- Email: [email protected]
A sesquiterpene and other constituents from Erigeron breviscapus
Pergamon
00314422(!M)EOO11-G
Phymhenuury, Vol. 34 No. 3. pp. 717.719. 1994 Cow&t c 1994 Elswicr Scicna Ltd Pnntcd I” Great Bntarn All rights rc~erwd 0031-9422.94 S7.00+000
A SESQUITERPENE AND OTHER CONSTITUENTS FROM ERIGERON
BRE VISCAPUS
JIANMINYUE, ZHONGWENLIN, DEZU WANG and HANDONGSUN+ Laboratory of Phytochemistry, Kunming Institute of Botany, Academia Sinica, Kunming, 650204, Yunnan, China (Receiued in revised
Key Word Index--Erigeron
form
14 December 1993)
breviscapns; Compositae; erigesides A, B and C.
Abstract-Three new constituent erigesides, A-C, as well as two known compounds, betulabuside A and erigeroside, have been isolated from Erigeron breoiscapus. The structures of the new compounds were established on the basis of spectral analysis.
INTRODUCTION
Erigeron breviscapus (Van) Hand.-Mau is a perennial herb, which grows abundantly in the Yunnan and Guangxi provinces of China. Erigeroside has been found previously in this plant [I]. We report here the isolation and structural elucidation of three new constituents, erigesides A (lb B (2) and C (3) along with two known compounds, betulabuside A (4) and erigeroside (S), from the butanol-soluble fraction of E. breviscapus. RESULTS AND DlSCUS!%ON
Erigeside A (I) was assigned the molecular formula Cz1HJ608 (HRMS). The ion of highest mass, [Ml’ observed at m/z 416 in the EIMS of 1 was shifted to m/z 417 [M + 11’ in the FABMS. Its IR spectrum showed the presence of hydroxyl groups (3150-3600 cm- *) and a carbon-carbon double bond (1634 cm- ‘). The t3C NMR pattern of 1 indicated the presence of a glucose moiety and a 15 carbon atom aglycone moiety. The 13C NMR spectrum of this aglycone moiety revealed four methyl groups, three secondary carbon atoms, five tertiary carbon atoms and three quatemary carbons. The ‘H NMR spectrum of 1 contained signals for an angular methyl group (61.04, 3H, s, H-14), a secondary methyl group (60.95, 3H, d, J=7.0 Hz, H-15). and an isopropyl chain (three signals, see Experimental) attached to the carbon-carbon double bond [2]. The ‘H and ’ 3C NMR spectral assignments (Experimental), based on ‘H-‘H COSY, NOSY, ‘H-13C correlation spectra and DEPT techniques, suggested that the aglycone moiety had a eudesmane skeleton. H-6 is responsible for the singlet signal at 6 5.47 (1H). The signals at 6 2.29 (1H, dd, .I = 14.9,5.8 Hz) and 1.50 (I H, d, J = 14.9 Hz) were assigned to H-8/? and H-8a, respectively. The signal at 64.15 (1H, d,
*Author to whom correspondence. should be addressed.
J=5.8 Hz) correlating with H-8p in the ‘H-‘HCOSY spectrum is typical of H-98 geminal with a hydroxyl group. The quaternary carbon signal at 675.5 in the “CNMR spectrum derives from the C-5 bearing a hydroxyl group [3]. The signal at 63.97 (1H, ddd, J = 14.8, 14.2,4.7 Hz) was attributed to the H-3a geminal with the glucose moiety, and assignment supported by the tertiary carbon signal at 674.6 (C-3) in the *%INMR spectrum. The most probable stereochemistry of carbons C-4, C-5 and C-IO was suggested by comparison of the ‘H NMR and 13C NMR data with those of the known compounds stylotelline [2] and a-carymobolol[3], and confirmed by the ‘H-‘H NOSY spectrum (Fig. 1). Thus, the coupling constants of protons associated with C-3 and C-9 and the ‘H-‘H NOSY spectrum (Fig. 1) established the relative configurations of these carbons. The ‘H NMR signal at 64.38 (IH, d, J=7.8 Hz) and the 13CNMR signal at 6101.7 are assignable to the l-position of the glucose moiety, suggesting the presence of /I-glucose [4]. The structure of erigeside A was thus assigned to be 1. Erigeside B (2), has a molecular formula C,,H,,O, based on the 13CNMR and MS data. Its IR spectrum indicated the presence of hydroxyl groups (3150-3600 cm-‘) and a carbon-carbon double bond (1630 cm-‘). The 400 MHz ‘H NMR spectrum of 2 showed the presence of a methyl group at 60.97 (3H, t, J = 7.2 Hz), two coupled signals at 65.44 (IH, dt, J = 17.5 Hz, 7.6 Hz) and 5.36 (lH, dt, .I= 17.5, 7.3 Hz) characteristic of -CH,-CH=CH-CH,-, and a signal at 63.95 (ZH, dd, J = 7.6, 1.5 Hz) indicative of protons geminal with an oxygen atom. The 13C NMR and ‘H NMR spectra revealed the presence of a /?-glucose moiety [4]; this was supported by the lose of 162 mass units from the [M]’ (m/z 262) to give a weak peak (m/z 100) and a strong peak (m/z 83). The 13CNMR spectrum also revealed the presence of six carbons in the aglycone moiety, a methyl (6 14.6). three methylenes (621.5, 28.8 and 70.4) and two methines (6126.6 and 134.5) in a double bond. 717
JMHUIN
718
YUF et al.
