Phy~~c~m~y, Vol. 31, No. 4, pp. 1391-1394, 1992 Priniedin Great Britain.
COMPLEX
FLAVONOL
0031-9&I/92 ~S.~+O.~ PergamonPress plc
GLYCOSIDES FROM THE LEAVES GINKGO BILOBA
ANDREAS HAS~ER, GIA~-A~DR~ Department
OF
GROSS,* BEAT MEIER and C&TO STICHER
of Pharmacy, Swiss Federal Institute of Technology (ETH) Zurich, (38-8092 Ziirich, Switzerland; Research Centre, Vers-chez-1~-3lanc~ Post O&e Box 44, CH-1000 Lausanne 26, Switzerland
*Nest=
Ltd,
(Received in revisedform 12 September 1991) Key Word In&x-Girt&o b~Zo~~ Ginkgoaceae; flavonoid glycosides; kaempferoi ?I-@“-glucosylJrham~oside; kaempferol 3-[2”-6”‘-fp-(7”“-g(ucosyl)coumaroyl) quercetin 3-[2”-glucosyl]rhamnoside; quercetin 3-[2”-6’“-(p~7”“-glucosyl~~umaroyl~glucosyl]rhamnoside; quercetin 3-~~-~-p-~umaroyl~ glucosyllrba~osyl-7-glucoside.
Abstract-Five new Aavonol gfycosides were isolated from the leaves of Ginkgo ~jlo~~and their structures determined by spectroscopy and hydrolysis experiments.
At the present time Ginkgo bilabu L. is one of the most popular medicinal plants. Extracts of the leaves of G~~~~o bitoba increase peripheral and cerebral blood flow [l]. Such extracts contain ffavonoids and ginkgolides as the pharmacologi~lly active compounds. We previously reported the isolation of 21 flavonoids from the leaves of Ginkgo &l&u [23 and three methods for tbe quantitative and qualitative analysis of the gavonoid pattern by HPLC [24]. This report deals with the structural elucidation of five new flavonol glycosides (1-S). RJZWJTg AND
DISCUSSION
Dried leaves of Gj~~~o ~~~o~u were powdered and extracted. Compounds l-5 were isolated from Iyophilized methanol extract as reported in detail elsewhere [2].
R’:
Fe
F?:
2
H
gk:
H
4
OH
gk:
H
5
OH
H
gic
HO
OH
R: 1
H
3
OH
Compounds 1 and 3 had HPLC R,s close to known flavonoid ~glyc~ides, e.g. kaempferol 3-~tinoside and rutin (R, 1 5.5 min, kaempferol 3-rutinoside 4.2 mm, 3 3.5 min, rutin 2.7 min) both occurring in the leaves of Gecko ~iZo~u[2]. The FAB mass spectrum of 1 displayed a molecular ion peak at m/z 595 [M +H]* and an agfycone ion peak at m/z 287 [kaempferol+H]+, the spectrum of 3 showed a molecular ion peak at m/z 611 [M +H]” and an aglycone ion peak at m/z 303 [quercetin + N] ‘. Acid hydrolysis of 1 and 3 released glucose and rhamnose, identj~ed by TLC; the aglycones co-migrated with kaempferol and quercetin, respectively. They were both substituted at position 3 as indicated by their UV spectra on addition of diagnostic shift reagents [S, 61. 1391
1392
A. HASLERet at.
Table 1. 13C NMR data (75 MHz, CD,OD) 1
C
Flavonol nucleus 159.4 s 2 135.5 s 3 179.6 s 4 163.2 s 5 100.0 d 6 166.0 s 7 94.9 d 8 158.6 s 9 106.0 s 10 122.6 s 1’ 132.0 d 2 116.6 d 3’ 161.7 s 4 116.6 d 5’ 132.0 d 6 Rharnnose 102.6 d I” 82.7 d 2” 71.8 d 3” 13.5 d 4” 72.0 d 5” 17.7 q 6” Glucose 107.1 d 1I,, 75.4 d 21,1 71.9 d 3 I,?
4” 5”
71.0 d
78.0 d 62.4 t 6 (11 Coumaric acid 1”” 2”” 3111, 4”’ 5,r,, 6 ,I,! 7,.=2.2 Hz, J 6”“A,5”,A= 11.9 Hz, H-61;), 4.97 (1H, d, J = 7.0 Hz, ‘H-Y), 5.79 (lH, d, H-l”), 6.03 (lH, d, 5=16.OHz, H-Y), 6.f3 (IH, d, J =2.0Hz, H-6), 6.16 (lH, d, J=20Hz, H-S), 6.93 (IH, d, J = 8.6 Hz, H-S), 6.95 (2H, d, J = 8.8 Hz., H-6”” and H-8”“), 7.27 (3H, m, H-6’, H-S”’ and H-9”“), 7.31 (lH, d, J,,,& = 1.9 Hz, H-2’), 7.41 (iH, d, J=16.OI-k, H-3”“). For “CNMR (75SMHz, CD,OD) see Table 1.
