DSpace at VNU: A new guaianolide fromArtemisia roxburghiana

This article was downloaded by: [Aston University] On: 04 September 2014, At: 08:09 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Natural Product Research: Formerly Natural Product Letters Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/gnpl20 A new guaianolide from Artemisia roxburghiana a a a Phan Minh Giang , Tran Thi Thanh Nhan , Phan Tong Son , b Katsuyoshi Matsunami & Hideaki Otsuka b a Faculty of Chemistry, VNU University of Science, Vietnam National University, 19 Le Thanh Tong Street, Hanoi, Vietnam b Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan Published online: 22 Feb 2013 To cite this article: Phan Minh Giang, Tran Thi Thanh Nhan, Phan Tong Son, Katsuyoshi Matsunami & Hideaki Otsuka (2013) A new guaianolide from Artemisia roxburghiana, Natural Product Research: Formerly Natural Product Letters, 27:20, 1856-1858, DOI: 10.1080/14786419.2013.768991 To link to this article: http://dx.doi.org/10.1080/14786419.2013.768991 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content This article may be used for research, teaching, and private study purposes Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden Terms & Downloaded by [Aston University] at 08:09 04 September 2014 Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions Natural Product Research, 2013 Vol 27, No 20, 1856–1858, http://dx.doi.org/10.1080/14786419.2013.768991 A new guaianolide from Artemisia roxburghiana Phan Minh Gianga*, Tran Thi Thanh Nhana, Phan Tong Sona, Katsuyoshi Matsunamib and Hideaki Otsukab a Faculty of Chemistry, VNU University of Science, Vietnam National University, 19 Le Thanh Tong Street, Hanoi, Vietnam; bGraduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8553, Japan Downloaded by [Aston University] at 08:09 04 September 2014 (Received 11 October 2012; final version received 25 December 2012) A new member of 5a H,6b H,7a H,11a H-guaian-12,6a-olides, 11-epi-8a-hydroxyarborescin, together with a mixture of (24R)- and (24S)-cycloart-25-en-3b,24-diols, palmitic acid and 1-octacosanol were isolated from the leaves of Artemisia roxburghiana Bess (Asteraceae) of Vietnam Their structures were determined on the basis of spectroscopic methods Keywords: Artemisia roxburghiana; Asteraceae; sesquiterpene lactone; guaianolide Introduction In the chemistry of Artemisia plants of Asteraceae family, sesquiterpene lactones including guaianolides, eudesmanolides and germacranolides are the molecules of interest (Kelsey & Shafizadeh 1979; Tan et al 1998) The guaiane-type sesquiterpene lactones are recognised as a diverse group of natural compounds with varied stereochemical and functional groups (Budeˇsˇ´ınsky´ & Sˇaman 1995) Artemisia roxburghiana Bess (Vietnamese name: Ngải ru`’ng) is a subshrub of 50– 100 cm tall and is used to treat fever and intestinal worms (Hayat et al 2009) As a part of our study of sesquiterpene lactones from species of the family Asteraceae A roxburghiana was investigated The study showed the accumulation of guaianolides with the exclusive H-5a, H-6b, H-7a and H-11a stereochemistry in this plant (Phan et al 2012) In the search for minor guaianolides, a new guaianolide, 11-epi-8a-hydroxyarborescin (1), together with a mixture of two known epimeric cycloartane triterpenoids, (24R)- and (24S)-cycloart25-en-3b,24-diols (3), palmitic acid (4) and 1-octacosanol (5) were isolated from the leaves of A roxburghiana Results and discussion The dried leaves of A roxburghiana were extracted with MeOH, and the resulting MeOH extract was sequentially fractionated using solvents of increasing polarities to give n-hexane-, CH2Cl2and