Synthesis of stigmasteryl (β1→4)-oligoglucosides

Article abstract of DOI:10.1080/07328303.2015.1136321

Stigmasteryl (β1→4)-oligoglucosides were prepared with cellobiose, cellotriose, and cellotetraose as glycan chains. For the preparation of the peracetylated oligoglucosyl donors anomeric acetate was deprotected and the respective hemiacetals were converted into trichloroacetimidates. Glycosylation with stigmasterol yielded both α-and β-anomers because during the treatment with Lewis acid the 2-OAc is cleaved to some extent; thus, with the emerging hydroxyl group neighboring group participation does not take place. Due to their different number of hydroxyl groups (0 vs. 1) separation of the two products proved to be facile. Saponification led to the desired stigmasteryl glucosides.

Full text of DOI:10.1080/07328303.2015.1136321

Journal of Carbohydrate Chemistry
ISSN: 0732-8303 (Print) 1532-2327 (Online) Journal homepage: http://www.tandfonline.com/loi/lcar20
Synthesis of stigmasteryl (β1→4)-oligoglucosides
Katharina Kettelhoit & Daniel B. Werz
To cite this article: Katharina Kettelhoit & Daniel B. Werz (2016) Synthesis of
stigmasteryl (β1→4)-oligoglucosides, Journal of Carbohydrate Chemistry, 35:1, 24-39, DOI:
10.1080/07328303.2015.1136321
To link to this article: http://dx.doi.org/10.1080/07328303.2015.1136321
Published online: 24 Mar 2016.
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Date: 29 March 2016, At: 12:43

JOURNAL OF CARBOHYDRATE CHEMISTRY
, VOL. , NO. , –
http://dx.doi.org/./..
Synthesis of stigmasteryl (β→)-oligoglucosides
Katharina Kettelhoit and Daniel B. Werz
Institut für Organische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
ABSTRACT
ARTICLE HISTORY
Received  November 
Accepted  December 
Stigmasteryl (β1→4)-oligoglucosides were prepared with cel-
lobiose, cellotriose, and cellotetraose as glycan chains. For the
preparation of the peracetylated oligoglucosyl donors anomeric
acetate was deprotected and the respective hemiacetals were
converted into trichloroacetimidates. Glycosylation with stigmas-
terol yielded both α- and β-anomers because during the treat-
ment with Lewis acid the 2-OAc is cleaved to some extent;
thus, with the emerging hydroxyl group neighboring group par-
ticipation does not take place. Due to their different number
of hydroxyl groups (0 vs. 1) separation of the two products
proved to be facile. Saponification led to the desired stigmasteryl
glucosides.
KEYWORDS
Glycosylation; neighboring
group participation;
peracetylated glycans;
saponins; stigmasterol
Introduction
Saponins represent a class of naturally occurring high molecular weight glycosides
with triterpenes or steroids as aglycone. They are found in numerous plants like
soybeans, chick peas, oats, and lentils where they are believed to play a significant
physiological role (Fig. 1). Many saponin-containing plants are applied in natural
medicine due to their broad therapeutic effects.[1] Saponins are considered to make
up the major active compounds of ginseng. Due to their amphiphilic nature con-
sisting of the polar glycan unit and the apolar steroid scaffold, special physicochem-
ical and biological properties arise. Several of these compounds are known to have
hemolytic properties or are even toxic to cold-blooded animals.[2] But also in terms
of self-assembly interesting features are expected because of the interplay of polar
and apolar parts in the molecules.
A special class of very simple saponins with stigmasterol as steroid scaffold
and 1,4-linked oligoglucoses of different chain length was observed in rice (Oryza
sativa). Both anomeric configurations (α and β), with β being the major isomer,
were found at the stereocenter at the reducing end linking the glycan to the agly-
con.[5] Because of the extreme importance of rice for the nutrition of mankind, it is
worth to further investigate the potential bioactivity of these compounds. Since only
miniscule amounts of the respective stigmasteryl oligoglucosides are accessible by
CONTACT Daniel B. Werz
d.werz@tu-braunschweig.de
Braunschweig,  Braunschweig, Germany.
Institut für Organische Chemie, Technische Universität
©  Taylor & Francis Group, LLC

JOURNAL OF CARBOHYDRATE CHEMISTRY
25
Figure . Examples of literature-known saponins and our target compounds.[,]
isolation from the plant chemical synthesis is the way to go.[3,6] Herein, we report a
general approach for the synthesis of stigmasteryl (β1→4)-oligoglucosides leading
to both, α- and β-linkages at the reducing end of the glycan chain.
Results and discussion
Our approach to access both, α- and β-linked stigmasteryl derivatives starts
with commercially available cellobiose, cellotriose, and cellotetraose. The naked
oligosaccharides were converted quantitatively to the peracetylated congeners by
using acetic anhydride in pyridine. Anomeric deprotection was achieved by using
hydrazine acetate in tetrahydrofuran (THF) at room temperature.[7] The respec-
tive hemiacetals were converted into the oligoglucosyl trichloroacetimidates in good
yields (Sch. 1).[8]
Commonly, the acetate group in position 2 of glucose secures β-stereochemistry
of the emerging glycosidic bond because of neighboring group participation. How-
ever, very recently it was reported that an acetate group in this position is rather
labile and might be cleaved when the glycosyl donor gets activated. Therefore, many
groups use other protecting groups than acetate in this position to ensure the desired
1,2-trans-linkage.[9] However, we intended the fact that the acetate might be cleaved
can be turned into an advantage since the emerging hydroxyl group in position 2
might lead to α-stereochemistry. Furthermore, we assumed that the hydroxyl group
of the stigmasterol reveals a much higher nucleophilicity leading to a faster reaction
of the glycosyl donor rather than a reaction of the glycosyl donor with the 2-hydroxyl
of the oligoglycan chain.

26
K. KETTELHOIT AND D. B. WERZ
Scheme . Preparation of oligoglucosyl trichloroacetimidates 9–11.
Indeed, glycosylation of 9–11 with stigmasterol (12) utilizing catalytic amount
of trimethylsilyl trifluoromethanesulfonate (TMSOTf) as promotor afforded the
expected β-glycosides 13–15 together with respective α-linked congeners 16–18,
both in moderate yield (Sch. 2).
Since the α-products were deacetylated in position 2 during the course of the
reaction, the products revealing different polarity were easily separable by column
chromatography. As we expected deacetylation had occurred to some extent in 2-
position of the glucose unit adjacent to the aglycone. Thus, the α-glucoside was
formed as result of the non-participating hydroxyl group. A mechanism for this
deacetylation was postulated by Pakulski for similar substrates.[10] Upon activation
with the promotor, acyloxonium ion 19 is formed, followed by orthoester forma-
tion with the hydroxyl as nucleophile. Rearrangement of the orthoester then releases
deacetylated oxocarbenium ion 21 and ester 22 (Sch. 3). In our protocol, the nucle-
ophile stigmasterol (12) was utilized in excess, i.e., 21 was able to undergo the glyco-
sylation reaction affording preferentially the α-product. The acetylated nucleophile
22 with R = stigmasteryl was once isolated in 54% yield to support the postulated
deacetylation mechanism.
Finally, all conjugates were subjected to saponification with NaOMe providing six
different saponins in good to excellent yields (Sch. 4).
Conclusion
In summary, we have developed an efficient method for the preparation of stig-
masterol saponins containing β(1→4)-linked oligo-d-glucans of different length.
The glycosylation using peracetylated glucosyl trichloroacetimidates was designed

JOURNAL OF CARBOHYDRATE CHEMISTRY
27
Scheme . Glycosylation of stigmasterol (12) with oligoglucosyl trichloroacetimidates 9–11.
in such a way that both, the α- and β-anomer, were obtained. During the course
of the reaction partial deacetylation in position 2 adjacent to the trichloroacetim-
idate took place resulting in a free hydroxyl group. This non-participating group
accounts for the α-anomer. Since the different anomers possess a different number
of hydroxyl groups (0 vs. 1), a separation by column chromatography was facile.
Saponification furnished the respective saponins.
Experimental
Solvents were dried by standard procedures and distilled before use. All reactions
were carried out in oven-dried glassware, septum-capped under atmospheric pres-
sure of argon. Commercially available compounds were used without further purifi-
cation unless otherwise stated. Proton (1H) and carbon (13C) NMR spectra were
recorded on a 300, 400, or 600 MHz instrument using the residual signals from
Scheme . Deacetylation in position  due to putative orthoester formation.

