Radiosynthesis of 18F-labeled D-allose

Article abstract of DOI:10.1016/j.carres.2019.107827

Rare sugars are defined as monosaccharides that exist in nature but are only present in limited quantities. D-Allose is a rare sugar that has been reported to have some unique physiological effects. The present study describes suitable synthetic procedures for novel rare sugars of D-allose that are ¹⁸F-labeled at the C-3 and C-6 positions and the preparation of the appropriate labeling precursors. The goal is to facilitate in vivo, noninvasive positron emission tomography (PET) investigation of the behavior of rare sugar analogs of D-allose in organs. We found five precursors that were practical for labeling, three for 3-deoxy-3-[¹⁸F]fluoro-D-allose ([¹⁸F]3FDA) and two for 6-deoxy-6-[¹⁸F]fluoro-D-allose ([¹⁸F]6FDA). With manual operation synthesis, the highest radiochemical conversion rates were 75% for [¹⁸F]3FDA with a precursor of 1,2,4,6-tetra-O-acetyl-3-O-trifluoromethanesulfonyl-β-D-glucopyranose and 69% for [¹⁸F]6FDA with a precursor of 1,2,3,4-tetra-O-acetyl-6-O-trifluoromethanesulfonyl-β-D-allopyranose. Furthermore, the practical yields of [¹⁸F]3FDA and [¹⁸F]6FDA using an automated synthesizer were also investigated. Radiochemical yields of 67% and 49% were obtained for [¹⁸F]3FDA and [¹⁸F]6FDA, respectively, in an automated synthesizer. As basic assessment of stability for use in PET scanning, high performance liquid chromatography analysis showed no decomposition of [¹⁸F]3FDA and [¹⁸F]6FDA after up to 6 h in rabbit blood plasma.

Full text of DOI:10.1016/j.carres.2019.107827

Journal Pre-proof
18
Radiosynthesis of F-labeled d-allose
Hiroyuki Yamamoto, Kenji Wada, Jun Toyohara, Tetsuro Tago, Masanobu Ibaraki,
Toshibumi Kinoshita, Yuka Yamamoto, Yoshihiro Nishiyama, Nobuyuki Kudomi
PII:
S0008-6215(19)30438-0
DOI:
https://doi.org/10.1016/j.carres.2019.107827
CAR 107827
Reference:
To appear in: Carbohydrate Research
Received Date: 16 August 2019
Revised Date: 25 September 2019
Accepted Date: 26 September 2019
Please cite this article as: H. Yamamoto, K. Wada, J. Toyohara, T. Tago, M. Ibaraki, T. Kinoshita, Y.
18
Yamamoto, Y. Nishiyama, N. Kudomi, Radiosynthesis of F-labeled d-allose, Carbohydrate Research
(2019), doi: https://doi.org/10.1016/j.carres.2019.107827.
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Radiosynthesis of 18F-labeled D-allose
Hiroyuki Yamamotoa,b*, Kenji Wadac, Jun Toyoharad, Tetsuro Tagod, Masanobu Ibarakib, Toshibumi
Kinoshitab, Yuka Yamamotoe, Yoshihiro Nishiyamae, Nobuyuki Kudomia
Types of paper: Full Papers
a Department of Medical Physics, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho,
Kita-gun, Kagawa 761-0793, Japan
b
Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels,
6-10 Senshukubota-machi, Akita-shi, Akita 010-0874, Japan
c
Department of Chemistry for Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe,
Miki-cho, Kita-gun, Kagawa 761-0793, Japan
d
Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho,
Itabashi-ku, Tokyo 173-0015, Japan
e
Department of Radiology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho,
Kita-gun, Kagawa 761-0793, Japan

Corresponding author.
E-mail address: yamamoto-hiroyuki@akita-noken.jp (H. Yamamoto)
Full postal address: Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain
and Blood Vessels, 6-10 Senshukubota-machi, Akita-shi, Akita 010-0874, Japan
ABSTRACT
Rare sugars are defined as monosaccharides that exist in nature but are only present in limited quantities.
D-Allose is a rare sugar that has been reported to have some unique physiological effects. The present
18
study describes suitable synthetic procedures for novel rare sugars of D-allose that are F-labeled at the
C-3 and C-6 positions and the preparation of the appropriate labeling precursors. The goal is to facilitate
in vivo, noninvasive positron emission tomography (PET) investigation of the behavior of rare sugar
analogs of D-allose in organs. We found five precursors that were practical for labeling, three for
3-deoxy-3-[18F]fluoro-D-allose ([18F]3FDA) and two for 6-deoxy-6-[18F]fluoro-D-allose ([18F]6FDA).
With manual operation synthesis, the highest radiochemical conversion rates were 75% for [18F]3FDA
with a precursor of 1,2,4,6-tetra-O-acetyl-3-O-trifluoromethanesulfonyl-β-D-glucopyranose and 69% for
[18F]6FDA with a precursor of 1,2,3,4-tetra-O-acetyl-6-O-trifluoromethanesulfonyl-β-D-allopyranose.
Furthermore, the practical yields of [18F]3FDA and [18F]6FDA using an automated synthesizer were also
investigated. Radiochemical yields of 67% and 49% were obtained for [18F]3FDA and [18F]6FDA,

respectively, in an automated synthesizer. As basic assessment of stability for use in PET scanning, high
performance liquid chromatography analysis showed no decomposition of [18F]3FDA and [18F]6FDA
after up to 6 h in rabbit blood plasma.
Keywords:
Rare
sugar;
3-Deoxy-3-[18F]fluoro-D-allose;
6-Deoxy-6-[18F]fluoro-D-allose;
Fluorine-18;
Radiochemical synthesis; PET tracer
Graphical abstract:
O
OH
OH
O
OH
OH
HO
18F
HO
HO
18F
OH
3-Deoxy-3-[18F]fluoro-D-allose
([18F]3FDA)
6-Deoxy-6-[18F]fluoro-D-allose
([18F]6FDA)
1. Introduction
D-Allose is a rare sugar and an epimer of D-glucose at the C-3 position. Therapeutic applications
of D-allose that have recently been the subject of research include protection of neurons from ischemic
insult [1,2], a growth inhibitory effect on cancer cells [3–6], and enhancement of anticancer agents [7–10].

At the cell level, some of the mechanisms of those effects have been revealed. For example, the
anticancer mechanism may include up-regulation of thioredoxin interacting protein [4] and
down-regulation of glucose transporter type 1 [6], but other mechanisms are not known, particularly at the
organ level.
Regarding
sugar
compounds,
18F-labeled
D-glucose
at
the
C-2
position,
2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG), is widely applied for assessment of tumors [11–13],
functional activity of tissue in organs such as the brain [14–16], and inflammation of the heart [17] or
aortic wall [18], in conjunction with positron emission tomography (PET). This means that the labeled
compound plays an important role in revealing the mechanisms of pathophysiological processes at the
organ level.
18F-labeled compounds at the different positions of C-3 (3-deoxy-3-[18F]fluoro-D-glucose:
[18F]3FDG) [19] and C-6 (6-deoxy-6-[18F]fluoro-D-glucose: [18F]6FDG) [20], as D-glucose analogs, were
also synthesized, and the characteristics of these compounds were demonstrated.
It is also of interest to label D-allose with radioisotopes to investigate their behavior in organs in
vivo. In previous reports [21,22], 2-deoxy-2-[18F]fluoro-D-allose was synthesized with electrophilic
fluorination, and it was demonstrated that it can act as a PET tracer for tumor imaging with higher tumor
to blood ratios and lower physiological uptake in the brain than [18F]FDG.
D-glucose analogs have been labeled at different positions, and [18F]3FDG [19] and [18F]6FDG

