Phyrochemistry, Vol. 31, No. 3, pp. 961-965, 1992 Printed m Great Britain.

Q

PHENYLETHANOID AND LIGNAN GLYCOSIDES VERBASCUM THAPSUS TSUTOMU

WARASHINA,

TOSHIO

MIYASE

and

AKIRA

003 1 -9422/92 $5.00 + 0.00 1992 Pcrgamon Press plc

FROM

UENO

School of Pharmaceutical Sciences, University of Shizuoka, Yada, 395, Shizuoka 422, Japan (Received 24 July 1991)

Key Word Index-Verbascum

thapsus; Scrophulariaceae; phenylethanoid

glycosides; l&an

glycosides.

Abstract-Verbascum thapsus afforded, in addition to three known phenylethanoid glycosides and four lignan ones, five new phenylethanoid glycosides and one new lignan glycoside. Structures of the compounds were elucidated by spectroscopic methods and chemical evidence.

INTRODUCTION

RESULTS AND DISCUSSION

In connection with a study on the constituents of some plants in the Scrophulariaceae, we have also investigated Verbascwm thapsus. The previous paper [l] described the isolation of iridoid glycosides from these plants and this paper described the isolation and structural elucidation of five new phenylethanoid glycosides and one new lignan glycoside in addition to seven known compounds.

A water extract of whole plants of V. thapsus afforded five new compounds and seven known ones (1 [2], 2 [3], 3 [4], 9-12 [S]) whose structures were elucidated by comparison of ‘H and 13CNMR with reported data. The 13CNMR spectrum of compound 4 showed two methylene carbon signals (636.3, 71.9), six aromatic carbon ones (6112.7, 117.0, 121.2, 132.7, 147.1, 147.3) and

OH

R’

R’

R’

RZ

1

Xyl

OH

OH

9

H

H

(7R,8S)

2

Api

OH

OH

10

H

H

(7S,

3

Api

OMe

OMe

11

OMe

H

4 !!

Xyl Xyl

OH OMe

OMe OMe

12

OMe

H

(7R, 8s) (7S, 8R)

6 7

API

OMe

OH

Glc

OMe

OMe

I3

H

G’c

G,c_o&/&o~Hz

o

R3

o&=$OH

HO v

OH Rha 8

961

(7R

8R)

8s)

962

T. WARASHINAet al.

one methoxyl carbon (656.4) in an aglycone moiety. The ‘HNMR spectrum of the aglycone moiety exhibited ABC-type signals in the aromatic proton region C66.75 (lH,d,J=2Hz),6.79(1H,d,J=8Hz),6.69(1H,dd,J=8, 2 Hz)] and that for a methoxyl group C63.81 (3H, s)]. In the difference NOE spectrum, this methoxyl group signal showed a NOE to the H-5 signal due to the aromatic proton C66.79 (lH, d, 5=8 Hz)]. Thus, this aglycone moiety was determined to be 3-hydroxy-4-methoxyphenethyl alcohol. Except for the aglycone moiety, the ‘H and 13C NMR spectra of 4 were similar to that of arenarioside (1). Compound 4 also showed three anomeric proton signals C64.24 (1 H, d, J = 8 Hz), 4.38 (lH, d, J =8 Hz), 5.18 (lH, d, 5=2 Hz)], which belonged to xylose, glucose and rhamnose, respectively, after considering the results of acid hydrolysis. Moreover, the ‘H NMR spectrum of 4 showed two tvans-olefinic proton signals C66.28 (lH, d, J= 16 Hz), 7.60 (lH, d, J= 16 Hz)] and ABC-type ones C66.82 (lH, d, 5=8 Hz), 6.96 (IH, dd, J = 8, 2 Hz) and 7.06 (1H, d. J = 2 Hz) J. These signals were assigned to caffeic acid ester and this acid moiety, which was afforded by acid hydrolysis of 4, was compared with an authentic sample and found to be identical by HPLC. The esterified position was determined to be at C-4 of glucose because, in the ‘H NMR spectrum of 4, an acylation shift was observed at H-4 of glucose C64.98 (lH, t, J =9 Hz)]; this chemical shift corresponded to that of arenarioside (1). In the 13C NMR spectrum, the C-3 and C-6 signals of glucose were shifted downfield corresponding with glycosylation shifts. Thus, rhamnose and xylose were attached to these positions. When the NOE spectrum was measured, a NOE was observed between the anomeric proton signal of xylose C64.24 (1H. d, J = 8 Hz)] and H-6 of glucose C63.58 (lH, dd, .I= 11.5, 6 Hz), 3.86 (lH, dd, J = 11.5,2.5 Hz)]. This suggested that xylose was attached to the C-6 position and rhamnose to C-3 of glucose, respectively. Compound 5 showed similar ‘H and 13C NMR spectra to arenarioside (1) and compound 4. However, two methoxyl signals were observed in both spectra cS56.4. 56.5; 63.80 (3H, s), 3.87 (3H, s)]. In the NOE spectrum, one methoxyl signal at 63.80 (3H, s) exhibited a NOE with H-5, one of the aromatic protons C66.82 (lH, d, J = 8.5 Hz)] in the aglycone moiety, and another signal at 63.87 (3H, s) did with H-2 cS7.19 (lH, d, J= 1.5 Hz)] in the ester moiety. These suggested that the aglycone moiety of 5 is 3-hydroxy-4-methoxyphenethyl alcohol and that the ester moiety was ferulic acid; this was confirmed by comparison of the reaction mixtures afforded by acid hydrolysis of 5 with the corresponding authentic materials on HPLC. Compound 5 also showed three anomeric signals in its NMR spectra [S 104.1, 103.0, 105.3;64.38(1H,d,J=8Hz),5.20(1H,d,J=1.5Hz),4.24 (lH, d, J= 8 Hz)], which belonged to glucose, rhamnose and xylose, respectively. Comparison with the NMR spectra of arenarioside (1) and 4, enabled the position of attachment of these sugars to be determined. The ‘H and 13CNMR spectra of 6 were similar to those of forsythoside B (2) and leucosceptoside B (3), but only one methoxyl group signal was observed in each spectrum cS56.4; 63.88 (3H, s)]. In the ‘HNMR spectrum, this signal appeared at lower field than a methoxyl signal which was attached to an aromatic carbon in the aglycone moiety. Thus, this methoxyl group was attached to an aromatic one in the ester moiety, and the attached position was assigned to C-3 of the aromatic

