anti-inflammatory activity of 5-15 was evaluated by determining the expression of cyclooxygenase (COX)-2, inducible NO synthase (iNOS), and intercellular adhesion molecule-1 (ICAM-1), and the release of prostaglandins (PG)E and interleukin-8 (IL-8). Our results demonstrate that the compounds 7, 10, 12, 13, 14, and 15 act as a potent inhibitor of COX-2, iNOS, ICAM-1 expression while also suppressing the production of PGE and IL-8 in human keratinocytes NCTC 2544 exposed to interferon-gamma (IFN-) and histamine and monocyte-macrophages J774 cells treated with lipopolysaccharides (LPS). In conclusion, some derivatives of benzo-thieno[3,2-d]pyrimidine could be developed as a novel class of anti-inflammatory agents.