Advanced
A New Apotirucallane-type Triterpenoid from the Fruit of Melia azedarach
A New Apotirucallane-type Triterpenoid from the Fruit of Melia azedarach
Natural Product Sciences. 2013. Dec, 19(4): 342-346
Copyright © 2013, The Korean Society of Pharmacognosy
  • Received : September 30, 2013
  • Accepted : November 22, 2013
  • Published : December 31, 2013
Download
PDF
e-PUB
PubReader
PPT
Export by style
Article
Author
Metrics
Cited by
TagCloud
About the Authors
Qinghao Jin
College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
Chul Lee
College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
Jin Woo Lee
College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
Moon-Soon Lee
College of Agriculture, Life and Environmental Sciences, Chungbuk National University, Cheongju 361-763, Korea
Mi Kyeong Lee
College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
Bang Yeon Hwang
College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
byhwang@chungbuk.ac.kr

Abstract
A new apotirucallane-type triterpenoid, 3α-tigloylsapelin D ( 1 ) together with five known triterpenoids such as meliasenin B ( 2 ), sendanolactone ( 3 ), (−)-12β-hydroxykulactone ( 4 ), cinamodiol ( 5 ), and 3α-hydroxytirucalla-7,24(25)-dien-6-oxo-21,16-olide ( 6 ) were isolated from the fruits of Melia azedarach . Their structures were established on the basis of various NMR spectroscopic analyses including 2D-NMR techniques (HSQC, HMBC, and NOESY) and HR-FAB-MS data.
Keywords
Introduction
Melia azedarach L. (Meliaceae) is a deciduous tree which is native to Persia, India, and China, and distributed widely in China, Japan, and Southeast Asia. The dried stem bark, root bark, and fruit of this plant have been used as anthelmintic, antifeedant, and for the treatment of leprosy, eczema, asthma, malaria, fever, cholelithiasis, acariasis, and pain (Tang and Eisenbrand, 2011 ; Jung and Shin, 1990) . Previous phytochemical studies on this plant have afforded a wide range of compounds including limonoid, triterpenoid, steroid, alkaloid, and flavonoid glycosides (Zhao ., 2010) . M. azedarach and limonoids have attracted considerable interest because of their biological activivities, including antioxidant, anticancer, antimicrobial, antifeedant, insecticidal, antifungal, anti-inflammatory, and analgesic effects (Tan and Luo, 2011 ; Marimuthu ., 2013 ; Kim ., 1994 ; Akihisa ., 2013 ; Liu ., 2011 ; Carpinella ., 2003a , 2003b ; Xie ., 2008) .
We investigated the chemical constituents of the fruits of this plant and found a new apotirucallane-type triterpenoid along with five known compounds. The structure of the new compound was elucidated by means of spectroscopic methods including 2D NMR techniques and mass spectrometry to be named as 3α-tigloylsapelin D ( 1 ).
Experimental
General Experimental Procedures − Optical rotations were determined on JASCO DIP-370 polarimeter at 25 ℃. NMR spectra were obtained using a Bruker AMX-500 MHz NMR spectrometer. HR-FAB-MS and ESI-MS spectra were obtained on JMS 700 (JEOL, Tokyo, Japan) and VG Autospec Ultima (Micromass, Manchester, UK) mass spectrometers, respectively. Open column chromatography was performed using a silica gel 60 (Kiesel gel 60, 700 - 230 and 230 - 400 mesh, Merck). Preparative HPLC was carried out on a Waters system (two 515 pumps and a 2996 photodiode array detector) and a YMC J’sphere ODS-H80 column (4 μm, 150 × 20 mm), using the mixed solvent system CH 3 CN/H 2 O at a flow rate of 6.0 mL/min. Thin layer chromatography (TLC) was performed on precoated silica gel 60 F 254 (0.25 mm, Merck). All other chemicals and reagents were analytical grade.
