Compounds 43a and 43b (Figure 9), obtained by the authors, acted as inhibitors of fatty-acid amide hydrolase 1 (IC50 = 0.035 μM and 0.02 μM, respectively), and in this aspect these derivatives can be useful in the treatment of pain and other FAAH-mediated diseases, and disorders like osteoarthritis, rheumatoid arthritis, diabetic neuropathy, postherpetic neuralgia, fibromyalgia, migraine, sleep disorder, Alzheimer’s disease and Parkinson’s disease. This evidence concerns the gene FAAH and rheumatoid arthritis.