and P.-C.K.; WritingOriginal Draft, Y.-C.L.; WritingCReview & Editing, S.-H.L., P.-C.K., and J.T.C.T. to on superoxide anion era and elastase discharge by individual neutrophils in response to 0.05, *** 0.001 weighed against the control value (DMSO). 2. Discussion and Results 2.1. Characterization and Purification The whole-plants of had been air-dried, powdered, and extracted with methanol under reflux. The methanol extract was focused under decrease pressure to provide a deep dark brown syrup extract. This remove was partitioned with drinking water and chloroform to supply two soluble levels, i.e., chloroform drinking water and soluble soluble levels, respectively. With the help of a combined mix of typical chromatographic methods, one sesquiterpenoid viglutin (1), one alkaloid viglutoside (2), one -pyranone viglutanone (3), along with two salts sodium phaseate (4) and sodium p-coumarate (5), had been characterized and their buildings were made of the nuclear magnetic resonance (NMR) spectral elucidation and mass (MS) spectrometric evaluation. Furthermore, sixty-eight known substances, including eight sesquiterpenoids, loliolide (6), isololiolide (7), blumenol A (8), kiwiionol (9), (+)-(249.1460 in high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) evaluation. The infrared (IR) absorption rings at 3416 and 1647 cm?1 were in contract using the presences of hydroxy and carbonCcarbon increase connection functionalities, respectively. In the 1H-NMR range, there have been proton indicators for just two methyl singlets at 0.96 (3H, s, CH3-11), 1.06 (3H, s, CH3-12), one methyl doublet of doublets 1.73 (3H, dd, = 6.5, 1.5 Hz, CH3-10), two oxymethylene protons at 3.61 (1H, dd, = 11.0, 7.0 Hz, H-13a) and 3.81 (1H, m, H-13b), two oxymethine at 3.80 (1H, dddd, = 12.0, 7.5, 5.0, 3.5 Hz, H-3) and 4.18 (1H, d, = 8.5 Hz, H-7), three methines at 1.36 (1H, ddd, = 12.6, 5.0, 1.5 Hz, H-2b), 1.51 (1H, ddd, = 12.0, 12.0, 11.5 Hz, H-4a), 2.44 (1H, m, H-5), and two trans olefinic protons at 5.67 (1H, ddd, = 15.5, 8.5, 1.5 Hz, H-8) and 5.78 (1H, dq, = 15.5, 6.5 Hz, H-9). The 13C-NMR and distortionless improvement by polarization transfer (DEPT) spectra exhibited three methyl carbons at 18.2 (C-10), 24.0 (C-12) and 25.9 (C-11); three methylene carbons at 31.6 (C-4), 46.8 (C-2), and 69.7 (C-13); five methines at 43.7 (C-5), 68.5 (C-3), 84.4 (C-7), 129.6 (C-8), and 132.1 (C-9); and two quaternary carbons at 37.7 (C-1) and 81.2 (C-6). The relationship spectroscopy (COSY) indicated the linkage of H-2/H-3/H-4/H-5/H-13 and H-7/H-8/H-9/H-10 (Amount 1). The 2294.0952, calc. for C12H17NNaO6, 294.0954). The UV absorption maxima at 274 and 221 nm had been indication from the heteroaromatic chromophore [38], and it had been supported with the downfield ABX-coupled aromatic protons at 7 further.21 (1H, dd, = 8.5, 2.5 Hz, H-4), 7.32 (1H, d, = 8.5 Hz, H-5), and 8.03 (1H, d, = 2.5 Hz, H-2). The life of hydroxyl and carbonCcarbon dual bond functionalities could possibly be determined in the IR absorption rings at 3430 and 1637 cm?1. One methylene group at 4.51 (1H, d, = 12.0 Hz, H-7a) and 4.65 (1H, d, = 12.0 Hz, H-7b), and one group of rhamnose protons at 1.25 (3H, d, = 6.0 Hz, H-6), 3.38 (1H, dd, = 9.5, 9.5 Hz, H-4), 3.60 (1H, dd, = 9.5, 6.0 Hz, H-5), 3.67 (1H, dd, = 9.5, 3.5 Hz, H-3), 3.85 (1H, dd, = 3.5, 2.0 Hz, H-2), and 4.78 (1H, d, = 2.0 Hz, H-1) made an appearance in the 1H-NMR spectral range of 2. In its 13C-NMR