Ferulic acid esters of glucosylglucose from Allium macrostemon Bunge

Article abstract of DOI:10.1080/10286020.2016.1213722

Three new ferulic acid esters of glucosylglucose, 1-O-(E)-feruloyl-β-d-glucopyranosyl (1-2)-[β- d-glucopyranosyl (1-6)]-β-d-glucopyranose (allimacronoid A, 1), 1-O-(E)-feruloyl-{β-d-glucopyranosyl (1-4)-[β-d-glucopyranosyl (1-2)]}-[β- d-glucopyranosyl (1-6)]-β-d-glucopyranose (allimacronoid B, 2), and 1-O-(E)-feruloyl-{β-d-glucopyranosyl (1-6)-[β-d-glucopyranosyl (1-2)]}-[β- d-glucopyranosyl (1-6)]-β-d-glucopyranose (allimacronoid C, 3) were isolated together with tuberonoid A (4), from the leaves of Allium macrostemon Bunge. The chemical structures were elucidated based on the analyses of the spectroscopic and chemical data.

Full text of DOI:10.1080/10286020.2016.1213722

Journal of Asian Natural Products Research
ISSN: 1028-6020 (Print) 1477-2213 (Online) Journal homepage: http://www.tandfonline.com/loi/ganp20
Ferulic acid esters of glucosylglucose from Allium
macrostemon Bunge
Ayaka Usui, Yosuke Matsuo, Takashi Tanaka, Kazusato Ohshima, Shinji
Fukuda, Takara Mine, Ichiro Yakashiro & Kanji Ishimaru
To cite this article: Ayaka Usui, Yosuke Matsuo, Takashi Tanaka, Kazusato Ohshima,
Shinji Fukuda, Takara Mine, Ichiro Yakashiro & Kanji Ishimaru (2016): Ferulic acid esters of
glucosylglucose from Allium macrostemon Bunge, Journal of Asian Natural Products Research,
DOI: 10.1080/10286020.2016.1213722
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Date: 04 September 2016, At: 20:23

Journal of asian natural Products research, 2016
http://dx.doi.org/10.1080/10286020.2016.1213722
Ferulic acid esters of glucosylglucose from
Allium macrostemon Bunge
Ayaka Usuia, Yosuke Matsuob, Takashi Tanakab, Kazusato Ohshimaa, Shinji Fukudaa,
Takara Minec, Ichiro Yakashiroc and Kanji Ishimarua
afaculty of agriculture, saga university, saga 840-8502, Japan; bGraduate school of Biomedical sciences and
school of Pharmaceutical sciences, nagasaki university, nagasaki 852-8521, Japan; csaga Prefectural institute
of Public health and Pharmaceutical research, saga 849-0925, Japan
ABSTRACT
ARTICLE HISTORY
received 12 March 2016
accepted 12 July 2016
Three new ferulic acid esters of glucosylglucose, 1-O-(E)-feruloyl-β-d-
glucopyranosyl (1-2)-[β- d-glucopyranosyl (1-6)]-β-d-glucopyranose
(allimacronoid A, 1), 1-O-(E)-feruloyl-{β-d-glucopyranosyl (1-4)-[β-d-
glucopyranosyl (1-2)]}-[β- d-glucopyranosyl (1-6)]-β-d-glucopyranose
(allimacronoid B, 2), and 1-O-(E)-feruloyl-{β-d-glucopyranosyl
(1-6)-[β-d-glucopyranosyl (1-2)]}-[β- d-glucopyranosyl (1-6)]-β-d-
glucopyranose (allimacronoid C, 3) were isolated together with
tuberonoid A (4), from the leaves of Allium macrostemon Bunge. The
chemical structures were elucidated based on the analyses of the
spectroscopic and chemical data.
KEYWORDS
amaryllidaceae; Allium
macrostemon; ferulic acid;
glucosylglucose; ester
1. Introduction
Allium macrostemon Bunge (Amaryllidaceae), known as wild onion, is widely distributed in
East Asian countries. Some steroidal saponins have been isolated from the bulb [1], which
showed various biological activities [2–5] such as acute myocardial ischemia, hyperglycemia,
hyperlipidemia, and visceral obesity, etc. In Japan, the species is well-known edible weed
like other Allium species such as onion (A. cepa L.), garlic (A. sativum L.), and Welsh onion
(A. fistulosum L.), etc. Nakane et al. reported the isolation and HPLC analysis of the flavo-
nol glycoside constituents in the aerial part (leaf) of this plant [6]. In the present chemical
research on the phenolic compounds in the leaves of this species, three new ferulic acid
esters of glucosylglucose (1–3) were isolated, together with a known one tuberonoid A (4)
[7], and the chemical structures were elucidated.
2. Results and discussion
e known compound 4 was identified as tuberonoid A {1-O-(E)-feruloyl-β-d-
glucopyranosyl (1-2)-β-d-glucopyranose}, which was isolated from A. tuberosum, by com-
parison of the spectroscopic data with those of reported [7].
CONTACT Kanji ishimaru
kanji@cc.saga-u.ac.jp
© 2016 informa uK limited, trading as taylor & francis Group