[20] showed different behavior in organs from [18F]FDG. Biodistribution of [18F]3FDG on mouse, rat,
and dog revealed to have smaller lumped-constant of brain and slower blood clearance than [18F]FDG
[23]. EMT6 tumor (mouse mammary gland tumor cells) imaging of [18F]6FDG on mouse demonstrated
that [18F]6FDG is a potential tracer for glucose transport only unlike [18F]FDG [24]. Difference of labeled
position of [18F]3FDG and [18F]6FDG causes different properties from [18F]FDG, thus, it would be of
interest and importance to reveal the dependence of their behavior on the labeled position of the D-allose
analog.
Along these lines, the present study aims to introduce 18F radioisotopes at C-3 and C-6 to
D-allose, namely, 3-deoxy-3-[18F]fluoro-D-allose ([18F]3FDA: [18F]1) and 6-deoxy-6-[18F]fluoro-D-allose
([18F]6FDA: [18F]2), respectively. [18F]6FDA may be expected never to become 6-phosphate analog in
vivo, and [18F]3FDA might be expected to have similar properties with 3-deoxy-D-glucose which is a
same compound with 3-deoxy-D-allose.
We designed some possible synthetic routes and assessed their merit by radiochemical
conversions (RCCs) and length of reaction time using manual operation synthesis. After the best
precursors were found, for future synthesis of [18F]3FDA and [18F]6FDA with sufficient quality, practical
yields with these precursors were also investigated using an automated synthesizer. Because of the 109.8
min physical half-life of 18F, it is desirable that labeling and hydrolytic deprotection reactions in
automated synthesizers proceed within approximately 1–2 physical half-lives, with reasonable percent

yields of at least approximately 50%.
2.
Results and discussion
2.1
Preparation of precursors and non-radioactive authentic standards
As possible synthetic routes, an SN2 reaction of no-carrier-added [18F]fluoride to triflate
precursors with protecting groups on the non-reacting positions was adopted as the [18F]fluorination
reaction, and then the protecting groups were eliminated by a hydrolysis reaction. Five precursors were
practical for labeling: 1,2:5,6-di-O-isopropylidene-3-O-trifluoromethanesulfonyl-α-D-glucofuranose (3),
1,2,4,6-tetra-O-acetyl-3-O-trifluoromethanesulfonyl-β-D-glucopyranose
1,2,4,6-tetra-O-benzoyl-3-O-trifluoromethanesulfonyl-β-D-glucopyranose (4b) for [18F]3FDA and
1,2,3,4-tetra-O-acetyl-6-O-trifluoromethanesulfonyl-β-D-allopyranose (5a), and
1,2,3,4-tetra-O-benzoyl-6-O-trifluoromethanesulfonyl-β-D-allopyranose (5b) for [18F]6FDA.
(4a),
and
In this context, pyranose-type precursors of [18F]3FDA, 4a and 4b, were first prepared from
1,2,4,6-tetra-O-acetyl-β-D-glucopyranose (6a) [25] and 1,2,4,6-tetra-O-benzoyl-β-D-glucopyranose (6b)
[26] with yields of 93% and 86%, respectively (Scheme 1). A furanose-type precursor of [18F]3FDA, 3,
was prepared from 1,2:5,6-di-O-isopropylidene-α-D-glucofuranose (14) using a literature method [27]. In
contrast, pyranose-type precursors of [18F]6FDA, 5a and 5b, were prepared from D-allose (7) by a 4-step
reaction with overall yields of 52% and 21%, respectively (Scheme 2).

For identification of radioactive compounds [18F]3FDA, [18F]6FDA, [18F]11a, [18F]11b, [18F]12a,
and [18F]12b, non-radioactive authentic standards 3FDA, 6FDA, 11a, 11b, 12a, and 12b were also
synthesized (Scheme 3).
2.2
Manual operation synthesis
The 18F-labeling and hydrolytic deprotection procedure using manual operation synthesis is
shown in Scheme 4. The total synthesis time of manual operation was approximately 1–2 hours. The
RCCs using manual operation synthesis were determined by the ratio of photographic densities of
18F-labeled compound TLC spots. The RCCs of [18F]fluorination, RCCs of products [18F]3FDA or
[18F]6FDA, and calculated efficiencies of hydrolytic deprotection reactions (calculated by dividing the
RCCs of the product by those of [18F]fluorination) are summarized in Table 1.
18F-labeled intermediates [18F]13, [18F]11a, [18F]11b, [18F]12a, and [18F]12b were derived from
generated precursors, 3, 4a, 4b, 5a, and 5b with 9%, 88%, 85%, 90% and 88% RCC, respectively. This
means that pyranose type precursors 4a, 4b, 5a, and 5b had higher RCCs (85%–90%) than furanose-type
ones did, (3, 9%). Regarding the hydrolytic deprotection reactions of acyl groups by NaOH, acetyl
derivatives [18F]11a and [18F]12a proceeded to [18F]3FDA and [18F]6FDA with efficiencies of 85% and
77%, respectively. The hydrolytic deprotection efficiency of benzoyl derivatives, from [18F]11b to
[18F]3FDA and [18F]12b to [18F]6FDA, were 38% and 30%, respectively. The results showed that the

efficiencies of deprotection with acyl groups by NaOH were higher than those with benzoyl derivatives.
Acetyl groups were able to react with NaOH at room temperature in <5 min, while benzoyl groups
needed 30 min for the deprotection reaction to complete. As a whole, 4a and 5a were found to be practical
precursors for synthesis of [18F]3FDA and [18F]6FDA, respectively.
2.3
Automated synthesis
[18F]3FDA and [18F]6FDA were also synthesized from 4a and 5a using a commercially available
automated synthesizer. Results for the synthesis of [18F]3FDA and [18F]6FDA by using NaOH hydrolytic
deprotection with high performance liquid chromatography (HPLC) purification (method 1), NaOH
hydrolytic deprotection with solid phase extraction (SPE) (method 2), or HCl hydrolytic deprotection
with SPE purification (method 3) on the automated synthesizer are summarized in Table 2. The
radiochemical yields value of method 2 (decay corrected based on [18F]fluoride; 67% for [18F]3FDA and
49% for [18F]6FDA) was higher than that of method 1 (43% and 26%, respectively) or method 3 (44%
and 31%). The radiochemical purity of method 1 (>99.9% for [18F]3FDA and >99.9% for [18F]6FDA)
was somewhat higher than that of method 2 (98.6% and 99.0%, respectively) or method 3 (99.1% and
99.5%). Regarding total synthesis time, method 2 (41 min for [18F]3FDA and 41 min for [18F]6FDA) was
somewhat shorter than method 1 (52 min and 57 min, respectively) or method 3 (58 min and 44 min).
However, total synthesis time required for methods 1–3 was reasonably short considering the physical

half-life of 18F radionuclide.
2.4
Test of stability in blood plasma
No decomposition was observed in blood plasma for 6 h, suggesting that both [18F]3FDA and
[18F]6FDA were stable in blood plasma and meet the requirements for in vivo PET imaging.
3.
Conclusion
Suitable synthetic procedures for [18F]3FDA and [18F]6FDA have been established. Therefore,
[18F]3FDA and [18F]6FDA can allow assessment of the behavior of D-allose in organs in vivo using PET.
In addition, [18F]3FDA and [18F]6FDA were proven to be sufficiently stable in in vitro blood
plasma. This property is practically important to simplify analysis of PET imaging data.
In the course of the present study, we also established synthetic methods for precursors 4a and
5a.
Limitation: Possible limitations may include the inability to detect differences between D-allose
and D-allose analogs of [18F]3FDA and [18F]6FDA, This problem corresponds to a similar inability to
distinguish between D-glucose and D-glucose analogs of [18F]FDG. For example, it is reported that
[18F]FDG has different metabolic rates from D-glucose [28,29]. Differences of [18F]3FDA and [18F]6FDA