range, a couple of indicators at 18.0 (C-6), 70.1 (C-5), 72.3 (C-2), 72.4 (C-3), 74.0 (C-4), and 101.4 (C-1) also evidenced the current presence of rhamnoside [39]. The noticed HMBC correlations from H-2 to C-3, C-4, and C-6; from H-4 to C-6; from H-5 to C-6 and C-3; from H-7 to C-5, C-6, and C-1; from H-1 to C-5 and C-3, respectively, set up the framework of 2 as 6-(-rhamnosyloxymethyl)-3-pyridinol (Amount 2) and designated the trivial name as viglutoside. Open up in another window Amount 2 Essential COSY (?) and HMBC () correlations of 2 and 3. Viglutanone (3) was isolated as dark brown syrup, as well as the molecular formulation was driven as.Louis, MO, USA). 0.001 weighed against the control value (DMSO). 2. Outcomes and Debate 2.1. Purification and Characterization The whole-plants of had been air-dried, powdered, and extracted with methanol under reflux. The methanol extract was focused under decrease pressure to provide a deep dark brown syrup extract. This remove was partitioned with drinking water and chloroform to supply two soluble levels, i actually.e., chloroform soluble and drinking water soluble levels, respectively. With the help of a combined mix of typical chromatographic methods, one sesquiterpenoid viglutin (1), one alkaloid viglutoside (2), one -pyranone viglutanone (3), along with two salts sodium phaseate (4) and sodium p-coumarate (5), had been characterized and their buildings were made of the nuclear magnetic resonance (NMR) spectral elucidation and mass (MS) spectrometric evaluation. Furthermore, sixty-eight known substances, including eight sesquiterpenoids, loliolide (6), isololiolide (7), blumenol A (8), kiwiionol (9), (+)-(249.1460 in high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) evaluation. The infrared (IR) absorption rings at 3416 and 1647 cm?1 were in contract using the presences of hydroxy and carbonCcarbon increase connection functionalities, respectively. In the 1H-NMR range, there have been proton indicators for just two methyl singlets at 0.96 (3H, s, CH3-11), 1.06 (3H, s, CH3-12), one methyl doublet of doublets 1.73 (3H, dd, = 6.5, 1.5 Hz, CH3-10), two oxymethylene protons at 3.61 (1H, dd, = 11.0, 7.0 Hz, H-13a) and 3.81 (1H, m, H-13b), two oxymethine at 3.80 (1H, dddd, = 12.0, 7.5, 5.0, 3.5 Hz, H-3) and 4.18 (1H, d, = 8.5 Hz, H-7), three methines at 1.36 (1H, ddd, = 12.6, 5.0, 1.5 Hz, H-2b), 1.51 (1H, ddd, = 12.0, 12.0, 11.5 Hz, H-4a), 2.44 (1H, m, H-5), and two trans olefinic protons at 5.67 (1H, ddd, = 15.5, 8.5, 1.5 Hz, H-8) and 5.78 (1H, dq, = 15.5, 6.5 Hz, H-9). The 13C-NMR and distortionless improvement by polarization transfer (DEPT) spectra exhibited three methyl carbons at 18.2 (C-10), 24.0 (C-12) and 25.9 (C-11); three methylene carbons at 31.6 (C-4), 46.8 (C-2), and 69.7 (C-13); five methines at 43.7 (C-5), 68.5 (C-3), 84.4 (C-7), 129.6 (C-8), and 132.1 (C-9); and two quaternary carbons JK 184 at 37.7 (C-1) and 81.2 (C-6). The relationship spectroscopy (COSY) indicated the linkage of H-2/H-3/H-4/H-5/H-13 and H-7/H-8/H-9/H-10 (Amount 1). The 2294.0952, calc. for C12H17NNaO6, 294.0954). The UV absorption maxima at 274 and 221 nm had been indication from the heteroaromatic chromophore [38], and it had been further supported with the downfield ABX-coupled aromatic protons at 7.21 (1H, dd, = 8.5, 2.5 Hz, H-4), 7.32 (1H, d, = 8.5 Hz, H-5), and 8.03 (1H, d, = 2.5 Hz, H-2). The life of hydroxyl and carbonCcarbon dual bond functionalities