SINTESIS SENYAWA ASAM O-(4-FLUOROBENZOIL)-5-METILSALISILAT DAN UJI AKTIVITAS ANALGESIK PADA MENCIT (Mus musculus)

Background: O-(4-Fluorobenzoyl)-5-methylsalicylic acid is a derivative of salicylic acid resulting from the synthesis of 5-methylsalicylic acid and 4-fluorobenzoyl chloride with esterification of acyl halide method. Objective: Produce O-(4-fluorobenzoyl)-5-methylsalicylic of the reaction process between 5-methylsalicylic acid and 4-fluorobenzoyl chloride and to determine analgesics activity in mice. Method: The synthesis is using esterification method of acyl halide, while the analgesic activity test using stretching method (Writhing test). Result: The result obtained from synthesis is crystalline, white, odorless with a percentage 35,09%, with a melting point 172-174oC. TLC test results obtained 1 stain using eluent Chloroform:Methanol (7:3), n-Hexane: Ethyl acetate (6:4), and Aceton: Methanol (7:3). Identification of structure with the UV Spectrophotometer showed the wavelengths 202 nm and 228 nm. IR spectrophotometer showed the wave number 3453,72 cm-1 (-OH); 2852,73 cm-1 (CH3); 1683,63cm-1 dan 1605,67 cm-1 (C=O); 1431,71 cm-1 (C=C); 1295,70 cm-1 (COOC). The H-NMR specthrometer showed 11 H atoms. The percentage of pai inhibition for dose 25 mg/kgBB = 38,71%, 50 mg/kgBB = 54,59%, 100 mg/kgBB = 66,29%. The O-(4-fluorobenzoyl)-5-methylsalicylic acid has ED50 of 42,66 mg/kgBB while Aspirin which is the salicylic acid derivate had ED50 of 134,90 mg/kgBB. Conclusions: The O-(4-fluorobenzoyl)-5-methylsalicylic acid was synthesized and higher activity than Aspirin