2
A. USUI eT Al.
A new compound 1 gave a quasi-molecular ion peak at m/z 679.2100 [M−H]−, which
1
corresponded to the molecular formula C28H40O19. e H-NMR spectrum (Table 1) of
compound 1 showed ABX-type (δ 6.81, J = 8.2 Hz, 1H; δ 7.11 J = 2.0, 8.2 Hz, 1H and
δ 7.23, J = 2.0 Hz, 1H) aromatic proton signals together with trans-olefinic (δ 6.42 and 7.72,
J = 15.8 Hz, each 1H) and a methoxyl (δ 3.90, 3H) signals and three sugar anomeric (δ 5.69,
J = 7.8 Hz, δ 4.59, J = 7.8 Hz, and δ 4.33, J = 7.8 Hz) proton signals. In the 13C-NMR spectrum
of 1 (Table 2), 9 carbon signals of an aglycone (δ 111.9, 114.9, 116.5, 124.5, 127.5, 148.3,
149.4, 151.0, and 167.4), together with a methoxyl signal (δ 56.5), which were attributable to
ferulic acid [7], were observed, as well as other sugar signals (18 carbons), which indicated
the presence of 3 hexose moieties. e nuclear magnetic resonance (NMR) data of 1 were
very similar to those of 4, with the major difference of the existence of additional sugar
unit, showing 1 to be as a ferulic acid ester of triglycoside. By the method of Tanaka et al.
[8], the hexose components of 1 were identified as d-glucose. e positions of the glucoses
Table 1. 1h nMr spectral data (δ) of compounds 1–3 (cd3od).
No.
Compound 1
Compound 2
Compound 3
Ferulic acid
2
5
6
7
8
oMe
7.23 (1h, d, 2.0)
6.81 (1h, d, 8.2)
7.11 (1h, dd, 2.0, 8.2)
7.72 (1h, d, 15.8)
6.42 (1h, d, 15.8)
3.90 (3h, s)
7.22 (1h, d, 1.9)
6.81 (1h, d, 8.2)
7.11 (1h, dd, 1.9, 8.2)
7.72 (1h, d, 16.1)
6.42 (1h, d, 16.1)
3.90 (3h, s)
7.23 (1h, d, 1.9)
6.83(1h, d, 8.2)