28
K. KETTELHOIT AND D. B. WERZ
Scheme . Saponification with NaOMe in MeOH to afford the target compounds 23–28.
tetramethylsilane (TMS) δ = 0.00 ppm as internal references for 1H and 13C chem-
ical shifts, respectively. No integration was performed in case of α/β mixtures.
Electrospray Ionization High-Resolution Mass Spectrometry (ESI-HRMS) was car-
ried out on a Fourier Transform Ion Cyclotron Resonance (FTICR) instrument. IR
spectra were measured on an Attenuated Total Reflection (ATR) spectrometer. d-
Cellobiose octaacetate (3) was purchased from Alfa Aesar.
General procedure for the acetylation
To a solution of the respective saccharide in dry pyridine and acetic anhydride
(3:2, 0.01 m) was added one crystal of 4-Dimethylaminopyridine (DMAP). After
stirring for 12 h at ambient temperature, the reaction was stopped by the addi-
tion of sat. aq. NaHCO3-solution. The aqueous phase was extracted with EtOAc
(2×), and the combined organic layers were dried over Na2SO4, filtered, and con-
centrated in vacuo. The residue was purified by column chromatography (SiO2, n-
pentane/EtOAc).
General procedure for the anomeric deprotection
To a solution of the peracetylated sugar (1.00 equiv) in dry THF (0.04 m) was
added hydrazine acetate (1.20 equiv). After stirring for 5–9 h at ambient temper-
ature, EtOAc and H2O were added. The organic layer was washed with brine and

JOURNAL OF CARBOHYDRATE CHEMISTRY
29
sat. aq. NaHCO3-solution, dried over Na2SO4, filtered, and concentrated in vacuo.
The residue was purified by column chromatography (SiO2, n-pentane/EtOAc).
General procedure for the preparation of the trichloroacetimidate
A solution of the reducing sugar (1.00 equiv) in dry CH2Cl2 (0.08 m) was cooled to
0°C, and trichloroacetonitrile (20.0 equiv) and 1,8-Diazabicycloundec-7-ene (DBU)
(15.0 mol%) were added dropwise. The reaction mixture was stirred at 0 °C for 1.5 h,
and concentrated in vacuo at 30 °C. The residue was filtered through a plug of silica
(n-pentane/EtOAc, 1% NEt3) and directly used for the next step.
General procedure for the glycosylation
The respective trichloroacetimidate (1.00 equiv) and stigmasterol (2.00 equiv) were
azeotroped with toluene (3×) and dried in high vacuum for 1 h. Dry CH2Cl2 (0.1
m) was added and the solution was cooled to 0 °C. TMSOTf (15.0 mol%) was added
dropwise and the reaction mixture was stirred for 2 h at 0 °C. The reaction was
stopped by the addition of pyridine, the solvents were removed in vacuo, and the
residue was purified by column chromatography (SiO2, n-pentane/EtOAc).
General procedure for the saponification
To a solution of the protected glycosteroid in CH3OH and CH2Cl2 (3:1, 0.01 m)
was added NaOMe (5.4 m in methanol) until pH > 12. The solution was stirred at
ambient temperature for 20 h. The solution was neutralized with Amberlite®, diluted
with dimethyl sulfoxide (DMSO), filtered, and the solvents were removed in vacuo.
Dialysis and lyophilization afforded the desired products as white powders.
D-Cellotriose undecaacetate (4)
Acetylation of cellotriose (1) (200 mg, 0.396 mmol, 1.00 equiv) was performed
according to the general procedure in pyridine (24 mL) and acetic anhydride
(16 mL). Purification by column chromatography (SiO2, n-pentane/EtOAc 1:1.5)
afforded the peracetylated product 3 (375 mg, 0.388 mmol, 98%) as a pale yellow
solid as a mixture of anomers. The spectral data were in accordance with those
reported in the literature.[11]
D-Cellotetraose tetradecaacetate (5)
Acetylation of cellotetraose (2) (200 mg, 0.300 mmol, 1.00 equiv) was performed
according to the general procedure in pyridine (18 mL) and acetic anhydride (12
mL). Purification by column chromatography (SiO2, n-pentane/EtOAc 1:1.5 → 1:3)
afforded the peracetylated product 5 (369 mg, 0.294 mmol, 98%) as a pale yellow

30
K. KETTELHOIT AND D. B. WERZ
solid as a mixture of anomers. The spectral data were in accordance with those
reported in the literature.[11]
2,3,4,6-Tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-D-
glucopyranoside (6)
Anomeric deprotection of d-cellobiose octaacetate (3) (2.00 g, 2.95 mmol, 1.00
equiv) was performed according to the general procedure with hydrazine acetate
(326 mg, 3.54 mmol, 1.20 equiv) in THF (60 mL) for 5 h. Purification by
column chromatography (SiO2, n-pentane/EtOAc 1:1.5 → 1:3) afforded the
desired product 6 (1.37 g, 2.15 mmol, 73%) as a white solid as a mixture
of anomers. The spectral data were in accordance with those reported in the
literature.[12]
2,3,4,6-Tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-
glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-D-glucopyranoside (7)
Anomeric deprotection of d-cellotriose undecaacetate (4) (375 mg, 0.388 mmol,
1.00 equiv) was performed according to the general procedure with hydrazine
acetate (42.8 mg, 0.465 mmol, 1.20 equiv) in THF (8.0 mL) for 6 h. Purification by
column chromatography (SiO2, n-pentane/EtOAc 1:1.5 → 1:3) afforded the desired
product 7 (251 mg, 0.271 mmol, 70%) as a white solid as a mixture of anomers. TLC:
Rf = 0.2 (SiO2, n-hexane/EtOAc 1:1.5). 1H NMR (300 MHz, CDCl3): δ (ppm) = 1.98
(s), 1.99 (s), 2.00 (s), 2.00 (s), 2.01 (s), 2.02 (s), 2.04 (s), 2.07 (s), 2.09 (s), 2.13 (s), 2.14
(s), 2.14 (s), 3.19–3.28 (m), 3.54–3.69 (m), 3.69–3.84 (m), 3.96–4.23 (m), 4.30–4.43
(m), 4.42–4.58 (m), 4.71 (t, J = 7.9 Hz), 4.74–4.96 (m), 5.00–5.17 (m), 5.21 (t, J =
9.3 Hz), 5.37 (t, J = 3.6 Hz), 5.43–5.56 (m). 13C NMR (75 MHz, CDCl3): δ (ppm) =
20.5, 20.5, 20.6, 20.6, 20.7, 20.7, 20.8, 20.9, 20.9, 61.5, 61.6, 62.1, 67.7, 68.3, 68.2, 71.3,
71.6, 71.7, 71.7, 71.8, 72.1, 72.7, 72.7, 72.9, 73.0, 73.5, 76.1, 76.6, 77.2, 90.0, 100.4,
100.5, 100.7, 169.1, 169.2, 169.3, 169.6, 169.7, 169.8, 170.2, 170.2, 170.2, 170.3, 170.4,
170.5, 170.9. IR (ATR): v˜ (cm−1) = 3,479, 2,959, 1,738, 1,367, 1,212, 1,032, 903,
599. HRMS (ESI): m/z calcd. for C38H52O26Na+ [M+Na]+ 947.2639; found 947.
2636.
2,3,4,6-Tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-
glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-
O-acetyl-D-glucopyranoside (8)
Anomeric deprotection of d-cellotetraose tetradecaacetate (5) (346 mg, 0.275 mmol,
1.00 equiv) was performed according to the general procedure with hydrazine
acetate (30.5 mg, 0.331 mmol, 1.20 equiv) in THF (7.0 mL) for 9 h. Purification by
column chromatography (SiO2, n-pentane/EtOAc 1:1.5 → 1:3) afforded the desired
product 8 (239 mg, 0.197 mmol, 72%) as a white solid as a mixture of anomers.

