Stereocontrolled facile synthesis and biological evaluation of (3 S) and (3 R)-3-Amino (and Azido)-3-deoxy pyranonucleosides

Article abstract of DOI:10.1080/15257770.2012.696759

This article describes the synthesis of (3 S) and (3 R)-3-amino-3-deoxy pyranonucleosides and their precursors (3 S) and (3 R)-3-azido-3-deoxy pyranonucleosides. Azidation of 1,2:5,6-di-O-isopropylidene-3-O-toluenesulfonyl- α-D-allofuranose followed by hy

Full text of DOI:10.1080/15257770.2012.696759

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Stereocontrolled Facile Synthesis
and Biological Evaluation of (3′S) and
(3′R)-3′-Amino (and Azido)-3′-Deoxy
Pyranonucleosides
Stella Manta a , Vanessa Parmenopoulou a , Christos Kiritsis a , Athina
Dimopoulou a , Nikolaos Kollatos a , Ioannis Papasotiriou b , Jan
Balzarini c & Dimitri Komiotis a
a Laboratory of Bio-Organic Chemistry Department of Biochemistry
and Biotechnology, University of Thessaly, Larissa, Greece
b Research Genetic Cancer Center (R.G.C.C. Ltd.), GR, Filotas,
Greece
c Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
To cite this article: Stella Manta , Vanessa Parmenopoulou , Christos Kiritsis , Athina Dimopoulou ,
Nikolaos Kollatos , Ioannis Papasotiriou , Jan Balzarini & Dimitri Komiotis (2012): Stereocontrolled
Facile Synthesis and Biological Evaluation of (3′S) and (3′R)-3′-Amino (and Azido)-3′-Deoxy
Pyranonucleosides, Nucleosides, Nucleotides and Nucleic Acids, 31:7, 522-535
To link to this article: http://dx.doi.org/10.1080/15257770.2012.696759
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Nucleosides, Nucleotides and Nucleic Acids, 31:522–535, 2012
Copyright ꢀC Taylor and Francis Group, LLC
ISSN: 1525-7770 print / 1532-2335 online
DOI: 10.1080/15257770.2012.696759
STEREOCONTROLLED FACILE SYNTHESIS AND BIOLOGICAL
EVALUATION OF (3ꢀS) AND (3ꢀR)-3ꢀ-AMINO (AND AZIDO)-3ꢀ-DEOXY
PYRANONUCLEOSIDES
Stella Manta,1 Vanessa Parmenopoulou,1 Christos Kiritsis,1 Athina
Dimopoulou,1 Nikolaos Kollatos,1 Ioannis Papasotiriou,2 Jan Balzarini,3
and Dimitri Komiotis1
1Laboratory of Bio-Organic Chemistry, Department of Biochemistry and Biotechnology,
University of Thessaly, Larissa, Greece
2Research Genetic Cancer Center (R.G.C.C. Ltd.), GR, Filotas, Greece
3Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
This article describes the synthesis of (3 ꢁS) and (3 ꢁR)-3 ꢁ-amino-3 ꢁ-deoxy pyranonucleo-
2
sides and their precursors (3 ꢁS) and (3 ꢁR)-3 ꢁ-azido-3 ꢁ-deoxy pyranonucleosides. Azidation of
1,2:5,6-di-O-isopropylidene-3-O-toluenesulfonyl-α-D-allofuranose followed by hydrolysis and sub-
sequent acetylation afforded 3-azido-3-deoxy-1,2,4,6-tetra-O-acetyl-D-glucopyranose, which upon
coupling with the proper silylated bases, deacetylation, and catalytic hydrogenation, obtained
the target 3 ꢁ-amino-3 ꢁ-deoxy-β-D-glucopyranonucleosides. The desired 1-(3 ꢁ-amino-3 ꢁ-deoxy-β-D-
allopyranosyl)5-fluorouracil was readily prepared from the suitable imidazylate sugar after azidation
followed by a protection/deprotection sequence and reduction of the unprotected azido precursor. No
antiviral activity was observed for the novel nucleosides. Moderate cytostatic activity was recorded
for the 5-fluorouracil derivatives.
Keywords Azido pyranonucleosides; amino pyranonucleosides; cytostatic activity; 5-
fluorouracil
INTRODUCTION
The nucleosides embrace a large family of natural and chemically modi-
fied analogs of a great structural diversity and a broad spectrum of biological
Received 11 April 2012; accepted 21 May 2012.
This work was supported in part by the Postgraduate Programs “Biotechnology-Quality Assessment
in Nutrition and the Environment,” “Application of Molecular Biology–Molecular Genetics–Molecular
Markers,” Department of Biochemistry and Biotechnology, University of Thessaly and the K.U. Leuven
(GOA 10/014). The authors thank Mrs. Lizette van Berckelaer, Mrs. Leentje Persoons, Mrs. Frieda De
Meyer, Mrs. Anita Camps, Mrs. Lies Van den Heurck, Mr. Steven Carmans, and Mrs. Leen Ingels for
excellent technical assistance.
Address correspondence to Dimitri Komiotis, Laboratory of Bio-organic Chemistry, Department of
Biochemistry & Biotechnology, University of Thessaly, 26 Ploutonos Str., 41221 Larissa, Greece. E-mail:
dkom@bio.uth.gr
522

Stereocontrolled Facile Synthesis of Amino and Azido Pyranonucleosides
523
activity.[1–5] The analogs of natural nucleosides and nucleoside antibiotics
belong to the most important classes of antiviral drugs, and they are exten-
sively used in the treatment of a variety of cancers. However, the emergence
of drug-resistant mutants that render current therapies ineffective, drives
interest in the development of novel nucleoside analogs with high potency,
low toxicity, and favorable resistance profiles.[6]
The aminosugar nucleosides are well-known bioactive agents,[7–9] of
which puromycin, a protein synthesis inhibitor, is one of the most important
examples.[10–12] In addition, their azidosugar precursors[13–16] have been at-
tracting growing attention, since 3ꢁ-azido-2ꢁ,3ꢁ-dideoxycytidine (AZC) and
guanosine (AZG) nucleosides[14,17,18] exhibit an inhibiting activity on the
replication of the human immunodeficiency virus (HIV), while the thymi-
dine derivative (AZT) is a widely utilized anti-HIV drug.[19]
Lately, the pyranosyl nucleosides are among the most recent modifi-
cations of the natural nucleosides to receive attention as potential antivi-
ral,[20,21] antibiotic,[22] antioxidant,[23,24] and antitumor[5] agents. Their bi-
ological activity is often modulated by the systematic variation of the sugar
ring and/or the nucleic base. Modified nucleosides with a six-membered
sugar ring containing fluoro, keto,[25–30] exomethylene,[31,32] cyano,[33] and
ethynyl[34] functions, proved to have a promising potential in combating
rotaviral infections and exhibited cytostatic activity against various cancer
cell lines. Experimental data revealed that thymidylate synthase,[35] human
poly(A)-specific ribonuclease,[36] and glycogen phosphorylase[37] are among
the molecular targets of these compounds.
Based on these findings and as a continuation of our investigations con-
cerning the development of bioactive sugar-modified pyranonucleosides, it
was of great interest to design, synthesize, and biologically evaluate novel
(3ꢁS) and (3ꢁR)-3ꢁ-amino (and azido)-3ꢁ-deoxy pyranonucleosides, i.e., 3ꢁ-
amino (and azido)-3ꢁ-deoxy-β-d-glucopyranonucleosides and 3ꢁ-amino (and
azido)-3ꢁ-deoxy-β-d-allopyranonucleosides, bearing 5-fluorouracil, thymine,
cytosine, and guanine as heterocyclic bases.
RESULTS AND DISCUSSION
Chemistry
Our synthetic plan to the desired 3ꢁ-amino-3ꢁ-deoxy-β-d-glucopyranonu-
cleosides 7a,b,e,f and their azido precursors 6a,b,e,f was focused on the
preparation of the glycosyl donor from a chiral template, carbohydrate pre-
cursor, and then the condensation with nucleosidic bases. Synthesis of the
key d-glycosyl donor 4[38] from diacetone-d-glucose (1), is shown in Figure 1.
Thus, oxidation of the commercially available 1,2:5,6-di-O-
isopropylidene-α-d-glucofuranose (1) followed by stereoselective reduction