EtOAc-soluble fractions The CH2Cl2-soluble fraction was fractionated by repeated silica gel column chromatography (CC) to give compounds –5 The structures of the known compounds – were determined by comparing their spectroscopic data with the reported literature values (Levy 1976; Pei et al 2007) Compound was isolated as a white amorphous powder (ẵa24 D ỵ 215.5, CHCl3) and its molecular formula was determined as C15H20O4 on the basis of the HR-ESI-TOF-MS spectrum *Corresponding author Email: phanminhgiang@yahoo.com q 2013 Taylor & Francis Downloaded by [Aston University] at 08:09 04 September 2014 Natural Product Research 1857 of The 1H, 13C NMR and HSQC spectroscopic data of revealed the presence of three methyl groups, two sp3 methylenes, five sp3 methines including two oxymethines [dH 4.29 (1H, t, J ¼ 10.5 Hz) and dC 79.0 (d), and dH 3.86 (1H, ddd, J ¼ 10.5, 10.5, 3.5 Hz) and dC 64.6 (d); IR: nmax 3454 cm21], two oxygenated tertiary carbons of an epoxide ring [dC 72.3 (s) and 60.6 (s)], two olefinic carbons of a trisubstitued double bond [dH 5.56 (1H, br s); dC 140.6 (s) and 124.8 (d)] and a lactone carbonyl group [dC 179.6 (s); IR: nmax 1759 cm21] Thus, the spectroscopic data of agreed well with a sesquiterpene lactone of the guaiane type (Budeˇsˇ´ınsky´ & Sˇaman 1995) and HMBC correlations (Figure 1) supported the same planar structure of as that of 8ahydroxyarborescin (Wong & Brown 2002) However, was determined to be an epimer of 8ahydroxyarborescin at C-11, since the 13C NMR chemical shifts at C-11 (dC 38.3) and C-13 (dC 9.7) clearly indicated the H-11a orientation (Budeˇsˇ´ınsky´ and Sˇaman 1995) The chemical shifts of C-11 and C-13 reported for 8a-hydroxyarborescin are dC 40.9 and 16.1, respectively (Wong & Brown 2002) NOESY spectrum also supported the stereochemical assignments of the stereocenters of as H-5a, H-6b, H-7a and H-8b on the basis of the correlations between H3-13 (dH 1.28) and H-6b (dH 4.29), between H-5a (dH 2.86) and H-7a (dH 1.99) and between H-8b (dH 3.86) and H3-13; no correlations were observed between H3-13 and H-5a/H-7a (Figure 1) Therefore, the structure of was determined to be 11-epi-8a-hydroxyarborescin A diastereomeric compound of 1, deacetylglobicin, was isolated from A absinthium (Lee et al 1971; Kasamov et al 1984) Experimental 3.1 General experimental procedures Optical rotations were measured on a JASCO P-1030 digital polarimeter FT-IR spectra were recorded on a Horiba FT-710 spectrophotometer HR-ESI-TOF-MS spectra were measured on an Applied Biosystem QSTAR XL mass spectrometer 1H (500 MHz), 13C NMR and DEPT (125 MHz) spectra were recorded on a Bruker Avance 500 NMR spectrometer Silica gels (0.063 – 0.200 mm, 0.040 – 0.063 mm and 0.015 – 0.040 mm) (Merck, Darmstadt, Germany) were used for open-CC and flash chromatography Thin-layer chromatography (TLC) was carried out on TLC silica gel 60 F254 (Merck, Darmstadt, Germany) and detected by spraying with 1% vanillin in concentrated H2SO4, followed by heating on a hot plate at 2008C 3.2 Plant material The leaves of A roxburghiana Bess (Asteraceae) were collected in Ha Giang province, Vietnam in November 2008 The plant was identified by Mr Nguyen Quoc Binh, a botanist of the Institute of Biological Resources and Ecology, Vietnam Academy of Science and Technology, Hanoi, 14 O H O H O 10 OH H H OH OH H 15 H 11 O 12 O 13 H O O Figure Structure, NOESY and HMBC correlations of compound HMBC NOESY O O 1858 P.M Giang et al Downloaded by [Aston University] at 08:09 04 September 2014 Vietnam Voucher specimen of the plant (voucher number: VMN-B0000302) was deposited at the same Institute 3.3 Extraction and isolation The powdered dried leaves