JOURNAL OF CARBOHYDRATE CHEMISTRY
31
TLC: Rf = 0.2 (SiO2, n-hexane/EtOAc 1:3). 1H NMR (600 MHz, CDCl3): δ (ppm)
= 1.94–1.98 (m), 1.98 (s), 1.98–2.00 (m), 2.01 (s), 2.02 (s), 2.02 (s), 2.04 (s), 2.06 (s),
2.05–2.09 (m), 2.09 (s), 2.13 (s), 2.14 (s), 2.15 (s), 3.53–3.60 (m), 3.61–3.67 (m),
3.69–3.80 (m), 3.85 (dd, J = 6.7, 1.1 Hz), 4.03 (dd, J = 12.9, 2.1 Hz), 4.06–
4.13 (m), 4.14–4.20 (m), 4.36 (dd, J = 12.5, 4.3 Hz), 4.38–4.56 (m), 4.68–4.74
(m), 4.76–4.79 (m), 4.79–4.88 (m), 4.90 (ddd, J = 9.1, 7.9, 1.1 Hz), 5.03–5.09
(m), 5.09–5.16 (m), 5.17–5.24 (m), 5.34–5.40 (m), 5.49 (t, J = 9.7 Hz). 13C NMR
(151 MHz, CDCl3): δ (ppm) = 19.0, 20.4, 20.5, 20.5, 20.6, 20.6, 20.7, 20.7, 20.8,
20.8, 20.9, 20.9, 21.0, 27.6, 61.4, 61.3, 61.8, 62.1, 67.7, 68.2, 69.1, 70.6, 71.2, 71.5,
71.6, 71.7, 71.8, 71.9, 72.0, 72.5, 72.6, 72.6, 72.7, 72.7, 72.8, 73.0, 73.4, 76.0, 76.0,
76.1, 76.1, 76.5, 90.0, 95.3, 100.3, 100.5, 100.5, 100.8, 169.1, 169.2, 169.2, 169.3,
169.3, 169.6, 169.7, 169.8, 170.1, 170.2, 170.2, 170.2, 170.4, 170.4, 170.5, 170.9,
171.3. IR (ATR): v˜ (cm−1) = 3,472, 2,961, 1,738, 1,367, 1,212, 1,032, 902, 600.
HRMS (ESI): m/z calcd. for C50H68O34Na+ [M+Na]+ 1235.3484; found 1235.
3490.
2,3,4,6-Tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-D-
glucopyranosyl trichloroacetimidate (9)
Trichloroacetimidate 9 was synthesized according to the general procedure using
compound 6 (1.31 g, 2.06 mmol, 1.00 equiv), trichloroacetonitrile (5.94 g, 4.13 mL,
41.1 mmol, 20.0 equiv), and DBU (47.0 mg, 46.2 µL, 0.309 mmol, 15.0 mol%) in
CH2Cl2 (25 mL). Filtration through silica (SiO2, n-pentane/EtOAc 1:1.5, 1.0% NEt3)
afforded the desired product 9 (1.43 g, 1.83 mmol, 89%) as a yellow foam.
2,3,4,6-Tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-
glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-D-glucopyranosyl trichloroacetimidate
(10)
Trichloroacetimidate 10 was synthesized according to the general procedure using
compound 7 (245 mg, 0.265 mmol, 1.00 equiv), trichloroacetonitrile (765 mg,
531 µL, 5.30 mmol, 20.0 equiv), and DBU (6.04 mg, 5.94 µL, 0.0397 mmol, 15.0
mol%) in CH2Cl2 (3.3 mL). Filtration through silica (n-pentane/EtOAc 1:1.5, 1.0%
NEt3) afforded the desired product 10 (210 mg, 1.83 mmol, 74%) as a yellow
foam.
2,3,4,6-Tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-
glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-
acetyl-D-glucopyranosyl trichloroacetimidate (11)
Trichloroacetimidate 11 was synthesized according to the general procedure using
compound 8 (237 mg, 0.196 mmol, 1.00 equiv), trichloroacetonitrile (565 mg,