7.14 (1h, dd, 1.9, 8.2)
7.71 (1h, d, 15.9)
6.41 (1h, d, 15.9)
3.91 (3h, s)
Glucose-1
1
2
3
4
5
6
5.69 (1h, d, 7.8)
5.71 (1h, d, 7.8)
5.71 (1h, d, 8.1)
3.61–3.69 (1h, m)
3.61–3.69 (1h, m)
3.49 (1h, t, 9.5)
3.54–3.60 (1h, m)
3.78 (1h, dd, 11.5, 5.1)
4.17 (1h, dd, 11.5, 1.7)
3.62–3.68 (1h, m)
3.62–3.68 (1h, m)
3.47–3.54 (1h, m)
3.55–3.62 (1h, m)
3.74–3.79 (1h, m)
4.17 (1h, dd, 11.5, 1.7)
3.79–3.81 (1h, m)
3.64–3.69 (1h, m)
3.54 (1h, t, 8.8)
3.56–3.62 (1h, m)
3.77–3.82 (1h, m)
4.16 (1h, dd, 11.4, 1.6)
Glucose-2
1′
2′
3′
4′
5′
6′
4.59 (1h, d, 7.8)
3.18 (1h, dd, 7.8, 8.5)
3.36 (1h, t, 8.5)
3.30–3.34 (1h, m)
3.22–3.29 (1h, m)
3.54–3.60 (1h, m)
3.61–3.67 (1h, m)
4.61 (1h, d, 7.8)
4.61 (1h, d, 7.8)
3.22–3.26 (1h, m)
3.51–3.54 (1h, m)
3.51–3.55 (1h, m)
3.32–3.38 (1h, m)
3.69–3.75 (2h, m)
3.16–3.20 (1h, m)
3.31–3.38 (1h, m)
3.30–3.34 (1h, m)
3.37–3.42 (1h, m)
3.68–3.73 (1h, m)
4.00 (1h, dd, 11.6, 2.0)
Glucose-3
1″
2″
3″
4″
5″
6″
4.33 (1h, d, 7.8)
3.20 (1h, t, 7.8)
3.22–3.29 (1h, m)
3.22–3.29 (1h, m)
3.22–3.29 (1h, m)
3.61–3.69 (1h, m)
3.84 (1h, dd, 11.7, 1.5)
4.31 (1h, d, 8.8)
3.20 (1h, t, 8.8)
3.25–3.30 (1h, m)
3.25–3.30 (1h, m)
3.30–3.35 (1h, m)
3.62–3.68 (1h, m)
3.84 (1h, br.d, 10.7)
4.34 (1h, d, 7.8)
3.19–3.26 (1h, m)
3.31–3.38 (1h, m)
3.22–3.30 (1h, m)
3.21–3.28 (1h, m)
3.60–3.65 (1h, m)
3.81–3.86 (1h, m)
Glucose-4
1‴
2‴
3‴
4‴
5‴
6‴
4.35 (1h, d, 8.1)
3.17 (1h, t, 8.1)
3.25–3.30 (1h, m)
3.25–3.30 (1h, m)
3.25–3.30 (1h, m)
3.57–3.68 (2h, m)
4.42 (1h, d, 7.8)
3.16 (1h, t, 7.8)
3.31–3.38 (1h, m)
3.22–3.30 (1h, m)
3.21–3.28 (1h, m)
3.64–3.68 (1h, m)
3.75–3.78 (1h, m)