carbon by comparison of its 13CNMR spectrum with that of leucosceptoside B (3). With regard to the sugar moiety, three anomeric signals were assigned to glucose, rhamnose and apiose at 64.37 (lH, d, J= 8 Hz), 5.19 (lH, d, J = 1.5 Hz) and 4.9 1 (1 H, d, J = 2 Hz), respectively, in the ‘HNMR spectrum. According to a ‘H and 13C NMR comparison between compounds 6 and 2 and 3, rhamnose was attached to C-3, apiose to C-6 and ferulic acid to C-4 of glucose, respectively. Compound 7 had a similar NMR spectrum to 5. It exhibited signals for 3-hydroxy-4-methoxyphenethyl alcohol, ferulic acid ester, glucose and rhamnose. However, signals for another glucose moiety were observed instead of those for xylose. In the 13C NMR spectrum of 7, glycosylation shifts were seen at C-3 (681.3) and C-6 Table 1. ‘%NMR

spectral data of (67.80 MHz in CD,OD)

compounds

4-8

C

4

5

6

I

8

OMe

71.9” 36.3 132.7 117.0 147.lb 147.3b 112.7 121.2 56.4

72.0” 36.5 132.9 117.1 147.3b 147.5” 112.9 121.2 56.4’

720 36.6 131.4 117.1 144.7 146.1 116.3 121.3 --

72.0” 36.4 132.7 117.0 147.1b 147.3b 112.8 121.2 56.4

72.2” 36.7 131.3 117.0 144.7 146.1 116.4 121.2 -

Sugar moiety inner Glc 1 2 3 4 5 6

103.9 75.8 81.6 70.3’ 74.6 69.1

104.1 76.0 81.5 70.4 74.8 69.3

104.2 76.1 81.4 70.9 74.6 68.4

104.0 76.0 81.3 70.5 74.6 69.2

104.4 75.4b 84.0 70.0 75.7b 64.8

Rham 1 2 3 4 5 6

102.9 72.0” 72.1” 73.5 70.3 18.4

103.0 72.2’ 72.3” 73.7 70.5 18.4

103.1 72.3’ 72.4’ 73.7 70.4 18.4

102.9 72.1” 72.2’ 73.6 70.5 18.4

103.4 72.3’ 72.5” 74.0 70.5 17.9

(XYQ 105.0 74.5 77.3 70.9’ 66.7

(XY~) 105.3 74.8 77.5 71.0 66.8

(Api) 111.0 78.1 80.6 75.1 65.6

(Glc) 104.5 74.9 77.7 71.3 77.7 62.5

(Gk) 102.7 74.8 78.3 71.3 77.5 62.4

168.3 115.3 148.1 127.5 114.5 149.6 146.6 116.5 123.2

168.3 115.0 148.1 127.6 111.8 150.8 149.3 116.5 124.4 56.5’

