tailieunhanh - Study on chemical constituents of the lichen Parmotrema sancti-angelii (Lynge) Hale. (Parmeliaceae)

Chemical constituent study led to the isolation of three compounds, including methyl β-orcinolcarboxylate (1), salazinic acid (2) and atranorin (3). Their structures were confirmed unambiguously by , spectroscopic data and compared with those in references. This is the first report of salazinic acid distribution in such lichen. | Vietnam Journal of Chemistry, International Edition, 54(4): 524-527, 2016 DOI: Study on chemical constituents of the lichen Parmotrema sancti-angelii (Lynge) Hale. (Parmeliaceae) Nguyen Thi Thu Tram1*, Nguyen Trong Tuan2, Nguyen Phuc Dam2, Nguyen Thi Ngoc Van1, Nguyen Pham Hong Thanh1 1 Department of Chemistry, Faculty of Science, Can Tho University of Medicine and Pharmacy, Vietnam 2 Department of Chemistry, Faculty of Education, Can Tho University, Vietnam Received 31 March 2016; Accepted for publication 12 August 2016 Abstract Lichens are fungal and algal/cyanobacterial symbioses resulting in the production of specific metabolites. Parmotrema sancti-angelii (Lynge) Hale is a lichen which has not been chemically and biologically studied well. From the lichen collected in Vietnam, colour reactions for identification of lichen substances (+K red, +P yellow, -C, +KC red ) suggested the presence of quinones, depsides and xanthones containing two free hydroxyl groups in meta-position, depsides and depsidones containing an aldehyde group. Chemical constituent study led to the isolation of three compounds, including methyl β-orcinolcarboxylate (1), salazinic acid (2) and atranorin (3). Their structures were confirmed unambiguously by X-ray diffraction, spectroscopic data and compared with those in references. This is the first report of salazinic acid distribution in such lichen. Keywords. Parmeliaceae, Parmotrema sancti-angelii, X-ray, NMR, salazinic acid. 1. INTRODUCTION useful lichen reagents (K, C, KC, P). From lichen Parmotrema sancti-angelii, collected in Lam Dong province, Vietnam, three compounds methyl βorcinolcarboxylate (1), salazinic acid (2) and atranorin (3) were isolated by rapid and efficient purification. Although (2) has already been reported for some species of this genus, it is the first report for P. sancti-angelii. Their chemical structures were elucidated by X-rays, NMR spectroscopic data analysis and comparison