from D-allose could be clarified by the use of the natural substance and specific labeled D-allose by 11C
or 14C [30].
4.
Experimental
4.1
General methods
1,2:5,6-Di-O-isopropylidene-α-D-glucofuranose (14) was obtained from Kanto Chemicals Co.,
Inc. D-Allose (7) was obtained from Nagara Science Co., Ltd. 1,2,4,6-Tetra-O-acetyl-β-D-glucopyranose
(6a) [25] and 1,2,4,6-tetra-O-benzoyl-β-D-glucopyranose (6b) [26] were prepared from 14 by 4-step
reactions using the literature method [25].
1
13
1
Non-radioactive compounds were identified by 1D H and C NMR, 2D H-1H COSY using a
JNM-ECA600 (JEOL, Tokyo, Japan), and high-resolution FAB mass spectroscopy using a JMS-GCmate
II (JEOL, Tokyo, Japan) with sodium doping.
Heparinized rabbit blood (New Zealand White) was obtained from Rockland Immunochemicals,
Inc. (Limerick, PA, USA).
18
No-carrier-added [18F]fluoride was produced by proton irradiation of O-enriched water (Taiyo
Nippon Sanso, Tokyo, Japan) using an HM-18 cyclotron (Sumitomo Heavy Industries, Tokyo, Japan), a
BC168 Baby-cyclotron (The Japan Steel works, Ltd, Tokyo, Japan), and an HM-20 cyclotron (Sumitomo
Heavy Industries). A Hybrid-type Synthesizer (JFE Engineering Corporation) or F100 (Sumitomo Heavy

Industries) was used as the automated synthesizer. The RCCs were determined by silica gel TLC (Merck
18
0.2 mm 60F254 on aluminum sheet). The ratio of F-labeled compounds on TLC was determined by
recording the scanning values of exposed BAS IP MS 2040 E imaging plate (GE Healthcare Japan, Tokyo,
Japan) with an FLA-7000 imaging analyzer (Fujifilm, Tokyo, Japan).
4.2
1,2:5,6-di-O-isopropylidene-3-O-trifluoromethanesulfonyl-α-D-glucofuranose (3)
3 was prepared by a 1-step reaction using a literature method [27] as follows: 14 (1042 mg, 4
mmol) and pyridine (1249 µL, 15.5 mmol) were dissolved in CH2Cl2 (83 mL), and the mixture was
cooled to −17 °C. Trifluoromethanesulfonic anhydride (808 µL, 4.8 mmol) was added to the solution, and
the mixture was stirred for 4.5 h. The reaction mixture was poured to mixture of ice (20 g) and saturated
aqueous NaHCO3 (20 mL), and the mixture was extracted with CH2Cl2 (50 mL×2). The combined
organic layer was dried over Na2SO4, and the mixture was filtered. The filtrate was concentrated under
reduced pressure at <37 °C, and pyridine was azeotropically removed by toluene (100 mL×3). The
residue was dissolved in hexane (160 mL), and supernatant was filtered. The filtrate was concentrated
under reduced pressure at <37 °C, 3 (1548 mg, 99%) was obtained: colorless powder; mp 70 °C (dec.,
1
from hexane; lit. 70.0 °C from light petroleum [27]); H NMR (600 MHz, CDCl3): δ 5.99 (d, 1H, J=4.1
Hz, H-1), 5.26 (d, 1H, J=2.1 Hz, H-3), 4.77 (d, 1H, J=4.1 Hz, H-2), 4.23-4.18 (m, 2H, H-4 and H-5), 4.15
(dd, 1H, J=8.9, 5.5 Hz, H-6a), 3.97 (dd, 1H, J=8.9, 4.1 Hz, H-6b), 1.52 (s, 3H, Me), 1.43 (s, 3H, Me),

1.34 (s, 3H, Me), 1.33 (s, 3H, Me).
4.3
1,2,4,6-Tetra-O-acetyl-3-O-trifluoromethanesulfonyl-β-D-glucopyranose (4a)
6a (699 mg, 2 mmol) and pyridine (645 µL, 8 mmol) were dissolved in CH2Cl2 (40 mL), and the
mixture was cooled to −17 °C. Trifluoromethanesulfonic anhydride (673 µL, 4 mmol) was added to the
solution, and the mixture was heated to room temperature (rt) and stirred for 30 min. After cooling to
−17 °C, water (40 mL) was added to the reaction mixture, and the mixture was extracted with CH2Cl2 (40
mL×3). The combined organic layer was dried over Na2SO4, and the mixture was filtered. The filtrate was
concentrated under reduced pressure, and pyridine was azeotropically removed by toluene (100 mL×3).
The residue was separated by silica gel (48 g) flash column chromatography (eluent: hexane/AcOEt=3:1),
and the separated fraction was concentrated under reduced pressure. After the residue was recrystallized
from AcOEt (5 mL)-hexane (45 mL), 4a (896 mg, 93%) was obtained: colorless needles; mp 87–88 °C
1
(dec., from AcOEt-hexane); H NMR (600 MHz, CDCl3): δ 5.71 (d, 1H, J=8.3 Hz, H-1), 5.323 (t, 1H,
J=9.7 Hz, H-4), 5.318 (dd, 1H, J=9.7, 8.3 Hz, H-2), 5.05 (t, 1H, J=9.7 Hz, H-3), 4.28 (dd, 1H, J=12.6, 4.3
Hz, H-6a), 4.13 (dd, 1H, J=12.6, 2.3 Hz, H-6b), 3.82 (ddd, 1H, J=9.7, 4.3, 2.3 Hz, H-5), 2.13 (s, 3H, Ac),
13
2.12 (s, 3H, Ac), 2.11 (s, 3H, Ac), 2.10 (s, 3H, Ac); C NMR (150 MHz, CDCl3): δ 170.53, 168.94,
168.76, 168.68, 118.23 (q, J=319.3 Hz), 91.44, 84.07, 72.52, 69.15, 66.83, 61.11, 20.71, 20.67, 20.39,
20.33; HRMS (FAB): calculated 503.0447 for C15H19O12F3S [M+Na]+, found 503.0442; IR (KBr, cm-1):

1755, 1210.
4.4
1,2,4,6-Tetra-O-benzoyl-3-O-trifluoromethanesulfonyl-β-D-glucopyranose (4b)
6b (596 mg, 1 mmol) and pyridine (193 µL, 2.4 mmol) were dissolved in CH2Cl2 (3 mL) and
cooled to −17 °C. Trifluoromethanesulfonic anhydride (202 µL, 1.2 mmol) was added to the solution, and
trhen the mixture was heated to rt and stirred for 1 h. After cooling to −17 °C, saturated aqueous NaHCO3
(10 mL) was added to the reaction mixture, and the mixture was extracted with CH2Cl2 (20 mL×3). The
combined organic layer was washed with water (10 mL) and dried over Na2SO4. The mixture was then
filtered, and the filtrate was concentrated under reduced pressure, after which the pyridine was
azeotropically removed by toluene (20 mL×4). The residue was recrystallized from i-PrOH (20 mL),
yielding 4b (626 mg, 86%): colorless powder; mp 130–131 °C (dec., from i-PrOH); 1H NMR (600 MHz,
CDCl3): δ 8.06–7.99 (m, 8H, Ph), 7.59 (t, 1H, J=7.6 Hz, Ph), 7.57–7.51 (m, 3H, Ph), 7.46–7.37 (m, 8H,
Ph), 6.20 (d, 1H, J=8.2 Hz, H-1), 5.92 (dd, 1H, J=9.6, 8.2 Hz, H-2), 5.88 (t, 1H, J=9.6 Hz, H-4), 5.54 (t,
1H, J=9.6 Hz, H-3), 4.65 (dd, 1H, J=12.4, 3.5 Hz, H-6a), 4.46 (dd, 1H, J=12.4, 4.8 Hz, H-6b), 4.31 (ddd,
13
1H, J=9.6, 4.8, 3.5 Hz, H-5); C NMR (150 MHz, CDCl3): δ 165.99, 164.64 (2C), 164.39, 134.08,
133.97, 133.85, 133.22, 130.25 (2C), 130.08 (2C), 129.99 (2C), 129.82 (2C), 129.32, 128.61 (4C), 128.55
(2C), 128.39 (2C), 128.21, 128.18, 128.04, 118.06 (q, JF=320.8 Hz), 92.31, 84.06, 72.74, 69.85, 68.22,
62.25; HRMS (FAB): calculated 751.1073 for C35H27O12F3S [M+Na]+, found 751.1063; IR (KBr, cm-1):