Plant Material − The dried fruits of M. azedarach were purchased from Kyung-dong market, Seoul, Korea, in October 2010. The voucher specimen (CBNU 2010-003) was identified by Emeritus Professor Kyong Soon Lee and deposited at the Herbarium of College of Pharmacy, Chungbuk National University.
Extraction and Isolation − The dried fruits (1.0 kg) were extracted three times with methanol (3 × 2 L) at room temperature. The solvent was removed at reduced pressure to give a brown residue (179 g). The extract was suspended in H 2 O (1 L), and separated with n -hexane (3 × 1 L), CH 2 Cl 2 (3 × 1 L), and EtOAc (3 × 1 L), respectively. The CH 2 Cl 2 extract (12 g) was then subjected to column chromatography over silica gel (column: 20 cm × 7.0 cm) with CH 2 Cl 2 - MeOH gradient (100 : 0 - 0 : 100) to yield 7 fractions (MA1 - MA7). Following silica gel column chromatography of MA4 fraction with a solvent gradient of EtOAc in n -hexane yielded 6 subfractions (MA4-1 - MA4-6). Among them, MA4-1 fraction yielded compound 1 (2.6 mg) by an additional purification step on the RPHPLC (MeCN : H 2 O gradient from 85 : 15 to 100 : 0). And then, compound 2 (3.0 mg) was isolated by RPHPLC (MeCN : H 2 O = 75 : 25, isocratic) from AM4-4 fraction. Following silica gel column chromatography of MA3 fraction with a solvent gradient of ethyl acetate in nhexane yielded 6 subfractions (MA3-1-MA3-6). Compounds 3 (4.5 mg) and 4 (2.5 mg) were isolated from MA3-2-1 fraction by RP-HPLC (MeCN : H 2 O = 80 : 20, isocratic). The MA3-3-5 fraction was further separated on RPHPLC (MeCN : H 2 O gradient from 60 : 40 to 80 : 20) to give compounds 5 (4.0 mg) and 6 (2.0 mg).
3α-Tigloylsapelin D (1) − Amorphous powder; α D 25 : −49 ( c 0.05, CHCl 3 ); 1 H-NMR (500 MHz, CDCl 3 ) and 13 C-NMR (125 MHz, CDCl 3 ); see Table 1 ; HR-FBA-MS m/z 595.3977 [M+ Na] + (calcd for C 35 H 56 O 6 Na, 595.3975).
1H- (500 MHz) and13C-NMR (125MHz) data of compound1(in CDCl3)a
PPT Slide
Lager Image
a) Assignments were confirmed by HMQC, HMBC and NOESY spectra.
Meliasenin B (2) − White solid; α D 25 : −28 ( c 0.1, MeOH); 1 H-NMR (500 MHz, CD 3 OD): δ 5.69 (1H, br d, J = 2.5 Hz, H-7), 5.17 (1H, t, J = 7.0 Hz, H-24), 4.31 (1H, td, J = 10.5, 7.5 Hz, H-16), 3.21 (1H, t, J = 8.0 Hz, H-3), 3.10 (1H, td, J = 10.0, 3.5 Hz, H-9), 1.72 (3H, s, H-27), 1.66 (3H, s, H-26), 1.33 (3H, s, H-29), 1.29 (3H, s, H-30), 1.09 (3H, s, H-18), 1.05 (3H, s, H-29), 0.90 (3H, s, 19); 13 C-NMR (125 MHz, CD 3 OD): δ 200.8 (6), 181.0 (C-21), 169.4 (C-8), 132.1 (C-25), 123.7 (C-7), 123.3 (C-24), 81.7 (C-16), 78.0 (C-3), 65.5 (C-5), 57.4 (C-17), 55.9 (C-14), 49.7 (C-9), 44.9 (C-20), 44.3 (C-10), 39.2 (C-13), 37.8 (C-4), 36.3 (C-1), 34.4 (C-15), 28.8 (C-22), 28.8 (C-12), 28.8 (C-30), 27.5 (C-28), 26.0 (C-2), 25.6 (C-23), 24.4 (C-26), 20.1 (C-18), 16.5 (C-27), 16.1 (C-11), 14.1 (C-29), 12.9 (C-19). ESI-MS m/z 491.43 [M + Na] + .