524
S. Manta et al.
FIGURE 1 (i) NaN3, DMF; (ii) (a) MeOH, H2O, Amberlite IR 120 (H+); (b) pyridine, Ac2O; (iii)
nucleobase, HMDS, Me3SiOSO2CF3, saccharine, CH3CN; (iv) ammonia/MeOH; (v) H2, 10% Pd/C,
triethylamine, EtOAc, EtOH, 20◦C, 24 hours.
and tosylation, gave the corresponding 1,2:5,6-di-O-isopropylidene-3-O-
toluenesulfonyl-α-d-allofuranose (2).[39,40] The endo-sulfonate group of
furanose 2[39,40] was readily displaced with azide ion in boiling N ,N -
dimethylformamide (DMF). Hydrolysis of the resulting azide 3 using the
Amberlite IR 120 (H+) resin followed by the subsequent treatment with Ac2O
in pyridine afforded a mixture of the anomeric acetates 4[38] (ratio of α to β
anomer, 0.57:0.43). The anomeric mixture 4[38] was readily converted into
the protected 1-(2ꢁ,4ꢁ,6ꢁ-tri-O-acetyl-3ꢁ-azido-3ꢁ-deoxy-β-d-glucopyranosyl)
nucleosides 5a–d,[41] upon reaction with silyl-protected 5-fluorouracil,
thymine, N 4-benzoylcytosine, and N 2-acetylguanine, respectively, in the
presence of trimethylsilyltrifluoromethane-sulfonate (Me3SiOSO2CF3) as
an activator.[42] 1H NMR data obtained for the newly synthesized nucleosides
5 showed a large coupling between protons H-1ꢁ, H-2ꢁ and H-2ꢁ, H-3ꢁ ( J 1 ,2
=
ꢁ
ꢁ
ꢁ
ꢁ
9.2–9.4 Hz, J 2 ,3 = 9.5–9.9 Hz), thus revealing the β-configuration of the
sugar moiety and an equatorially oriented azido group. Removal of all
the protecting groups of 5a–d, with saturated methanolic ammonia,[43]
furnished the target products 6a,b,e,f, in good yields (71–81%). The
infrared (IR) spectra of the 6a,b,e,f exhibited characteristic absorption
bands at 2107–2115 cm−1 due to the presence of the azido group. In the
final step, the azido derivatives 6a,b,e,f were reduced to form the desired
amino analogs 7a,b,e,f by hydrogen in the presence of palladium-on-carbon
(Table 1).

Stereocontrolled Facile Synthesis of Amino and Azido Pyranonucleosides
525
TABLE 1 Cytostatic activity of 6a,b,e,f, 7a,b,e,f, 12a, and 13a against suspension and monolayer tumor
cell lines
IC50a (µM)
Compound
L1210
CEM
HeLa
6a
6b
6e
6f
7a
7b
7e
7f
12a
13a
174 21
>250
>250
>250
>250
>250
>250
>250
>250
>250
>250
>250
>250
>250
>250
>250
≥250
171
6
92 17
>250
176 16
≥250
>250
>250
>250
119 10
232 25
244
≥250
174
8
4
a50% inhibitory concentration, or compound concentration required to inhibit cell proliferation by
50%.
The target amino pyranonucleosides 7a,b,e,f and their key intermediates
6a,b,e,f proved to be slightly cytostatic against the murine leukemia L1210,
the human lymphocyte CEM, and the human cervix carcinoma HeLa cells,
except the 5-fluorouracil analog 7a that proved to be the most cytotoxic
against L1210 cells (IC50: 92 µM).
To further explore the impact of the azido and amino orientation on
the biological activity, the most potent 5-fluorouracil nucleoside 7a was cho-
sen and its (3ꢁR)-diastereomer was also synthesized. Thus, 3-imidazylate ester
8
[44] appeared to be a suitable precursor for its synthesis, since the tosylate es-
ter of diacetone-d-glucose proved to be particularly resistant to nucleophilic
displacement reactions, presumably due to the exo-orientation of the sul-
fonate group[40,45] (Figure 1). Ester 8 was converted at 50◦C in DMF to the
azide 9 in 79% yield with inversion of configuration at the C3 center. Azidoly-
sis was followed by the quantitative cleavage of the isopropylidene protecting
groups of 9 and the subsequent direct standard acetylation afforded per-
acetylated allopyranose 10,[46] existing exclusively as its β-pyranose form. The
desired 5-fluorouracil nucleoside 11a was obtained by condensing the glyco-
syl donor 3-azido-3-deoxy-1,2,4,6-tetra-O-acetyl-β-d-allopyranose (10)[46] with
silylated 5-fluorouracil in the presence of Me3SiOSO2CF3 as a catalyst.[42] As
1
expected, its H NMR spectra showed a large coupling between protons
H-1ꢁ and H-2ꢁ ( J 1 ,2 = 9.4 Hz) and a small coupling between protons H-2ꢁ
ꢁ
ꢁ
and H-3ꢁ ( J 2 ,3 = 3.3 Hz), indicating an equatorially oriented base ring and
an axial oriented azido group, respectively. Deacetylation performed with
the saturated methanolic ammonia,[43] afforded the unprotected nucleo-
side 12a, in good yield (72%). In the final step, catalytic hydrogenation of
the azide precursor provided the target amino allopyranonucleoside 13a, in
78% yield.
ꢁ
ꢁ

526
S. Manta et al.
Biological Evaluation
The compounds have been evaluated against a broad panel of DNA and
RNA viruses, but were found to be inactive at the highest tested concentration
(100–200 µM). Also, none of the compounds showed pronounced cytostatic
or cytotoxic activity in the monolayer cell cultures used for the antiviral
assays. Among all the nucleosides tested, the fluorouracil derivatives 6a, 7a,
and 13a proved moderately cytostatic against L1210 (IC50: 92–174 µM) and
Hela cells (IC50: 174–176 µM), but not CEM cells (IC50 > 250 µM). The
guanine analogs 6f and 7f also proved moderately cytostatic against HeLa
cells (IC50: 171–244 µM).
EXPERIMENTAL
General Methods
Thin-layer chromatography (TLC) was performed on Merck precoated
60F254 plates. The reactions were monitored by the TLC on a silica gel, with
detection by the UV light (254 nm) or by charring with sulfuric acid. Flash
column chromatography (FCC) was performed using silica gel (240–400
1
mesh, Merck). The H and 13C NMR spectra were obtained at room tem-
perature with a Bruker 400 spectrometer at 400 and 100 MHz, respectively,
using chloroform-d (CDCl3), methanol-d4 (CD3OD), and dimethylsulfoxide-
d6 (DMSO-d6) with internal tetramethylsilane (TMS). The chemical shifts
(δ) were given in ppm and measured downfield from TMS, and spin–spin
coupling constants were in Hz. The UV–vis spectra were recorded on a PG
T70 UV–VIS spectrometer and the mass spectra were obtained on a Thermo
Quest Finnigan AQA Mass Spectrometer (electrospray ionization). The opti-
cal rotations were measured using an Autopol I polarimeter. The IR spectra
were obtained with a Thermo Scientific Nicolet IR100 FTIR spectrometer.
The acetonitrile (CH3CN) was distilled from calcium hydride and stored
over 3E molecular sieves. The DMF was stored over 3E molecular sieves.
3-Azido-3-deoxy-1,2:5,6-di-O-isopropylidene-α-d-glucofuranose (3)
A solution of the tosylate 2[39,40] (5.00 g, 12.1 mmol) in DMF (60.5 mL)
containing suspended sodium azide (NaN3) (2.35 g, 36.2 mmol) was heated
under reflux for 4 hours. The DMF was removed under reduced pressure,
and the residue was dissolved in ethyl acetate (EtOAc). The organic phase
was washed with H2O (2×), dried over an anhydrous sodium sulfate, filtered,
and evaporated to dryness. The residue was purified by FCC (hexane–EtOAc
9:1) to give compound 3 (2.68 g, 78%, Rf = 0.29 in hexane–EtOAc 9:1) as
22
an oil. The 1H NMR spectra agreed fully with the recorded data.[40] [α]D
− 36 (c 0.65, CHCl3); 1H NMR (CDCl3): δ 5.73 (d, 1H, J 1,2 = 3.6 Hz, H-1),
4.61 (d, 1H, H-2), 4.24 (m, 1H, H-5), 4.16–4.07 (m, 3H, H-3, H-6a, H-6b),