1394
A. HASLERet al.
UV FAB-MS: mjz 919 [M+H]*, 303 [aglycone~~~+. I:$‘” nm: 256,26Ssh, 3OOsh.3 14,36Osh, N&Me 260,363; AICI, 276,297sh. 311sh, 435; AKLHCI 276.294sh. 313.398: NaOAc 2#0,314,342; NaoAc~H,Bcj, 261,316,368. tiv Lkurn after partial alkaline hydrolysis: 257, 264sh, 346; NaOMe 262, 396; AK& 273, 30% 324, 428; AR&-HCl 270, 298sh, 358, 394; NaOAc 256,396; NaOAc-HsBO, 260,317. ‘H NMR (300 MHz, CD&D) 6: 1.08 (3H, d. J -6.2 Hz, H-6”), 3.26357 (9H, m, sugar t* protons), 3.74 (IH, dd, Js,,,*,=9.5 H7, J 5r,.6., =6.2 Hz, H-5 ), 3.76 (IN, ABX, Jb.v.,a ,...==5.5 Hz, J, I.,>, n 6.,/,,,,=11.9 Hz, H&,..:9.8 Hz, H-3”), 3.96 @;;“‘),3.89 (IH, dd, J s.,,.,=3SHz, ,’ (1% ABX, J,..,.,,_,p..,, a=f1.9 Hz, H-6r). 4.08 (1H. ABX, J,...a,s.,, =6.6 Hz, _3s”‘n6,,.Ac Il.9 Hz, H-5;;‘), 4.34 (IX, dd, J,.,,,,.=3.5 Hz, H-2”), 4.40 (IH, d, J==7.8 Hz, H-l”‘), 4.52 (IH, ABX, J,...,,,,..=2.1 Hz, J6.’ A 6”,s= 11.9 Hz, H-6;). 5.03 (iH, d, .I=7.1 Hz,H-l”“‘),5.72(1H,~,H-l”),6.~(tH,d,J=16.0Hz,H2”“), 6.41 (1H, d, J=2.0Hz, H-6), 6.50 (1H, d, .l=2.OHz, H-8), 6.66 (ZH, d, J= 8.5 Hz. H-6”” and H-8”“), 6.90 (1 H. d, J = 8.4 Hz, H-5’), 7.17 (2H, d, 6x8.5 Hz, H-S”’ and H-s”“), 7.23 (1H, dd, J ,,.~,‘1.9Hz,J6..~.=8.4Hz,H-6’).7.33(1H,d,Jz,.6.=1.9Hz, H-2’), 7.40(1H, d, J= 16.0 Hz, H-3”“). For ‘Y?NMR (75.5 MHz, CD&D) see Table J. ~ckna~~edge~nts-
-Finauc~ai support by Zeller ACi Romanshorn, Switzerland is gratefully acknowledged, We also thank
Dr A. Wright (Department of Pharmacy, ETH-Zilch)
for the NMR measurements and R. Hiifliger (Depa~ment of Chemistry, ETH-Zurich) for FAB-MS measurements,
1. F~nfgeld, E. W. (ed.) (1988) R&n, G~~kgu b&&a, Recent Results in ~~rrnac~~og~ and in C&tic. Springer, Berlin.
2. Hasler, A. (1990) Thesis, E’I’H Zurich, No. 9353. Zurich, Switzerland. 3. Hasler, A., M&r, B. and Sticher, 0. (1990) J. C~~o~~ro~~. 508, 236. 4. Ha&r, A., Meier, B. and Sticher, 0. (1990) Schweiz. Apotheker Zeit. lzs, 341. 5. Mabry, T. J., Markb~, K. R. and Thomas, M. B. (1970) The Systematic ident~~cati~~ o~~lu~~~~ids. Springer, Berlin. 6. Markham, K. R. (1982) Techniques of ~~a~~un~~d ~dentz~cffrjon. Academic Press, London. 7. Bacon, J. D. and Mabry T, J. (1976) Rea. ~ti~ou?~. Quim, 7, 83. 8. AgrawaI, P. K. (~989) Carbon-13 NMR of ~~av~~~~d~. Elsener, Amsterdam.