168.1 115.2 147.9 127.6 111.7 150.8 149.4 116.5 124.4 56.4

168.4 115.0 148.0 127.5 111.8 150.7 149.2 116.5 124.3 56.4

168.6 115.8 148.5 131.0 117.0 148.9’ 146.4’ 118.1 122.4

Aglycone moiety ; 1 2 3 4 5 6

Ester moiety ;I Y 1’ 2’ 3’ 4 5’ 6 OMe’ “-‘Assignments

may be interchanged in each column.

t 2 3 4 4‘ 5 5’ 6 6’

2 3 4 5 6

m m E(7.5) d (2) d (8) dd (8, 2) s

IH, lH, lH, lH,

d (8) dd (9, 8) t (9) m

6.28 7.60 7.06 6.82 6.96 -

lH, lH, lH, lH, lH,

d (16) d (16) d (2) d (8) dd (8, 2)

3.13 lH, dd (11, 10) 3.83 lH, dd (11, 5.5) _. -

(XYV 4.24 lH, 3.21 lH, 3.30 lH, 3.46 lH, -

m d (6)

d (2) dd (3,2) dd (9.5, 3)

t (9) m dd (11.5,6) dd (11.5, 2.5)

lH, d (8) IH, t (8) *

lH, lH, 2H, lH, lH, lH, 3H,

5.18 lH, 3.98 IH, 3.58 lH, 3.31 * 3.55 lH, 1.09 3H,

4.38 3.40 3.80 4.98 3.74 3.58 3.86

3.74 4.05 2.82 6.75 6.79 6.69 3.81

4

lH, lH, lH, lH, lH, 3H,

5.20 3.93 3.58 3.29 3.57 1.10 d (8) dd (8.5, 8) t (8.5) m

d (1.5) dd (3.5, 1.5) dd (9.5, 3.5) t (9.5) m d (6)

dd (1 l.S, 6) dd (11.5, 2)

t (9)

d (8) t (8)

m m t (7.5) d (1.5) d (8) dd (8, 1.5) s

6.38 7.66 7.19 6.82 7.09 3.87

lH, lH, lH, iH, lH, 3H,

d (16) d (16) d (1.5) d (8.5) dd (8.5, 1.5) s

3.15 lH, dd (11.5, 10) 3.83 lH, dd (11.5, 5.5) .-

(XYlI 4.24 lH, 3.21 lH, 3.29 lH, 3.47 lH, -

lH, lH, * lH, * lH, lH,

lH, lH, 2H, lH, lH, lH, 3H,

4.38 3.41 3.82 4.98 3.72 3.59 3.87

3.72 4.04 2.82 6.75 6.82 6.69 3.80

5

*Obscured by other signals; couplings could not be accurately determined.

; 5 6 OMe

B

Ester moiety

R&n1

Sugar moiety inner Glc 1 2 3 4 5 6 6

; 2 S 6 OMe

Agiycone moiety u.

H

IH, lH, lH, lH, * lH, lH,

lH, lH, 2H, lH, lH, lH,

d (6)

m

d (1.5) dd (3.5, 1.5) dd (9.5, 3.5) t (9.5)

dd (11,6) dd (11, 2)

d (8) t (8) t (8.5) t (8.5)

d (2) d (8) dd (8, 2)

m

m m

6.37 7.66 7.20 6.81 7.08 3.88

-

lH, lH, lH, IH, IH, 3H,

d (16) d (16) d (1.5) d (8) dd (8, 1.5) s

3.73 IH, d (9.5) 3.92 IH, d (9.5) 3.53 2H, s -

f&i) 4.91 lH, d (2) 3.87 lH, d (2) -

5.19 lH, 3.91 iH, 3.57 lH, 3.29 lH, 3.57 lH, 1.10 3H,

4.37 3.39 3.80 4.94 3.70 3.50 3.87

3.70 4.00 2.78 6.69 6.68 6.57 -

6

-

IH, lH, IH, lH, lH, !H, lH,

1H, lH, 2H, lH, lH, 1H, 3H,

* * 2H, IH, lH, lH,

d (1.5) dd (3, 1.5) dd (9.5, 3) t (9.5) m d (6.5)

dd (11.5, 6.5) dd (11.5, 2)

m

t (8.5) t (8.5)

d (8)

t (7.5) d (2) d (8) dd (8,2)