4
3
5
CH~OH
R= “;a OH
RO
Fig. 1.
On the basis of the above data and the i3CNMR assignments (Experimental), the structure of erigeside B was clearly established to be 2. Erigeside C (3), C, ,H,,O, e (HRMS). Its IR spectrum showed the presence of hydroxyl groups (3 150-3550 cm _ ‘), a carbonyl absorption band (1695cm-‘) and aromatic ring (1600 and 1510cm- I). The “C NMR spectrum of 3 indicated the presence of a glucose moiety and a nine carbon atom aglycone moiety; this was supported by the loss of a 162 mass unit from the CM]’ (m/z 360) to give the base peak (m/z 198). The appearance ofsix signals in the 13C NMR spectrum ofthe aglycone moiety corresponded to nine carbon atoms, indicating that the molecule must have a degree of symmetry in its structure. In the COLOC spectrum, the signal at 6 7.39 (ZH, s) correlated with the signals at 6 166.8 (C-7), 149.O(C-3 and C-5) 143.O(C-4) and 120.7 (C-l). The two methoxy groups were assigned to C-3 and C-5, and a hydroxyl group attached to C-4 was evident from examination of the i3CNMR and the COLOC spectra. The ‘H NMR signal at 65.69 (IH. d. J= 8.0 Hz) and the
i3C NMR signal at 696.2 were assigned to the I-position of the fi-glucose moiety, suggesting that the moiety was attached to C-7. The structure of erigeside C was thus elucidated to be 3. Erigeroside and batulabuside A were identified on the basis of spectral data and physical constants [l. 51. In a previous study [S], the structure of betulabuside A (4) was assigned by spectral analysis of its aglycone and tetraacetate betulabuside A. The ‘“CNMR signals assigned to C-9 of its aglycone and tetraacetate betulabuside A were those at 668.9 and 68.7, respectively. This seems unlikely since the 2-C of an aglycone moiety is generally deshielded (cu A57) on glucoside formation [6, 73. In our study, the C-9 of betuiabuside A was observed at 675.9. WC now report the spectral data and physical constants of betulabuside A.
EXPERIMENTAL
Mp: uncorr.; NMR: ‘H at 400 MHz, ‘-‘C at 100 MHz, CD,OD; FABMS and EIMS: ZAB-HS mass spectrometer. Plant material. Eriyeron hreviscapus (Van.) Hand.Mazz was collected at Kunming, Yunnan province, China. The species was authenticated by Prof. Wu ZhengYi, Kunming Institute of Botany, Academia Sinica, where a voucher specimen is deposited. Extraction and separation. The air-dried powdered whole plant (5 kg) was extracted ( x 3) with 95% EtOH at room temp. The extract was evapd to dryness under red. pres. and the residue (208 g) was dissolved in water (200ml). The aq. soln was partitioned with hexane, EtOAc and n-BuOH to give fractions H (20 g). E (51 g) and N (31 g). respectively.