could possibly be determined in the IR absorption rings at 3430 and 1637 cm?1. One methylene group at 4.51 (1H, d, = 12.0 Hz, H-7a) and 4.65 (1H, d, = 12.0 Hz, H-7b), and one group of rhamnose protons at 1.25 (3H, d, = 6.0 Hz, H-6), 3.38 (1H, dd, = 9.5, 9.5 Hz, H-4), 3.60 (1H, dd, = 9.5, 6.0 Hz, H-5), 3.67 (1H, dd, = 9.5, 3.5 Hz, H-3), 3.85 (1H, dd, = 3.5, 2.0 Hz, H-2), and 4.78 (1H, d, = 2.0 Hz, H-1) made an appearance in the 1H-NMR spectral range of 2. In its 13C-NMR range, a couple of indicators at 18.0 (C-6), 70.1 (C-5), 72.3 (C-2), 72.4 (C-3), 74.0 (C-4), and 101.4 (C-1) also evidenced the current presence of rhamnoside [39]. The noticed HMBC correlations from H-2 to C-3, C-4, and C-6; from H-4 to C-6; from H-5 to C-3 and C-6; from H-7 to C-5, C-6, and C-1; from H-1 to C-3 and C-5, respectively, set up the framework of 2 as 6-(-rhamnosyloxymethyl)-3-pyridinol (Amount 2) and designated the trivial name as viglutoside. Open up in another window Amount 2 Essential COSY (?) and HMBC () correlations of 2 and 3. Viglutanone (3) was isolated as dark brown syrup, as well as the molecular formulation was driven as C9H10O5 with a deprotonated molecular ion top.Likened the spectral data of 5 with those of species shown significant chemoprevention potentials. to provide a deep dark brown syrup remove. This remove was partitioned with drinking water and chloroform to supply two soluble levels, i actually.e., chloroform soluble and drinking water soluble levels, respectively. With the help of a combined mix of typical chromatographic methods, one sesquiterpenoid viglutin (1), one alkaloid viglutoside (2), one -pyranone viglutanone (3), along with two salts sodium phaseate (4) and sodium p-coumarate (5), had been characterized and their buildings were made of the nuclear magnetic resonance (NMR) spectral elucidation and mass (MS) spectrometric evaluation. Furthermore, sixty-eight known substances, including eight sesquiterpenoids, loliolide (6), isololiolide (7), blumenol A (8), kiwiionol (9), (+)-(249.1460 in high-resolution electrospray ionization JK 184 mass spectrometry (HR-ESI-MS) evaluation. The infrared (IR) absorption rings at 3416 and 1647 cm?1 were in contract using the presences of hydroxy and carbonCcarbon increase connection functionalities, respectively. In the 1H-NMR range, there have been proton indicators for just two methyl singlets at 0.96 (3H, s, CH3-11), 1.06 (3H, s, CH3-12), one methyl doublet of doublets 1.73 (3H, dd, = 6.5, 1.5 Hz, CH3-10), two oxymethylene protons at 3.61 (1H, dd, = 11.0, 7.0 Hz, H-13a) and 3.81 (1H, m, H-13b), two oxymethine at 3.80 (1H, dddd, = 12.0, 7.5, 5.0, 3.5 Hz, H-3) and 4.18 (1H, d, = 8.5 Hz, H-7), three methines at 1.36 (1H, ddd, = 12.6, 5.0, 1.5 Hz, H-2b), 1.51 (1H, ddd, = 12.0, 12.0, 11.5 Hz, H-4a), 2.44 (1H, m, H-5), and two trans olefinic protons at 5.67 (1H, ddd, = 15.5, 8.5, 1.5 Hz, H-8) and 5.78 (1H, dq, = 15.5, 6.5 Hz, H-9). The 13C-NMR and distortionless improvement by polarization transfer (DEPT) spectra exhibited three methyl carbons at 18.2 (C-10), 24.0 (C-12) and 25.9 (C-11); three methylene carbons at 31.6 (C-4), 46.8 (C-2), and 69.7 (C-13); five methines at 43.7 (C-5), 68.5 (C-3), 84.4 (C-7), 129.6 (C-8), and 132.1 (C-9); and two quaternary carbons at 37.7 (C-1) and 81.2 (C-6). The relationship spectroscopy (COSY) indicated the linkage of H-2/H-3/H-4/H-5/H-13 and H-7/H-8/H-9/H-10 (Body 1). The 2294.0952, calc. for C12H17NNaO6, 294.0954). The