6.38 7.67 7.19 6.82 7.08 3.88

lH, lH, lH, tH, lH, 3H,

d (16) d (16) d (2) d (8) dd (8, 2) s

6.37 7.58 7.10 7.18 6.94 -

lH, lH, lH, lH, lH,

d (16) d (16) d (2) d (8) dd (8, 2)

3.73 (lH, dd (11.5,6.5) 3.92 (lH, dd (11.5, 2.5)

3.65 lH, dd (12, 5.5) 3.83 lH, dd (12, 5.5)

-

fGlc) 4.88 1H, d (8) 3.53 lH, t (8) 3.43 lH, t (8) 3.40 1H, t (8.5)

5.17 lH, 3.96 lH, 3.71 lH, 3.40 lH, 3.99 lH, 1.25 3H,

4.34 IH, 3.34 * 3.54 lH, 3.50 lH, 3.49 lH, 4.35 iH, 4.53 lH,

3.72 3.95 2.79 6.68 6.64 6.54 -

3.57 lH, m -

d (8) t (8) t (8.5) t (8.5)

d (6)

m

d (1.5) dd (3, 1.5) dd (9.5, 3)

dd (11.5, 5.5) dd (11.5, 2.5)

m

d (8) t (8) t (8.5) t (8.5)

m m t (7.5) d (2) d (8) dd (8, 2) s

8

3.22 lH, m -

(Gfc) 4.31 lH, 3.21 lH, 3.35 lH, 3.28 lH, -

5.20 lH, 3.93 1H, 3.58 lH, 3.31 * 3.58 lH, 1.11 3H,

4.39 3.41 3.82 5.01 3.76 3.65 3.94

3.76 4.04 2.82 6.75 6.82 6.69 3.81

7

Table 2. ‘H NMR spectral data af compounds 4-8 (SO0 MHz in CD,OD)

964

T. WARASHINAet ul.

(669.2) of the inner glucose, and the rhamonse

signals were almost identical to those of 4-6, which suggested that the terminal glucose was attached to the C-6 position of the inner glucose. From its NMR spectrum, 8 possesses 3,4-dihydroxyphenethyl alcohol, two glucoses, rhamnose and cinnamic acid moieties. These were confirmed by acid hydrolysis and comparison with authentic materials and consequently, this derivative was determined to be a caffeic acid ester. Because in the ‘HNMR spectrum, an acylation shift was observed at H-6 of the inner glucose, whose signal was shifted downfield to 64.35 (lH, dd, J = 11.5 Hz, 6.5 Hz) and 4.53 (lH, dd, J= 11.5, 2 Hz), this ester chain was combined with C-6 of the inner glucose. The anomeric carbon signal of the other glucose was at 6102.7 which existed 1.8 ppm upfield from that of the terminal glucose in compound 7. In the NOE spectrum, irradiation of the signal due to this anomeric signal caused a NOE to the one due to H-5 of caffeic acid ester. Based on the above evidence, this glucose is thus attachTable 3. ‘H and ‘aCNMR

ed to C-4 of caffeic acid ester and the structure of compound 8 was elucidated as shown. Compound 13 is a lignan glycoside whose NMR spectra were similar to those of dehydrodiconiferyl glucosides E (9) and D (10) [S]. In the NMR spectrum, two anomeric signals were observed [S 104.2, 102.7; 64.37 (lH, d, J = 8 Hz), 4.88 (lH, d, J = 8 Hz)] and acid hydrolysis of 13 suggested that these signals belonged to two glucoses, respectively. One glucose was attached to the C-9 position of the aglycone, the other to C-4 of the aromatic moiety in the aglycone, because this anomeric carbon signal occurred at a slightly higher held (S 102.7) and a NOE was observed between this signal C64.88 (lH, d, J =8Hz)] and the signal due to H-5 C67.13 (lH, d, J = 8 Hz)] in the aglycone moiety. The absolute configurations of the C-7 and C-8 positions were determined by CD where a negative Cotton effect was observed at ca 280 nm. This data was compared with those of dehydrodiconuferyl glucosides E (9) and G (11) [S], and these configurations were thus determined to be 7R and 88.