of A roxburghiana (6 kg) were extracted with MeOH at room temperature (three times, each time for three days) The MeOH extract was successively partitioned between water and n-hexane, CH2Cl2 and EtOAc to give the corresponding soluble fractions Part of the CH2Cl2-soluble fraction (42 g) was subjected to silica gel CC using nhexane/acetone 49:1, 29:1, 19:1, 6:1, 3:1 and 1:1 to give eleven fractions Silica gel CC of fraction (3.3 g) eluting with n-hexane/acetone 9:1, 6:1, 3:1 and 1:1 gave compound (15 mg) Repeated silica gel CC of fraction (3.8 g) eluting with n-hexane/EtOAc 19:1, 9:1, 6:1, 3:1 and 1:1 gave a mixture of compounds and (5 mg), and compound (3 mg) Compound (3 mg) were obtained from fractions (0.33 g) on washing with a mixture of n-hexane/acetone 11-epi-8a-Hydroxyarborescin (1): white amorphous powder; ẵa24 D ỵ 215.5 (c 0.11, CHCl3); IR (film) nmax cm21: 3454, 1759, 1441, 1381, 1261, 1222, 1181; 1H NMR (CDCl3): d 1.28 (3H, d, J ¼ 7.5 Hz, 13-CH3), 1.35 (3H, s, 14-CH3), 1.93 (3H, br s, 15-CH3), 1.99 (1H, ddd, J ¼ 10.5, 10.5, 7.0 Hz, H-7), 2.12 (1H, d, J ¼ 18.0 Hz, H-2a), 2.16 (1H, dd, J ¼ 14.5, 10.5 Hz, H-9b), 2.33 (1H, dd, J ¼ 14.5, 3.5 Hz, H-9a), 2.76 (2H, m, H-2b, H-11), 2.86 (1H, d, J ¼ 10.5 Hz, H5), 3.86 (1H, ddd, J ¼ 10.5, 10.5, 3.5 Hz, H-8), 4.29 (1H, t, J ¼ 10.5 Hz, H-6), 5.56 (1H, br s, H3) 13C NMR (CDCl3): d 9.7 (C-13), 18.2 (C-15), 22.7 (C-14), 38.3 (C-11), 39.2 (C-2), 43.5 (C9), 51.6 (C-5), 56.2 (C-7), 60.6 (C-10), 64.6 (C-8), 72.3 (C-1), 79.0 (C-6), 124.8 (C-3), 140.6 (C4), 179.6 (C-12); Positive-ion HR-ESI-TOF-MS: m/z 287.1255, [M þ Na]þ (calcd for C15H20O4Na: 287.1253) Acknowledgements This work was supported by the National Foundation for Science and Technology Development (NAFOSTED, Hanoi, Vietnam) References Budeˇsˇ´ınsky´ M, Sˇaman D (1995) Carbon-13 NMR spectra of sesquiterpene lactones Ann Rep NMR Spectrosc 30:231–475 Hayat MQ, Khan MA, Ashraf M, Jabeen S (2009) Ethnobotany of the genus Artemisia L (Asteraceae) in Pakistan Ethnobot Res Appl 7:147–162 Kasamov Shz, Abdullaev MD, Yusunov MI, Sidyakin GP, Yagudaev MR (1984) New guaianolides from Artemisia absinthium Chem Nat Compd 20:754–755 Kelsey RG, Shafizadeh F (1979) Sesquiterpene lactones and systematics of the genus Artemisia Phytochemistry 18:1591–1611 Lee KH, Matsueda S, Geissman TA (1971) Sesquiterpene lactones of Artemisia: new guaianolides from fall growth of A douglasiana Phytochemistry 10:405–410 Levy GC (1976) Topics in carbon-13 NMR spectroscopy Vol New York, NY: John Wiley & Sons Pei YG, Wu QX, Shi YP (2007) Triterpenoids and other constituents from Euphorbia humifusa J Chin Chem Soc 54:1565–1572 Phan MG, Tran TTN, Phan TS, Otsuka H, Matsunami K (2012) Two new sesquiterpene lactones and other chemical constituents of Artemisia roxburghiana Biochem Syst Ecol 45:115–119 Tan RX, Zheng WF, Tang HQ (1998) Biologically active substances from the genus Artemisia Planta Med 64:295–302 Wong HF, Brown GD (2002) Dimeric guaianolides and a fulvenoguaianolide from Artemisia myriantha J Nat Prod 65:481–486  ... http://dx.doi.org/10.1080/14786419.2013.768991 A new guaianolide from Artemisia roxburghiana Phan Minh Gianga*, Tran Thi Thanh Nhana, Phan Tong Sona, Katsuyoshi Matsunamib and Hideaki Otsukab a Faculty of Chemistry, VNU... cm tall and is used to treat fever and intestinal worms (Hayat et al 2009) As a part of our study of sesquiterpene lactones from species of the family Asteraceae A roxburghiana was investigated... the accumulation of guaianolides with the exclusive H- 5a, H-6b, H- 7a and H-1 1a stereochemistry in this plant (Phan et al 2012) In the search for minor guaianolides, a new guaianolide, 11-epi- 8a- hydroxyarborescin