Stereocontrolled Facile Synthesis of Amino and Azido Pyranonucleosides
527
3.98 (dd, 1H, J 3,4 = 4.8 Hz, J 4,5 = 8.6 Hz, H-4), 1.51, 1.43, 1.38, 1.32 (4s,
12H, 4CH3); ESI-MS (m/z): 286.27 [M+H+]. Anal. calcd. for C12H19N3O5:
C, 50.52; H, 6.71; N, 14.73. Found: C, 50.81; H, 6.43; N, 14.84.
3-Azido-3-deoxy-1,2,4,6-tetra-O-acetyl-d-glucopyranose (4)[38]
To a solution of compound 3 (2.68 g, 9.40 mmol) in methanol (MeOH)
(13.5 mL) and H2O (81 mL) was added Amberlite IR 120 (H+) (4.7 g) resin
and the mixture was refluxed overnight. The reaction mixture was filtered
and evaporated to dryness. The residue was then dissolved in a mixture of
pyridine (33 mL) and acetic anhydride (Ac2O) (17 mL). The reaction was
carried out at room temperature for 1 hour, then was quenched with MeOH
at 0◦C, and was concentrated in vacuum. The residue was diluted with EtOAc
and washed with saturated sodium bisulfate, sodium bicarbonate, and water.
The organic extract was dried over anhydrous sodium sulfate, filtered, and
evaporated to dryness to give anomeric acetates 4[38] (2.98 g, 85%, Rf =
22
0.27 in hexane–EtOAc 8:2) as a yellow foam. [α]D − 2 (c 0.20, CHCl3); 1H
ꢁ
ꢁ
ꢁ
ꢁ
NMR (CDCl3): δ 6.32 and 5.69 (α: d, J 1 ,2 = 3.6 Hz, 0.57H, H-1; β: d, J 1 ,2
=
8.2 Hz, 0.43H, H-1), 5.08–4.94 (m, 2H), 4.28–3.67 (m, 4H), 2.19–2.09 (2s,
12H, OAc). ESI-MS (m/z): 374.30 [M+H+]. Anal. calcd. for C14H19N3O9: C,
45.04; H, 5.13; N, 11.26. Found: C, 45.32; H, 4.79; N, 11.57.
General Procedure for Preparation of 3ꢀ-Azido-3ꢀ-deoxy-β-d-glucopyranonucleo-
sides 5a–d
A mixture of the proper base (6.97 mmol), hexamethyldisilazane
(HMDS) (8.64 mmol, 1.24 eq), and saccharine (0.32 mmol, 0.046 eq) in
anhydrous CH3CN (28 mL) was refluxed for 30 minutes under nitrogen.
3-Azido-3-deoxy-1,2,4,6-tetra-O-acetyl-d-glucopyranose (4)[38] (5.36 mmol)
and Me3SiOSO2CF3 (7.50 mmol, 1.4 eq) were then added and the reaction
mixture was refluxed for 2 hours, cooled, neutralized with aqueous sodium
bicarbonate, and extracted with dichloromethane (CH2Cl2, 1000 mL). The
organic extract was dried over anhydrous sodium sulfate, filtered, and evap-
orated to dryness. The residue was purified by FCC to give compounds 5, in
60–87% yields as yellow oils.
1-(2ꢁ,4ꢁ,6ꢁ-Tri-O-acetyl-3ꢁ-azido-3ꢁ-deoxy-β-d-glucopyranosyl)5-fluorouracil (5a).
22
Yield 87%; Rf = 0.37 (EtOAc–hexane 1:1); [α]D + 2 (c 0.40, CHCl3);
1
λmax 265 nm (ε 2219); H NMR (CDCl3): δ 7.43 (d, 1H, J 6,F5 = 5.7 Hz,
H-6), 5.82 (dd, 1H, J 1 ,2 = 9.3 Hz, J 1 ,F5 = 1.4 Hz, H-1ꢁ), 5.05 (t, 1H, J =
10.1 Hz, H-4ꢁ), 4.98 (t, 1H, J = 9.6 Hz, H-2ꢁ), 4.28−4.11 (m, 2H, H-6aꢁ,
H-6bꢁ), 3.93−3.86 (m, 2H, H-3ꢁ, H-5ꢁ), 2.17, 2.11 (2s, 9H, 3OAc). ESI-MS
(m/z): 444.37 [M+H+]. Anal. calcd. for C16H18FN5O9: C, 43.35; H, 4.09; N,
15.80. Found: C, 43.14; H, 4.41; N, 16.14.
ꢁ
ꢁ
ꢁ
1-(2ꢁ,4ꢁ,6ꢁ-Tri-O-acetyl-3ꢁ-azido-3ꢁ-deoxy-β-d-glucopyranosyl)thymine
(5b).
22
Yield 85%; Rf = 0.40 (EtOAc–hexane 8:2); [α]D − 2 (c 0.27, CHCl3); λmax
1
260 nm (ε 3479); H NMR (CDCl3): δ 8.40 (br s, 1H, NH), 7.13 (s, 1H,