Sendanolactone (3) − White solid; α D 25 : −35 ( c 0.1, MeOH); 1 H-NMR (500 MHz, CD 3 OD): δ 5.78 (1H, br d, J = 2.5 Hz, H-7), 5.17 (1H, t, J = 7.5 Hz, H-24), 4.30 (1H, td, J = 11.5, 8.0 Hz, H-16 Hz), 1.72 (3H, s, H-27), 1.66 (3H, s, H-26), 1.37, 1.36, 1.34, 1.15, 1.05 (15H, s, H-18, 19, 28, 29, 30 each); 13 C-NMR (125 MHz, CD 3 OD): δ 215.5 (C-3), 199.1 (C-6), 180.8 (C-21), 169.8 (C-8), 132.1 (C-25), 123.5 (C-7), 123.3 (C-24), 81.6 (C-16), 64.9 (C-5), 57.3 (C-17), 55.9 (C-14), 48.6 (C-9), 48.2 (C-4), 46.7 (C-20), 44.8 (C-10), 39.1 (C-13), 36.4 (C-1), 34.3 (C-15), 33.5 (C-2), 28.8 (C-30), 28.7 (C-22), 28.6 (C-12), 25.6 (C-23), 24.4 (C-27), 24.3 (C-28), 20.7 (C-29), 19.9 (C-18), 16.5 (C-26), 16.1 (C-11), 12.4 (C-19). ESI-MS m/z 489.50 [M+ Na] + .
(−)-12β-Hydroxykulactone (4) − Colorless oil; α D 25 : −24 ( c 0.1, MeOH); 1 H-NMR (500 MHz, CD 3 OD): δ 5.41 (1H, br s, H-7), 5.14 (1H, t, J = 7.0 Hz, H-24), 4.26 (1H, dd, J = 18.0, 10.0 Hz, H-16α), 3.98 (1H, dd, J = 9.5, 5.0 Hz, H-12α), 2.85 (1H, td, J = 14.5, 5.0 Hz, H-9), 1.69 (3H, s, H-27), 1.65 (3H, s, H-26), 1.41 (3H, s, H-30), 1.15 (3H, s, 28), 1.08 (3H, s, H-29), 1.04 (3H, s, H-19), 0.87 (3H, s, H-18); 13 C-NMR (125 MHz, CD 3 OD): δ 217.7 (C-3), 182.0 (C-21), 143.6 (C-8), 131.8 (C-25), 123.9 (C-24), 118.5 (C-7), 82.5 (C-16), 70.8 (C-12), 54.7 (C-13), 53.1 (C-17), 52.4 (C-5), 48.4 (C-4), 48.3 (C-9), 45.3 (C-20), 44.0 (C-14), 38.1 (C-1), 36.0 (C-15), 35.1 (C-10), 34.4 (C-2), 33.3 (C-30), 30.1 (C-11), 28.4 (C-22), 25.4 (C-23), 24.7 (C-26), 24.1 (C-6), 23.7 (C-29), 20.7 (C-28), 19.3 (C-18), 16.9 (C-27), 11.7 (C-19). ESI-MS m/z 491.25 [M + Na] + .