1737, 1267.
4.5
1,2,3,4-Tetra-O-acetyl-6-O-triphenylmethyl-β-D-allopyranose (9a)
Triphenylmethyl chloride (15.336 g, 55 mmol) was added to D-allose (7) (9.021 g, 50 mmol),
which was suspended in pyridine (100 mL), the mixture was stirred at 40 °C for 5 days. The reaction
mixture was cooled to rt, and acetic anhydride (37.8 mL, 400 mmol) was added, after which the mixture
was stirred at rt for 6 days. The reaction mixture was cooled to 0 °C, and water (100 mL) was added to
the mixture, which was extracted with CHCl3 (100 mL×3). The combined organic layer was dried over
Na2SO4, and the mixture was filtered. The filtrate was concentrated under reduced pressure, and the
pyridine was azeotropically removed by toluene (100 mL×4). The residue was separated by silica gel (50
g) column chromatography (eluent: CH2Cl2/AcOEt=9:1), and the separated fraction was concentrated
under reduced pressure. After the residue was recrystallized from toluene, 9a (18.426 g, 62%) was
obtained: colorless prisms; mp 216–217 °C (from toluene); 1H NMR (600 MHz, CDCl3): δ 7.43 (dd, 6H,
J=7.8, 1.3 Hz, Ph), 7.28 (t, 6H, J=7.8 Hz, Ph), 7.22 (dt, 3H, J=7.8, 1.3 Hz, Ph), 6.01 (d, 1H, J=8.6 Hz,
H-1), 5.71 (t, 1H, J=2.9 Hz, H-3), 5.23 (dd, 1H, J=10.2, 2.9 Hz, H-4), 5.08 (dd, 1H, J=8.6, 2.9 Hz, H-2),
4.06 (ddd, 1H, J=10.2, 3.7, 2.2 Hz, H-5), 3.39 (dd, 1H, J=10.6, 2.2 Hz, H-6a), 3.03 (dd, 1H, J=10.6, 3.7
13
Hz, H-6b), 2.16 (s, 3H, Ac), 2.11 (s, 3H, Ac), 2.03 (s, 3H, Ac), 1.75 (s, 3H, Ac); C NMR (150 MHz,
CDCl3): δ 169.87, 169.33, 169.12, 168.76, 143.58 (3C), 128.70 (6C), 127.79 (6C), 127.01 (3C), 90.36,

86.42, 72.36, 68.49, 68.32, 66.04, 61.54; HRMS (FAB): calculated 613.2050 for C33H34O10 [M+Na]+,
found 613.2040; IR (KBr, cm-1): 1757, 1221.
4.6
1,2,3,4-Tetra-O-acetyl-β-D-allopyranose (10a)
10% Pd/C (21.291 g) was suspended in 1,2-dichloroethane (360 mL), and 9a (11.813 g, 20
mmol) was solved to the suspension. Then, 98% formic acid (40 mL) was added, and the mixture was
stirred at rt for 3 h. Then, the reaction mixture was filtered by Celite and washed with CHCl3. The
combined filtrate was concentrated under reduced pressure, and the formic acid was azeotropically
removed by toluene (40 mL×3). The residue was separated by silica gel (118.1 g) column
chromatography (eluent: hexane/AcOEt=1:2), and after the separated fraction was concentrated under
1
reduced pressure, 10a (6.713 g, 96%) was obtained: colorless prisms; mp 122–123 °C (from MeOH); H
NMR (600 MHz, CDCl3): δ 6.02 (d, 1H, J=8.6 Hz, H-1), 5.73 (t, 1H, J=3.0 Hz, H-3), 5.03 (dd, 1H,
J=10.3, 3.0 Hz, H-4), 4.97 (dd, 1H, J=8.6, 3.0 Hz, H-2), 4.06 (ddd, 1H, J=10.3, 4.3, 2.3 Hz, H-5), 3.79
(ddd, 1H, J=12.6, 6.9, 2.3 Hz, H-6a), 3.59 (ddd, 1H, J=12.6. 6.9, 4.3 Hz, H-6b), 2.19 (t, 1H, J=6.9 Hz,
OH), 2.17 (s, 3H, Ac), 2.13 (s, 3H, Ac), 2.04 (s, 3H, Ac), 2.02 (s, 3H, Ac); 13C NMR (150 MHz, CDCl3):
δ 169.88, 169.61, 169.41, 169.09, 90.10, 73.29, 68.45, 68.29, 65.77, 61.00, 20.93, 20.70, 20.60, 20.54;
HRMS (FAB): calculated 317.0954 for C14H20O10 [M+Na]+, found 371.0949; IR (KBr, cm-1): 3589, 3507,
1750, 1225.

4.7
1,2,3,4-Tetra-O-acetyl-6-O-trifluoromethanesulfonyl-β-D-allopyranose (5a)
10a (349 mg, 1 mmol) and 2,6-lutidine (463 µL, 4 mmol) were dissolved in CH2Cl2 (20 mL), and
the mixture was cooled to 0 °C. Trifluoromethanesulfonic anhydride (337 µL, 2 mmol) was added to the
solution, and the mixture was stirred at 0 °C for 1 h. Water (20 mL) was added to the reaction mixture,
and the mixture was extracted with CH2Cl2 (20 mL×3). The combined organic layer was dried over
Na2SO4, and the mixture was filtered. The filtrate was concentrated under reduced pressure, and the
2,6-lutidine was azeotropically removed by toluene (50 mL×4). The residue was separated by silica gel
(24 g) flash column chromatography (eluent: hexane/AcOEt=2:1), and the separated fraction was
concentrated under reduced pressure. After the residue was recrystallized from AcOEt (0.8 mL)-hexane
(7.2 mL), 5a (419 mg, 87%) was obtained: colorless needles; mp 81–82 °C (dec., from AcOEt-hexane);
1H NMR (600 MHz, CDCl3): δ 6.02 (d, 1H, J=8.6 Hz, H-1), 5.76 (t, 1H, J=2.9 Hz, H-3), 5.00 (dd, 1H,
J=8.6, 2.9 Hz, H-2), 4.96 (dd, 1H, J=10.3, 2.9 Hz, H-4), 4.59 (dd, 1H, J=11.2, 2.3 Hz, H-6a), 4.55 (dd, 1H,
J=11.2, 4.4 Hz, H-6b), 4.31 (ddd, 1H, J=10.3, 4.4, 2.3 Hz, H-5), 2.18 (s, 3H, Ac), 2.13 (s, 3H, Ac), 2.04 (s,
13
3H, Ac), 2.03 (s, 3H, Ac); C NMR (150 MHz, CDCl3): δ 169.64, 169.14, 168.89, 168.85, 118.41 (q,
JF=319.3 Hz), 89.88, 73.21, 70.23, 67.89, 67.77, 65.72, 20.79, 20.63, 20.48, 20.38; HRMS (FAB):
calculated for 503.0447 C15H19O12F3S [M+Na]+, found 503.0442; IR (KBr, cm-1): 1755, 1744, 1245,
1212.