32
K. KETTELHOIT AND D. B. WERZ
392 µL, 3.91 mmol, 20.0 equiv), and DBU (4.48 mg, 4.40 µL, 0.0294 mmol, 15.0
mol%) in CH2Cl2 (2.5 mL). Filtration through silica (n-pentane/EtOAc 1:1.5 → 1:4,
1.0% NEt3) afforded the desired product 11 (222 mg, 1.83 mmol, 83%) as a beige
foam.
Stigmasteryl 2,3,4,6-Tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-
acetyl-D-glucopyranosides 13 and 16
Glycosylation was performed according to the general procedure using compound 9
(466 mg, 0.596 mmol, 1.00 equiv), stigmasterol (443 mg, 1.07 mmol, 1.80 equiv), and
TMSOTf (19.9 mg, 16.2 µL, 0.0894 mmol, 15.0 mol%) in CH2Cl2 (60 mL). Purifi-
cation by column chromatography (SiO2, n-pentane/EtOAc 3:1 → 1:1) afforded β-
glycoside 13 (191 mg, 0.185 mmol, 31%) and 2-deacetylated α-glycoside 16 (224 mg,
0.226 mmol, 38%) as pale yellow solids. Analytical data of the β-glycoside 13: TLC:
Rf = 0.3 (SiO2, n-hexane/EtOAc 1:1). 1H NMR (600 MHz, CDCl3): δ (ppm) = 0.69
(s, 3H), 0.77–0.82 (m, 7H), 0.84 (d, J = 6.4 Hz, 3H), 0.87–0.95 (m, 2H), 0.98 (s,
3H), 0.99–1.10 (m, 6H), 1.11–1.22 (m, 3H), 1.21–1.31 (m, 2H), 1.38–1.60 (m, 10H),
1.65–1.75 (m, 1H), 1.81–1.91 (m, 2H), 1.94–2.07 (m, 3H), 1.98 (s, 3H), 2.01 (s, 3H),
2.03 (s, 3H), 2.04 (s, 3H), 2.09 (s, 3H), 2.11 (s, 3H), 2.13–2.27 (m, 1H), 3.39–3.50 (m,
1H), 3.57 (ddd, J = 10.0, 5.2, 2.1 Hz, 1H), 3.66 (ddd, J = 10.0, 4.5, 2.3 Hz, 1H), 3.75
(dd, J = 9.9, 9.1 Hz, 1H), 4.04 (dd, J = 12.4, 2.3 Hz, 1H), 4.09 (dd, J = 11.9, 5.2 Hz,
1H), 4.37 (dd, J = 12.5, 4.5, 1H), 4.48 (dd, J = 12.4, 2.5 Hz, 1H), 4.50 (d, J = 7.9 Hz,
1H), 4.54 (d, J = 8.0 Hz, 1H), 4.87 (dd, J = 9.7, 8.0 Hz, 1H), 4.92 (dd, J = 9.4, 7.9 Hz,
1H), 5.01 (dd, J = 15.1, 8.8 Hz, 1H), 5.06 (t, J = 9.7 Hz, 1H), 5.11–5.20 (m, 3H),
5.34 (dt, J = 5.7, 2.0 Hz, 1H). 13C NMR (151 MHz, CDCl3): δ (ppm) = 12.0, 12.3,
19.0, 19.4, 20.6, 20.6, 20.7, 20.7, 20.9, 21.0, 21.1, 21.2, 24.3, 24.4, 25.4, 28.9, 29.4, 31.8,
31.9, 31.9, 36.7, 37.2, 38.9, 39.6, 40.5, 42.2, 50.1, 51.2, 55.9, 56.8, 61.6, 62.0, 67.8, 71.6,
71.7, 71.9, 72.6, 72.9, 76.6, 80.1, 99.5, 100.7, 122.1, 129.2, 138.3, 140.3, 169.0, 169.3,
169.8, 170.2, 170.3, 170.5. IR (ATR): v˜ (cm−1) = 2,960, 2,870, 1,742, 1,446, 1,365,
1,222, 1,040, 906, 759, 564. HRMS (ESI): m/z calcd. for C55H82O18Na+ [M+Na]+
1053.5393; found 1053.5398. Analytical data of the α-glycoside 16: TLC: Rf = 0.2
(SiO2, n-hexane/EtOAc 1:1). 1H NMR (600 MHz, CDCl3): δ (ppm) = 0.70 (s, 3H),
0.77–0.83 (m, 6H), 0.85 (d, J = 6.4 Hz, 3H), 0.88–0.96 (m, 1H), 0.96–1.09 (m, 9H),
1.10–1.22 (m, 3H), 1.22–1.31 (m, 1H), 1.38–1.59 (m, 9H), 1.65–1.75 (m, 1H), 1.83–
1.90 (m, 2H), 1.94–1.98 (m, 1H), 1.97–2.00 (m, 5H), 2.01 (s, 3H), 2.01–2.06 (m, 1H),
2.05 (s, 3H), 2.09 (s, 3H), 2.10 (s, 3H), 2.11 (s, 3H), 2.31–2.41 (m, 2H), 3.43–3.50 (m,
1H), 3.53 (ddd, J = 11.9, 9.8, 4.0 Hz, 1H), 3.59–3.64 (m, 1H), 3.66 (ddd, J = 9.8, 4.1,
2.3 Hz, 1H), 3.99 (ddd, J = 10.1, 5.4, 2.1 Hz, 1H), 4.05 (dd, J = 12.4, 2.4 Hz, 1H), 4.12
(dd, J = 11.9, 5.4 Hz, 1H), 4.39 (dd, J = 12.4, 4.1 , 1H), 4.43 (dd, J = 11.9, 2.1 Hz,
1H), 4.52 (d, J = 7.9 Hz, 1H), 4.94 (dd, J = 9.2, 7.9 Hz, 1H), 4.98 (d, J = 4.1 Hz,
1H), 5.02 (dd, J = 15.1, 8.8 Hz, 1H), 5.07–5.22 (m, 4H), 5.36 (d, J = 5.5 Hz, 1H).
13C NMR (151 MHz, CDCl3): δ (ppm) = 12.0, 12.2, 19.0, 19.3, 20.5, 20.6, 20.7, 20.9,

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33
21.0, 21.1, 21.2, 24.3, 25.4, 28.1, 28.9, 31.8, 31.9, 31.9, 36.6, 36.9, 39.6, 40.1, 40.5,
42.2, 50.1, 51.2, 55.9, 56.8, 61.6, 62.2, 67.7, 68.5, 71.0, 71.7, 71.8, 73.0, 73.2, 76.7,
79.4, 97.0, 100.8, 122.3, 129.2, 138.3, 140.2, 169.2, 169.2, 170.2, 170.4, 170.5, 170.7.
IR (ATR): v˜ (cm−1) = 3,480, 2,955, 2,871, 1,741, 1,458, 1,368, 1,223, 1,031, 906, 738,
599. IR (ATR): v˜ (cm−1) = 3,480, 2,955, 2,871, 1,741, 1,458, 1,368, 1,223, 1,031, 906,
738, 599. HRMS (ESI): m/z calcd. for C53H80O17Na+ [M+Na]+ 1011.5288; found
1011.5285.
Stigmasteryl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl
-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-D-glucopyranosides 14 and 17
Glycosylation was performed according to the general procedure using compound
10 (203 mg, 0.190 mmol, 1.00 equiv), stigmasterol (157 mg, 0.380 mmol, 2.00
equiv), and TMSOTf (6.33 mg, 5.16 µL, 0.0285 mmol, 15.0 mol%) in CH2Cl2
(19 mL). Purification by column chromatography (SiO2, n-pentane/EtOAc 2:1 →
1:1.5) afforded β-glycoside 14 (80.1 mg, 0.0607 mmol, 32%) and 2-deacetylated α-
glycoside 17 (101 mg, 0.0791 mmol, 42%) as pale yellow solids. Analytical data of the
β-glycoside 14: TLC: Rf = 0.5 (SiO2, n-hexane/EtOAc 1:1.5). 1H NMR (300 MHz,
CDCl3): δ (ppm) = 0.69 (s, 3H), 0.75–0.87 (m, 10H), 0.87–0.95 (m, 2H), 0.98 (s,
3H), 1.02 (d, J = 6.6 Hz, 3H), 1.03–1.12 (m, 1H), 1.09–1.32 (m, 6H), 1.37–1.59
(m, 10H), 1.61–1.78 (m, 1H), 1.77–1.92 (m, 2H), 1.98 (s, 3H), 1.98 (s, 3H), 1.99
(s, 3H), 2.01 (s, 3H), 2.02 (s, 3H), 2.03 (s, 3H), 2.03 (s, 3H), 2.09 (s, 3H), 2.11 (s,
3H), 2.14 (s, 3H), 2.16–2.25 (m, 2H), 3.36–3.51 (m, 1H), 3.52–3.68 (m, 3H), 3.75
(td, J = 9.4, 6.6 Hz, 2H), 3.98–4.17 (m, 3H), 4.29–4.46 (m, 2H), 4.44–4.57 (m,
4H), 4.80–4.96 (m, 3H), 4.97–5.21 (m, 6H), 5.34 (d, J = 5.0 Hz, 1H). 13C NMR
(101 MHz, CDCl3): δ (ppm) = 12.0, 12.2, 20.5, 20.5, 20.5, 20.6, 20.7, 20.7, 20.8,
20.9, 21.0, 21.1, 21.2, 24.3, 25.4, 25.9, 28.9, 29.4, 29.7, 30.2, 31.8, 31.9, 31.9, 33.5,
36.7, 37.2, 38.9, 39.6, 40.5, 42.2, 50.2, 51.2, 56.0, 56.8, 61.5, 61.9, 61.9, 62.2, 67.7,
71.6, 71.6, 71.8, 72.0, 72.5, 72.6, 72.7, 72.9, 76.2, 76.6, 77.2, 80.1, 99.5, 100.5, 100.8,
122.1, 129.3, 140.3, 169.1, 169.3, 169.5, 169.7, 169.8, 170.2, 170.3, 170.5. IR (ATR):
v˜ (cm−1) = 2,955, 2,936, 2,869, 1,743, 1,436, 1,367, 1,216, 1,216, 1,034, 904, 600.
HRMS (ESI) m/z calcd. for C67H98O26Na+ [M+Na]+ 1341.6239; found 1341.6237.
Analytical data of the α-glycoside 17: TLC: Rf = 0.3 (SiO2, n-hexane/EtOAc 1:1.5).
1H NMR (300 MHz, CDCl3): δ (ppm) = 0.70 (s, 3H), 0.75–0.89 (m, 9H), 0.86–0.97
(m, 1H), 0.97–1.06 (m, 8H), 1.08–1.33 (m, 5H), 1.33–1.61 (m, 11H), 1.62–1.81 (m,
1H), 1.80–1.93 (m, 2H), 1.90–2.00 (m, 1H), 1.98 (s, 3H), 1.97–2.05 (m, 7H), 2.03
(s, 3H), 2.04 (s, 3H), 2.06 (s, 3H), 2.09 (s, 3H), 2.11 (s, 3H), 2.14 (s, 3H), 2.31–2.40
(m, 2H) 3.39–3.54 (m, 2H), 3.53–3.69 (m, 3H), 3.80 (t, J = 9.4 Hz, 1H), 3.91–4.03
(m, 1H), 4.04 (dd, J = 13.0, 2.6 Hz, 1H), 4.08–4.18 (m, 2H), 4.30–4.49 (m, 3H), 4.49
(d, J = 7.8 Hz, 2H), 4.81–5.01 (m, 3H), 5.00–5.21 (m, 6H), 5.35 (d, J = 5.0 Hz,
1H). 13C NMR (101 MHz, CDCl3): δ (ppm) = 12.3, 12.5, 19.3, 19.6, 20.8, 20.8,
20.8, 20.9, 21.0, 21.1, 21.2, 21.2, 21.2, 21.3, 21.4, 21.5, 24.6, 25.7, 28.4, 29.2, 32.1,
32.2, 32.2, 36.9, 37.3, 39.9, 40.4, 40.8, 42.5, 50.4, 51.5, 56.2, 57.1, 61.8, 62.5, 62.5,
68.0, 68.8, 71.9, 72.2, 72.3, 72.9, 73.1, 73.2, 73.5, 76.4, 77.5, 79.6, 97.3, 101.0, 101.1,