Cinamodiol (5) −White solid; α D 25 : −34 ( c 0.125, MeOH); 1 H-NMR (500 MHz, CD 3 OD): δ 5.37(1H, m, H-7), 5.16 (1H, br td, J = 6.8 Hz, H-24), 4.28 (1H, dd, J = 17.5, 9.5 Hz, H-16α), 3.96 (1H, dd, J = 9.5, 5.0 Hz, H-12α), 3.20 (1H, dd, J = 10.0, 6.0 Hz, H-3α), 1.71 (3H, s, H-27), 1.66 (3H, s, H-26), 1.37 (3H, s, H-30), 0.97 (3H, s, H-29), 0.88 (3H, s, H-19), 0.87 (3H, s, H-28), 0.82 (3H, s, H-18), 13 C-NMR (125 MHz, CD 3 OD): δ 181.9 (C-21), 143.4 (C-8), 131.6 (C-25), 124.0 (C-24), 118.6 (C-7), 82.4 (C-16), 78.3 (C-3), 70.9 (C-12), 54.6 (C-14), 53.0 (C-17), 50.8 (C-5), 48.5 (C-9), 45.2 (C-20), 44.0 (C-13), 38.6 (C-4), 36.9 (C-1), 35.8 (C-15), 34.9 (C-10), 33.0 (C-30), 30.1 (C-22), 28.4 (C-11), 26.9 (C-2), 26.7 (C-28), 25.3 (C-27), 24.5 (C-23), 24.9 (C-6), 19.0 (C-19), 16.6 (C-26), 13.8 (C-29), 12.0 (C-18). ESI-MS m/z 493.33 [M+ Na] + .
3α-Hydroxytirucalla-7,24(25)-dien-6-oxo-21,16-olide (6) − White solid; α D 25 : −42 ( c 0.1, MeOH); 1 H-NMR (500 MHz, CD 3 OD): δ 5.69 (1H, br d, J = 2.5 Hz, H-7), 5.17 (1H, br dt, J = 6.0 Hz, H-24), 4.31 (1H, dt, J = 10.5, 7.5 Hz, H-16α), 3.29 (1H, br s, H-3α), 3.20 (1H, dt, J = 8.0, 2.0 Hz, H-9), 1.72 (3H, s, H-27), 1.67 (3H, s, H-26), 1.34 (3H, s, H-28), 1.23 (3H, s, H-28), 1.14 (3H, s, H- 29), 1.07 (3H, s, H-18), 0.92 (3H, s, H-19); 13 C-NMR (125 MHz, CD 3 OD): δ 202.2 (C-6), 181.1 (C-21), 169.5 (C-8), 132.1 (C-25), 123.7 (C-7), 123.3 (C-24), 81.7 (C-16), 76.0 (C-3), 60.5 (C-5), 57.4 (C-17), 55.9 (C-14), 49.7 (C-9), 44.8 (C-20), 44.1 (C-10), 39.1 (C-13), 36.4 (C-4), 34.4 (C-15), 30.6 (C-1), 28.8 (C-22), 28.8 (C-12), 28.8 (C-30), 27.3 (C-28), 25.6 (C-23), 24.4 (C-27), 24.2 (C-2), 20.7 (C-29), 20.1 (C-18), 16.5 (C-26), 16.0 (C-11), 13.1 (C-19). ESI-MS m/z 491.33 [M + Na] + .
Results and Discussion
The CH 2 Cl 2 -soluble fraction of the dried fruits of M. azedarach was subjected to silica gel column chromatography and preparative RP-HPLC which led to the isolation of six compounds including a new apotirucallane-type triterpenoid, 3α-tigloylsapelin D ( 1 ) ( Fig. 1 ). Among these compounds, five known compounds were identified as meliasenin B ( 2 ) (Zhang ., 2010) , sendanolactone ( 3 ) (Faizi ., 2002 ; Ochi ., 1977) , (-)-12β-hydroxykulactone ( 4 ) (Cantrell ., 1999) , cinamodiol ( 5 ) (Kelecom ., 1996) , and 3α-hydroxytirucalla-7,24(25)-dien-6-oxo-21,16-olide ( 6 ) (Tan ., 2010) by comparing the 1 H-HMR, 13 C-NMR and MS spectroscopic data with those in the literature.
PPT Slide
Lager Image
The structures of compounds 1 - 6 isolated from M. azedarach.