UV absorption maxima at 274 and 221 nm had been indication from the heteroaromatic chromophore [38], and it had been further supported with the downfield ABX-coupled aromatic protons at 7.21 (1H, dd, = 8.5, 2.5 Hz, H-4), 7.32 (1H, d, = 8.5 Hz, H-5), and 8.03 (1H, d, = 2.5 Hz, H-2). The lifetime of hydroxyl and carbonCcarbon dual bond functionalities could possibly be determined in the IR absorption rings at 3430 and 1637 cm?1. One methylene group at 4.51 (1H, d, = 12.0 Hz, H-7a) and 4.65 (1H, d, = 12.0 Hz, H-7b), and one group of rhamnose protons at 1.25 (3H, d, = 6.0 Hz, H-6), 3.38 (1H, dd, = 9.5, 9.5 Hz, H-4), 3.60 (1H, dd, = 9.5, 6.0 Hz, H-5), 3.67 (1H, dd, = 9.5, 3.5 Hz, H-3), 3.85 (1H, dd, = 3.5, 2.0 Hz, H-2), and 4.78 (1H, d, = 2.0 Hz, H-1) made an appearance in the 1H-NMR spectral range of 2. In its 13C-NMR range, a couple of indicators at 18.0 (C-6), 70.1 (C-5), 72.3 (C-2), 72.4 (C-3), 74.0 (C-4), and 101.4 (C-1) also evidenced the current presence of rhamnoside [39]. The noticed HMBC correlations from H-2 to C-3, C-4, and C-6; from H-4 to C-6; from H-5 to C-3 and C-6; from H-7 to C-5, C-6, and C-1; from H-1 to C-3 and C-5, respectively, set up the framework of 2 as 6-(-rhamnosyloxymethyl)-3-pyridinol (Body 2) and designated the trivial name as viglutoside. Open up in another window Body 2 Essential COSY (?) and HMBC () correlations of 2 and 3. Viglutanone (3) was isolated as dark brown syrup, as well as the molecular formulation was motivated as C9H10O5 with a deprotonated molecular ion top at 197.0449 in the HR-ESI-MS analysis..and J.T.C.T.; Data Investigation and Curation, S.-H.L., Y.-C.L., and M.-L.Con.; Technique, T.-L.H. Debate 2.1. Purification and Characterization The whole-plants of had been air-dried, powdered, and extracted with methanol under reflux. The methanol extract was focused under decrease pressure to provide a deep dark brown syrup extract. This remove was partitioned with drinking water and chloroform to supply two soluble levels, i actually.e., chloroform soluble and drinking water soluble levels, respectively. With the help of a combined mix of typical chromatographic methods, one sesquiterpenoid viglutin (1), one alkaloid viglutoside (2), one -pyranone viglutanone (3), along with two salts sodium phaseate (4) and sodium p-coumarate (5), had been characterized and their buildings were made of the nuclear magnetic resonance (NMR) spectral elucidation and mass (MS) spectrometric evaluation. Furthermore, sixty-eight known substances, including eight sesquiterpenoids, loliolide (6), isololiolide (7), blumenol A (8), kiwiionol (9), (+)-(249.1460 in high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) evaluation. The infrared (IR) absorption rings at 3416 and 1647 cm?1 were in contract using the presences of hydroxy and carbonCcarbon increase connection functionalities, respectively. In the 1H-NMR range, there have been proton indicators for just two methyl singlets at 0.96 (3H, s, CH3-11), 1.06 (3H, s, CH3-12), one methyl doublet of doublets 1.73 (3H, dd, = 6.5, 1.5 Hz, CH3-10), two oxymethylene protons at 3.61 (1H, dd, = 11.0, 7.0 Hz, H-13a) and 3.81 (1H, m, H-13b), two oxymethine at 3.80 (1H, dddd, = 12.0, 7.5, 5.0, 3.5 Hz, H-3) and 4.18 (1H, d, = 8.5 Hz, H-7), three methines at 1.36 (1H, ddd, = 12.6, 5.0, 1.5 Hz, H-2b), 1.51 (1H, ddd, = 12.0, 12.0, 11.5 Hz, H-4a), 2.44 (1H, m, H-5), and two trans olefinic protons at 5.67 (1H, ddd, = 15.5, 8.5, 1.5 