528
S. Manta et al.
H-6), 5.81 (d, 1H, J 1 ,2 = 9.3 Hz, H-1ꢁ), 5.03 (t, 2H, J = 9.9 Hz, H-2ꢁ, H-4ꢁ),
4.26–4.08 (m, 2H, H-6aꢁ, H-6bꢁ), 3.89–3.83 (m, 2H, H-3ꢁ, H-5ꢁ), 2.16, 2.10,
2.08 (3s, 9H, 3OAc), 1.96 (s, 3H, 5-CH3). ESI-MS (m/z): 440.40 [M+H+].
Anal. calcd. for C17H21N5O9: C, 46.47; H, 4.82; N, 15.94. Found: C, 46.13;
H, 4.56; N, 16.23.
ꢁ
ꢁ
1-(2ꢁ,4ꢁ,6ꢁ-Tri-O-acetyl-3ꢁ-azido-3ꢁ-deoxy-β-d-glucopyranosyl)N 4-benzoylcytosine
22
(5c). Yield 82%; Rf = 0.27 (EtOAc–hexane 8:2); [α]D + 2 (c 0.20,
1
CHCl3); λmax 264 nm (ε 4151); H NMR (CDCl3): δ 8.14–7.53 (m, 7H,
Bz, H-5 and H-6), 6.03 (d, 1H, J 1 ,2 = 9.4 Hz, H-1ꢁ), 5.11–4.99 (m, 2H,
H-2ꢁ, H-4ꢁ), 4.27–4.09 (m, 2H, H-6aꢁ, H-6bꢁ), 3.97–3.92 (m, 2H, H-3ꢁ, H-5ꢁ),
2.17, 2.09 (2s, 9H, 3OAc). ESI-MS (m/z): 529.49 [M+H+]. Anal. calcd. for
C23H24N6O9: C, 52.27; H, 4.58; N, 15.90. Found: C, 52.66; H, 4.24; N, 16.05.
9-(2ꢁ,4ꢁ,6ꢁ-Tri-O-acetyl-3ꢁ-azido-3ꢁ-deoxy-β-d-glucopyranosyl)N 2-acetylguanine
ꢁ
ꢁ
22
(5d). Yield 60%; Rf = 0.38 (EtOAc); [α]D − 4 (c 0.20, CHCl3); λmax
1
270 nm (ε 2018); H NMR (CD3OD): δ 8.11 (s, 1H, H-8), 5.80 (d, 1H,
J 1 ,2 = 9.2 Hz, H-1ꢁ), 5.71 (t, 1H, J = 9.5 Hz, H-2ꢁ), 5.16 (t, 1H, J = 9.9 Hz,
H-4ꢁ), 4.28–4.12 (m, 4H, H-6aꢁ, H-6bꢁ, H-3ꢁ, H-5ꢁ), 2.25, 2.17, 2.04, 1.90 (4s,
12H, 4OAc). ESI-MS (m/z): 507.40 [M+H+]. Anal. calcd. for C19H22N8O9:
C, 45.06; H, 4.38; N, 22.13. Found: C, 45.24; H, 4.14; N, 22.32.
ꢁ
ꢁ
General Procedure for Preparation of 3ꢀ-Azido-3ꢀ-deoxy-β-d-glucopyranonu-
cleosides 6a,b,e,f
The protected nucleosides 5 (1 mmol) were treated with ammo-
nia/MeOH (saturated at 0◦C, 41.8 mL) overnight at room temperature.
The solvent was evaporated under reduced pressure to afford pure 6, in
71–81% yields as white foams.
1-(3ꢁ-Azido-3ꢁ-deoxy-β-d-glucopyranosyl)5-fluorouracil (6a). Yield 78%; Rf =
22
0.36 (EtOAc); [α]D − 4 (c 0.20, MeOH); λmax 266 nm (ε 1467); IR (Nujol,
cm−1): 2111 (N3); 1H NMR (DMSO-d6): δ 8.15 (d, 1H, J 6,F5 = 7.2 Hz, H-6),
5.83 (d, 1H, J 4 -OH,4 = 5.6 Hz, 4ꢁ-OH), 5.62 (d, 1H, J 2 -OH,2 = 6.5 Hz, 2ꢁ-OH),
ꢁ
ꢁ
ꢁ
ꢁ
5.47 (dd, 1H, J 1 ,2 = 8.9 Hz, J 1 ,F5 = 1.7 Hz, H-1ꢁ), 4.59 (t, 1H, J = 5.7 Hz,
6ꢁ-OH), 3.75–3.66 (m, 1H, H-2ꢁ), 3.65–3.58 (m, 1H, H-4ꢁ), 3.55–3.42 (m, 4H,
H-3ꢁ, H-5ꢁ, H-6aꢁ, H-6bꢁ); 13C NMR (DMSO-d6): 157.1, 149.3, 139.5, 126.9,
95.1, 86.4, 70.4, 64.2, 63.7, 55.6; ESI-MS (m/z): 318.25 [M+H+]. Anal. calcd.
for C10H12FN5O6: C, 37.86; H, 3.81; N, 22.08. Found: C, 37.59; H, 3.95; N,
21.85.
ꢁ
ꢁ
ꢁ
1-(3ꢁ-Azido-3ꢁ-deoxy-β-d-glucopyranosyl)thymine (6b). Yield 81%; Rf = 0.48
22
(CH2Cl2–MeOH 8:2); [α]D − 2 (c 0.20, MeOH); λmax 264 nm (ε 1547); IR
(Nujol, cm−1): 2107 (N3); 1H NMR (CD3OD): δ 7.52 (s, 1H, H-6), 5.56 (d,
1H, J 1 ,2 = 9.2 Hz, H-1ꢁ), 3.82 (dd, 1H, J 6a,6b = 12.1 Hz, J 5,6a = 1.9 Hz, H-6a),
3.70 (dd, 1H, J 5,6b = 4.7 Hz, H-6b), 3.59 (t, 1H, J = 9.2 Hz, H-2ꢁ), 3.50–3.44
(m, 3H, H-3ꢁ, H-4ꢁ, H-5ꢁ), 1.87 (s, 3H, 5-CH3); 13C NMR (CD3OD): 162.4,
148.5, 136.9, 112.3, 96.7, 82.1, 68.1, 66.0, 62.6, 54.8, 11.7; ESI-MS (m/z):
ꢁ
ꢁ