JOUrNAl OF ASIAN NATUrAl PrOdUCTS reSeArCh
3
Table 2. 13c nMr spectral data (δ) of compounds 1–3 (cd3od).
No.
Compound 1
Compound 2
Compound 3
Ferulic acid
1
2
3
4
5
6
7
8
127.5
111.9
149.4
151.0
116.5
124.5
148.3
114.9
167.4
56.5
127.5
111.9
149.4
151.0
116.6
124.5
148.4
114.9
167.3
56.5
127.5
112.1
149.5
151.1
116.6
124.5
148.3
115.0
167.4
56.6
9
oMe
Glucose-1
1
2
3
4
5
6
94.4
82.7
77.5*
70.6
78.0*
69.5
94.3
83.2
77.4
70.6
77.6
69.4
94.5
81.5
77.6
70.6
77.4
69.5
Glucose-2
1′
2′
3′
4′
5′
6′
105.6
75.9
77.6*
71.0
78.0*
62.2
105.6
75.7
76.0
80.3
76.5
61.5
104.8
75.7
77.7*
71.4
77.3
69.5
Glucose-3
1″
2″
3″
4″
5″
6″
104.5
75.1
77.7*
71.5
78.0*
62.7
104.5*
75.1
77.8**
71.5
77.9**
62.7
104.6
75.0
77.8*
71.5
77.8*
62.6
Glucose-4
1‴
2‴
3‴
4‴
5‴
6‴
104.6*
74.9
77.9**
71.3
78.0**
62.4
104.5
75.0
77.9*
71.5
78.0*
62.7
*, ** assignments bearing the same superscript may be interchangeable in the same column.
were confirmed by NMR (COSY, HSQC, and HMBC) spectral data of 1. In particular, the
HMBC spectrum showed the correlations originated from the carbon linkages between
glucose C-1 – ferulic acid C-9, glucose C-1′ – glucose C-2, and glucose C-1″ – glucose C-6
(Figure 1). e large J values of three anomeric proton signals in the 1H-NMR spectrum of
1 (Table 1) also confirmed the β configurations. From the data mentioned, 1 was concluded
to be as 1-O-(E)-feruloyl-β-d-glucopyranosyl (1–2)-[β- d-glucopyranosyl (1–6)]-β-d-glu-
copyranose and named as allimacronoid A (1).
Compound 2 showed a quasi-molecular ion peak at m/z 841.2620 [M−H]− (corresponded
1
to the molecular formula C34H50O24). e H- and 13C-NMR spectral data of 2 (Tables 1
and 2) whose assignment was also certified by COSY, HSQC, and HMBC spectra, were
similar to those of 1 with the difference of the signals coming from an additional hexose
moiety, suggesting 2 to be as a ferulic acid ester of tetraglycoside. e sugar components of