Compound 1 was isolated as white amorphous powder. The HR-FAB-MS showed the quasi-molecular ion peak at m/z 595.3977 [M + Na] + (calcd for C 35 H 56 O 6 Na, 595.3975), consistent with the molecular formula of C 35 H 56 O 6 . The 1 H-NMR spectrum ( Table 1 ) showed seven tertiary methyl groups (δ H 0.89, 0.93, 0.94, 1.02, 1.11, each 3H, s), one olefinic proton (δ H 5.52), and five oxygenated protons (δ H 3.46, 3.90, 3.93, 4.01, 4.71). The 13 C-NMR spectra ( Table 1 ) showed the presences of seven methyls, eight methylenes (one oxygenated), nine methines (three oxygenated, one olefinic), and six quaternary carbons (one olefinic and one oxygenated). The remaining 1 H-NMR and 13 C-NMR data ( Table 1 ) indicated the presence of a tigloyl group [δ H 6.88 (1H, dd, 7.0, 1.5 Hz, H-3'), 1.87 (3H, t, 1.0 Hz, H-4'), and 1.81 (3H, dd, 7.0, 1.0 Hz, H-5'); δ C 167.6, 136.7, 129.2, 14.4, 12.1]. The aforementioned data suggested that compound 1 was a triterpenoid having an apotirucallane skeleton with a tigloyl ester group in the molecule. Moreover, these data closely resembled to those of sapelin D and 3α-senecioyl-21,24 R -epoxyapotirucall-14-ene-7α,23R,25-triol, apotirucallane-type triterpenoid from Entandrophragma cylindricurn and Cedrela sinensis , respectively (Lyons and Taylor, 1976 ; Mitsui ., 2005 , 2007) . The location of tigloyl group was elucidated as C-3 by the observed HMBC correlation between H-3 (δ H 4.71) and C-1' (δ C 167.6) ( Fig. 2 ). In the HMBC spectrum of compound 1 , the correlations between the methylene protons [δ H 3.46 (1H, dd, 11.0, 2.5 Hz, H-21α) and δ H 4.01 (1H, d, 11.0 Hz, H-21β)] and the methine carbon [δ C 86.5 (C-24)] suggested that C-21 was linked to C-24 via an oxygen bridge to form a cyclic ether ( Fig. 2 ). The relative configuration of the tetracyclic core in compound 1 was established on the basis of NOESY experiments ( Fig. 3 ). The NOESY correlations of H-3β/CH 3 -29, CH 3 -19/CH 3 -29, CH 3 -19/CH 3 -30, and CH 3 -30/H-7 indicated the tigloyl ester side chain at C-3 and hydroxyl group at C-7 were both in α-orientation. The large coupling constant ( J = 9.0 Hz) between H-23 and H-24 indicated that the tetrahydropyran ring of the side chain at C-17 was in a chair conformation (Mitsui ., 2005 ; Zhang ., 2012) . Further NOE correlations between H-17/H-21β, H-17/H-23, CH 3 -18/H-20, H-20/H-21α, H-21α/H-22α, H-21α/H-24, and H-22α/H-24 revealed that the configuration at C-23 and that at C-24 were both R . Therefore, the structure of 1 was determined as 3α-tigloyl-21,24Repoxyapotirucall-14-ene-7α,23R,25-triol, and named 3α-tigloylsapelin D ( 1 ).
PPT Slide
Lager Image
Key HMBC (→) correlations of compound 1.
PPT Slide
Lager Image
Key NOESY (↔) correlations of compound 1.
The genus Melia is well-known as a rich and valuable source of highly functionalized nortriterpenoid such as limonoid derivatives (Tan and Luo, 2011) . Apotirucallanetype triterpenoids, which have undergone the apo-euphol rearrangement to form a C = C bond at C-14 with the methyl group shifted to C-8, were isolated from the genus Melia (Zhao ., 2010 ; Mitsui ., 2005 ; Nakanishi ., 1986 ; Zeng ., 1995a ; Rogers ., 1998 ; Fukuyama ., 2000) .