4.8
1,2,3,4-Tetra-O-benzoyl-β-D-allopyranose (10b)
Triphenylmethyl chloride (1 g, 3.6 mmol) and CHCl3 (6 mL) were added to 7 (540 mg, 3 mmol),
which was suspended in pyridine (3 mL), and mixture was stirred at 40 °C for 3 days. The reaction
mixture was cooled to rt, and benzoyl chloride (2.2 mL, 19 mmol) was added. The mixture was stirred at
rt for 1 h and then cooled to 0 °C, after which ice (10 g) and iced water (20 mL) were added to the
mixture. Then, the mixture was extracted with CHCl3 (15 mL×3). The combined organic layer was
washed with water (15 mL×2) and saturated aqueous NaHCO3 (15 mL×1). The resulting organic layer
was then dried over Na2SO4, and then the mixture was filtered. The filtrate was concentrated under
reduced pressure, and the pyridine was azeotropically removed by toluene (50 mL×2). The residue was
dissolved in dichloromethane (30 mL), and FeCl3·6H2O (1.6 g, 6 mmol) was added to the mixture, after
which the mixture was stirred at rt for 1 day. Water (40 mL) and CHCl3 (10 mL) were added to the
reaction mixture, and the organic layer was separated and extracted with CHCl3 (20 mL×2). The
combined organic layer was washed with saturated aqueous NaHCO3 (20 mL×1), and the resulting
organic layer was dried over Na2SO4. The mixture was filtered, and the filtrate was concentrated under
reduced pressure. The residue was separated by silica gel (90 g) column chromatography (eluent:
hexane/AcOEt=3:1), and the separated fraction was concentrated under reduced pressure. After the
residue was recrystallized from MeOH, 10b (395 mg, 22%) was obtained: colorless prisms; mp 181–

182 °C (from MeOH); 1H NMR (600 MHz, CDCl3): δ 8.10 (d, 2H, J=7.6 Hz, Ph), 8.05 (d, 2H, J=7.6 Hz,
Ph), 7.88 (d, 2H, J=7.6 Hz, Ph), 7.84 (d, 2H, J=7.6 Hz, Ph), 7.67 (t, 1H, J=7.6 Hz, Ph), 7.57–7.50 (m, 4H,
Ph), 7.46 (t, 1H, J=7.6 Hz, Ph), 7.42 (t, 2H, J=7.6 Hz, Ph), 7.35 (t, 2H, J=7.6 Hz, Ph), 7.28 (t, 2H, J=7.6
Hz, Ph), 6.61 (d, 1H, J=8.9 Hz, H-1), 6.33 (t, 1H, J=2.8 Hz, H-3), 5.70 (dd, 1H, J=8.9, 2.8 Hz, H-2), 5.56
(dd, 1H, J=9.6, 2.8 Hz, H-4), 4.51 (ddd, 1H, J=9.6, 4.8, 2.1 Hz, H-5), 3.95 (ddd, 1H, J=12.4, 5.5, 2.1 Hz,
13
H-6a), 3.76 (ddd, 1H, J=12.4, 5.5, 4.8 Hz, H-6b), 2.50 (t, 1H, J=5.5 Hz, OH); C NMR (150 MHz,
CDCl3): δ 165.34 (2C), 165.10, 164.82, 133.91, 133.70, 133.66, 133.45, 130.15 (2C), 129.87 (2C), 129.81
(4C), 129.29, 128.79 (3C), 128.72, 128.57 (2C), 128.54, 128.49 (2C), 128.40 (2C), 91.35, 74.12, 69.48,
68.91, 66.68, 61.25; HRMS (FAB): calculated 619.1580 for C34H28O10 [M+Na]+, found 619.1572; IR
(KBr, cm-1): 3491, 1733, 1267.
4.9
1,2,3,4-Tetra-O-benzoyl-6-O-trifluoromethanesulfonyl-β-D-allopyranose (5b)
10b (1194 mg, 2 mmol) and 2,6-lutidine (927 µL, 8 mmol) were dissolved in CH2Cl2 (40 mL),
and the mixture was cooled to 0 °C. Trifluoromethanesulfonic anhydride (673 µL, 4 mmol) was added to
the solution and stirred at 0 °C for 1 h. Water (40 mL) was added to the reaction mixture, and the mixture
was extracted with CH2Cl2 (40 mL×3). The combined organic layer was dried over Na2SO4, and the
mixture was filtered. The filtrate was concentrated under reduced pressure, and the 2,6-lutidine was
azeotropically removed by toluene (100 mL×4). The residue was separated by silica gel (72.9 g) flash

column chromatography (eluent: CH2Cl2), and the separated fraction was concentrated under reduced
pressure. After the residue was recrystallized from CH2Cl2 (4 mL)-hexane (16 mL), 5b (1398 mg, 96%)
1
was obtained: colorless powder; mp 102–104 °C (dec., from CH2Cl2-hexane); H NMR (600 MHz,
CDCl3): δ 8.07 (dd, 2H, J=8.3, 1.2 Hz, Ph), 8.05 (dd, 2H, J=8.3, 1.2 Hz, Ph), 7.87 (dd, 2H, J=8.3, 1.2 Hz,
Ph), 7.84 (dd, 2H, J=8.3, 1.2 Hz, Ph), 7.67, (tt, 1H, J=7.5, 1.2 Hz, Ph), 7.59–7.52 (m, 4H, Ph), 7.46 (tt, 1H,
J=7.5, 1.2 Hz, Ph), 7.44 (dd, 2H, J=8.3, 7.5 Hz, Ph), 7.37 (dd, 2H, J=8.3, 7.5 Hz, Ph), 7.28 (dd, 2H, J=8.3,
7.5 Hz, Ph), 6.63 (d, 1H, J=8.5 Hz, H-1), 6.36 (t, 1H, J=3.0 Hz, H-3), 5.72 (dd, 1H, J=8.5, 3.0 Hz, H-2),
5.51 (dd, 1H, J=10.3, 3.0 Hz, H-4), 4.76 (ddd, 1H, J=10.3, 5.1, 2.3 Hz, H-5), 4.75 (dd, 1H, J=11.4, 2.3 Hz,
13
H-6a), 4.69 (dd, 1H, J=11.4, 5.1 Hz, H-6b); C NMR (150 MHz, CDCl3): δ 165.14, 164.81, 164.66,
164.63, 134.00, 133.86, 133.83, 133.54, 130.17 (2C), 129.82 (4C), 129.80 (2C), 129.02, 128.86 (2C),
128.65, 128.62 (2C), 128.57 (2C), 128.42 (2C), 128.38 (2C), 118.50 (q, JF=320.1 Hz), 91.04, 73.34, 71.05,
68.90, 68.48, 66.46; HRMS (FAB): calculated 751.1073 for C35H27O12F3S [M+Na]+, found 751.1063; IR
(KBr, cm-1): 1731, 1261.
4.10
1,2,4,6-Tetra-O-acetyl-3-deoxy-3-fluoro-β-D-allopyranose (11a)
6a (697 mg, 2 mmol) was dissolved in CH2Cl2 (6 mL) and cooled to −17 °C, and then
(diethylamino)sulfur trifluoride (1585 µL, 12 mmol) was added to the solution at −17 °C. The mixture
was heated to rt and stirred for 14 days. The reaction mixture was cooled to −17 °C again, and saturated