Stereocontrolled Facile Synthesis of Amino and Azido Pyranonucleosides
529
314.29 [M+H+]. Anal. calcd. for C11H15N5O6: C, 42.17; H, 4.83; N, 22.36.
Found: C, 41.81; H, 4.97; N, 22.48.
1-(3ꢁ-Azido-3ꢁ-deoxy-β-d-glucopyranosyl)cytosine (6e). Yield 71%; Rf = 0.25
22
(EtOAc–MeOH 9:1); [α]D − 20 (c 0.20, MeOH); λmax 259 nm (ε 1894); IR
(Nujol, cm−1): 2111 (N3); 1H NMR (CD3OD): δ 7.66 (d, 1H, J 5,6 = 7.6 Hz,
H-6), 5.91 (d, 1H, H-5), 5.68 (d, 1H, J 1 ,2 = 8.8 Hz, H-1ꢁ), 3.83 (m, 1H, H-2ꢁ),
3.73–3.46 (m, 5H, H-3ꢁ, H-4ꢁ, H-5ꢁ, H-6aꢁ, H-6bꢁ); 13C NMR (CD3OD): 167.4,
153.8, 141.7, 96.1, 95.3, 82.3, 68.3, 66.3, 60.8, 56.9; ESI-MS (m/z): 299.24
[M+H+]. Anal. calcd. for C10H14N6O5: C, 40.27; H, 4.73; N, 28.18. Found:
C, 40.65; H, 4.37; N, 28.36.
ꢁ
ꢁ
9-(3ꢁ-Azido-3ꢁ-deoxy-β-d-glucopyranosyl)guanine (6f). Yield 76%; Rf = 0.4
22
(EtOAc–MeOH 7:3); [α]D − 40 (c 0.20, MeOH); λmax 278 nm (ε 1203);
IR (Nujol, cm−1): 2115 (N3); 1H NMR (DMSO-d6): δ 7.87 (s, 1H, H-8), 6.48
(br s, 2H, NH2), 5.84 (d, 1H, J 4 -OH,4 = 6.1 Hz, 4ꢁ-OH), 5.84 (d, 1H, J 2 -OH,2
ꢁ
ꢁ
ꢁ
ꢁ
= 5.6 Hz, 2ꢁ-OH), 5.23 (d, 1H, J 1 ,2 = 9.3 Hz, H-1ꢁ), 4.66 (t, 1H, J = 5.7 Hz,
6ꢁ-OH), 3.95 (m, 1H, H-2ꢁ), 3.68–3.63 (m, 1H, H-4ꢁ), 3.52–3.39 (m, 4H, H-3ꢁ,
H-5ꢁ, H-6aꢁ, H-6bꢁ); 13C NMR (DMSO-d6): 156.2, 155.3, 148.8, 136.1, 116.7,
97.8, 81.5, 68.9, 66.5, 62.3, 55.9; ESI-MS (m/z): 339.27 [M+H+]. Anal. calcd.
for C11H14N8O5: C, 39.06; H, 4.17; N, 33.12. Found: C, 38.81; H, 3.90; N,
32.93.
ꢁ
ꢁ
General Procedure for Preparation of 3ꢀ-Amino-3ꢀ-deoxy-β-d-glucopyranonu-
cleosides 7a,b,e,f
After two vacuum/H2 cycles to remove air from the reaction tube, the
stirred mixture of nucleosides 6 (1 mmol), Pd/C (139 mg), and triethy-
lamine (272 µL, 1.96 mmol) in EtOAc (31 mL) and ethanol (EtOH) (31 mL)
was hydrogenated at ambient pressure (balloon) and temperature (ca. 20◦C)
for 24 hours. The reaction mixture was filtered and the filtrate was concen-
trated in vacuum to give pure 7, in 60–79% yields as white foams.
1-(3ꢁ-Amino-3ꢁ-deoxy-β-d-glucopyranosyl)5-fluorouracil (7a). Yield 76%; Rf
22
= 0.41 (CH2Cl2/MeOH 1:1); [α]D + 2 (c 0.20, DMSO); λmax 260 nm
(ε 1147); 1H NMR (DMSO-d6): δ 7.88 (d, 1H, J 6,F5 = 6.9 Hz, H-6), 5.36 (d,
1H, J 1 ,2 = 9.0 Hz, H-1ꢁ), 3.49–3.12 (m, 8H, H-2ꢁ, H-4ꢁ, H-5ꢁ, H-6aꢁ, H-6bꢁ,
3OH), 2.68 (t, 1H, J = 9.3 Hz, H-3ꢁ), 1.74 (s, 2H, NH2); 13C NMR (DMSO-d6):
155.1, 149.8, 138.6, 127.2, 95.3, 81.3, 72.7, 66.8, 64.6, 55.8; ESI-MS (m/z):
292.25 [M+H+]. Anal. calcd. for C10H14FN3O6: C, 41.24; H, 4.85; N, 14.43.
Found: C, 40.99; H, 4.56; N, 14.80.
ꢁ
ꢁ
1-(3ꢁ-Amino-3ꢁ-deoxy-β-d-glucopyranosyl)thymine (7b). Yield 72%; Rf = 0.2
22
(EtOAc–MeOH 4:6); [α]D + 4 (c 0.20, DMSO); λmax 262 nm (ε 1554); 1H
NMR (DMSO-d6): δ 7.50 (s, 1H, H-6), 5.32 (d, 1H, J 1 ,2 = 9.2 Hz, H-1ꢁ), 4.54
(br s, 1H, OH), 3.66–3.42 (m, 6H, H-4ꢁ, H-5ꢁ, H-6aꢁ, H-6bꢁ, 2OH), 3.06 (t,
1H, J = 9.5 Hz, H-2ꢁ), 2.67 (t, 1H, J = 9.3 Hz, H-3ꢁ), 1.77 (s, 2H, NH2), 1.73
(s, 3H, CH3); 13C NMR (DMSO-d6): 160.9, 151.7, 136.4, 111.2, 98.1, 84.8,
ꢁ
ꢁ

530
S. Manta et al.
70.1, 68.0, 60.1, 52.2, 13.0; ESI-MS (m/z): 288.32 [M+H+]. Anal. calcd. for
C11H17N3O6: C, 45.99; H, 5.96; N, 14.63. Found: C, 45.74; H, 6.11; N, 14.27.
1-(3ꢁ-Amino-3ꢁ-deoxy-β-d-glucopyranosyl)cytosine (7e). Yield 79%; Rf = 0.28
22
1
(MeOH); [α]D + 1 (c 0.20, DMSO); λmax 270 nm (ε 3031); H NMR
(DMSO-d6): δ 7.49 (d, 1H, J 5,6 = 7.5 Hz, H-6), 5.70 (d, 1H, H-5), 5.47 (d,
1H, J 1 ,2 = 9.3 Hz, H-1ꢁ), 3.66–3.40 (m, 7H, H-4ꢁ, H-5ꢁ, H-6aꢁ, H-6bꢁ, 3OH),
3.01 (t, 1H, J = 9.4 Hz, H-2ꢁ), 2.68 (t, 1H, J = 9.3 Hz, H-3ꢁ), 1.87 (s, 2H,
NH2); 13C NMR (DMSO-d6): 163.9, 153.7, 140.3, 97.7, 91.7, 85.4, 70.1, 66.8,
61.3, 54.8; ESI-MS (m/z): 273.25 [M+H+]. Anal. calcd. for C10H16N4O5: C,
44.12; H, 5.92; N, 20.58. Found: C, 44.41; H, 5.74; N, 20.31.
ꢁ
ꢁ
1-(3ꢁ-Amino-3ꢁ-deoxy-β-d-glucopyranosyl)guanine (7f). Yield 60%; Rf = 0.18
22
1
(MeOH); [α]D + 2 (c 0.20, DMSO); λmax 273 nm (ε 2764); H NMR
(DMSO-d6): δ 8.16 (br s, 1H, NH), 7.86 (s, 1H, H-8), 6.49 (s, 2H, NH2), 6.14
(s, 1H, OH), 5.56 (s, 1H, OH), 5.22 (d, 1H, J 1 ,2 = 9.3 Hz, H-1ꢁ), 4.67–4.58
(m, 2H, H-2ꢁ, H-4ꢁ), 3.67–3.49 (m, 5H, H-3ꢁ, H-5ꢁ, H-6aꢁ, H-6bꢁ, OH), 1.86 (s,
2H, 3ꢁ-NH2); 13C NMR (DMSO-d6): 156.6, 151.7, 151.3, 136.2, 116.5, 96.5,
81.4, 70.8, 67.9, 62.0, 55.9; ESI-MS (m/z): 313.29 [M+H+]. Anal. calcd. for
C11H16N6O5: C, 42.31; H, 5.16; N, 26.91. Found: C, 42.59; H, 5.56; N, 26.57.
ꢁ
ꢁ
3-Azido-3-deoxy-1,2:5,6-di-O-isopropylidene-α-d-allofuranose (9)
A solution of the imidazylate sugar 8[44] (1.00 g, 2.56 mmol) in DMF
(12.8 mL) was added slowly to a solution of NaN3 (499 mg, 7.68 mmol) at
50◦C. The reaction was complete after 12 hours stirring at 50◦C. DMF was
removed under reduced pressure, and the residue was dissolved in EtOAc.
The organic phase was washed with H2O (2×), dried over anhydrous sodium
sulfate, filtered, and evaporated to dryness. The residue was purified by
FCC (hexane–EtOAc 3:1) to give compound 9 (576 mg, 79%, Rf = 0.22 in
1
hexane–EtOAc 3:1) as a colorless liquid. The H NMR spectra agreed fully
with the recorded data.[47] 1H NMR (CDCl3): δ 5.80 (d, 1H, J 1,2 = 3.7 Hz,
H-1), 4.74 (t, J = 4.6 Hz, H-2), 4.24–3.98 (m, 4H, H-4, H-5, H-6a, H-6b), 3.54
(dd, J 2,3 = 4.7 Hz, J 3,4 = 9.0 Hz, H-3), 1.60, 1.50, 1.40, 1.39 (4s, 12H, 4CH3).
ESI-MS (m/z): 286.32 [M+H+]. Anal. calcd. for C12H19N3O5: C, 50.52; H,
6.71; N, 14.73. Found: C, 50.78; H, 7.08; N, 14.57.
3-Azido-3-deoxy-1,2,4,6-tetra-O-acetyl-β-d-allopyranose (10)[46]
Compound 10[46] was prepared from compound 9 according to
the general method described for compound 4. Yield 69%; Rf = 0.22
22
1
(EtOAc–hexane 1:3); [α]D − 16 (c 0.20, CHCl3); H NMR (CDCl3): δ
5.97 (d, 1H, J 1,2 = 8.5 Hz, H-1), 4.99–4.94 (m, 2H, H-2, H-4), 4.48 (t, 1H,
ꢁ
J 2,3 = J 3,4 = 3.4 Hz, H-3), 4.29 (dd, 1H, J 5,6 = 4.4 Hz, J 6,6 = 12.4 Hz, H-
6a), 4.21–4.13 (m, 2H, H-5, H-6b), 2.14, 2.13, 2.09 (3s, 12H, 4OAc). ESI-MS
(m/z): 374.33 [M+H+]. Anal. calcd. for C14H19N3O9: C, 45.04; H, 5.13; N,
11.26. Found: C, 45.35; H, 4.87; N, 11.36.

