A new derivative of furancarboxaldehyde from Chlorophytum laxum R. Br. (Athericaceae)

Journal of Chemistry, Vol. 45 (Special issue), P. 131 - 135, 2007<br /> <br /> <br /> A new derivative of furancarboxaldehyde from<br /> Chlorophytum laxum R. Br. (Athericaceae)<br /> Received 21 March 2007<br /> nguyen thi hoai , pham thanh ky1, chau van minh2, Phan Van Kiem2<br /> 1<br /> <br /> 1<br /> Hanoi Institute of Pharmacy, Ministry of Health<br /> 2<br /> Institute of Natural Products Chemistry, Vietnamese Academy of Science and Technology<br /> <br /> SUMMARY<br /> From the methanol extract of the leaves of Chlorophytum laxum R. Br. (Athericaceae), a new<br /> (1) and two known (2, 3) derivatives of furancarboxaldehyde, and a derivative of anthraquinone<br /> (4) were isolated by various chromatography methods. Their structures were elucidated as 5-<br /> (ethoxymethyl)-2-furancarboxaldehyde (1), 5-hydroxymethyl-2-furancarboxaldehyde (2) and<br /> cirsiumaldehyde (3) and 1,5-dihydroxy-3-hydroxymethylanthraquinone (4) by analyses of the<br /> NMR (1D-, 2D-NMR), EI-MS and ESI-MS spectra. This is the first report of 2, 3, and 4 from C.<br /> laxum.<br /> <br /> I - INTRODUCTION performed on silica gel (Kieselgel 60, 70-230<br /> mesh and 230 - 400 mesh, Merck) or YMC RP-<br /> In previous paper, we have reported the 8 resins (30 - 50 µm, Fujisilisa Chemical Ltd).<br /> isolation and structural elucidation of one new Thin layer chromatography (TLC) was<br /> and three known flavone glycosides from performed on DC-Alufolien 60 F254 (Merck<br /> Chlorophytum laxum, which is used in folk 1.05715) or RP18 F254s (Merck) plates.<br /> medicine. As a part of our work on<br /> phytochemical and bioactive components from 2. Plant material<br /> this plant [4], we report herein the isolation and The roots of Chlorophytum laxum R. Br.<br /> structural determination of a new (1) and two (Athericaceae) were collected in A Roang, A<br /> known (2, 3) derivatives of Dot, A Luoi, Thua-Thien-Hue, in September,<br /> furancarboxaldehyde together with a derivative 2006 and were identified by Dr Duong Duc<br /> of anthraquinone (4) isolated from C. laxum. Huyen, Institute of Ecology and Biological<br /> Resources, VAST. An authentic sample was<br /> II - Experimental deposited at this Institute.<br /> 3. Extraction and isolation<br /> 1. General experimental procedures<br /> The roots (1.0 kg) of C. laxum were washed,<br /> The Electronspray Ionization (ESI) mass dried and powdered, then extracted repeatedly<br /> spectrum was obtained using a AGILENT 1100 with hot MeOH (three times). The combined<br /> LC-MSD Trap spectrometer. The 1H-NMR (500 solutions were evaporated under reduced<br /> MHz) and 13C-NMR (125 MHz) spectra were pressure to give MeOH extract (15.0 g), which<br /> recorded on a Bruker AM500 FT-NMR was suspended in water and then partitioned<br /> spectrometer using TMS as the internal with n-hexane, chloroform, ethyl acetate, n-<br /> standard. Column chromatography (CC) was butanol to give the n-hexane (1.5 g), chloroform<br /> 131<br /> (5.5 g), ethyl acetate (2.6 g), n-butanol 2.0 (g) crystals. Compound 4 (22 mg) was obtained as<br /> extracts and water layer. The chloroform extract orange crystals from the ethyl acetate extract<br /> (5.5 g) was then repeated chromatographed on (2.6 g) after repeated chromatography on silica<br /> silica gel columns to get 1 (15 mg), 2 (45 mg) as gel columns.