Sesquiterpene
from Erigeron breuiscapus
Isolation. Fr. N (31 g) was chromatographed on a column of silica gel (300 g) eluting with CHCI, containing gradually increasing amounts of MeOH to give frs l-12. Frs 2 and 3 were combined and passed through a column of RP-8 silica gel with MeOH-Hz0 (3:2) as eluent to yield betulabuside A (41 mg). Frs 4-7 were combined and crystallized from EtOH to afford erigeroside (6.7 g). Frs 8- 10 were combined and chromatographed on an RP-8 silica gel column to afford erigeside A (52 mg) and erigeside B (27 mg). Recrystallization of fr. 11 from MeOH gave erigeside C (57 mg). Erigeside A (1). CZ1H360s (M-2H,O, Found: 380.2196, requires 380.2199), amorphous powder. IR YE: cm- ‘: 3150-3600 (-OH), 1634 (double bond); ‘H NMR 6 (ppm): 1.65 (IH, m, overlapped with H-4/?, Hla), 1.61 (lH, ddd, J= 14.0, 4.8, 2.7 Hz, H-l/?), 1.33 (lH, dddd, J= 14.8, 14.0, 14.0,4.8 Hz, H-2/?), 1.75 (lH, dddd, J = 14.0,4.8,4.7,2.7 Hz, H-2a), 3.97(1H,ddd,J= 14.8, 14.2, 4.7 Hz H-3a), 1.65 (lH, m, H-4/?), 5.47 (lH, s, H-6), 2.99 (lH, dd, J=l4.9, 5.8 Hz, H-8/?), 1.50 (lH, d, J=l4.9 Hz, H-8a), 4.15 (lH, d, J=5.8 Hz, H-9/?), 2.50 (lH, septet, J =6.9Hz,H-11),1.02(3H,d,J=6.9H~H-12),1.15(3H,d, J=6.9 Hz, H-13), 1.04 (3H, s, H-14). 0.95 (3H, d, J =7.0Hz,H-l5),4.38(1H,d,J=7.8Hz,H-l’),3.78(lH,d, J= 12.0 HI H-6a’) and 3.68 (lH, dd, J= 12.0, 5.8 Hz, H6b’); EIMS m/z (rel. int.): 416 [M]’ (6), 398 [M -H,O]+ (lo), 380 [M-2H,O]+, 281, 254 [M-glucose+H]+ (15), 163,43 (100); 13C NMR 6 (ppm): 49.4 (C-l), 36.6 (C2), 74.6 (C-3), 38.7 (C-4), 75.5 (C-5), 128.8 (C-6), 145.1 (C7), 42.2 (C-8), 65.3 (C-9). 38.4 (C-lo), 30.6 (C-l 1), 21.7 (C12), 23.5 (C-13), 25.4 (C-14), 15.7 (C-15), 101.1 (C-l’), 74.8 (C-2’). 78.0 (C-3’), 71.7 (C-4’), 77.7 (C-5’) and 62.8 (C-6’). Erigeside B (2). C, zH,,06, amorphous powder. IR vi:; (cm-‘): 3150-3600 (OH) and 1630 (double bond); ‘HNMR6(ppm):5.44(lH,dt,J=l7.5,7.6H~H-2),5.36 (lH, dt, J= 17.5, 7.3 Hz, H-3). 4.26 (IH, d, J=7.6 Hz, Hl’), 3.89 (2H, d, J=7.6Hz, H-l), 3.67 (lH, dd, J=l2.1, 2.1 Hz, H-6a’), 3.52 (lH, dd, J= 12.1, 5.8 Hz H-6b’), 0.97 (3H, t, J = 7.2 Hz., H-6); EIMS m/z (rel. int.): 262 [M] + (2), 163 (15), 100 (5), 83 (60), 60 (70), 55 (95) and 41 (100); 13CNMR 6(ppm): 70.4(C-1), 134.5 (C-2), 126.6 (C-3), 28.7 (C-4), 21.5 (C-5), 14.6 (C-6), 104.2 (C-l’), 75.0 (C-2’), 78.0 (C-3’), 71.6 (C-4’), 77.6 (C-5’) and 62.7 (C-6’). Erigeside C (3). C,SH,,O,, (M-glucose+H, Found 198.0529, requires 198.0528), mp 159-161”. IR vi:: cn-‘: 3150-3550 (OH), 1695 (carbonyl), 1600 and 1510 (aromatic); ‘H NMR 6 (ppm): 7.39 (2H, s, H-2,6), 5.69 (lH, d, J =8.OHz,H-1’),3.86(lH,dd, J=l2.0, 1.6Hz,H-6a’),3.70