34
K. KETTELHOIT AND D. B. WERZ
122.6, 129.6, 138.6, 140.5, 169.4, 169.6, 169.7, 170.1, 170.5, 170.5, 170.6, 170.8, 170.9.
IR (ATR): v˜ (cm−1) = 3,478, 2,956, 2,871, 1,741, 1,435, 1,367, 1,217, 1,032, 903,
599. HRMS (ESI): m/z calcd. for C65H96O25Na+ [M+Na]+ 1299.6133; found 1299.
6130.
Stigmasteryl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl
-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-
tri-O-acetyl-D-glucopyranosides 15 and 18
Glycosylation was performed according to the general procedure using compound
11 (220 mg, 0.162 mmol, 1.00 equiv), stigmasterol (134 mg, 0.324 mmol, 2.00
equiv), and TMSOTf (5.40 mg, 4.30 µL, 0.0243 mmol, 15.0 mol%) in CH2Cl2
(16 mL). Purification by column chromatography (SiO2, n-pentane/EtOAc 2:1 →
1:1.5) afforded β-glycoside 15 (72.1 mg, 0.0448 mmol, 28%) and 2-deacetylated α-
glycoside 18 (124 mg, 0.0792 mmol, 49%) as pale yellow solids. Analytical data of the
β-glycoside 15: TLC: Rf = 0.4 (SiO2, n-hexane/EtOAc 1:1.5). 1H NMR (600 MHz,
CDCl3): δ (ppm) = 0.69 (s, 3H), 0.77–0.82 (m, 6H), 0.84 (d, J = 6.3 Hz, 3H), 0.85–
0.96 (m, 2H), 0.97 (s, 3H), 0.97–1.04 (m, 4H), 1.02–1.11 (m, 1H), 1.10–1.22 (m, 3H),
1.22–1.35 (m, 4H), 1.37–1.60 (m, 9H), 1.65–1.75 (m, 1H), 1.80–1.90 (m, 2H), 1.95
(s, 3H), 1.97 (s, 3H), 1.98 (s, 3H), 1.99 (s, 3H), 2.01 (s, 3H), 2.01 (s, 3H), 2.02 (s,
3H), 2.03 (s, 3H), 2.03 (s, 3H), 2.09 (s, 3H), 2.11 (s, 3H), 2.14 (s, 3H), 2.14 (s, 3H),
2.16–2.28 (m, 2H), 3.39–3.48 (m, 1H), 3.53–3.60 (m, 3H), 3.63 (ddd, J = 9.9, 4.4,
2.3 Hz, 1H), 3.70–3.78 (m, 3H), 4.03 (dd, J = 12.5, 2.2 Hz, 1H), 4.05–4.12 (m, 3H),
4.35 (dd, J = 12.5, 4.3 Hz, 1H), 4.40 (dd, J = 12.2, 2.0 Hz, 2H), 4.42–4.50 (m, 4H),
4.53 (d, J = 8.0 Hz, 1H), 4.80–4.88 (m, 3H), 4.90 (dd, J = 9.3, 7.9 Hz, 1H), 4.98–
5.18 (m, 7H), 5.34 (d, J = 5.5 Hz, 1H). 13C NMR (151 MHz, CDCl3): δ = 12.0, 12.2,
18.9, 19.3, 20.4, 20.4, 20.5, 20.5, 20.5, 20.5, 20.6, 20.7, 20.7, 20.9, 21.0, 21.0, 21.2, 24.3,
25.4, 28.9, 29.4, 29.6, 31.8, 31.8, 31.8, 36.6, 37.1, 38.8, 39.6, 40.4, 42.1, 50.1, 51.2, 55.9,
56.8, 61.4, 61.9, 62.0, 62.1, 67.6, 71.5, 71.6, 71.7, 71.8, 72.0, 72.4, 72.5, 72.5, 72.6, 72.6,
72.7, 72.8, 76.0, 76.2, 76.5, 80.0, 99.4, 100.4, 100.5, 100.7, 122.1, 129.2, 138.2, 140.2,
169.0, 169.2, 169.2, 169.3, 169.5, 169.7, 169.8, 170.1, 170.1, 170.3, 170.4. IR (ATR):
v˜ (cm−1) = 2,957, 2,936, 2,869, 1,739, 1,435, 1,369, 1,215, 1,034, 903, 601. HRMS
(ESI): m/z calcd. for C79H114O34Na+ [M+Na]+ 1629.7084; found 1629.7084. Ana-
lytical data of the α-glycoside 18: TLC: Rf = 0.2 (SiO2, n-hexane/EtOAc 1:1.5). 1H
NMR (600 MHz, CDCl3): δ = 0.70 (s, 3H), 0.77–0.83 (m, 6H), 0.84 (d, J = 6.4 Hz,
3H), 0.88–0.96 (m, 2H), 0.97–1.11 (m, 9H), 1.11–1.22 (m, 3H), 1.21–1.31 (m, 2H),
1.36–1.59 (m, 9H), 1.65–1.75 (m, 2H), 1.82–1.91 (m, 2H), 1.96 (s, 3H), 1.98 (s, 3H),
1.99 (s, 3H), 2.01 (s, 3H), 2.02 (s, 3H), 2.04 (s, 6H), 2.05 (s, 3H), 2.09 (s, 3H), 2.11
(s, 3H), 2.14 (s, 3H), 2.15 (s, 3H), 2.28–2.42 (m, 2H), 3.40–3.49 (m, 1H), 3.51 (ddd,
J = 11.8, 9.8, 4.0 Hz, 1H), 3.53–3.62 (m, 3H), 3.63 (ddd, J = 9.9, 4.3, 2.3 Hz, 1H),
3.72–3.81 (m, 2H), 3.97 (ddd, J = 10.0, 5.3, 2.1 Hz, 1H), 4.03 (dd, J = 12.5, 2.3 Hz,
1H), 4.06–4.13 (m, 3H), 4.36 (dd, J = 12.5, 4.4 Hz, 1H), 4.37–4.45 (m, 3H), 4.45 (d,
J = 7.8 Hz, 1H), 4.47 (dd, J = 7.9, 1.1 Hz, 2H), 4.80–4.85 (m, 1H), 4.83–4.86 (m,
1H), 4.90 (dd, J = 9.3, 7.9 Hz, 1H), 4.97 (d, J = 4.0 Hz, 1H), 4.99–5.19 (m, 8H),