4
A. USUI eT Al.
6
2
5
7
HOH2C
O
1''
O
9
OH
8
H
O
C
HO
HO
CH2
O
OH
1
O
OCH3
HO
H
HO
O
1'
O
HOH2C
H
OH
HO
HO
1
HOH2C
O
1''
O
OH
H
O
C
O
HO
HO
CH2
O
OH
1
OCH3
HO
H
HO
O
1'
O
HOH2C
H
OH
O
1'''
HOH2C
O
HO
H
OH
HO
HO
2
HOH2C
O
1''
O
OH
H
O
C
O
HO
HO
CH2
O
OH
1
OCH3
HO
H
HO
O
1'
O
O
H
H2C
1'''
O
HOH2C
HO
H
OH
OH
HO
HO
HO
3
Figure 1. chemical structures and the selected hMBc correlations (h→c) of 1–3.
2 were identified as d-glucose by HPLC analysis [8]. e HMBC spectrum of 2 also showed
the correlations arising from the carbon linkages between glucose C-1 – ferulic acid C-9,
glucose C-1′ – glucose C-2, glucose C-1″ – glucose C-6 and glucose C-1‴ – glucose C-4′

JOUrNAl OF ASIAN NATUrAl PrOdUCTS reSeArCh
5
(Figure 1). e J values of the four anomeric proton signals in the 1H-NMR spectrum of 2
(Table 1) indicated β configurations of the anomeric carbons. From the data described above,
2 was concluded to be 1-O-(E)-feruloyl-{β-d-glucopyranosyl (1-4)-[β-d-glucopyranosyl
(1-2)]}-[β- d-glucopyranosyl (1-6)]-β-d-glucopyranose and named as allimacronoid B (2).
Compound 3 showed a quasi-molecular ion peak at m/z 841.2624 [M−H]− (corresponded
1
to the molecular formula C34H50O24). e H- and 13C-NMR spectral data of 3 (Tables 1
and 2, assignment was certified by COSY, HSQC, and HMBC spectra) were almost iden-
tical with those of 2, suggesting 3 to be as a ferulic acid ester of tetraglycoside. e sugar
components of 3 were identified as d-glucose [8]. e HMBC spectrum of 3 certified the
carbon linkages between glucose C-1 – ferulic acid C-9, glucose C-1′ – glucose C-2, glucose
C-1″ – glucose C-6, and glucose C-1‴ – glucose C-6′ (Figure 1). e large J values of the four
anomeric proton signals in the 1H-NMR spectrum (Table 1) indicated β configurations of
the anomeric carbons, and 3 was elucidated to be as 1-O-(E)-feruloyl-{β-d-glucopyranosyl
(1-6)-[β-d-glucopyranosyl (1-2)]}-[β- d-glucopyranosyl (1-6)]-β-d-glucopyranose and
named as allimacronoid C (3).
Although ferulic acid is commonly distributed in Allium species [9], the ester derivatives
with oligo-glucose are rarely found. Han et al. reported tuberonoid A (4) from A. tuberosum
[7] and some flavonol sophorosides (glucosyl C1 – C2 glucose) were isolated from the leaf
epidermis of A. cepa [10]. It is very noteworthy that A. macrostemon Bunge contains various
types of ferulic acid esters with oligo-glucose.
3. Experimental
3.1. General experimental procedures
Optical rotation was measured with JASCO DIP-1000 Digital Polarimeter (JASCO Ltd.,
Tokyo, Japan). Ultra–violet spectra were measured in MeOH using JASCO V-530 UV/
VIS spectrophotometer (JASCO Ltd., Tokyo, Japan). Infrared spectra were measured using
JASCO FT/IR-400 Spectrophotometer (JASCO Ltd., Tokyo, Japan). NMR spectra were
1
recorded in CD3OD using a JEOL JNM-A500 spectrometer (500 MHz for H-NMR and
125 MHz for 13C-NMR) (JEOL Ltd., Tokyo, Japan). Negative-ion HRESI-TOF-MS was
recorded on an Agilent Technologies 6540 Accurate-Mass Q-TOF LC/MS spectrometer
(Agilent Technologies Japan Ltd., Tokyo, Japan). For column chromatography, DIAION
HP20SS (Mitsubishi Chemical Corporation), Sephadex LH20 (Pharmacia Corporation) and
Cosmosil 140C18-OPN (Nacalai Tesque Inc.) were used. Preparative HPLC was performed
on a JASCO preparative HPLC system (Pump: PU-2086 Plus, Detector: UV-2075 Plus,
detected at 254 nm) equipped with a ZORBAX SB-C18 (9.4 mm i.d. × 250 mm, Agilent)
column, with 30% MeOH (3 ml/min) as the eluent.
3.2. Plant material
e leaves of Allium macrostemon Bunge, grown in the campus of Saga University, Japan,
were collected in February 2015. e plant material was identified by one of the authors
(K. Ohshima, professor of the laboratory of Plant Virology, Saga University). A voucher
sample is deposited in the laboratory of Analysis of Plant Metabolism at the Faculty of
Agriculture, Saga University.