Stereocontrolled Facile Synthesis of Amino and Azido Pyranonucleosides
531
1-(2ꢀ,4ꢀ,6ꢀ-Tri-O-acetyl-3ꢀ-azido-3ꢀ-deoxy-β-d-allopyranosyl)5-fluorouracil
(11a)
Compound 11a was prepared according to the general method described
22
for compounds 5a–d. Yield 60%; Rf = 0.34 (EtOAc–hexane 1:1); [α]D + 8
(c 0.20, CHCl3); λmax 265 nm (ε 3169); 1H NMR (CDCl3): δ 8.67 (br s, 1H,
ꢁ
ꢁ
ꢁ
NH), 7.36 (d, 1H, J 6,F5 = 5.8 Hz, H-6), 6.10 (dd, 1H, J 1 ,2 = 9.4 Hz, J 1 ,F5
=
1.2 Hz, H-1ꢁ), 5.07 (dd, 1H, J 2 ,3 = 3.3 Hz, H-2ꢁ), 5.00 (dd, 1H, J 3 ,4 = 3.1 Hz,
ꢁ
ꢁ
ꢁ
ꢁ
ꢁ
ꢁ
ꢁ
ꢁ
ꢁ
ꢁ
ꢁ
J 4 ,5 = 9.7 Hz, H-4 ), 4.51 (t, 1H, H-3 ), 4.31–4.17 (m, 3H, H-5 , H-6a , H-6b ),
2.17, 2.12, 2.11 (3s, 9H, 3OAc). ESI-MS (m/z): 444.35 [M+H+]. Anal. calcd.
for C16H18FN5O9: C, 43.35; H, 4.09; N, 15.80. Found: C, 43.55; H, 4.24; N,
16.06.
1-(3ꢀ-Azido-3ꢀ-deoxy-β-d-allopyranosyl)5-fluorouracil (12a)
Compound 12a was prepared according to the general method described
for compounds 6a,b,e,f. Yield 72%; Rf = 0.22 (CH2Cl2–MeOH 8.5:1.5);
22
[α]D + 6 (c 0.20, MeOH); λmax 266 nm (ε 1671); IR (Nujol, cm−1): 2115
(N3); 1H NMR (CD3OD): δ 7.90 (d, 1H, J 6,F5 = 6.7 Hz, H-6), 5.78 (dd, 1H,
J 1 ,2 = 9.3 Hz, J 1 ,F5 = 1.6 Hz, H-1ꢁ), 4.21 (t, 1H, J = 3.2 Hz, H-3ꢁ), 3.92 (dd,
1H, H-2ꢁ), 3.86–3.68 (m, 4H, H-4ꢁ, H-5ꢁ, H-6aꢁ, H-6bꢁ).13C NMR (CD3OD):
157.8, 149.6, 141.2, 126.4, 95.3, 81.8, 71.3, 65.9, 60.2, 56.7; ESI-MS (m/z):
318.26 [M+H+]. Anal. calcd. for C10H12FN5O6: C, 37.86; H, 3.81; N, 22.08.
Found: C, 38.05; H, 4.02; N, 22.45.
ꢁ
ꢁ
ꢁ
1-(3ꢀ-Amino-3ꢀ-deoxy-β-d-allopyranosyl)5-fluorouracil (13a)
Compound 13a was prepared according to the general method described
22
for compounds 7a,b,e,f. Yield 78%; Rf = 0.18 (EtOAc–MeOH 8:2); [α]D
1
+ 2 (c 0.20, DMSO); λmax 264 nm (ε 1012); H NMR (DMSO-d6): δ 8.04
ꢁ
ꢁ
ꢁ
(d, 1H, J 6,F5 = 7.2 Hz, H-6), 5.85 (dd, 1H, J 1 ,2 = 8.7 Hz, J 1 ,F5 = 1.4 Hz,
H-1ꢁ), 5.63 (t, 1H, J = 4.6 Hz, H-3ꢁ), 5.31 (dd, 1H, H-2ꢁ), 5.15 (dd, 1H, J 4 ,5
ꢁ
ꢁ
= 8.3 Hz, H-4ꢁ), 3.82–3.55 (m, 6H, H-5ꢁ, H-6aꢁ, H-6bꢁ, 3OH), 1.22 (s, 2H,
NH2); 13C NMR (DMSO-d6): 157.8, 149.5, 142.4, 125.6, 96.5, 84.7, 71.8, 70.2,
60.0, 53.5; ESI-MS (m/z): 292.25 [M+H+]. Anal. calcd. for C10H14FN3O6: C,
41.24; H, 4.85; N, 14.43. Found: C, 40.87; H, 5.06; N, 14.72.
Antiviral Activity Assays
The antiviral assays, other than the anti-HIV assays, were based on the
inhibition of virus-induced cytopathicity or plaque formation in HEL [her-
pes simplex virus type 1 (HSV-1) (KOS), HSV-2 (G), vaccinia virus, vesicular
stomatitis virus, human cytomegalovirus (HCMV), and varicella-zoster virus
(VZV)], Vero (parainfluenza-3, reovirus-1, Sindbis virus, and Coxsackie B4),
HeLa (vesicular stomatitis virus, Coxsackie virus B4, and respiratory syn-
cytial virus) or MDCK [influenza A (H1N1; H3N2) and influenza B] cell
cultures. The confluent cell cultures (or nearly confluent for MDCK cells)

