Isolation and chemical modifications of parietin from Xanthoria Parietina lichen

Emodin, (1,3,8-trihydroxy-6-methyl-9,10-anthraquinone) is a naturally produced anth-raquinone compound and it is also known, this compound has many bioactive properties like anti-tumor, anti-biotic, anti-viral bioactivities and anti-oxidan. Parietin is a methyla-ted derivative of the 3-hydroxyl position of emodin. Parietin is a secondary metabolite produced in abundance especially by Xanthoria parietina (L.) Th lichen and is known to have antioxidant, antimicrobial antiproliferative and neuroprotective properties. In this study, it is aimed to obtain new biologically active emodic acid derivatives by chemical modifications from parietin, a naturally occurring compound, to obtain bioac-tive natural compounds by chemical modifications, which are very difficult to isolate directly from nature, and to reveal the antioxidant properties of these compounds. Parie-tin was isolated from Xanthoria parietina and chemically modified to reach amino acid and amine conjugated emodic acid derivatives. DPPH method was applied to reveal the antioxidant properties of the obtained compounds. The obtained new amino acid and amine conjugated emodic acid derivatives compounds were characterized by 1D NMR and 2D NMR techniques. Then, the DPPH method was applied to reveal the antioxidant properties of the obtained compounds. As a result, it was seen that a compounds showed moderate antioxidant activity.