719
(lH, dd, J= 12.0, 1.6 Hz, H-6b’) and 3.88 (6H, s,-OMe); EIMS m/z (rel. int.): 360 [Ml’ (5), 198 [M-glucose +H]’ (lOO), 181 [198-OH]’ (50); 13CNMR 6 (ppm): 120.7 (C-l), 108.8 (C-2), 189.0 (C-3), 142.7 (C-4), 149.0 (C5), 108.8 (C-6), 166.8 (C-7), 56.9 (-OMe), 96.2 (C-l’), 74.1 (C-2’), 78.9 (C-3’), 71.2 (C-4’), 78.1 (C-5’) and 62.4 (C-6’). Betulabuside A (4). CL6HZB07 amorphous powder. IR vit;cm-‘: 3200-3550 (-OH), 1630 (double bond); ‘HNMR 6 (ppm): 5.90 (lH, dd, J= 17.4, 10.8 HI H-7), 5.45(1H,t,J=7.7H2,H-3),5.18(1H,dd,J=17.4,1.4Hz, H-8), 5.02 (IH, dd, J= 10.8, 1.4 HI H-8). 4.23 (lH, d, J =7.8Hz,H-1’),4.18(1H,d,J=11.5Hz,H-9a),4.02(1H, d,J=ll.5HcH-9b),3.83(lH,dd,J=l2.0,2.1 Hz,H-6a’), 3.66 (lH, dd, J=12.0, 5.6Hz, H-6b’), 2.06 (2H, t, J =7.9 Hz,H+, 1.51(2H,t, J=7.9 Hz,H-5), 1.71 (3H,s,H1) and 1.24 (3H, s, H-lo), EIMS m/z (rel. int.): 332 [M]’ (3), 315 [M-OH]’ (15), 163,152,107,93,85,71,55 and 43 (100); 13CNMR d (ppm): 14.1 (C-l), 132.8 (C-2). 130.1 (C-3), 23.4 (C-4), 42.8 (C-5), 73.7 (C-6), 146.1 (C-7), 112.1 (C-8), 75.9 (C-9), 27.6 (C-lo), 102.6 (C-l’), 75.0 (C-2’), 78.0 (C-3’), 71.6 (C-4’), 77.7 (C-5’) and 62.7 (C-6’). Erigeroside (5). C,,H,,Os, needles, mp 190-191”. IR vk:; cm-‘: 3000-3500 (OH), 1690 (carbonyl), 1605 (double bond); ‘H NMR 6 (ppm): 8.32 (lH, s, H-3), 8.10 (lH,d,J=5.5Hz,H-5),6.52(lH,d, J=5.5Hz,H-6),4.72 (lH,d,J=7.2Hz,H-1’),3.92(lH,dd,J=l2.0,2.lHz,H6a’). 3.65 (lH, a’d, J= 12.0, 5.8 Hz, H-6b’); EIMS m/z (rel. int.): 274 [M]’ (lo), 162 (30), 112 [M-glucose+H]’ (100); “CNMR 6 (ppm): 176.1 (C-l), 148.2 (C-2). 146.8 (C-3), 157.9 (C-5), 117.1 (C-6), 103.6 (C-l’), 74.7 (C-2’), 78.6 (C-3’), 71.3 (C-4’), 77.2 (C-5’) and 62.6 (C-6’).
REFERENCES
1. Zhang, R. W., Yang, S. Y. and Lin, Y. Y. (1981) Acta Pharm. Sin. 16, 68. 2. Pals, M., Fontaine, C., Laurent, D., Barre, S. L. and Guittet, E. (1987) Tetrahedron Letters 28, 1409. 3. Nyasse, B., Ghogmutin, R., Sondengam, B. L., Martin, M. T. and Bodo, B. (1988) Phytochemistry 27, 179. 4. Both, K. and Pedersen, Ch. (1983) Adv. Carbohydrate Chem. B&hem. 41.45. 5. Tschesche, R., Ciper, F. and Breitmaier, E. (1977) Chem. Ber. 110,3111. 6. Tori, K., Seo, S., Yoshimura, Y., Arita, H. and Tomita, Y. (1977) Tetrahedron Letters 179. 7. Seo, S., Tomita, Y., Tori, K. and Yoshimura, Y. (1978) J. Am. Chem. Sot. 100, 3331.