JOURNAL OF CARBOHYDRATE CHEMISTRY
35
5.35 (d, J = 5.7 Hz, 1H). 13C NMR (151 MHz, CDCl3): δ (ppm) = 12.0, 12.2, 18.9,
19.3, 20.4, 20.5, 20.5, 20.5, 20.6, 20.6, 20.6, 20.8, 20.8, 20.8, 20.9, 21.0, 21.1, 21.2, 24.3,
25.4, 28.1, 28.9, 31.8, 31.8, 31.9, 36.6, 36.9, 39.6, 40.0, 40.5, 42.2, 50.1, 51.2, 55.9, 56.8,
61.4, 62.0, 62.1, 62.1, 67.7, 68.5, 71.0, 71.5, 71.7, 71.9, 72.0, 72.6, 72.6, 72.7, 72.7, 72.8,
73.1, 76.0, 76.1, 76.7, 79.3, 96.9, 100.5, 100.6, 100.8, 122.3, 129.2, 138.3, 140.2, 169.1,
169.3, 169.3, 169.4, 169.7, 169.7, 170.1, 170.2, 170.2, 170.4, 170.5, 170.7. IR (ATR):
v˜ (cm−1) = 3,450, 2,956, 2,870, 1,741, 1,435, 1,367, 1,214, 1,031, 903, 600. HRMS
(ESI): m/z calcd. for C77H112O33Na+ [M+Na]+ 1587.6978; found 1587.6977.
Stigmasteryl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-
acetyl-β-D-glucopyranoside (23)
Deprotection of 13 (171 mg, 0.166 mmol, 1.00 equiv) was performed according to
the general procedure in MeOH (12.5 mL) and CH2Cl2 (4.2 mL). Dialysis for 5 d
and lyophilization afforded the desired product 23 (110 mg, 0.149 mmol, 90%) as
a white powder. 1H NMR (600 MHz, DMSO-d6): δ = 0.67 (s, 3H), 0.74–0.80 (m,
6H), 0.82 (d, J = 6.3 Hz, 3H), 0.85–0.93 (m, 1H), 0.96 (s, 3H), 1.00 (d, J = 6.6 Hz,
6H), 1.09–1.20 (m, 3H), 1.20–1.28 (m, 1H), 1.34–1.45 (m, 3H), 1.46–1.57 (m, 6H),
1.59–1.70 (m, 1H), 1.76–1.85 (m, 2H), 1.88–1.97 (m, 2H), 1.98–2.06 (m, 1H), 2.13
(t, J = 11.8 Hz, 1H), 2.37 (ddd, J = 13.6, 5.0, 2.0 Hz, 1H), 2.93–3.02 (m, 2H), 3.05
(td, J = 9.2, 5.4 Hz, 1H), 3.14 (dd, J = 8.9, 5.0 Hz, 1H), 3.17–3.22 (m, 1H), 3.23–3.33
(m, 3H), 3.40 (dt, J = 12.0, 6.3 Hz, 1H), 3.41–3.50 (m, 1H), 3.55–3.62 (m, 1H), 3.66–
3.75 (m, 2H), 4.25 (d, J = 7.9 Hz, 1H), 4.29 (d, J = 7.8 Hz, 1H), 4.53 (t, J = 6.0 Hz,
1H), 4.60 (dd, J = 5.9, 4.9, 1H), 4.66 (d, J = 1.7 Hz, 1H), 4.99 (d, J = 5.6 Hz, 1H),
5.01–5.05 (m, 3H), 5.15 (dd, J = 15.1, 8.7 Hz, 1H), 5.24 (d, J = 4.9 Hz, 1H), 5.30–
5.35 (m, 1H). 13C NMR (151 MHz, DMSO-d6): δ = 11.8, 12.1, 18.9, 19.1, 20.6, 21.0,
21.1, 23.9, 24.9, 28.5, 29.2, 31.4, 31.4, 31.4, 36.2, 36.8, 38.3, 40.0, 40.0, 41.7, 49.6, 50.6,
55.3, 56.3, 60.5, 61.0, 70.0, 73.1, 73.3, 74.7, 75.0, 76.4, 76.8, 77.2, 80.7, 100.6, 103.2,
121.2, 128.8, 138.0, 140.4. IR (ATR): v˜ (cm−1) = 3,379, 3,934, 2,901, 2,868, 1,643,
1,460, 1,367, 1,022. Optical rotation: [α]2D5 = −41.1°(c 0.98, DMSO). HRMS (ESI):
m/z calcd. for C41H68O11Na+ [M+Na]+ 759.4654; found 759.4653.
Stigmasteryl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl
-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-glucopyranoside (24)
Deprotection of 14 (80.0 mg, 0.0606 mmol, 1.00 equiv) was performed according
to the general procedure in MeOH (4.5 mL) and CH2Cl2 (1.5 mL). Dialysis for 5
d and lyophilization afforded the desired product 24 (50.3 mg, 0.0559 mmol, 92%)
1
as a light grey powder. H NMR (600 MHz, DMSO-d6): δ (ppm) = 0.67 (s, 3H),
0.74–0.80 (m, 6H), 0.82 (d, J = 6.2 Hz, 3H), 0.89 (td, J = 11.3, 4.5 Hz, 2H), 0.96
(s, 3H), 1.00 (d, J = 6.5 Hz, 6H), 1.08–1.20 (m, 3H), 1.20–1.29 (m, 2H), 1.34–
1.57 (m, 10H), 1.58–1.69 (m, 1H), 1.75–1.86 (m, 2H), 1.86–1.99 (m, 2H), 1.98–
2.08 (m, 1H), 2.13 (t, J = 11.6 Hz, 1H), 2.33–2.41 (m, 1H), 2.93–3.02 (m, 2H),