Hz, H-8) and 5.78 (1H, dq, = 15.5, 6.5 Hz, H-9). The 13C-NMR and distortionless improvement by polarization transfer (DEPT) spectra exhibited three methyl carbons at 18.2 (C-10), 24.0 (C-12) and 25.9 (C-11); three methylene carbons at 31.6 (C-4), 46.8 (C-2), and 69.7 (C-13); five methines at 43.7 (C-5), 68.5 (C-3), 84.4 (C-7), 129.6 (C-8), and 132.1 (C-9); and two quaternary carbons at 37.7 (C-1) and 81.2 (C-6). The relationship spectroscopy (COSY) indicated the linkage of H-2/H-3/H-4/H-5/H-13 and H-7/H-8/H-9/H-10 (Body 1). The 2294.0952, calc. for C12H17NNaO6, 294.0954). The UV absorption maxima at 274 and 221 nm had been indication from the heteroaromatic chromophore [38], and it had been further supported with the downfield ABX-coupled aromatic protons at 7.21 (1H, dd, = 8.5, 2.5 Hz, H-4), 7.32 (1H, d, = 8.5 Hz, H-5), and 8.03 (1H, d, = 2.5 Hz, H-2). The lifetime of hydroxyl and carbonCcarbon dual bond functionalities could possibly be determined in the IR absorption rings at 3430 and 1637 cm?1. One methylene group at 4.51 (1H, d, = 12.0 Hz, H-7a) and 4.65 (1H, d, = 12.0 Hz, H-7b), and one group of rhamnose protons at 1.25 (3H, d, = 6.0 Hz, H-6), 3.38 (1H, dd, = 9.5, 9.5 Hz, H-4), 3.60 (1H, dd, = 9.5, 6.0 Hz, H-5), 3.67 (1H, dd, = 9.5, 3.5 Hz, H-3), 3.85 (1H, dd, = 3.5, 2.0 Hz, H-2), and 4.78 (1H, d, = 2.0 Hz, H-1) made an appearance in the 1H-NMR spectral range of 2. In its 13C-NMR range, a couple of indicators at 18.0 (C-6), 70.1 (C-5), 72.3 (C-2), 72.4 (C-3), 74.0 (C-4), and 101.4 (C-1) also evidenced the current presence of rhamnoside [39]. The noticed HMBC correlations from H-2 to C-3, C-4, and C-6; from H-4 to C-6; from H-5 to C-3 and C-6; from H-7 to C-5, C-6, and C-1; from H-1 to C-3 and C-5, respectively, set up the framework of 2 as 6-(-rhamnosyloxymethyl)-3-pyridinol (Body BPES1 2) and designated the trivial name as viglutoside. Open up in another window Body 2 Essential COSY (?) and HMBC () correlations of 2 and 3. Viglutanone (3) was isolated as dark brown syrup, as well as the molecular formulation was motivated as C9H10O5 with a deprotonated molecular ion top at 197.0449 in the HR-ESI-MS analysis. The UV absorption optimum at 299 IR and nm absorption rings at 3493, 1703, and 1631 cm?1, combined with the factor of IHD worth (5) proposed the current presence of an -pyranone simple structure using a carboxylic acidity group. It had been further evidenced with the proton indicators for just two vinyl fabric singlets at 6.25 (1H, H-3) and 6.97 (1H, H-5) in 1H-NMR, as well as the carbon peaks for just two vinyl groupings at 110.4 (C-5), 114.8 (C-3), 156.4 (C-6),.Column chromatography was performed on silica gels in various mesh sizes (70C230 and 230C400 mesh, Kieselgel 60, Merck KGaA, Darmstadt, Germany). under decrease pressure to provide a deep dark brown syrup remove. This remove was partitioned with drinking water and chloroform to supply two soluble levels, i actually.e., chloroform soluble and drinking water soluble levels, respectively. With the help of a combined mix of typical chromatographic methods, one sesquiterpenoid viglutin (1), one alkaloid viglutoside (2), one -pyranone viglutanone (3), along with two salts sodium phaseate (4) and sodium p-coumarate (5), had been characterized and their buildings were made of the nuclear magnetic resonance (NMR) spectral elucidation and mass (MS) spectrometric evaluation. Furthermore, sixty-eight known substances, including eight