00314422(!M)EOO11-G
Phymhenuury, Vol. 34 No. 3. pp. 717.719. 1994 Cow&t c 1994 Elswicr Scicna Ltd Pnntcd I” Great Bntarn All rights rc~erwd 0031-9422.94 S7.00+000
A SESQUITERPENE AND OTHER CONSTITUENTS FROM ERIGERON
BRE VISCAPUS
JIANMINYUE, ZHONGWENLIN, DEZU WANG and HANDONGSUN+ Laboratory of Phytochemistry, Kunming Institute of Botany, Academia Sinica, Kunming, 650204, Yunnan, China (Receiued in revised
Key Word Index--Erigeron
form
14 December 1993)
breviscapns; Compositae; erigesides A, B and C.
Abstract-Three new constituent erigesides, A-C, as well as two known compounds, betulabuside A and erigeroside, have been isolated from Erigeron breoiscapus. The structures of the new compounds were established on the basis of spectral analysis.
INTRODUCTION
Erigeron breviscapus (Van) Hand.-Mau is a perennial herb, which grows abundantly in the Yunnan and Guangxi provinces of China. Erigeroside has been found previously in this plant [I]. We report here the isolation and structural elucidation of three new constituents, erigesides A (lb B (2) and C (3) along with two known compounds, betulabuside A (4) and erigeroside (S), from the butanol-soluble fraction of E. breviscapus. RESULTS AND DlSCUS!%ON
Erigeside A (I) was assigned the molecular formula Cz1HJ608 (HRMS). The ion of highest mass, [Ml’ observed at m/z 416 in the EIMS of 1 was shifted to m/z 417 [M + 11’ in the FABMS. Its IR spectrum showed the presence of hydroxyl groups (3150-3600 cm- *) and a carbon-carbon double bond (1634 cm- ‘). The t3C NMR pattern of 1 indicated the presence of a glucose moiety and a 15 carbon atom aglycone moiety. The 13C NMR spectrum of this aglycone moiety revealed four methyl groups, three secondary carbon atoms, five tertiary carbon atoms and three quatemary carbons. The ‘H NMR spectrum of 1 contained signals for an angular methyl group (61.04, 3H, s, H-14), a secondary methyl group (60.95, 3H, d, J=7.0 Hz, H-15). and an isopropyl chain (three signals, see Experimental) attached to the carbon-carbon double bond [2]. The ‘H and ’ 3C NMR spectral assignments (Experimental), based on ‘H-‘H COSY, NOSY, ‘H-13C correlation spectra and DEPT techniques, suggested that the aglycone moiety had a eudesmane skeleton. H-6 is responsible for the singlet signal at 6 5.47 (1H). The signals at 6 2.29 (1H, dd, .I = 14.9,5.8 Hz) and 1.50 (I H, d, J = 14.9 Hz) were assigned to H-8/? and H-8a, respectively. The signal at 64.15 (1H, d,
*Author to whom correspondence. should be addressed.
J=5.8 Hz) correlating with H-8p in the ‘H-‘HCOSY spectrum is typical of H-98 geminal with a hydroxyl group. The quaternary carbon signal at 675.5 in the “CNMR spectrum derives from the C-5 bearing a hydroxyl group [3]. The signal at 63.97 (1H, ddd, J = 14.8, 14.2,4.7 Hz) was attributed to the H-3a geminal with the glucose moiety, and assignment supported by the tertiary carbon signal at 674.6 (C-3) in the *%INMR spectrum. The most probable stereochemistry of carbons C-4, C-5 and C-IO was suggested by comparison of the ‘H NMR and 13C NMR data with those of the known compounds stylotelline [2] and a-carymobolol[3], and confirmed by the ‘H-‘H NOSY spectrum (Fig. 1). Thus, the coupling constants of protons associated with C-3 and C-9 and the ‘H-‘H NOSY spectrum (Fig. 1) established the relative configurations of these carbons. The ‘H NMR signal at 64.38 (IH, d, J=7.8 Hz) and the 13CNMR signal at 6101.7 are assignable to the l-position of the glucose moiety, suggesting the presence of /I-glucose [4]. The structure of erigeside A was thus assigned to be 1. Erigeside B (2), has a molecular formula C,,H,,O, based on the 13CNMR and MS data. Its IR spectrum indicated the presence of hydroxyl groups (3150-3600 cm-‘) and a carbon-carbon double bond (1630 cm-‘). The 400 MHz ‘H NMR spectrum of 2 showed the presence of a methyl group at 60.97 (3H, t, J = 7.2 Hz), two coupled signals at 65.44 (IH, dt, J = 17.5 Hz, 7.6 Hz) and 5.36 (lH, dt, .I= 17.5, 7.3 Hz) characteristic of -CH,-CH=CH-CH,-, and a signal at 63.95 (ZH, dd, J = 7.6, 1.5 Hz) indicative of protons geminal with an oxygen atom. The 13C NMR and ‘H NMR spectra revealed the presence of a /?-glucose moiety [4]; this was supported by the lose of 162 mass units from the [M]’ (m/z 262) to give a weak peak (m/z 100) and a strong peak (m/z 83). The 13CNMR spectrum also revealed the presence of six carbons in the aglycone moiety, a methyl (6 14.6). three methylenes (621.5, 28.8 and 70.4) and two methines (6126.6 and 134.5) in a double bond. 717
JMHUIN
718
YUF et al.