However, apotirucallane-type triterpenoids having a substituted tetrahydropyran ring side chain have been rarely found (Zeng ., 1995b , 1995c) . Therefore, the isolation of 3α-tigloylsapelin D ( 1 ) in this study provides further example of the rare apotirucallae-type triterpenoid with tetrahydropyran ring system in the molecule.
Acknowledgements
This work was supported by the research grant of the Chungbuk National University in 2011.
References
Akihisa T. , Pan X. , Nakamura Y. , Kikuchi T. , Takahashi N. , Matsumoto M. , Ogihara E. , Fukatsu M. , Koike K. , Tokuda H. (2013) Limonoids from the fruits of Melia azedarach and their cytotoxic activities. Phytochemistry 89 59 - 70    DOI : 10.1016/j.phytochem.2013.01.015
Cantrell C.L. , Rajab M.S. , Franzblau S.G. , Fischer N.H. (1999) Antimycobacterial triterpenes from Melia volkensii. J. Nat. Prod. 62 546 - 548    DOI : 10.1021/np980288u
Carpinella M.C. , Defago M.T. , Valladares G. , Palacios S.M. (2003a) Antifeedant and insecticide properties of a limonoid from Melia azedarach (Meliaceae) with potential use for pest management. J. Agric. Food Chem. 51 369 - 374    DOI : 10.1021/jf025811w
Carpinella M.C. , Giorda L.M. , Ferrayoli C.G. , Palacios S.M. (2003b) Antifungal effects of different organic extracts from Melia azedarach L. on phytopathogenic fungi and their isolated active components. J. Agric. Food Chem. 51 2506 - 2511    DOI : 10.1021/jf026083f
Faizi S. , Wasi A. , Siddiqui B.S. , Naz A. (2002) New terpenoids from the roots of Melia azedarach. Aust. J. Chem. 55 291 - 296    DOI : 10.1071/CH01101
Fukuyama Y. , Ogawa M. , Takahashi H. , Minami H. (2000) Two new meliacarpinins from the roots of Melia azedarach. Chem. Pharm. Bull. 48 301 - 303    DOI : 10.1248/cpb.48.301
Jung B.S. , Shin M.K. (1990) Encyclopedia of Illustrated Korean Natural Drugs Young Lim Sa Seoul 773 -
Kelecom A. , Cabral M.M.O. , Garcia E.S. (1996) A new euphane triterpene from the Brazilian Melia azedarach. J. Braz. Chem. Soc. 7 39 - 41    DOI : 10.5935/0103-5053.19960006
Kim H.M. , Oh G.T. , Han S.B. , Hong D.H. , Hwang B.Y. , Kim Y.H. , Lee J.J. (1994) Comparative studies of adriamycin and 28-deacetyl sendanin on in vitro growth inhibition of human cancer cell lines. Arch. Pharm. Res. 17 100 - 103    DOI : 10.1007/BF02974231
Liu H.B. , Zhang C.R. , Dong S.H. , Dong L. , Wu Y. , Yue J.M. (2011) Limonoids and triterpenoids from the seeds of Melia azedarach. Chem. Pharm. Bull. 59 1003 - 1007    DOI : 10.1248/cpb.59.1003
Lyons C.W. , Taylor D.R. (1976) Stereochemistry of sapelin B; correlation with sapelin D. Anomalies in the use of shift reagents for determining the absolute configurations of a-glycols. J. Chem. Soc. Chem. Commun. 16 647 - 648    DOI : 10.1039/c39760000647
Marimuthu S. , Balakrishnan P. , Nair S. (2013) Phytochemical investigation and radical scavenging activities of Melia azedarach and its DNA protective effect in cultured lymphocytes. Pharm. Biol. 51 1331 - 1340    DOI : 10.3109/13880209.2013.791323