532
S. Manta et al.
in microtiter 96-well plates were inoculated with 100 CCID50 of virus (1
CCID50 being the virus dose to infect 50% of the cell cultures) or with 20
plaque-forming units (PFU) (for VZV) in the presence of varying concentra-
tions (100, 20, . . . µM) of the test compounds. The viral cytopathicity was
recorded as soon as it reached completion in the control virus-infected cell
cultures that were not treated with the test compounds. The antiviral activ-
ity was expressed as the EC50 or the compound concentration required to
reduce virus-induced cytopathogenicity or viral plaque (VZV) plaque forma-
tion by 50%. The minimal cytotoxic concentration (MCC) of the compounds
was defined as the compound concentration that caused a microscopically
visible alteration of cell morphology. Alternatively, the cytostatic activity of
the test compounds was measured based on the inhibition of cell growth.
HEL cells were seeded at a rate of 5 × 103 cells/well into 96-well microtiter
plates and allowed to proliferate for 24 hours. Then, the medium contain-
ing different concentrations of the test compounds was added. After three
days of incubation at 37◦C, the cell number was determined with a Coulter
counter. The cytostatic concentration was calculated as the CC50, or the com-
pound concentration required to reduce cell proliferation by 50% relative
to the number of cells in the untreated controls. The methodology of the
anti-HIV assays was as follows: human CEM (∼3 × 105 cells/cm3) cells were
infected with 100 CCID50 of HIV(IIIB) or HIV-2(ROD)/mL and seeded in
200 µL wells of a microtiter plate containing appropriate dilutions of the test
compounds. After four days of incubation at 37◦C, the HIV-induced CEM
giant cell formation was examined microscopically.
Antiproliferative Assays
The cytostatic effects of the test compounds on murine leukemia cells
(L1210), human T-lymphocyte cells (CEM), and human cervix carcinoma
cells (HeLa) were evaluated as follows: an appropriate number of cells sus-
pended in growth medium were allowed to proliferate in 200-µL-wells of
96-well-microtiter plates in the presence of variable amounts of test com-
pounds at 37◦C in a humidified CO2-controlled atmosphere. After 48 hours
(L1210), 72 hours (CEM), or 96 hours (HeLa), the number of cells was
counted in a Coulter counter. The IC50 value was defined as the compound
concentration required to inhibit cell proliferation by 50%.
REFERENCES
1. Galmarini, C.M.; Mackey, J.R.; Dumontet, C. Nucleoside analogues and nucleobases in cancer treat-
ment. Lancet Oncol. 2002, 3, 415–424.
2. De Clercq, E. Highlights in the discovery of antiviral drugs: A personal retrospective. J. Med. Chem.
2010, 53, 1438–1450.
3. De Clercq, E. In search of a selective therapy of viral infections. Antiviral Res. 2010, 85, 19–24.

Stereocontrolled Facile Synthesis of Amino and Azido Pyranonucleosides
533
4. Komiotis, D.; Manta, S.; Tsoukala, E.; Tzioumaki, N. Antiviral unsaturated nucleosides. Curr. Med.
Chem.: Anti-Infect. Agents 2008, 7, 219–244.
5. Tsoukala, E.; Manta, S.; Kiritsis, C.; Komiotis, D. Keto and exomethylene pyranonucleosides as
antitumor agents. Mini Rev. Med. Chem. 2012, 12, 255–275.
6. Meng, W.D.; Qing, F.L. Fluorinated nucleosides as antiviral and anti-tumor agents. Curr. Top. Med.
Chem. 2006, 6, 1499–1528.
7. Watanabe, K.A.; Beranek, J.; Friedman, H.A.; Fox, J.J. Nucleosides. XXVII. 3ꢁ-Amino-3ꢁ-
deoxyhexopyranosyl nucleosides. II. Synthesis of 1-(3ꢁ-amino-3ꢁ-deoxy-beta-d-glucopyranosyl) pyrim-
idines and related compounds. J. Org. Chem. 1965, 30, 2735–2739.
8. Friedman, H.A.; Watanabe, K.A.; Fox, J.J. Nucleosides. 43. 3ꢁ-Amino-3ꢁ-deoxyhexopyranosyl nucle-
osides. V. Studies on the preparation of aminoacyl derivatives of amino sugar nucleosides. J. Org.
Chem. 1967, 32, 3775–3780.
9. Beranek, J.; Friedman, H.A.; Watanabe, K.A.; Fox, J.J. Nucleosides XXVIII. 3ꢁ-Amino-3ꢁ-
deoxyhexopyranosyl nucleosides. Part III. Synthesis of 3ꢁ-amino-3ꢁ-deoxyhexopyranosyl adenines.
J. Heterocyclic Chem. 1965, 2, 188–191.
10. Suhadolnik, R.J. Nucleoside Antibiotics, Wiley-Interscience: New York, 1970; pp. 3–50.
11. Nakanishi, T.; Tomita, F.; Suzuki, T. Production of a new aminonucleoside, 9-(2ꢁ-Amino-2ꢁ-
deoxypentofuranosyl) guanine, by aerobacter sp. Agric. Biol. Chem. 1974, 38, 2465–2469.
12. Botta, O.; Moyroud, E.; Lobato, C.; Strazewski, P. Synthesis of 3ꢁ-azido- and 3ꢁ-amino-3ꢁ-
deoxyadenosine in both enantiomeric forms. Tetrahedron 1998, 54, 13529–13546.
13. Lin, T.S.; Chen, M.S.; McLaren, C.; Gao, Y.S.; Ghazzouli, I.; Prusoff, W.H. Synthesis and antiviral
activity of various 3ꢁ-azido, 3ꢁ-amino, 2ꢁ,3ꢁ-unsaturated, and 2ꢁ,3ꢁ-dideoxy analogues of pyrimidine
deoxyribonucleosides against retroviruses. J. Med. Chem. 1987, 30, 440–444.
14. Pathak, T. Azidonucleosides: Synthesis, reactions, and biological properties. Chem. Rev. 2002, 102,
1623–1668.
15. Timoshchuk, V.A.; Hogrefe, R.I.; Vaghefi, M.M. Improved and reliable synthesis of 3ꢁ-azido-2ꢁ,3ꢁ-
dideoxyguanosine derivatives. Nucleosides Nucleotides Nucleic Acids 2004, 23, 171–181.
16. Gadthula, S.; Chu, C.K.; Schinazi, R.F. Synthesis and anti-HIV activity of beta-d-3ꢁ-azido-2ꢁ,3ꢁ-
unsaturated nucleosides and beta-d-3ꢁ-azido-3ꢁ-deoxyribofuranosylnucleosides. Nucleosides Nucleotides
Nucleic Acids 2005, 24, 1707–1727.
17. Gurjar, M.K.; Pawar, S.M.; Rama Rao, A.V. A synthesis of 1,5-di-O-acetyl- 3-azido-2,3-dideoxy-d-
ribofuranose. J. Carbohydr. Chem. 1988, 7, 271–275.
18. Zhang, H.W; Detorio, M.; Herman, B.D; Solomon, S.; Bassit, L.; Nettles, J.H.; Obikhod, A.; Tao,
S.J.; Mellors, J.W.; Sluis-Cremer, N.; Coats, S.J.; Schinazi, R.F. Synthesis, antiviral activity, cytotoxicity
and cellular pharmacology of l-3ꢁ-azido-2ꢁ,3ꢁ-dideoxypurine nucleosides. Eur. J. Med. Chem. 2011, 46,
3832–3844.
19. Zhang, H.W.; Coats, S.J.; Bondada, L.; Amblard, F.; Detorio, M.; Asif, G.; Fromentin, E.; Solomon, S.;
Obikhod, A.; Whitaker, T.; Sluis-Cremer, N.; Mellors, J.W.; Schinazi, R.F. Synthesis and evaluation
of 3ꢁ-azido-2ꢁ,3ꢁ-dideoxypurine nucleosides as inhibitors of human immunodeficiency virus. Bioorg.
Med. Chem. Lett. 2010, 20, 60–64.
20. Verheggen, I.; Van Aerschot, A.; Toppet, S.; Snoeck, R.; Janssen, G.; Balzarini, J.; DeClercq, E.;
Herdewijn, P. Synthesis and antiherpes virus activity of 1,5-anhydrohexitol nucleosides. J. Med. Chem.
1993, 36, 2033–2040.
21. Verheggen, I.; Van Aerschot, A.; Van Meervelt, L.; Rozenski, J.; Wiebe, L.; Snoeck, R.; Andrei, G.;
Balzarini, J.; Claes, P.; De Clercq, E.; Herdewijn, P. Synthesis, biological evaluation, and structure
analysis of a series of new 1,5-anhydrohexitol nucleosides. J. Med. Chem. 1995, 38, 826–835.
22. Haouz, A.; Vanheusden, V.; Munier-Lehmann, H.; Froeyen, M.; Herdewijn, P.; Van Calenbergh,
S.; Delarue, M. Enzymatic and structural analysis of inhibitors designed against mycobacterium
tuberculosis thymidylate kinase, new insights into the phosphoryl transfer mechanism. J. Biol. Chem.
2003, 278, 4963–4971.
23. Spanou, C.; Manta, S.; Komiotis, D.; Dervishi, A.; Kouretas, D. Antioxidant activity of a series of
fluorinated pyrano-nucleoside analogues of N 4-benzoyl cytosine and N 6-benzoyl adenine. Int. J. Mol.
Sci. 2007, 8, 695–704.
24. Spanou, C.; Tzioumaki, N.; Manta, S.; Margaris, P.; Kouretas, D.; Komiotis, D.; Liadaki, K. Unsat-
urated keto and exomethylene pyranonucleoside analogues of thymine and uracil exhibit potent
antioxidant properties. Pharmacol. Pharm. 2011, 2, 122–126.