4
3
5
CH~OH
R= “;a OH
RO
Fig. 1.
On the basis of the above data and the i3CNMR assignments (Experimental), the structure of erigeside B was clearly established to be 2. Erigeside C (3), C, ,H,,O, e (HRMS). Its IR spectrum showed the presence of hydroxyl groups (3 150-3550 cm _ ‘), a carbonyl absorption band (1695cm-‘) and aromatic ring (1600 and 1510cm- I). The “C NMR spectrum of 3 indicated the presence of a glucose moiety and a nine carbon atom aglycone moiety; this was supported by the loss of a 162 mass unit from the CM]’ (m/z 360) to give the base peak (m/z 198). The appearance ofsix signals in the 13C NMR spectrum ofthe aglycone moiety corresponded to nine carbon atoms, indicating that the molecule must have a degree of symmetry in its structure. In the COLOC spectrum, the signal at 6 7.39 (ZH, s) correlated with the signals at 6 166.8 (C-7), 149.O(C-3 and C-5) 143.O(C-4) and 120.7 (C-l). The two methoxy groups were assigned to C-3 and C-5, and a hydroxyl group attached to C-4 was evident from examination of the i3CNMR and the COLOC spectra. The ‘H NMR signal at 65.69 (IH. d. J= 8.0 Hz) and the
i3C NMR signal at 696.2 were assigned to the I-position of the fi-glucose moiety, suggesting that the moiety was attached to C-7. The structure of erigeside C was thus elucidated to be 3. Erigeroside and batulabuside A were identified on the basis of spectral data and physical constants [l. 51. In a previous study [S], the structure of betulabuside A (4) was assigned by spectral analysis of its aglycone and tetraacetate betulabuside A. The ‘“CNMR signals assigned to C-9 of its aglycone and tetraacetate betulabuside A were those at 668.9 and 68.7, respectively. This seems unlikely since the 2-C of an aglycone moiety is generally deshielded (cu A57) on glucoside formation [6, 73. In our study, the C-9 of betuiabuside A was observed at 675.9. WC now report the spectral data and physical constants of betulabuside A.
EXPERIMENTAL
Mp: uncorr.; NMR: ‘H at 400 MHz, ‘-‘C at 100 MHz, CD,OD; FABMS and EIMS: ZAB-HS mass spectrometer. Plant material. Eriyeron hreviscapus (Van.) Hand.Mazz was collected at Kunming, Yunnan province, China. The species was authenticated by Prof. Wu ZhengYi, Kunming Institute of Botany, Academia Sinica, where a voucher specimen is deposited. Extraction and separation. The air-dried powdered whole plant (5 kg) was extracted ( x 3) with 95% EtOH at room temp. The extract was evapd to dryness under red. pres. and the residue (208 g) was dissolved in water (200ml). The aq. soln was partitioned with hexane, EtOAc and n-BuOH to give fractions H (20 g). E (51 g) and N (31 g). respectively.