Mitsui K. , Maejima M. , Saito H. , Fukaya H. , Hitotsuyanagi Y. , Takeya K. (2005) Triterpenoids from Cedrela sinensis. Tetrahedron 61 10569 - 10582    DOI : 10.1016/j.tet.2005.08.044
Mitsui K. , Saito H. , Yamamura R. , Fukaya H. , Hitotsuyanagi Y. , Takeya K. (2007) Apotirucallane and tirucallane triterpenoids from Cedrela sinensis. Chem. Pharm. Bull. 55 1442 - 1447    DOI : 10.1248/cpb.55.1442
Nakanishi T. , Inada A. , Nishi M. , Miki T. , Hino R. , Fujiwara T. (1986) The structure of a new natural apotirucallane-type triterpene and the stereochemistry of the related terpenes. Chem. Lett. 15 69 - 72    DOI : 10.1246/cl.1986.69
Ochi M. , Kotsuki H. , Tokoroyama T. , Kubota T. (1977) The structure of sendanolactone, a new triterpenoid from Melia azedarach L. var. japonica Makino. Bull. Chem. Soc. Jpn. 50 2499 - 2500    DOI : 10.1246/bcsj.50.2499
Rogers L.L. , Zeng L. , Kozlowski J.F. , Shimada H. , Alali F.Q. , Johnson H.A. , McLaughlin J.L. (1998) New bioactive triterpenoids from Melia volkensii. J. Nat. Prod. 61 64 - 70    DOI : 10.1021/np9704009
Tan Q.G. , Li X.N. , Chen H. , Feng T. , Cai X.H. , Luo X.D. (2010) Sterols and terpenoids from Melia azedarach. J. Nat. Prod. 73 693 - 697    DOI : 10.1021/np1000472
Tan Q.G. , Luo X.D. (2011) Meliaceous limonoids: chemistry and biological activities. Chem. Rev. 111 7437 - 7522    DOI : 10.1021/cr9004023
Tang W. , Eisenbrand G. (2011) Handbook of Chinese Medicinal Plants Wiley-VCH Weinheim 752 -
Xie F. , Zhang M. , Zhang C.F. , Wang Z.T. , Yu B.Y. , Kou J.P. (2008) Antiinflammatory and analgesic activities of ethanolic extract and two limonoids from Melia toosendan fruit. J. Ethnopharmacol. 117 463 - 466    DOI : 10.1016/j.jep.2008.02.025
Zeng L. , Gu Z.M. , Chang C.J. , Wood K.V. , McLaughlin J.L. (1995a) Meliavolkenin, a new bioactive triterpenoid from Melia volkensii (Meliaceae). Bioorg. Med. Chem. 3 383 - 390    DOI : 10.1016/0968-0896(95)00034-E
Zeng L. , Gu Z.M. , Fang X.P. , Fanwick P.E. , Chang C.J. , Smith D.L. , McLaughlin J.L. (1995b) Two new bioactive triterpenoids from Melia volkensii (Meliaceae). Tetrahedron 51 2477 - 2488    DOI : 10.1016/0040-4020(95)00018-4
Zeng L. , Gu Z.M. , Chang C.J. , Smith D.L. , McLaughlin J.L. (1995c) A pair of new apotirucallane triterpenes, meliavolkensins A and B, from Melia volkensii (Meliaceae). Bioorg. Med. Chem. Lett. 5 181 - 184    DOI : 10.1016/0960-894X(95)00004-D
Zhang F. , Wang J.S. , Gu Y.C. , Kong L.Y. (2012) Cytotoxic and antiinflammatory triterpenoids from Toona ciliata. J. Nat. Prod. 75 538 - 546    DOI : 10.1021/np200579b
Zhang Y. , Tang C.P. , Ke C.Q. , Yao S. , Ye Y. (2010) Limonoids and triterpenoids from the stem bark of Melia toosendan. J. Nat. Prod. 73 664 - 668    DOI : 10.1021/np900835k
Zhao L. , Huo C.H. , Shen L.R. , Yang Y. , Zhang Q. , Shi Q.W. (2010) Chemical constituents of plants from the genus Melia. Chem. Biodivers. 7 839 - 859    DOI : 10.1002/cbdv.200900043