sesquiterpenoids, loliolide (6), isololiolide (7), blumenol A (8), kiwiionol (9), (+)-(249.1460 in high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) evaluation. The infrared (IR) absorption rings at 3416 and 1647 cm?1 were in contract using the presences of hydroxy and carbonCcarbon increase connection functionalities, respectively. In the 1H-NMR range, there have been proton indicators for just two methyl singlets at 0.96 (3H, s, CH3-11), 1.06 (3H, s, CH3-12), one methyl doublet of doublets 1.73 (3H, dd, = 6.5, 1.5 Hz, CH3-10), two oxymethylene protons at 3.61 (1H, dd, = 11.0, 7.0 Hz, H-13a) and 3.81 (1H, m, H-13b), two oxymethine at 3.80 (1H, dddd, = 12.0, 7.5, 5.0, 3.5 Hz, H-3) and 4.18 (1H, d, = 8.5 Hz, H-7), three methines at 1.36 (1H, ddd, = 12.6, 5.0, 1.5 Hz, H-2b), 1.51 (1H, ddd, = 12.0, JK 184 12.0, 11.5 Hz, H-4a), 2.44 (1H, m, H-5), and two trans olefinic protons at 5.67 (1H, ddd, = 15.5, 8.5, 1.5 Hz, H-8) and 5.78 (1H, dq, = 15.5, 6.5 Hz, H-9). The 13C-NMR and distortionless improvement by polarization transfer (DEPT) spectra exhibited three methyl carbons at 18.2 (C-10), 24.0 (C-12) and 25.9 (C-11); three methylene carbons at 31.6 (C-4), 46.8 (C-2), and 69.7 (C-13); five methines at 43.7 (C-5), 68.5 (C-3), 84.4 (C-7), 129.6 (C-8), and 132.1 (C-9); and two quaternary carbons at 37.7 (C-1) and 81.2 (C-6). The relationship spectroscopy (COSY) indicated the linkage of H-2/H-3/H-4/H-5/H-13 and H-7/H-8/H-9/H-10 (Body 1). The 2294.0952, calc. for C12H17NNaO6, 294.0954). The UV absorption maxima at 274 and 221 nm had been indication from the heteroaromatic chromophore [38], and it had been further supported with the downfield ABX-coupled aromatic protons at 7.21 (1H, dd, = 8.5, 2.5 Hz, H-4), 7.32 (1H, d, = 8.5 Hz, H-5), and 8.03 (1H, d, = 2.5 Hz, H-2). The lifetime of hydroxyl and carbonCcarbon dual bond functionalities could possibly be determined in the IR absorption rings at 3430 and 1637 cm?1. One methylene group at 4.51 (1H, d, = 12.0 Hz, H-7a) and 4.65 (1H, d, = 12.0 Hz, H-7b), and one group of rhamnose protons at 1.25 (3H, d, = 6.0 Hz, H-6), 3.38 (1H, dd, = 9.5, 9.5 Hz, H-4), 3.60 (1H, dd, = 9.5, 6.0 Hz, H-5), 3.67 (1H, dd, = 9.5, 3.5 Hz, H-3), 3.85 (1H, dd, = 3.5, 2.0 Hz, H-2), and 4.78 (1H, d, = 2.0 Hz, H-1) made an appearance in the 1H-NMR spectral range of 2. In its 13C-NMR range, a couple of indicators at 18.0 (C-6), 70.1 (C-5), 72.3 (C-2), 72.4 (C-3), 74.0 (C-4), and 101.4 (C-1) also evidenced the current presence of rhamnoside [39]. The noticed HMBC correlations from H-2 to C-3, C-4, and C-6; from H-4 to C-6; from H-5 to C-3 and C-6; from H-7 to C-5, C-6, and C-1; from H-1 to C-3 and C-5, respectively, set up the framework of 2 as 6-(-rhamnosyloxymethyl)-3-pyridinol (Figure 2) and assigned the trivial name as viglutoside. Open in a separate window Figure 2 Key COSY (?) and HMBC () correlations of 2 and 3. Viglutanone (3) was isolated as brown syrup, and the molecular formula was determined as C9H10O5 by a deprotonated molecular ion peak at 197.0449 in the HR-ESI-MS analysis. The UV absorption maximum at 299 nm and IR absorption bands at 3493, 1703, and 1631 cm?1, along with the consideration of IHD value (5) proposed the presence of an -pyranone basic structure with a carboxylic acid group. It was further evidenced by the proton signals for two vinyl singlets at 6.25 (1H, H-3) and 6.97 (1H, H-5) in 1H-NMR, and the carbon peaks for two vinyl groups at 110.4 (C-5),.
and P