Sesquiterpene
from Erigeron breuiscapus
Isolation. Fr. N (31 g) was chromatographed on a column of silica gel (300 g) eluting with CHCI, containing gradually increasing amounts of MeOH to give frs l-12. Frs 2 and 3 were combined and passed through a column of RP-8 silica gel with MeOH-Hz0 (3:2) as eluent to yield betulabuside A (41 mg). Frs 4-7 were combined and crystallized from EtOH to afford erigeroside (6.7 g). Frs 8- 10 were combined and chromatographed on an RP-8 silica gel column to afford erigeside A (52 mg) and erigeside B (27 mg). Recrystallization of fr. 11 from MeOH gave erigeside C (57 mg). Erigeside A (1). CZ1H360s (M-2H,O, Found: 380.2196, requires 380.2199), amorphous powder. IR YE: cm- ‘: 3150-3600 (-OH), 1634 (double bond); ‘H NMR 6 (ppm): 1.65 (IH, m, overlapped with H-4/?, Hla), 1.61 (lH, ddd, J= 14.0, 4.8, 2.7 Hz, H-l/?), 1.33 (lH, dddd, J= 14.8, 14.0, 14.0,4.8 Hz, H-2/?), 1.75 (lH, dddd, J = 14.0,4.8,4.7,2.7 Hz, H-2a), 3.97(1H,ddd,J= 14.8, 14.2, 4.7 Hz H-3a), 1.65 (lH, m, H-4/?), 5.47 (lH, s, H-6), 2.99 (lH, dd, J=l4.9, 5.8 Hz, H-8/?), 1.50 (lH, d, J=l4.9 Hz, H-8a), 4.15 (lH, d, J=5.8 Hz, H-9/?), 2.50 (lH, septet, J =6.9Hz,H-11),1.02(3H,d,J=6.9H~H-12),1.15(3H,d, J=6.9 Hz, H-13), 1.04 (3H, s, H-14). 0.95 (3H, d, J =7.0Hz,H-l5),4.38(1H,d,J=7.8Hz,H-l’),3.78(lH,d, J= 12.0 HI H-6a’) and 3.68 (lH, dd, J= 12.0, 5.8 Hz, H6b’); EIMS m/z (rel. int.): 416 [M]’ (6), 398 [M -H,O]+ (lo), 380 [M-2H,O]+, 281, 254 [M-glucose+H]+ (15), 163,43 (100); 13C NMR 6 (ppm): 49.4 (C-l), 36.6 (C2), 74.6 (C-3), 38.7 (C-4), 75.5 (C-5), 128.8 (C-6), 145.1 (C7), 42.2 (C-8), 65.3 (C-9). 38.4 (C-lo), 30.6 (C-l 1), 21.7 (C12), 23.5 (C-13), 25.4 (C-14), 15.7 (C-15), 101.1 (C-l’), 74.8 (C-2’). 78.0 (C-3’), 71.7 (C-4’), 77.7 (C-5’) and 62.8 (C-6’). Erigeside B (2). C, zH,,06, amorphous powder. IR vi:; (cm-‘): 3150-3600 (OH) and 1630 (double bond); ‘HNMR6(ppm):5.44(lH,dt,J=l7.5,7.6H~H-2),5.36 (lH, dt, J= 17.5, 7.3 Hz, H-3). 4.26 (IH, d, J=7.6 Hz, Hl’), 3.89 (2H, d, J=7.6Hz, H-l), 3.67 (lH, dd, J=l2.1, 2.1 Hz, H-6a’), 3.52 (lH, dd, J= 12.1, 5.8 Hz H-6b’), 0.97 (3H, t, J = 7.2 Hz., H-6); EIMS m/z (rel. int.): 262 [M] + (2), 163 (15), 100 (5), 83 (60), 60 (70), 55 (95) and 41 (100); 13CNMR 6(ppm): 70.4(C-1), 134.5 (C-2), 126.6 (C-3), 28.7 (C-4), 21.5 (C-5), 14.6 (C-6), 104.2 (C-l’), 75.0 (C-2’), 78.0 (C-3’), 71.6 (C-4’), 77.6 (C-5’) and 62.7 (C-6’). Erigeside C (3). C,SH,,O,, (M-glucose+H, Found 198.0529, requires 198.0528), mp 159-161”. IR vi:: cn-‘: 3150-3550 (OH), 1695 (carbonyl), 1600 and 1510 (aromatic); ‘H NMR 6 (ppm): 7.39 (2H, s, H-2,6), 5.69 (lH, d, J =8.OHz,H-1’),3.86(lH,dd, J=l2.0, 1.6Hz,H-6a’),3.70