spectral data of compound

13 (500 and 67.8 MHz, in

CD,OD) H

13

Aglycone moiety 2 5 6 7 8 9a 9B OMe 2 6’ 7 8’ 9’ OMe’ Sugar moiety Glc 1 2 3 4 5 6a 68 Glc’ 1 2 3 4 5 6a 68

7.08 7.13 6.97 5.67 3.64 3.91 4.12 3.84 6.94 7.03 6.53 6.23 4.19 3.88

lH, lH, iH, lH, * * 1H. 3H. lH, lH, lH, (lH, 2H, 3H,

d (2) d (8) dd (8, 2) d (6)

4.37 3.24 3.40 3.24 3.30 3.67 3.82 4.88 3.49 3.40 b

IH, lH, * 1H. *c 1H. *d IH, lH, *

d (8) t (8)

dd (9.5, 8) sa br s br s

dt (16, 1.5) dt (16, 5.5) dd (5.5, 1.5) sa

t (8)b dd (11.5, 5) d (8) t (8)

3.39 *c 3.67 lH, dd (11.5, 5) 3.87 *’

C

13

Aglycone moiety 1 2 3 4 5 6 7 8 9 OMe 1’ 2’ 3’ 4 5’ 6 7’ 8’ 9 OMe’

137.9 111.4 150.9 147.6 117.9 119.5 89.0 52.8 72.2 56.8 129.8 112.2 145.5 149.1 132.8 116.7 131.9 127.7 63.8 56.8

Sugar moiety Glc 1 2 3 4 5 6 Glc’ 1 2 3 4 5 6

104.2 75.1* 78.0” 71.6’ 78.2 62.7d 102.7 74.9” 47.9b 71.3’ 78.2 62.4d

a-dAsignment may be interchanged. *Obscured by other signals; couplings could not be accurately determined. --Signal could not be determined.

Phenylethanoid

and lignan glycosides from Verbascum thapsus

EXPERIMENTAL

‘H and 13C NMR spectra were recorded at 500 MHz, and 67.8 MHz, respectively. TMS was used as int. standard. Plant material. Verbuscum thupsus L. was cultivated in the botanical garden and harvested on August 1990 in Shizuoka, Japan and identified by Prof. A. Ueno (University of Shizuoka). Extraction and isolation. Fr. whole plants of Y. thapsus (6.6 kg) were extracted twice with H,O. The extract was passed through a Mitsubishi Diaion HP-20 column and the MeOH eluate coned under red. pres. The residue (80.7 g) was rechromatographed on a Toyopeal HW-4UC column using H,O and MeOH as eluents. The H,O eluate consisted of three frs and the last one (23.5 g) was rechromatographed on a silica gel column using CHCI,-MeOH and semi-prep. HPLC [ODS and PhA: MeOH-H,O (9: 11-7: 13), MeCN-H,O (3: 17-7:33)] to give compounds I (146 mg), 2 (27 mg), 3 (26 mg), 4 (50 mg), 5 (38 mg), 6 (52 rngb 7 (44 mg), 8 (6 mg), 9 (10 mg),lO (4 mg), 11 (16 mg), 12 (14 mg) and 13 (6 mg). Compound 4. Amorphous powder. [a];* -80.8” (MeOH; c 0.6). Calcd. for C35b60, 9 .2H,O: C, 52.11; H, 6.25; found: C, 52.21, H, 6.23. UV n:z” nm (loge): 218 (4.31), 233 (sh), 248 (sh), 290 (sh), 331 (4.26). FAB-MS m/r: 793 [M+NaJ+, 771 [M +Hl +. ‘H and 13CNMR in Tables 1 and 2. Compound 5. Amorphous powder. [a]g2 -67.4” (MeOH; ~0.46). Calc. for C36H08019 .3H,O: C, 51.55, H, 6.49; found: C, 51.82, H, 6.39. UV n:yH nm (loge): 219 (4.34), 232 (sh), 288 (4.14), 3OO(sh),330 (4.36). FAB-MS m/z: 807 [M +Na]+, 785 [M +HJ + . ‘H and 13CNMR in Tables 1 and 2. Compound 6. Amorphous powder. [a]:: -67.3” (MeOH; c 1.10). Calcd. for C35H46019 . H20: C, 53.30, H, 6.13; found: C, 53.03, H, 6.21. UV A$:” nm (log 81 218 (4.31), 231 (sh), 290 (4.13X 328 (4.30). FAB-MS m/z: 793 [M+Na]+, ‘H and 13CNMR in Tables 1 and 2. Compound 7. Amorphous powder. [a]:: -79.2” (MeOH; C 0.84). Calcd. for C37H5*O** -H,O: C, 53.36, H, 6.29; found: C, 53.11, H, 6.38. UV 1::” nm (logs): 218 (4.31), 231 (sh), 289 (sh), 300 (sh), 328 (4.33). FAB-MS m/z: 837 [M-+Na]+, 815 [M +Hl +. ‘H and lsC NMR in Tables 1 and 2. Compound 8. Amorphous powder. [ol]iz -64-2” (MeOH; c 0.60). Calcd. for C35H460a0 - 7/2H,O: C, 49.46, H, 6.28; found: C, 49.54, H, 5.95. UV A:::” nm (logs): 216 (sh), 229 (sh), 289 (4.24),322 (4.17). FAB-MS m/z: 787 [M +Na]+, 809 CM +H]+; lH and lACNMR in Tables 1 and 2. Compound 13. Amorphous powder. [a]:: - 18.1” (MeOH, C0.54). Calcd. for C3*H42O16.5/2H,O: C, 52.82, H, 6.51; found: C, 53.08, H, 6.30. UV n”,z” nm (log&): 277 (4.18), [e] (nm):

