Salicine and its derivatives

Salicin je prvi fenolni glukozid pronađen u prirodi, a oralnom primjenom metabolizira u farmakološki aktivni oblik salicilnu kiselinu. Postoji mnogo derivata salicilne kiseline, od kojih je jedan najpoznatiji i najviše korišten lijek, acetilsalicilna kiselina ili Aspirin®. Aspirin je lijek koji ima svojstvo antipiretika i antikoagulanta, a djeluje tako što inhibira aktivnost enzima kao ciklooksigenaze koji dovodi do stvaranja prostaglandina, tvari odgovorne za upalu i bol. Najpoznatija metoda sinteze acetilsalicilne kiseline je esterifikacija salicilne kiseline acetanhidridom uz fosfatnu ili sumpornu kiselinu. Cilj završnog rada bio je ispitati mogućnost sinteze acetilsalicilne kiseline reakcijom esterifikacije salicilne kiseline acetanhidridom konvencionalnom metodom, ali uz uporabu eutektičkih otapala na bazi kolin-klorida (ChCl) za koja se može pretpostaviti katalitička uloga u reakciji esterifikacije. Rezultati eksperimentalnog rada pokazali su da se eutektičko otapalo ChCl: levulinska kiselina i ChCl: limunska kiselina ne mogu koristiti kao katalizator u sintezi acetilsalicilne kiseline. Međutim, uz uporabu eutektičkog otapala ChCl : urea dobivena je acetilsalicilna kiselina pri čemu je po prvi puta potvrđena mogućnost primjene eutektičkih otapala u sintezi acetilsalicilne kiseline.Salicin is the first phenolic glucoside found in nature and after oral use it is metabolized to a pharmacologically active form, salicylic acid. There are many salicylic acid derivatives, one of which is the most commonly used drug, acetylsalicylic acid or aspirin. Aspirin is a medicine that has antipyretic and anticoagulant properties and acts by inhibiting activity of the enzyme cyclooxygenase which is responsible for the production of prostaglandins, substances responsible for inflammation and pain. The most known method of aspirin synthesis is esterification of salicylic acid with acetic anhydride with phosphoric or sulfuric acid. The aim of final thesis was to investigate the possibility of aspirin synthesis by conventional method, but with the use of choline chloride (ChCl) eutectic solvents for which a catalytic role in the esterification reaction can be assumed. The results of the experimental work showed that the eutectic solvents ChCl: levulinic acid and ChCl: citric acid can’t be used as catalyst for the acetylsalicylic acid synthesis. However, with the use of eutectic solvent ChCl: urea, acetylsalicylic acid was obtained and for the first time the possibility of using eutectic solvent in the acetylsalicylic acid synthesis was confirmed