COMPLEX
FLAVONOL
0031-9&I/92 ~S.~+O.~ PergamonPress plc
GLYCOSIDES FROM THE LEAVES GINKGO BILOBA
ANDREAS HAS~ER, GIA~-A~DR~ Department
OF
GROSS,* BEAT MEIER and C&TO STICHER
of Pharmacy, Swiss Federal Institute of Technology (ETH) Zurich, (38-8092 Ziirich, Switzerland; Research Centre, Vers-chez-1~-3lanc~ Post O&e Box 44, CH-1000 Lausanne 26, Switzerland
*Nest=
Ltd,
(Received in revisedform 12 September 1991) Key Word In&x-Girt&o b~Zo~~ Ginkgoaceae; flavonoid glycosides; kaempferoi ?I-@“-glucosylJrham~oside; kaempferol 3-[2”-6”‘-fp-(7”“-g(ucosyl)coumaroyl) quercetin 3-[2”-glucosyl]rhamnoside; quercetin 3-[2”-6’“-(p~7”“-glucosyl~~umaroyl~glucosyl]rhamnoside; quercetin 3-~~-~-p-~umaroyl~ glucosyllrba~osyl-7-glucoside.
Abstract-Five new Aavonol gfycosides were isolated from the leaves of Ginkgo ~jlo~~and their structures determined by spectroscopy and hydrolysis experiments.
At the present time Ginkgo bilabu L. is one of the most popular medicinal plants. Extracts of the leaves of G~~~~o bitoba increase peripheral and cerebral blood flow [l]. Such extracts contain ffavonoids and ginkgolides as the pharmacologi~lly active compounds. We previously reported the isolation of 21 flavonoids from the leaves of Ginkgo &l&u [23 and three methods for tbe quantitative and qualitative analysis of the gavonoid pattern by HPLC [24]. This report deals with the structural elucidation of five new flavonol glycosides (1-S). RJZWJTg AND
DISCUSSION
Dried leaves of Gj~~~o ~~~o~u were powdered and extracted. Compounds l-5 were isolated from Iyophilized methanol extract as reported in detail elsewhere [2].
R’:
Fe
F?:
2
H
gk:
H
4
OH
gk:
H
5
OH
H
gic
HO
OH
R: 1
H
3
OH
Compounds 1 and 3 had HPLC R,s close to known flavonoid ~glyc~ides, e.g. kaempferol 3-~tinoside and rutin (R, 1 5.5 min, kaempferol 3-rutinoside 4.2 mm, 3 3.5 min, rutin 2.7 min) both occurring in the leaves of Gecko ~iZo~u[2]. The FAB mass spectrum of 1 displayed a molecular ion peak at m/z 595 [M +H]* and an agfycone ion peak at m/z 287 [kaempferol+H]+, the spectrum of 3 showed a molecular ion peak at m/z 611 [M +H]” and an aglycone ion peak at m/z 303 [quercetin + N] ‘. Acid hydrolysis of 1 and 3 released glucose and rhamnose, identj~ed by TLC; the aglycones co-migrated with kaempferol and quercetin, respectively. They were both substituted at position 3 as indicated by their UV spectra on addition of diagnostic shift reagents [S, 61. 1391
1392
A. HASLERet at.
Table 1. 13C NMR data (75 MHz, CD,OD) 1
C
Flavonol nucleus 159.4 s 2 135.5 s 3 179.6 s 4 163.2 s 5 100.0 d 6 166.0 s 7 94.9 d 8 158.6 s 9 106.0 s 10 122.6 s 1’ 132.0 d 2 116.6 d 3’ 161.7 s 4 116.6 d 5’ 132.0 d 6 Rharnnose 102.6 d I” 82.7 d 2” 71.8 d 3” 13.5 d 4” 72.0 d 5” 17.7 q 6” Glucose 107.1 d 1I,, 75.4 d 21,1 71.9 d 3 I,?
4” 5”
71.0 d
78.0 d 62.4 t 6 (11 Coumaric acid 1”” 2”” 3111, 4”’ 5,r,, 6 ,I,! 7,.=2.2 Hz, J 6”“A,5”,A= 11.9 Hz, H-61;), 4.97 (1H, d, J = 7.0 Hz, ‘H-Y), 5.79 (lH, d, H-l”), 6.03 (lH, d, 5=16.OHz, H-Y), 6.f3 (IH, d, J =2.0Hz, H-6), 6.16 (lH, d, J=20Hz, H-S), 6.93 (IH, d, J = 8.6 Hz, H-S), 6.95 (2H, d, J = 8.8 Hz., H-6”” and H-8”“), 7.27 (3H, m, H-6’, H-S”’ and H-9”“), 7.31 (lH, d, J,,,& = 1.9 Hz, H-2’), 7.41 (iH, d, J=16.OI-k, H-3”“). For “CNMR (75SMHz, CD,OD) see Table 1.
