TiO2-каталізований синтез первинного аміноноату

HNO induces vascular and myocardial activities, exhibits anticancer and antioxidant activities and inhibits platelet aggregation. However, the mechanism by which it functions is still poorly understood. Primary amine NONOates are HNO donors that can be used to study and understand the chemical properties and physiological effects of HNO. However, its synthesis involves very high pressure and low temperature conditions and requires specialized glassware and equipment. The aim. In this study, a method for the synthesis of an HNO donor, a primary amine NONOate based on cyclohexylamine, that does not involve specialized glassware and high pressure is developed. Materials and methods. The synthesis of primary amine NONOate was performed through the reaction of cyclohexylamine and NO gas, in the presence of sodium methoxide and TiO2, for 24 h. The resulting product was isolated and characterized spectrophotometrically to determine its identity, decomposition kinetics, and HNO release profile at physiological pH. The synthesis method was further optimized based on reaction time, solvent, catalyst loading, and temperature. Results. The TiO2-catalyzed method yielded the desired product which was characterized spectrophotometrically. The product shows typical electronic spectrum of a NONOate (λmax = 250 nm), followed first-order decomposition kinetics, and released both HNO and NO at physiological pH, which are characteristics of primary amine NONOate. The method yielded 5.98 mg cyclohexylamine NONOate which is equivalent to a percent yield of 0.0550%. The yield of the method was low but comparable to the yield from conventional method (1-20%) which requires -78 °C and 50 psi NO. Furthermore, the yield of this method is sufficient for chemical and biological assays. Conclusion. This study proposed a possible alternative method for synthesizing cyclohexylamine NONOate using TiO2 catalysis at ambient conditions. Although the yield is lower than that of conventional method, the result is quite sufficient for chemical and biological assays. This approach eliminates the requirement of using specialized high-pressure and low-temperature equipment, making the study of HNO donors more feasible.