36
K. KETTELHOIT AND D. B. WERZ
3.01–3.10 (m, 2H), 3.12–3.18 (m, 1H), 3.18–3.22 (m, 1H), 3.26–3.33 (m, 3H), 3.37–
3.43 (m, 1H), 3.42–3.50 (m, 1H), 3.52–3.62 (m, 2H), 3.67–3.75 (m, 2H), 3.78 (dd,
J = 9.4, 4.7 Hz, 1H), 4.24 (d, J = 7.9 Hz, 1H), 4.29 (d, J = 7.8 Hz, 1H), 4.32 (d,
J = 7.9 Hz, 1H), 4.54 (t, J = 6.0 Hz, 1H), 4.57–4.63 (m, 2H), 4.67 (t, J = 5.6 Hz,
1H), 4.74 (d, J = 1.8 Hz, 1H), 4.97–5.06 (m, 4H), 5.15 (dd, J = 15.1, 8.7 Hz,
1H), 5.24 (d, J = 5.0 Hz, 1H), 5.32 (s, 1H), 5.41 (d, J = 4.9 Hz, 1H). 13C NMR
(151 MHz, DMSO-d6): δ (ppm) = 11.8, 12.1, 18.9, 19.1, 20.6, 21.0, 21.1, 23.9, 24.9,
28.5, 29.2, 31.3, 31.4, 36.2, 36.8, 38.3, 40.0, 40.0, 41.7, 49.6, 50.6, 55.3, 56.3, 60.3,
60.4, 61.0, 70.0, 73.0, 73.1, 73.2, 74.7, 74.8, 75.0, 76.4, 76.8, 77.2, 80.4, 80.6, 100.6,
102.8, 103.2, 121.2, 128.8, 138.0, 140.4. IR (ATR): v˜ (cm−1) = 3,373, 2,933, 2,869,
1,644, 1,459, 1,368, 1,159, 1,022, 898, 564. Optical rotation: [α]2D5 = −36.9° (c 0.94,
DMSO). HRMS (ESI): m/z calcd. for C47H78O16Na+ [M+Na]+ 921.5182; found
921.5185.
Stigmasteryl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl
-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-
tri-O-acetyl-β-D-glucopyranoside (25)
Deprotection of 15 (72.0 mg, 0.0448 mmol, 1.00 equiv) was performed according
to the general procedure in MeOH (3.5 mL) and CH2Cl2 (1.1 mL). Dialysis for 3 d
and lyophilization afforded the desired product 25 (43.1 mg, 0.0406 mmol, 91%) as
a white powder. 1H NMR (600 MHz, DMSO-d6): δ (ppm) = 0.67 (s, 3H), 0.73–0.80
(m, 6H), 0.82 (d, J = 6.2 Hz, 3H), 0.85–0.93 (m, 1H), 0.93–1.08 (m, 9H), 1.09–1.20
(m, 3H), 1.20–1.30 (m, 3H), 1.34–1.45 (m, 3H), 1.45–1.58 (m, 5H), 1.59–1.71 (m,
1H), 1.75–1.87 (m, 2H), 1.87–1.99 (m, 2H), 1.98–2.07 (m, 1H), 2.09–2.18 (m, 1H),
2.37 (dd, J = 13.4, 4.5 Hz, 1H), 2.93–3.02 (m, 2H), 3.02–3.11 (m, 3H), 3.15 (t, J =
8.9, 1H), 3.17–3.23 (m, 1H), 3.23–3.35 (m, 7H), 3.39–3.54 (m, 3H), 3.53–3.64 (m,
3H), 3.67–3.76 (m, 2H), 3.79 (d, J = 11.1 Hz, 2H), 4.24 (d, J = 7.8 Hz, 1H), 4.29 (d, J
= 7.8 Hz, 1H), 4.32 (dd, J = 7.8, 3.9 Hz, 2H), 4.55 (t, J = 6.0 Hz, 1H), 4.58–4.65 (m,
2H), 4.66–4.74 (m, 3H), 4.78 (s, 1H), 4.95–5.10 (m, 3H), 5.10–5.21 (m, 2H), 5.28 (s,
1H), 5.30–5.35 (m, 1H), 5.43 (d, J = 4.9 Hz, 2H). 13C NMR (151 MHz, DMSO-d6):
δ (ppm) = 11.9, 12.1, 18.9, 19.1, 20.6, 21.0, 21.1, 23.9, 24.9, 28.5, 29.2, 31.4, 31.4,
36.2, 36.8, 38.3, 40.0, 40.0, 41.7, 49.6, 50.6, 55.3, 56.3, 60.3, 60.3, 60.4, 61.0, 70.0,
73.0, 73.0, 73.1, 73.2, 74.7, 74.7, 74.8, 75.0, 76.4, 76.8, 77.2, 80.3, 80.4, 80.6, 100.6,
102.8, 103.2, 121.2, 128.8, 138.0, 140.4. IR (ATR): v˜ (cm−1) = 3,361, 2,931, 2,891,
2,869, 1,663, 1,446, 1,368, 1,159, 1,022, 900. Optical rotation [α]2D5 = −40.5° (c 0.80,
DMSO). HRMS (ESI): m/z calcd. for C53H88O21Na+ [M+Na]+ 1083.5710: found
1083.5712.
Stigmasteryl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-
acetyl-α-D-glucopyranoside (26)
Deprotection of 16 (75.0 mg, 0.0727 mmol, 1.00 equiv) was performed according
to the general procedure in MeOH (5.4 mL) and CH2Cl2 (1.8 mL). Dialysis for 4

JOURNAL OF CARBOHYDRATE CHEMISTRY
37
d and lyophilization afforded the desired product 26 (42.7 mg, 0.0579 mmol, 80%)
1
as a white powder. H NMR (600 MHz, DMSO-d6): δ = 0.67 (s, 3H), 0.74–0.80
(m, 6H), 0.82 (d, J = 6.1 Hz, 3H), 0.86–0.93 (m, 1H), 0.96 (s, 3H), 1.00 (d, J =
6.6 Hz, 6H), 1.09–1.20 (m, 3H), 1.20–1.29 (m, 2H), 1.33–1.45 (m, 4H), 1.45–1.58
(m, 5H), 1.59–1.70 (m, 1H), 1.76–1.99 (m, 4H), 1.98–2.08 (m, 1H), 2.20–2.28 (m,
1H), 2.27–2.35 (m, 1H), 2.95–3.03 (m, 1H), 3.03–3.10 (m, 1H), 3.11–3.24 (m, 3H),
3.27–3.33 (m, 1H), 3.41 (dt, J = 11.9, 6.2 Hz, 1H), 3.51 (td, J = 9.1, 8.7, 2.1 Hz,
1H), 3.59 (dd, J = 9.7, 3.5 Hz, 1H), 3.61–3.67 (m, 2H), 3.67–3.73 (m, 1H), 4.22 (d,
J = 7.9 Hz, 1H), 4.49 (d, J = 2.4 Hz, 1H), 4.55 (t, J = 6.1 Hz, 1H), 4.58 (t, J =
5.4 Hz, 1H), 4.70 (d, J = 6.6 Hz, 1H), 4.78 (d, J = 3.7 Hz, 1H), 4.99 (d, J = 5.5 Hz,
1H), 5.02 (d, J = 4.9 Hz, 2H), 5.15 (dd, J = 15.1, 8.7 Hz, 1H), 5.21 (d, J = 4.8 Hz,
1H), 5.27–5.33 (m, 1H). 13C NMR (151 MHz, DMSO-d6) δ = 11.9, 12.1, 18.9, 19.1,
20.6, 21.0, 21.1, 23.9, 24.9, 27.3, 28.5, 31.4, 31.4, 36.2, 36.6, 40.0, 40.0, 41.7, 49.6,
50.6, 55.4, 56.3, 60.2, 61.0, 70.0, 70.7, 71.5, 71.5, 73.3, 76.4, 76.5, 76.5, 76.5, 76.8,
80.6, 96.6, 103.1, 121.1, 128.8, 138.0, 140.6. IR (ATR): v˜ (cm−1) = 3,404, 2,932,
2,868, 1,460, 1,369, 1,154, 1,023, 774. Optical rotation: [α]2D5 = 33.9°(c 1.00, DMSO).
HRMS (ESI): m/z calcd. for C41H68O11Na+ [M+Na]+ 759.4654; found 759.
4653.
Stigmasteryl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-
acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-α-D-glucopyranoside (27)
Deprotection of 17 (100 mg, 0.0783 mmol, 1.00 equiv) was performed according
to the general procedure in MeOH (5.8 mL) and CH2Cl2 (2.0 mL). Dialysis for 5 d
and lyophilization afforded the desired product 27 (61.3 mg, 0.0682 mmol, 87%) as
a white powder. 1H NMR (600 MHz, DMSO-d6): δ (ppm) = 0.67 (s, 3H), 0.73–0.81
(m, 6H), 0.82 (d, J = 6.3 Hz, 3H), 0.85–0.93 (m, 1H), 0.93–1.08 (m, 9H), 1.08–1.20
(m, 3H), 1.19–1.28 (m, 2H), 1.34–1.46 (m, 4H), 1.46–1.57 (m, 5H), 1.59–1.70 (m,
1H), 1.77–1.98 (m, 4H), 2.02 (dd, J = 15.5, 9.1 Hz, 1H), 2.21–2.28 (m, 1H), 2.27–
2.34 (m, 1H), 2.96–3.02 (m, 1H), 3.01–3.10 (m, 2H), 3.15 (td, J = 8.8, 5.0 Hz, 1H),
3.18–3.24 (m, 2H), 3.28–3.34 (m, 3H), 3.38–3.43 (m, 2H), 3.52 (td, J = 8.8, 1.9 Hz,
1H), 3.55–3.62 (m, 2H), 3.61–3.67 (m, 2H), 3.67–3.73 (m, 1H), 3.75–3.82 (m, 1H),
4.24 (d, J = 7.9 Hz, 1H), 4.29 (d, J = 7.9 Hz, 1H), 4.42 (d, J = 2.1 Hz, 1H), 4.55 (t, J
= 6.0 Hz, 1H), 4.60 (t, J = 5.4 Hz, 1H), 4.66 (t, J = 5.5 Hz, 1H), 4.70 (d, J = 6.7 Hz,
1H), 4.74 (d, J = 1.6 Hz, 1H), 4.78 (d, J = 3.8 Hz, 1H), 4.97–5.06 (m, 3H), 5.15 (dd,
J = 15.1, 8.7 Hz, 1H), 5.24 (d, J = 4.9 Hz, 1H), 5.30 (s, 1H), 5.37 (d, J = 4.9 Hz,
1H). 13C NMR (151 MHz, DMSO-d6) δ (ppm) = 11.9, 12.1, 18.9, 19.1, 20.6, 21.0,
21.1, 23.9, 24.9, 27.3, 28.5, 31.4, 31.4, 36.2, 36.6, 40.0, 40.0, 41.7, 49.6, 50.6, 55.3, 56.3,
60.1, 60.3, 61.0, 70.0, 70.7, 71.5, 71.5, 73.0, 73.2, 74.7, 74.8, 76.5, 76.8, 80.4, 80.6, 96.6,
102.7, 103.2, 121.1, 128.8, 138.0, 140.6. IR (ATR): v˜ (cm−1) = 3,386, 2,933, 2,869,
1,460, 1,369, 1,161, 1,021, 900, 563. Optical rotation:[α]2D5 = 17.9° (c 1.25, DMSO).
HRMS (ESI): m/z calcd. for C47H78O16Na+ [M+Na]+ 921.5182; found 921.
5182.