aqueous NaHCO3 (10 mL) was added to the mixture. The mixture was heated to rt and stirred for 2 h. The
reaction mixture was extracted with CHCl3 (30 mL×3), and the combined organic layer was dried over
Na2SO4. The mixture was filtered, and the filtrate was concentrated under reduced pressure. The residue
was separated by silica gel (35 g) column chromatography (eluent: hexane/AcOEt=1:1), and after the
separated fraction was concentrated under reduced pressure, 11a (106 mg, 15%) was obtained: colorless
prisms; mp 86–87 °C (from MeOH); 1H NMR (600 MHz, CDCl3): δ 6.02 (d, 1H, J=8.6 Hz, H-1), 5.15 (dt,
1H, JF=53.6 Hz, J=2.1 Hz, H-3), 4.94 (ddd, 1H, JF=27.0 Hz, J=10.2, 2.1 Hz, H-4), 4.93 (ddd, 1H, JF=27.4
Hz, J=8.6, 2.1 Hz, H-2), 4.33 (dd, 1H, J=12.4, 4.1 Hz, H-6a), 4.23 (ddd, 1H, J=10.2, 4.1, 1.9 Hz, H-5),
4.18 (dd, 1H, J=12.4, 1.9 Hz, H-6b), 2.133 (s, 3H, Ac), 2.128 (s, 3H, Ac), 2.121 (s, 3H, Ac), 2.09 (s, 3H,
13
Ac); C NMR (150 MHz, CDCl3): δ 170.65, 169.45, 169.38, 168.99, 89.73 (d, JF=4.3 Hz), 87.58 (d,
JF=183.5 Hz), 70.39 (d, JF=2.9 Hz), 68.99 (d, JF=17.3 Hz), 66.40 (d, JF=17.4 Hz), 61.71, 20.88, 20.74,
20.63 (2C); HRMS (FAB): calculated 373.0911 for C14H19O9F [M+Na]+, found 373.0906; IR (KBr, cm-1):
1764, 1747, 1737, 1243, 1234, 1209.
4.11
1,2,4,6-Tetra-O-benzoyl-3-deoxy-3-fluoro-β-D-allopyranose (11b)
6b (596 mg, 1 mmol) was dissolved in CH2Cl2 (3 mL) and cooled to −17 °C, and
(diethylamino)sulfur trifluoride (528 µL, 4 mmol) was added to the solution at −17 °C. The mixture was
heated to rt and stirred for 9 days. Then, the reaction mixture was cooled to −17 °C again, and saturated

aqueous NaHCO3 (10 mL) was added. The resulting mixture was heated to rt and stirred for 2 h. The
reaction mixture was then extracted with CHCl3 (20 mL×3), and the combined organic layer was dried
over Na2SO4. The mixture was filtered, and the filtrate was concentrated under reduced pressure. The
residue was separated by silica gel (18 g) column chromatography (eluent: hexane/AcOEt=9:1), and after
the separated fraction was concentrated under reduced pressure, 11b (304 mg, 51%) was obtained:
colorless powder; mp 151–152 °C (from MeOH); 1H NMR (600 MHz, CDCl3): δ 8.10–8.00 (m, 8H, Ph),
7.59 (t, 1H, J=7.6 Hz, Ph), 7.57–7.52 (m, 3H, Ph), 7.46–7.38 (m, 8H, Ph), 6.55 (d, 1H, J=8.2 Hz, H-1),
5.55 (ddd, 1H, JF=27.5 Hz, J=8.2, 2.1 Hz, H-2), 5.51 (dt, 1H, JF=51.5 Hz, J=2.1 Hz, H-3), 5.48 (ddd, 1H,
JF=28.8 Hz, J=10.3, 2.1 Hz, H-4), 4.74–4.68 (m, 2H, H-5 and H-6a), 4.52 (dd, 1H, J=12.4, 4.8 Hz, H-6b);
13C NMR (150 MHz, CDCl3): δ 166.09, 165.08, 165.01, 164.67, 133.78 (2C), 133.68, 133.15, 130.13
(2C), 129.97 (4C), 129.79 (2C), 129.52, 128.72, 128.69, 128.57 (2C), 128.51 (3C), 128.48 (2C), 128.37
(2C), 90.67 (d, JF=2.9 Hz), 88.04 (d, JF=185.0 Hz), 70.75 (d, JF=2.9 Hz), 69.50 (d, JF=15.9 Hz), 67.66 (d,
JF=17.3 Hz), 62.82; HRMS (FAB): calculated 621.1537 for C34H27O9F [M+Na]+, found 621.1530; IR
(KBr, cm-1): 1728, 1272.
4.12
3-Deoxy-3-fluoro-D-allose (3FDA: 1)
11b (121 mg, 0.2 mmol) was dissolved in 1,4-dioxane (20 mL), and 0.2 mol/L aqueous NaOH
(10 mL) was added to the solution. The mixture was stirred at rt for 2 h, and then 0.2 mol/L aqueous HCl

(12 mL) was added. The resulting mixture was concentrated under reduced pressure, and then 3FDA (27
mg, 75%) was separated by preparative HPLC (Column: Nakarai Cosmosil Sugar-D, 20 mmI.D.×20+250
mm, eluent: CH3CN/H2O=3:1, flow rate: 10 mL/min) with RI-2031 refractive index detector (JASCO,
Tokyo, Japan).
1
β-Pyranose form (ca. 90% equilibrium ratio in D2O) of 3FDA (3-deoxy-3-fluoro-β-D-allopyranose): H
NMR (600 MHz, D2O): δ 4.87 (dt, 1H, JF=53.5 Hz, J=2.1 Hz, H-3), 4.77 (d, 1H, J=8.3 Hz, H-1), 3.74 (dd,
1H, J=12.3, 2.0 Hz, H-6a), 3.66 (ddd, 1H, J=10.1, 5.4, 2.0 Hz, H-5), 3.60 (ddd, 1H, JF=29.1 Hz, J=10.1,
13
2.1 Hz, H-4), 3.57 (dd, 1H, J=12.3, 5.4 Hz, H-6b), 3.37 (ddd, 1H, JF=30.1 Hz, J=8.3, 2.1 Hz, H-2); C
NMR (150 MHz, D2O): δ 93.58, 93.38 (d, JF=173.4 Hz), 73.74, 70.39 (d, JF=15.8 Hz), 65.86 (d, JF=17.4
Hz), 60.82.
1
α-Pyranose form (ca. 10% equilibrium ratio in D2O) of 3FDA (3-deoxy-3-fluoro-α-D-allopyranose): H
NMR (600 MHz, D2O): δ 5.08 (d, 1H, J=4.4 Hz, H-1), 4.85 (dt, 1H, JF=54.4 Hz, J=2.4 Hz, H-3), 3.86
(ddd, 1H, J=10.5, 5.0, 2.2 Hz, H-5), 3.73 (dd, 1H, J=12.2, 5.0 Hz, H-6a), 3.68 (dd, 1H, J=12.2, 2.2 Hz,
H-6b), 3.67 (ddd, 1H, JF=28.1 Hz, J=4.4, 2.4 Hz, H-2), 3.67–3.56 (m, overlapped with peak of
β-pyranose form according to 1H-1H COSY, H-4); 13C NMR (150 MHz, D2O): δ 92.59 (d, JF=176.3 Hz),
91.29, 66.723 (d, JF=15.9 Hz), 66.718, 65.12 (d, JF=18.8 Hz), 60.49.
HRMS (FAB): calculated 205.0488 for C6H11O5F [M+Na]+, found 205.0484.