719
(lH, dd, J= 12.0, 1.6 Hz, H-6b’) and 3.88 (6H, s,-OMe); EIMS m/z (rel. int.): 360 [Ml’ (5), 198 [M-glucose +H]’ (lOO), 181 [198-OH]’ (50); 13CNMR 6 (ppm): 120.7 (C-l), 108.8 (C-2), 189.0 (C-3), 142.7 (C-4), 149.0 (C5), 108.8 (C-6), 166.8 (C-7), 56.9 (-OMe), 96.2 (C-l’), 74.1 (C-2’), 78.9 (C-3’), 71.2 (C-4’), 78.1 (C-5’) and 62.4 (C-6’). Betulabuside A (4). CL6HZB07 amorphous powder. IR vit;cm-‘: 3200-3550 (-OH), 1630 (double bond); ‘HNMR 6 (ppm): 5.90 (lH, dd, J= 17.4, 10.8 HI H-7), 5.45(1H,t,J=7.7H2,H-3),5.18(1H,dd,J=17.4,1.4Hz, H-8), 5.02 (IH, dd, J= 10.8, 1.4 HI H-8). 4.23 (lH, d, J =7.8Hz,H-1’),4.18(1H,d,J=11.5Hz,H-9a),4.02(1H, d,J=ll.5HcH-9b),3.83(lH,dd,J=l2.0,2.1 Hz,H-6a’), 3.66 (lH, dd, J=12.0, 5.6Hz, H-6b’), 2.06 (2H, t, J =7.9 Hz,H+, 1.51(2H,t, J=7.9 Hz,H-5), 1.71 (3H,s,H1) and 1.24 (3H, s, H-lo), EIMS m/z (rel. int.): 332 [M]’ (3), 315 [M-OH]’ (15), 163,152,107,93,85,71,55 and 43 (100); 13CNMR d (ppm): 14.1 (C-l), 132.8 (C-2). 130.1 (C-3), 23.4 (C-4), 42.8 (C-5), 73.7 (C-6), 146.1 (C-7), 112.1 (C-8), 75.9 (C-9), 27.6 (C-lo), 102.6 (C-l’), 75.0 (C-2’), 78.0 (C-3’), 71.6 (C-4’), 77.7 (C-5’) and 62.7 (C-6’). Erigeroside (5). C,,H,,Os, needles, mp 190-191”. IR vk:; cm-‘: 3000-3500 (OH), 1690 (carbonyl), 1605 (double bond); ‘H NMR 6 (ppm): 8.32 (lH, s, H-3), 8.10 (lH,d,J=5.5Hz,H-5),6.52(lH,d, J=5.5Hz,H-6),4.72 (lH,d,J=7.2Hz,H-1’),3.92(lH,dd,J=l2.0,2.lHz,H6a’). 3.65 (lH, a’d, J= 12.0, 5.8 Hz, H-6b’); EIMS m/z (rel. int.): 274 [M]’ (lo), 162 (30), 112 [M-glucose+H]’ (100); “CNMR 6 (ppm): 176.1 (C-l), 148.2 (C-2). 146.8 (C-3), 157.9 (C-5), 117.1 (C-6), 103.6 (C-l’), 74.7 (C-2’), 78.6 (C-3’), 71.3 (C-4’), 77.2 (C-5’) and 62.6 (C-6’).
REFERENCES
1. Zhang, R. W., Yang, S. Y. and Lin, Y. Y. (1981) Acta Pharm. Sin. 16, 68. 2. Pals, M., Fontaine, C., Laurent, D., Barre, S. L. and Guittet, E. (1987) Tetrahedron Letters 28, 1409. 3. Nyasse, B., Ghogmutin, R., Sondengam, B. L., Martin, M. T. and Bodo, B. (1988) Phytochemistry 27, 179. 4. Both, K. and Pedersen, Ch. (1983) Adv. Carbohydrate Chem. B&hem. 41.45. 5. Tschesche, R., Ciper, F. and Breitmaier, E. (1977) Chem. Ber. 110,3111. 6. Tori, K., Seo, S., Yoshimura, Y., Arita, H. and Tomita, Y. (1977) Tetrahedron Letters 179. 7. Seo, S., Tomita, Y., Tori, K. and Yoshimura, Y. (1978) J. Am. Chem. Sot. 100, 3331.