Cite this paper: Vietnam J. Chem., 2019, 57(1), 64-69 Article DOI: 10.1002/vjch.201960010 64 Wiley Online Library© 2019 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Quinovic acid glycosides from Mussaenda pilosissima Valeton Nguyen Xuan Bach 2,3 , Vu Kim Thu 1 , Do Thi Trang 2 , Phan Van Kiem 2,3* 1 Hanoi University of Mining and Geology, Viet Nam 2 Institute of Marine Biochemistry, Vietnam Academy of Science and Technology (VAST), Viet Nam 3 Graduate University of Science and Technology, VAST, Viet Nam Received December 18, 2018; Accepted for publication January 5, 2019 Abstract Four known quinovic acid glycosides, quinovic acid 28-O-β-D-glucopyranosyl ester (1), 3-O-α-L- rhamnopyranosylquinovic acid 28-O-β-D-glucopyranosyl ester (glycoside A, 2), and 3-O-β-D-glucopyranosylquinovic acid 28-O-β-D-glucopyranosyl ester (glycoside B, 3), 3-O-α-L-rhamnopyranosylquinovic acid 28-O-β-D-glucopyranosyl ester (4) were isolated from the aerial parts of Mussaenda pilosissima Valeton. Their chemical structures were determined using NMR spectra as well as in comparison with the reported data. Compounds 1, 2, and 4 were reported for the first time from Mussaenda genus. Keywords. Mussaenda pilosissima, quinovic acid glycoside, ursane. 1. INTRODUCTION The genus Mussaenda comprises about 200 species belonging to the Rubiaceae family. [1] In Vietnam, there are about 27 species of genus Mussaenda. [2] Of which, there are 11 species have been used as folk medicines. [3] The chemical studies of Mussaenda genus indicated the presence of iridoids, triterpenoids, and flavonoids. These compounds have shown the potential significant biological effects as anti-inflammatory, antioxidant, and anticancer activities. [4] Mussaenda pilosissima has been used for the treatment of kidney diseases and blood in urine. [5] Up to now, the chemical constituents of this plant have not been studied yet. Herein, we report the isolation and structural elucidation of four quinovic acid glycosides from the aerial parts Mussaenda pilosissima. 2. MATERIAL AND METHODS 2.1. Plant Material The aerial parts of Mussaenda pilosissima Valeton. were collected at Me Linh, Vinh Phuc, Vietnam in February 2017 and identified by Dr. Nguyen The Cuong, Institute of Ecology and Biological Resources, VAST. A voucher specimen (NCCT- P69) was deposited at the Institute of Marine Biochemistry, VAST. 2.2. General experimental procedures All NMR spectra were recorded on a Bruker AM500 FT-NMR spectrometer (500 MHz for 1 H-NMR and 125 MHz for 13 C-NMR). NMR measurements, including 1 H-, 13 C-NMR, HSQC, and HMBC experiments, were carried out using 5-mm probe tubes at temperature of 22.2 o C. ESI mass spectra were recorded on an Agilent 6530 Accurate-Mass Q- TOF LC/MS system. Column chromatography was performed using a silica gel (Kieselgel 60, 70-230 mesh and 230-400 mesh, Merck) or RP-18 resins (150 μm, Fuji Silysia Chemical Ltd.), thin layer chromatography (TLC) using a pre-coated silica-gel 60 F254 (0.25 mm, Merck) and RP-18 F254S plates (0.25 mm, Merck). 2.3. Extraction and isolation The dried powder of aerial parts of M. pilosissima Valeton. (4.2 kg) was sonicated 3 times with hot methanol. The extract was filtered through filter paper, then solvent was removed under reduced pressure to yield 320 g of a dark solid extract. The extract was suspended in water and successively partitioned with n-hexane, dichloromethane, ethyl acetate giving n-hexane (MPA1 56.8 g), dichloromethane (MPA2 97.8 g), ethyl acetate extracts (MPA3 23 g) and water layer (MPA4).