4.13
1,2,3,4-Tetra-O-acetyl-6-deoxy-6-fluoro-β-D-allopyranose (12a)
10a (2.704 g, 7.75 mmol) was dissolved in CH2Cl2 (23.3 mL) and cooled to −17 °C, and
(diethylamino)sulfur trifluoride (5 g, 31 mmol) was added to the solution at −17 °C. The mixture was
heated to rt and stirred for 20 h. The reaction mixture was cooled to −17 °C again, and saturated aqueous
NaHCO3 (100 mL) was added. The resulting mixture was heated to rt and stirred for 1 h. The reaction
mixture was then extracted with CHCl3 (50 mL×3), and the combined organic layer was dried over
Na2SO4. The mixture was filtered, and the filtrate was concentrated under reduced pressure. The residue
was separated by silica gel (135.8 g) column chromatography (eluent: hexane/AcOEt=1:2), and after the
separated fraction was concentrated under reduced pressure, 12a (574 mg, 21%) was obtained: colorless
prisms; mp 119–120 °C (from MeOH); 1H NMR (600 MHz, CDCl3): δ 6.02 (d, 1H, J=8.6 Hz, H-1), 5.75
(t, 1H, J=2.9 Hz, H-3), 5.04 (dd, 1H, J=10.3, 2.9 Hz, H-4), 5.00 (dd, 1H, J=8.6, 2.9 Hz, H-2), 4.56 (ddd,
1H, JF=47.5 Hz, J=10.6, 2.0 Hz, H-6a), 4.47 (ddd, 1H, JF=46.9 Hz, J=10.6, 3.6 Hz, H-6b), 4.19 (dddd, 1H,
JF=24.9 Hz, J=10.3, 3.6, 2.0 Hz, H-5), 2.17 (s, 3H, Ac), 2.13 (s, 3H, Ac), 2.03 (s, 3H, Ac), 2.02 (s, 3H,
13
Ac); C NMR (150 MHz, CDCl3): δ 169.79, 169.32, 168.99, 168.95, 90.00, 80.93 (d, JF=174.9 Hz),
71.72 (d, JF=18.8 Hz), 68.16, 68.02, 65.30 (d, JF=7.3 Hz), 20.90, 20.66, 20.51 (2C); HRMS (FAB):
calculated 373.0911 for C14H19O9F [M+Na]+, found 373.0906; IR (KBr, cm-1): 1755, 1222.
4.14
1,2,3,4-Tetra-O-benzoyl-6-deoxy-6-fluoro-β-D-allopyranose (12b)

10b (418 mg, 0.7 mmol) was dissolved in CH2Cl2 (1.4 mL) and cooled to −17 °C, and
(diethylamino) sulfur trifluoride (370 µL, 2.8 mmol) was added to the solution at −17 °C. The mixture
was heated to rt and stirred for 1 day. The reaction mixture was then cooled to −17 °C again, and
saturated aqueous NaHCO3 (10 mL) was added. The resulting mixture was heated to rt and stirred for 2 h.
The reaction mixture was then extracted with CHCl3 (20 mL×3), and the combined organic layer was
dried over Na2SO4. The mixture was filtered, and the filtrate was concentrated under reduced pressure.
The residue was separated by silica gel (21 g) column chromatography (eluent: hexane/AcOEt=9:1), and
after the separated fraction was concentrated under reduced pressure, 12b (137 mg, 33%) was obtained:
1
colorless powder; mp 119–120 °C (from MeOH); H NMR (600 MHz, CDCl3): δ 8.07 (d, 2H, J=7.6 Hz,
Ph), 8.06 (d, 2H, J=7.6 Hz, Ph), 7.89 (d, 2H, J=7.6 Hz, Ph), 7.84 (d, 2H, J=7.6 Hz, Ph), 7.66 (t, 1H, J=7.6
Hz, Ph), 7.58–7.51 (m, 4H, Ph), 7.46 (t, 1H, J=7.6 Hz, Ph), 7.43 (t, 2H, J=7.6 Hz, Ph), 7.36 (t, 2H, J=7.6
Hz, Ph), 7.28 (t, 2H, J=7.6 Hz, Ph), 6.63 (d, 1H, J=8.3 Hz, H-1), 6.35 (t, 1H, J=2.8 Hz, H-3), 5.73 (dd, 1H,
J=8.3, 2.8 Hz, H-2), 5.58 (dd, 1H, J=10.3, 2.8 Hz, H-4), 4.710 (dd, 1H, JF=47.4 Hz, J=4.1 Hz, H-6a),
13
4.707 (dd, 1H, JF=49.4 Hz, J=2.1 Hz, H-6b), 4.60 (dddd, 1H, JF=21.3 Hz, J=10.3, 4.1, 2.1 Hz, H-5); C
NMR (150 MHz, CDCl3): δ 165.21, 164.99, 164.72, 164.67, 133.90, 133.71, 133.60, 133.45, 130.19 (2C),
129.80 (6C), 129.22, 128.78 (4C), 128.55 (2C), 128.52, 128.48 (2C), 128.40 (2C), 91.23, 81.13 (d,
JF=176.3 Hz), 72.51 (d, JF=18.8 Hz), 69.15, 68.65, 66.10 (d, JF=7.2 Hz); HRMS (FAB) calculated
621.1537 for C34H27O9F [M+Na]+, found 621.1529; IR (KBr, cm-1): 1734, 1263.

4.15
6-Deoxy-6-fluoro-D-allose (6FDA: 2)
12b (60 mg, 0.1 mmol) was dissolved in 1,4-dioxane (2.6 mL), and then 0.6 mol/L aqueous
NaOH (1 mL) was added to the solution. The mixture was stirred at rt for 1.5 h, and then 1 mol/L aqueous.
CH3CO2H (1.2 mL) was added to the reaction mixture. The mixture was concentrated under reduced
pressure, after which the CH3CO2H was azeotropically removed by water (5 mL×2). The resulting residue
was dissolved in water (5 mL), and the mixture was filtered by a syringe filter (pore size: 0.45 µm). The
filtrate was concentrated under reduced pressure, and 6FDA (7.7 mg, 42%) was purified by preparative
HPLC (Column: Nakarai Cosmosil 5C18-PAQ, 20 mmI.D.×50+250 mm, eluent: CH3CN/H2O=3:1, flow
rate: 10 mL/min) with an RI-2031 refractive index detector (JASCO, Tokyo, Japan).
1
β-Pyranose form (ca. 83% equilibrium ratio in D2O) of 6FDA (6-deoxy-6-fluoro-β-D-allopyranose): H
NMR (600 MHz, D2O): δ 4.81 (d, 1H, J=8.2 Hz, H-1), 4.60 (ddd, 1H, JF=47.5 Hz, J=11.0, 2.0 Hz, H-6a),
4.56 (ddd, 1H, JF=47.5 Hz, J=11.0, 4.1 Hz, H-6b), 4.09 (t, 1H, J=2.8 Hz, H-3), 3.64 (dd, 1H, J=10.3, 2.8
13
Hz, H-4), 3.82 (dddd, 1H, JF=27.5 Hz, J=10.3, 4.1, 2.0 Hz, H-5), 3.32 (dd, 1H, J=8.2, 2.8 Hz, H-2); C
NMR (150 MHz, D2O): δ 93.65, 82.89 (d, JF=167.6 Hz), 72.25 (d, JF=17.3 Hz), 71.17, 71.07, 65.75 (d,
JF=5.8).
1
α-Pyranose form (ca. 17% equilibrium ratio in D2O) of 6FDA (6-deoxy-6-fluoro-α-D-allopyranose): H
NMR (600 MHz, D2O): δ 5.06 (d, 1H, J=4.1 Hz, H-1), 4.60 (ddd, 1H, JF=47.5 Hz, J=11.0, 2.0 Hz, H-6a),