6
A. USUI eT Al.
3.3. Extraction and isolation
e fresh leaves (600 g) of A. macrostemon Bunge were extracted with 60% aqueous EtOH
(2.5 L) for 2 days. e solvent was concentrated in vacuo and subjected to a column
of Cosmosil 140C18-OPN, which was eluted with H2O containing increasing amount of
MeOH to afford three fractions of Fr. 1 (15 g), Fr. 2 (8 g), and Fr. 3 (8 g). Fr. 1 was puri-
fied with Sephadex LH20 (60% aqueous EtOH) and DIAION HP20SS (stepwise elution
with H2O and MeOH) column chromatographies to afford two fractions (Fr. 1-1 and Fr.
1-2). Fr. 1-1 (1 g) was applied to Cosmosil 140C18-OPN (stepwise elution with H2O and
MeOH) and DIAION HP20SS (stepwise elution with H2O and MeOH) column chroma-
tographies to afford two fractions (Fr. 1-1-1 and Fr.1-1-2). Fr. 1-1-1 (0.1 g) was purified
by preparative HPLC separation to give 3 (6 mg, Rt = 6.5 min). Fr. 1-1-2 (0.3 g) was
purified by preparative HPLC separation to give 1 (16 mg, Rt = 9.5 min) and 2 (10 mg,
Rt = 7.3 min). Fr. 1-2 (3 g) was applied to Cosmosil 140C18-OPN (stepwise elution with
H2O and MeOH) column chromatography, followed by preparative HPLC separation to
give 4 (36 mg, Rt = 13.5 min).
3.3.1. Allimacronoid A (1)
Off-white amorphous powder; [ꢀ]2D1 −36.0 (c 0.13, MeOH). UV λ MeOH nm (log ε): 329
(4.25). IR νmax cm−1: 3379, 2924, 1712, 1631, 1596, 1516, 1276, 1165,m1a0x89, 897, 579. 1H-NMR
spectral data, see Table 1. 13C-NMR spectral data, see Table 2. HRESI-TOF-MS (negative-ion
mode) m/z: 679.2100 [M−H]− (calcd for C28H39O19, 679.2085).
3.3.2. Allimacronoid B (2)
Off-white amorphous powder, [ꢀ]1D8 −13.9 (c 0.09, MeOH). UV λmax MeOH nm (log ε): 330
(4.00). IR νmax cm−1: 3439, 2923, 1712, 1630, 1595, 1516, 1430, 1373, 1275, 1164, 1092, 635.
1H-NMR spectral data, see Table 1. 13C-NMR spectral data, see Table 2. HRESI-TOF-MS
(negative-ion mode) m/z: 841.2620 [M−H]− (calcd for C34H49O24, 841.2613).
3.3.3. Allimacronoid C (3)
Off-white amorphous powder, [ꢀ]1D8 −21.7 (c 0.13, MeOH). UV λmax MeOH nm (log ε): 329
(4.14). IR νmax cm−1: 3415, 2921, 1711, 1630, 1594, 1515, 1271, 1065, 1029. 1H-NMR spectral
data, see Table 1. 13C-NMR spectral data, see Table 2. HRESI-TOF-MS (negative-ion mode)
m/z: 841.2624 [M−H]− (calcd for C34H49O24, 841.2613).
3.4. HPLC-QTOF-MS analysis of 1–3
Negative-ion HRESI-TOF-MS of 1–3 was obtained in the HPLC-QTOF-MS analysis
as following conditions. HPLC system (Agilent 1100 series); column：Agilent Eclipse
Plus C18 (2.1 mm i.d. × 100 mm, 1.8 μm), mobile phase: 0.1% formic acid with 2.5 mM
AcONH4-CH3CN [90:10 (0 min)→10:90 (20 min)], flow rate: 0.2 ml/min, column temper-
ature: 40 °C, detection: 280 nm (UV), retention times (min): 3 (2.0), 2 (2.4) and 1 (3.0).
TOFMS system (Agilent G1969A); ionization: ESI (negative), drying gas: N2, 350 °C,
10 L/min, nebulizer gas: N2, 50 psig, capillary: 4000 V, fragmentor: 150 V, mass range:
50–1700 m/z.

JOUrNAl OF ASIAN NATUrAl PrOdUCTS reSeArCh
7
3.5. Identification of sugar moieties of 1–3
Identification of the sugar moieties of 1–3 was done by the following analytical method of
Tanaka et al. [8]. A solution of 1–3 (0.5 mg) in 0.5 M HCl (0.1 ml) was heated at 95 °C in
a screw-capped vial for 2 h. e mixture was neutralized by addition of Amberlite IRA400
(OH− form) and filtered. e filtrate was dried in vacuo, dissolved in 0.1 ml of pyridine
containing L-cysteine methyl ester (5 mg/ml) and reacted at 60 °C for 1 h. To the mixture,
a solution (0.1 ml) of o-toryl isothiocyanate in pyridine (5 mg/ml) was added and it was
heated at 60 °C for 1 h. e final mixture was directly analyzed by HPLC [Cosmosil 5C18
AR II (250 × 4.6 mm i.d., Nacalai Tesque Inc.); 25% CH3CN in 50 mM H3PO4; flow rate,
0.8 ml/min; column temperature, 35 °C; detection, 250 nm]. e tRs of the peak at 15.84 min
for 1, 15.83 for 2, and 15.89 min for 3 coincided with that of d-glucose (15.82 min).
Disclosure statement
No potential conflict of interest was reported by the authors.
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