465

+ 10300 (281), + 6590 (265). FAB-MS m/z: 705 [M + Na]+, 683

CM+W +. lH and 13CNMR in Table 3.

Acid hydrolysis ofcompounds 4-8 and 13. Compounds 4-8 (cu 1 mg) were refluxed in AcCl--MeOH (1: 20) (1 ml) for 1 hr. After being taken to dryness, the reaction mixt. was partitioned between EtOAc and HzO. The EtOAc layer was coned to dryness and the residue anaIysed by HPLC and comparison with authentic materials. Conditions: column; YMC R-ODS. Flow rate; 1.3 rnlmin- *. 10% MeCN, R, (min); 3,4_dihydroxyphenethyl alcohol 5.8, 3-hydroxy-4-methoxyphenethyl alcohol 17.6; 30% MeCN, R, (min); Me caReate 8.8, Me ferulate 17.4. The H,O layer was also coned to dryness and each residue in 5% H,SO, (2 drops) was heated at 100” for 1 hr; compound 13 (cu 0.1 mg) was also treated in the same method. The soln was passed through an Amberlite IR-45 column and the eluate coned to give a residue which was reduced witb NaBH, (cu 1 mg) for 1 hr at room temp. The reaction mixt. was passed through an Amberlite IR-120 column and the eluate coned to dryness. Boric acid was removed by co-distillation with MeOH and the residue acetylated with A@-pyridine (1 drop each) at 100” for 1 hr. The reagents were evapd in uucuo. From each glycoside, the acetates of glucitol, rhamnitol and xylitol were detected by GC. Conditions: column; Supelco SP-2380 capilfary column (0.25 mm x 30 m). Column temp.; 250”. carrier gas N,. R, (min); glucitol acetate 11.2, rhamnitol acetate 4.9 xylitol 7.3 min). In addition, to confirm apiose, compound 6 (ca 0.1 mg) in 1% H,SO, (2 drops) was heated at 100” for 5 min. The reaction mixt. was then treated by the same method as described above. Conditions: column temp.; 250”, R, (min); apinitol acetate 3.0. Acknowledgement-

We thank the staff of the Central Analytical Laboratory of this school for measurement of MS.

REFERENCES

1. Warashina, T. Miyase, T. and Ueno, A. (1992) Chem. Pharm. Bull. (in press). 2. Andary, C., Privat, G., Wyide, R. and Heitz, A. (1985) J. Nut. Prod. 48, 778.

3. Endo, K., Takahashl, K., Abe, T. and Hikino, H. (1982) Hetmocycles 19, 261. 4. Miyase, T., Ueno, A., Noro, T., Kuroyanagi, M., Fukushima, S., Akiyama, T. and Takemoto, T (1982) Chem. Phurm. ButI. 30, 2732.

5. Binns, A. N., Chen, R. H., Wood, H. N. and Lynn, D. G. (1987) Proc. NutI Acud SCI. USA 84, 980.

Phenylethanoid and lignan glycosides from Verbascum thapsus.

Verbascum thapsus afforded, in addition to three known phenylethanoid glycosides and four lignan ones, five new phenylethanoid glycosides and one new ...
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