<br /> white needles, and 3 (17 mg) as pale yellow<br /> <br /> <br /> 4 4<br /> 3 3<br /> <br /> <br /> <br /> 5 2 5 2<br /> 8 7 6 1 6 1<br /> H3CH 2COH 2C CHO HOH 2C CHO<br /> O O<br /> 1 2<br /> <br /> O OH<br /> 3' 4' 4<br /> 3<br /> 8 10 1<br /> 7 9 11 2<br /> 2' 5' 5 2<br /> 1' 6'<br /> O 6 1 6<br /> 14 12 3<br /> 5 13 4 15<br /> OHC CHO<br /> O O CH2OH<br /> OH O<br /> 3 4<br /> Figure 1: The structures of 1 - 4<br /> <br /> 5-(ethoxymethyl)-2-furancarboxaldehyde III - RESULTS AND DISCUSSION<br /> (1): White needles. EI-MS: m/z: 154<br /> [M]+•(C8H10O3). IR (KBr) max (cm-1): 3447.6 Compound 1 was obtained as white needles<br /> (OH), 2981.4, 2866.6(C-H), 1677.5 (C=O), from the methanolic extract of the roots of C.<br /> 1097.2 (C-O-C).1H-NMR (500 MHz, CDCl3) laxum. The 1H-NMR spectrum of 1 showed a<br /> and 13C-NMR (125 MHz, CDCl3): see tables 1 singlet signal at 9.62 (1H) of the aldehydic<br /> and 2. proton, two doublets at 7.21 (1H, J = 3.5 Hz)<br /> 5-hydroxymethyl-2-furancarboxaldehyde and 6.51 (1H, J = 3.5 Hz) suggesting the<br /> (2): White needles. EI-MS m/z: 126 [M]+• presence of a furano ring [2], a singlet of the<br /> (C6H6O3). 1H-NMR (500 MHz, CDCl3) and 13C- methylene group bearing oxygen atom at 4.53<br /> NMR (125 MHz, CDCl3): see tables 1 and 2. (2H). The ethylene group bearing to oxygen<br /> atom was confirmed at 3.59 (2H, q, J = 7.0<br /> Cirsiumaldehyde (3): Pale yellow crystals.<br /> ESI-MS m/z: 235 [M+H]+ (C12H10O5). Mp 115- Hz) and at 1.24 (3H, t, J = 7.0 Hz). The 13C-<br /> NMR spectrum of 1 exhibited signals of 8<br /> 116oC, IR (KBr) max (cm-1): 3325.7 (OH),<br /> 2931.2, 2852.3 (C-H), 1667.2 (C=O), 1045.5 carbons including an aldehydic carbon at<br /> (C-O-C). 1H-NMR (500 MHz, CDCl3) and 13C- 177.71, the furan ring at 158.80, 152.61,<br /> NMR (125 MHz, CDCl3): see tables 1 and 2. 121.84 and 110.96 [2], a methylene carbon at<br /> 1,5-dihydroxy-3- 64.67 and a ethylene group at 66.63 and<br /> 15.05. The chemical shift assignments of<br /> hydroxymethylanthraquinone (4): Orange<br /> protons and carbons of 1 were elucidated from<br /> crystal, mp. 233-235oC. ESI-MS m/z: 271<br /> its HSQC and HMBC spectra. In the HSQC<br /> [M+H]+ (C15H10O5). 1H-NMR (500 MHz, CDCl3)<br /> and 13C-NMR (125 MHz, CDCl3), see table 3. spectrum, a singlet at H 9.62 coupled with<br /> <br /> 132<br /> signal at C 177.71, proton at 7.21 coupled with carbon at 64.77, as well as signals at<br /> with carbon at 152.61, H-4 at 6.51 linked to 3.59 and 1.24 coupled with carbon signals at<br /> C-4 at 110.96, a singlet at H 4.53 coupled 66.63 and 15.05, respectively.<br /> <br /> Table 1: The 1H-NMR data of 1 - 3<br /> 1 2 3<br /> C a,b a,b a,b<br /> H (J, Hz) HMBC H (J, Hz) HMBC H (J, Hz) HMBC<br /> 1 9.62 (br s) 9,53 (br s) 2 9.63 (br s) 2, 3<br /> 3 7.21 (d, 3.5) 2, 4, 5 7.22 (d, 3,5) 2, 4, 5 7.20 (d, 3.5) 1, 2, 4, 5<br /> 4 6.51 (d, 3.5) 2, 3, 5 6.51 (d, 3,5) 2, 3, 5 6.56 (d, 3.5) 2, 3, 5, 6<br /> 6 4.53 (s) 4, 5, 7 4.65 (d, 3,5) 4, 5 4.63 (s) 4, 5, 6'<br /> 7 3.59 (q, 7.0) 6<br /> 8 1.24 (t, 7.0) 7<br /> 6-OH 3.87 (br s)<br /> 1' 9.63 (br s) 2', 3'<br /> 2' - -<br /> 3' 7.20 (d, 3.5) 1', 2', 4', 5'<br /> 4' 6.56 (d, 3.5) 2', 3', 5', 6'<br /> 5' - -<br /> 6' 4.63 (s) 4', 5', 6<br /> a<br /> Measured in CDCl3, b500 MHz.