4.56 (ddd, 1H, JF=47.5 Hz, J=11.0, 4.1Hz, H-6b), 4.09 (t, 1H, J=2.8 Hz, H-3), 4.00 (dddd, 1H, JF=21.3
Hz, J=10.3, 4.1, 2.0 Hz, H-5), 3.64 (dd, 1H, J=10.3, 2.8 Hz, H-4), 3.61 (t, 1H, J=2.8 Hz, H-2); 13C NMR
(150 MHz, D2O): δ 93.06, 82.89 (d, JF=167.6 Hz), 71.61, 66.97, 65.93 (d, JF=17.3 Hz), 65.19 (d, JF=5.8
Hz).
HRMS (FAB): calculated 205.0488 for C6H11O5F [M+Na]+, found 205.0485.
4.16
General procedures for synthesis of 3-deoxy-3-[18F]fluoro-D-allose ([18F]3FDA: [18F]1) and
6-deoxy-6-[18F]fluoro-D-allose ([18F]6FDA: [18F]2) from 4a and 5a, respectively, by manual operation
synthesis
In total, 50–60 MBq of no-carrier-added [18F]fluoride in water (ca. 1 mL) was adsorbed to a
Waters Sep-Pak Accell Plus QMA Plus Light Cartridge, which was activated by 1 mol/L aqueous K2CO3
(10 mL) and water (30 mL). The [18F]fluoride was desorbed by a mixture of K2CO3 (17 µmol), cryptand
222 (34 µmol), water (0.2 mL), and CH3CN (0.7 mL). The eluent was concentrated by heating to 85 °C
with N2 flowing. CH3CN (1 mL) was added to the residue and azeotropically dried by heating to 85 °C
with N2 flowing. A CH3CN (1 mL) solution of 4a (20 mg, 42 µmol) or 5a (20 mg, 42 µmol) was added to
the
residue
and
stirred
at
85
°C
for
5
min,
and
or
1,2,4,6-tetra-O-acetyl-3-deoxy-3-[18F]fluoro-β-D-allopyranose
([18F]11a)
1,2,3,4-tetra-O-acetyl-6-deoxy-6-[18F]fluoro-β-D-allopyranose ([18F]12a) was obtained at 88% or 90%

RCC, respectively, determined by silica gel TLC (Rf 0.60 for [18F]11a, 0.58 for [18F]12a, eluent:
hexane/AcOEt=1:1), determined using authentic non-radioactive samples of 11a or 12a. After
concentration by heating to 85 °C with N2 flowing and cooling to rt, the residue was dissolved in
tetrahydrofuran (1 mL), and then 0.3 mol/L aqueous NaOH (1 mL) was added to the solution, the mixture
was shaken, and it stood at rt for 5 min. Then 1 mol/L aqueous CH3CO2H (0.5 mL) was added to the
reaction mixture, and [18F]3FDA or [18F]6FDA was obtained at 75% or 69% RCC, respectively, as
determined by silica gel TLC (Rf 0.38 for [18F]3FDA, 0.38 for [18F]6FDA, eluent: CHCl3/MeOH=2:1)
using authentic non-radioactive samples of 3FDA or 6FDA. After concentration by heating to 85 °C with
N2 flowing, [18F]3FDA or [18F]6FDA was separated by semi-preparative HPLC (Column: Nakarai
Cosmosil Sugar-D, 10 mmI.D.×20+250 mm, eluent: CH3CN/H2O=3:1, flow rate: 2 mL/min, retention
time: 13.9 min for [18F]3FDA, 11.1 min for [18F]6FDA) with PD1A radio-detector (UNIVERSAL GIKEN,
Kanagawa, Japan).
4.17
manual operation synthesis
In total, 50–60 MBq of no-carrier-added [18F]fluoride in water (ca. 1 mL) was adsorbed to a
General procedures for synthesis of [18F]3FDA and [18F]6FDA from 4b and 5b, respectively, by
Waters Sep-Pak Accell Plus QMA Plus Light Cartridge, which was activated by 1 mol/L aqueous K2CO3
(10 mL) and water (30 mL). The [18F]Fluoride was desorbed by a mixture of K2CO3 (17 µmol), cryptand

222 (34 µmol), water (0.2 mL), and CH3CN (0.7 mL). The eluent was concentrated by heating to 85 °C
with N2 flowing. CH3CN (1 mL) was added to the residue and azeotropically dried by heating to 85 °C
with N2 flowing. After a CH3CN (3 mL) solution of 4b (30 mg, 42 µmol) or 5b (30 mg, 42 µmol) was
added to the residue and the mixture was stirred at 85 °C for
1,2,4,6-tetra-O-benzoyl-3-deoxy-3-[18F]fluoro-β-D-allopyranose ([18F]11b)
5
min,
or
1,2,3,4-tetra-O-benzoyl-6-deoxy-6-[18F]fluoro-β-D-allopyranose ([18F]12b) was obtained at 85% or 88%
RCC, respectively, as determined by silica gel TLC (Rf 0.39 for [18F]11b, 0.36 for [18F]12b, eluent:
toluene/AcOEt=9:1) using authentic non-radioactive samples 11b or 12b. After concentration by heating
to 85 °C with N2 flowing and cooling to rt, the residue was dissolved in tetrahydrofuran (1 mL), and 0.3
mol/L aqueous NaOH (1 mL) was added to the solution, after which the mixture was shaken, and it stood
at rt for 30 min. Then, after 1 mol/L aqueous CH3CO2H (0.5 mL) was added to the reaction mixture,
[18F]3FDA or [18F]6FDA was obtained at 33% or 26% RCC, respectively which was determined by silica
gel TLC (Rf 0.38 for [18F]3FDA, 0.39 for [18F]6FDA, eluent: CHCl3/MeOH=2:1) using authentic
non-radioactive samples 3FDA or 6FDA. After concentration by heating to 85 °C with N2 flowing,
[18F]3FDA or [18F]6FDA was separated by semi-preparative HPLC (Column: Nakarai Cosmosil Sugar-D,
10 mmI.D.×20+250 mm, eluent: CH3CN/H2O=3:1, flow rate: 2 mL/min, retention time: 13.9 min for
[18F]3FDA, 11.1 min for [18F]6FDA) with a PD1A radio-detector (UNIVERSAL GIKEN, Kanagawa,
Japan).

4.18
Synthesis of [18F]3FDA from 3 by manual operation synthesis
In total, 50–60 MBq of no-carrier-added [18F]fluoride in water (ca. 1 mL) was adsorbed to a
Waters Sep-Pak Accell Plus QMA Plus Light Cartridge, which was activated by 1 mol/L aqueous K2CO3
(10 mL) and water (30 mL). [18F]Fluoride was desorbed by a mixture of K2CO3 (17 µmol), cryptand 222
(34 µmol), water (0.2 mL), and CH3CN (0.7 mL). The eluent was concentrated by heating to 85 °C with
N2 flowing. CH3CN (1 mL) was added to the residue and azeotropically dried by heating to 85 °C with N2
flowing. A CH3CN (1 mL) solution of 3 (16.3 mg, 42 µmol) was added to the residue and the mixture was
stirred at 85 °C for 1 h, assumed 1,2:5,6-di-O-isopropylidene-3-deoxy-3-[18F]fluoro-α-D-allofuranose
([18F]13) was obtained at 9% RCC by silica gel TLC (Rf 0.62, eluent: hexane/AcOEt=1:1). After
concentration by heating to 85 °C with N2 flowing, 1 mol/L aqueous HCl (1 mL) was added to the residue,
and the mixture was stirred at 85 °C for 50 min. [18F]3FDA was obtained at 4% RCC, determined by
silica gel TLC (Rf 0.39, eluent: CHCl3/MeOH=2:1) using authentic non-radioactive sample 1. After
concentration by heating to 85 °C with N2 flowing, [18F]3FDA was separated by semi-preparative HPLC
(Column: Nakarai Cosmosil Sugar-D, 10 mmI.D.×20+250 mm, eluent: CH3CN/H2O=3:1, flow rate: 2
mL/min, retention time: 13.9 min) with a PD1A radio-detector (UNIVERSAL GIKEN, Kanagawa,
Japan).