38
K. KETTELHOIT AND D. B. WERZ
Stigmasteryl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-
acetyl-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-acetyl-β-D-glucopyranosyl-(1→4)-
2,3,6-tri-O-acetyl-α-D-glucopyranoside (28)
Deprotection of 18 (124 mg, 0.0792 mmol, 1.00 equiv) was performed according
to the general procedure in MeOH (6.0 mL) and CH2Cl2 (3.0 mL). Dialysis for 3 d
and lyophilization afforded the desired product 28 (61.0 mg, 0.0575 mmol, 73%) as
a white powder. 1H NMR (600 MHz, DMSO-d6): δ (ppm) = 0.67 (s, 3H), 0.74–0.80
(m, 6H), 0.82 (d, J = 6.2 Hz, 3H), 0.85–0.93 (m, 1H), 0.93–1.06 (m, 9H), 1.09–1.20
(m, 3H), 1.20–1.30 (m, 2H), 1.33–1.45 (m, 4H), 1.45–1.58 (m, 5H), 1.59–1.71 (m,
1H), 1.75–2.00 (m, 4H), 1.99–2.08 (m, 1H), 2.24 (t, J = 11.6 Hz, 1H), 2.27–2.40 (m,
1H), 2.94–3.02 (m, 1H), 3.02–3.11 (m, 3H), 3.12–3.18 (m, 1H), 3.17–3.24 (m, 2H),
3.27–3.35 (m, 5H), 3.36–3.45 (m, 3H), 3.49–3.56 (m, 1H), 3.55–3.62 (m, 3H), 3.61–
3.67 (m, 2H), 3.67–3.73 (m, 1H), 3.79 (dd, J = 10.1, 4.8 Hz, 2H), 4.24 (d, J = 7.9 Hz,
1H), 4.29 (d, J = 7.8 Hz, 1H), 4.32 (d, J = 7.9 Hz, 1H), 4.43 (d, J = 2.2 Hz, 1H),
4.55 (t, J = 6.0 Hz, 1H), 4.60 (t, J = 5.3 Hz, 1H), 4.63–4.69 (m, 3H), 4.70 (d, J =
6.7 Hz, 1H), 4.75 (d, J = 1.7 Hz, 1H), 4.78 (d, J = 3.7 Hz, 1H), 4.97–5.07 (m, 3H),
5.15 (dd, J = 15.1, 8.7 Hz, 1H), 5.24 (d, J = 5.0 Hz, 1H), 5.30 (s, 1H), 5.37 (d, J =
4.9 Hz, 1H), 5.41 (d, J = 5.1 Hz, 1H). 13C NMR (151 MHz, DMSO-d6): δ (ppm) =
11.9, 12.1, 18.9, 19.1, 20.6, 21.0, 21.1, 23.9, 24.9, 27.3, 28.5, 31.4, 31.4, 36.2, 36.6, 40.0,
41.7, 49.6, 50.6, 55.3, 56.3, 60.2, 60.3, 60.3, 61.0, 70.0, 70.7, 71.5, 71.5, 73.0, 73.0, 73.2,
74.7, 74.8, 76.5, 76.8, 80.3, 80.4, 80.6, 96.6, 102.8, 102.8, 103.2, 121.1, 128.8, 138.0,
140.6. IR (ATR): IR (ATR): v˜ (cm−1) = 3,389, 2,932, 2,904, 2,869, 1,457, 1,371, 1,160,
1,021, 900, 555. Optical rotation [α]2D5 = 31.7° (c 0.80, DMSO). HRMS (ESI): m/z
calcd. for C53H88O21Na+ [M+Na]+ 1083.5716; found 1083.5727.
Stigmasteryl acetate 22a
TLC: Rf = 0.8 (SiO2, n-hexane/EtOAc 1:1.5). 1H NMR (300 MHz, CDCl3): δ (ppm)
= 0.70 (s, 3H), 0.75–0.90 (m, 9H), 0.98–1.07 (m, 8H), 1.10–1.30 (m, 6H), 1.34–
1.47 (m, 2H), 1.45–1.61 (m, 7H), 1.63–1.76 (m, 1H), 1.79–1.92 (m, 2H), 1.91–2.11
(m, 6H), 2.27–2.37 (m, 2H), 4.52–4.69 (m, 1H), 5.01 (dd, J = 15.2, 8.5 Hz, 1H),
5.16 (dd, J = 15.2, 8.4 Hz, 1H), 5.34–5.42 (m, 1H). 13C NMR (75 MHz, CDCl3): δ
(ppm) = 12.0, 12.3, 19.0, 19.3, 21.0, 21.1, 21.2, 21.4, 24.4, 25.4, 27.8, 28.9, 31.9, 31.9,
36.6, 37.0, 38.1, 39.6, 40.5, 42.2, 50.1, 51.2, 55.9, 56.8, 74.0, 77.2, 122.6, 129.3, 138.3,
139.6, 170.5. HRMS (ESI): m/z calcd. for C31H50O2Na+ [M+Na]+ 477.3703; found
477.3705.
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