<br /> <br /> Comparing the NMR data of 1 to those of 5- The NMR spectra of 2 and 3 were very<br /> hydroxymethyl-2-furancarboxaldehyde [2] led similar to those of 1, except for the absence of<br /> to suggest the structure of 1 as 5- the ethylene signals in the NMR spectra of 2<br /> (ethoxymethyl)-2-furancarboxaldehyde (Fig. 1), and 3. This evidence as well as the exhibition of<br /> which was further confirmed by HMBC and MS an ion peak at m/z 126 (corresponding to the<br /> spectra. In the HMBC spectrum, the H-6 proton molecular formula of C6H6O3) in the EI mass<br /> ( 4.53) correlated with C-5 ( 158.80)/C-4 ( spectrum of 2, and a quasi ion peak at m/z 235<br /> 110.96)/C-7 ( 66.63), the H-4 ( 6.51) [M+H]+• (corresponding to the molecular<br /> correlated with C-2 ( 152.61)/C-3 ( formula of C12H10O5) in the ESI mass spectrum<br /> 121.84)/C-6 ( 64.77). This evidence confirmed of 3 led to identify compounds 2 and 3 as 5-<br /> the presence of a furancarboxaldehyde structure hydroxymethyl-2-furancarboxaldehyde and<br /> [2] and the ethylene group linked to C-6 by an cirsiumaldehyde, respectively [2]. These<br /> ether linkage. Furthermore, the EI mass compounds showed antibacterial activity [2].<br /> spectrum of 1 exhibited an ion peak at m/z 154 The NMR data of compound 4 was<br /> [M]+, corresponding to molecular formula compared to those of 1,5-dihydroxy-3-<br /> C8H10O3. From the above data, compound 1 was hydroxymethylanthraquinone and found to<br /> determined to be 5-(ethoxymethyl)-2- match [3]. In addition, all its NMR assignments<br /> furancarboxaldehyde, which was first isolated were reconfirmed by HMQC, HMBC spectra as<br /> from nature. shown in table 3.<br /> <br /> <br /> 133<br />  Table 2: The 13C-NMR data of 1 - 3<br /> 2 3<br /> C 1 a.b a.b<br /> #<br /> C C *C C<br /> <br /> 1 177.71 178.2 177.74 177.7 177.69<br /> 2 152.61 152.2 152.08 152.9 152.79<br /> 3 121.84 124.1 123.23 121.7 121.78<br /> 4 110.96 110.2 109.90 111.8 111.82<br /> 5 158.80 161.6 161.02 157.3 157.21<br /> 6 64.77 57.1 57.26 64.6 64.60<br /> 7 66.63<br /> 8 15.05<br /> 1' 177.7 177.69<br /> 2' 152.9 152.79<br /> 3' 121.7 121.78<br /> 4' 111.8 111.82<br /> 5' 157.3 157.21<br /> 6' 64.6 64.60<br /> a #<br /> Measured in CDCl3, b125 MHz, C of 5-hydroxymethyl-2-furancarboxaldehyde [2], * C of cirsiumaldehyde [2].<br /> <br /> Table 3: The NMR data of 4<br /> a,b a,c<br /> C C<br /> DEPT H<br /> HMBC<br /> 1 161.32 - - -<br /> 2 120.66 CH 7.28 (1H, d, J = 1.0 Hz) C-1, C-4, C-14, C-15<br /> 3 153.65 - - -<br /> 4 117.05 CH 7.68 (1H, d, J = 1.0 Hz) C-2, C-14, C-15, C-6<br /> 5 161.61 - - -<br /> 6 124.37 CH 7.37 (1H, dd, J = 8.0, 1.0 Hz) C-7, C-8, C-10, C-11<br /> 7 137.27 CH 7.80 (1H, dd, J = 8.0, 8.0 Hz) C-8, C-9. C-11, C-12<br /> 8 119.28 CH 7.70 (1H, dd, J = 8.0, 1.0 Hz) C-9. C-12, C-7, C-13<br /> 9 133.31 - - -<br /> 10 181.43 - - -<br /> 11 114.43 - - -<br /> 12 133.09 - - -<br /> 13 191.58 - - -<br /> 14 115.87 - - -<br /> 15 62.03 CH2 4.62 (2H, s) C-2, C-3, C-4<br /> a<br /> Measured in DMSO-d6, b125 MHz, c500 MHz.<br /> <br /> <br /> 134<br />  REFERENCES 3. Sedat Imre, Sezen Sar and Ronald H.<br /> Thomson. Phytochemistry, Vol. 15, 317 -<br /> 1. Vo Van Chi. Vietnamese Medical Plant 320 (1976).<br /> Dictionary, Hanoi Medicine Pub. (1997). 4. Nguyen Thi Hoai, Pham Thanh Ky, Chau<br /> 2. Yue-mao Shen and Quan-zhang Mu. Planta Van Minh, Phan Van Kiem. Pharmaceutical<br /> Medica, Vol. 56, 472 - 474 (1990). Journal, Vol. 372 (4), 29 - 32 (2007).<br /> <br /> <br /> <br /> <br /> 135<br />