1394
A. HASLERet al.
UV FAB-MS: mjz 919 [M+H]*, 303 [aglycone~~~+. I:$‘” nm: 256,26Ssh, 3OOsh.3 14,36Osh, N&Me 260,363; AICI, 276,297sh. 311sh, 435; AKLHCI 276.294sh. 313.398: NaOAc 2#0,314,342; NaoAc~H,Bcj, 261,316,368. tiv Lkurn after partial alkaline hydrolysis: 257, 264sh, 346; NaOMe 262, 396; AK& 273, 30% 324, 428; AR&-HCl 270, 298sh, 358, 394; NaOAc 256,396; NaOAc-HsBO, 260,317. ‘H NMR (300 MHz, CD&D) 6: 1.08 (3H, d. J -6.2 Hz, H-6”), 3.26357 (9H, m, sugar t* protons), 3.74 (IH, dd, Js,,,*,=9.5 H7, J 5r,.6., =6.2 Hz, H-5 ), 3.76 (IN, ABX, Jb.v.,a ,...==5.5 Hz, J, I.,>, n 6.,/,,,,=11.9 Hz, H&,..:9.8 Hz, H-3”), 3.96 @;;“‘),3.89 (IH, dd, J s.,,.,=3SHz, ,’ (1% ABX, J,..,.,,_,p..,, a=f1.9 Hz, H-6r). 4.08 (1H. ABX, J,...a,s.,, =6.6 Hz, _3s”‘n6,,.Ac Il.9 Hz, H-5;;‘), 4.34 (IX, dd, J,.,,,,.=3.5 Hz, H-2”), 4.40 (IH, d, J==7.8 Hz, H-l”‘), 4.52 (IH, ABX, J,...,,,,..=2.1 Hz, J6.’ A 6”,s= 11.9 Hz, H-6;). 5.03 (iH, d, .I=7.1 Hz,H-l”“‘),5.72(1H,~,H-l”),6.~(tH,d,J=16.0Hz,H2”“), 6.41 (1H, d, J=2.0Hz, H-6), 6.50 (1H, d, .l=2.OHz, H-8), 6.66 (ZH, d, J= 8.5 Hz. H-6”” and H-8”“), 6.90 (1 H. d, J = 8.4 Hz, H-5’), 7.17 (2H, d, 6x8.5 Hz, H-S”’ and H-s”“), 7.23 (1H, dd, J ,,.~,‘1.9Hz,J6..~.=8.4Hz,H-6’).7.33(1H,d,Jz,.6.=1.9Hz, H-2’), 7.40(1H, d, J= 16.0 Hz, H-3”“). For ‘Y?NMR (75.5 MHz, CD&D) see Table J. ~ckna~~edge~nts-
-Finauc~ai support by Zeller ACi Romanshorn, Switzerland is gratefully acknowledged, We also thank
Dr A. Wright (Department of Pharmacy, ETH-Zilch)
for the NMR measurements and R. Hiifliger (Depa~ment of Chemistry, ETH-Zurich) for FAB-MS measurements,
1. F~nfgeld, E. W. (ed.) (1988) R&n, G~~kgu b&&a, Recent Results in ~~rrnac~~og~ and in C&tic. Springer, Berlin.
2. Hasler, A. (1990) Thesis, E’I’H Zurich, No. 9353. Zurich, Switzerland. 3. Hasler, A., M&r, B. and Sticher, 0. (1990) J. C~~o~~ro~~. 508, 236. 4. Ha&r, A., Meier, B. and Sticher, 0. (1990) Schweiz. Apotheker Zeit. lzs, 341. 5. Mabry, T. J., Markb~, K. R. and Thomas, M. B. (1970) The Systematic ident~~cati~~ o~~lu~~~~ids. Springer, Berlin. 6. Markham, K. R. (1982) Techniques of ~~a~~un~~d ~dentz~cffrjon. Academic Press, London. 7. Bacon, J. D. and Mabry T, J. (1976) Rea. ~ti~ou?~. Quim, 7, 83. 8. AgrawaI, P. K. (~989) Carbon-13 NMR of ~~av~~~~d~. Elsener, Amsterdam.