534
S. Manta et al.
25. Manta, S.; Agelis, G.; Botic´, T.; Cencicˇ, A.; Komiotis, D. Fluoro-ketopyranosyl nucleosides: Synthesis
and biological evaluation of 3-fluoro-2-keto-β-d-glucopyranosyl derivatives of N 4-benzoyl cytosine.
Bioorg. Med. Chem. 2007, 15, 980–987.
26. Manta, S.; Agelis, G.; Botic´, T.; Cencicˇ, A.; Komiotis, D. Unsaturated fluoro-ketopyranosyl nucleosides:
Synthesis and biological evaluation of 3-fluoro-4-keto-β-d-glucopyranosyl derivatives of N 4-benzoyl
cytosine and N 6-benzoyl adenine. Eur. J. Med. Chem. 2008, 43, 420–428.
27. Manta, S.; Tzioumaki, N.; Tsoukala, E.; Panagiotopoulou, A.; Pelecanou, M.; Balzarini, J.; Komiotis, D.
Unsaturated dideoxy fluoro-ketopyranosyl nucleosides as potent antitumor agents: A convenient syn-
thesis of 2,6-dideoxy-3-fluoro-4-keto-β-d-glucopyranosyl analogues of uracil, 5-fluorouracil, thymine,
N 4-benzoyl cytosine and N 6-benzoyl adenine. Eur. J. Med. Chem. 2009, 44, 4764–4771.
28. Manta, S.; Tsoukala, E.; Tzioumaki, N.; Goropevˇsek, A.; Pamulapati, R.T.; Cencicˇ, A.; Balzarini J.;
Komiotis, D. Dideoxy fluoro-ketopyranosyl nucleosides as potent antiviral agents: Synthesis and
biological evaluation of 2,3- and 3,4-dideoxy-3-fluoro 4- and -2-keto-β-d-glucopyranosyl derivatives of
N 4-benzoyl cytosine. Eur. J. Med. Chem. 2009, 44, 2696–2704.
29. Manta, S.; Tsoukala, E.; Tzioumaki, N.; Kiritsis, C.; Balzarini, J.; Komiotis, D. Synthesis of 4,6-dideoxy-
3-fluoro-2-keto-β-d-glucopyranosyl analogues of 5-fluorouracil, N 6-benzoyl adenine, uracil, thymine
and N 4-benzoyl cytosine and evaluation of their antitumor activities. Bioorg. Chem. 2010, 38, 48–55.
30. Tsoukala, E.; Manta, S.; Tzioumaki, N.; Kiritsis, C.; Komiotis, D. Keto-fluorothiopyranosyl nucleosides:
A convenient synthesis of 2- and 4-keto-3-fluoro-5-thioxylopyranosyl thymine analogs. Carbohydr. Res.
2011, 346, 2011–2015.
31. Agelis, G.; Tzioumaki, N.; Botic´, T.; Cencicˇ, A.; Komiotis, D. Exomethylene pyranonucleosides:
Efficient synthesis and biological evaluation of 1-(2,3,4-trideoxy-2-methylene-β-d-glycero-hex-3-
enopyranosyl)thymine. Bioorg. Med. Chem. 2007, 15, 5448–5456.
32. Agelis, G.; Tzioumaki, N.; Tselios, T.; Botic´, T.; Cencicˇ, A.; Komiotis, D. Exomethylene pyranonucle-
osides: Synthesis, conformational analysis and biological evaluation of 1-(2,3,4-trideoxy-4-methylene-
α-d-glycero-hex-2-enopyranosyl)uracile. Eur. J. Med. Chem. 2008, 43, 1366–1375.
33. Kiritsis, C.; Manta, S.; Parmenopoulou, V.; Balzarini, J.; Komiotis, D. Branched-chain C-cyano pyra-
nonucleosides: Synthesis of 3ꢁ-C-cyano & 3ꢁ-C-cyano-3ꢁ-deoxy pyrimidine pyranonucleosides as novel
cytotoxic agents. Eur. J. Med. Chem. 2011, 46, 5668–5674.
34. Kiritsis, C.; Manta, S.; Papasotiriou, I.; Coutouli-Argyropoulou, E.; Trakossas, S.; Balzarini, J.; Komi-
otis, D. Synthesis and biological evaluation of 3ꢁ-C-ethynyl and 3ꢁ-C-(1,4-disubstituted-1,2,3-triazolo)
double-headed pyranonucleosides. Med. Chem., 2012, 8, 320–329.
35. Tzioumaki, N.; Manta, S.; Tsoukala, E.; Vande Voorde, J.; Liekens, S.; Komiotis, D.; Balzarini, J. Syn-
thesis and biological evaluation of unsaturated keto and exomethylene d-arabinopyranonucleoside
analogs: Novel 5-fluorouracil analogs that target thymidylate synthase. Eur. J. Med. Chem. 2011, 46,
993–1005.
36. Balatsos, N.A.; Vlachakis, D.; Maragozidis, P.; Manta, S.; Anastasakis, D.; Kyritsis, A.; Vlassi, M.; Komi-
otis, D.; Stathopoulos, C. Competitive inhibition of human poly(A)-specific ribonuclease (PARN) by
synthetic fluoro-pyranosyl nucleosides. Biochemistry 2009, 48, 6044–6051.
37. Tsirkone, V.G.; Tsoukala, E.; Lamprakis, C.; Manta, S.; Hayes, J.M.; Skamnaki, V.T.; Drakou, C.;
Zographos, S.E.; Komiotis, D.; Leonidas, D.D. 1-(3-Deoxy-3-fluoro-beta-d-glucopyranosyl) pyrimidine
derivatives as inhibitors of glycogen phosphorylase b: Kinetic, crystallographic and modelling studies.
Bioorg. Med. Chem. 2010, 18, 3413–3425.
38. Jain, R.; Kamau, M.; Wang, C.; Ippolito, R.; Wang, H.; Dulina, R.; Anderson, J.; Gange, D.; Sofia,
M.J. 3-azido-3-deoxy-glycopyranoside derivatives as scaffolds for the synthesis of carbohydrate-based
universal pharmacophore mapping libraries. Bioorg. Med. Chem. Lett. 2003, 13, 2185–2189.
39. Tsoukala, E.; Agelis, G.; Dolinsek, J.; Botic´, T.; Cencicˇ, A.; Komiotis, D. An efficient synthesis of 3-
fluoro-5-thio-xylofuranosyl nucleosides of thymine, uracil, and 5-fluorouracil as potential antitumor
or/and antiviral agents. Bioorg. Med. Chem. 2007, 15, 3241–3247.
40. Brimacombe, J.S.; Bryan, J.G.H.; Husain, A.; Stacey, M.; Tolley, M.S. The oxidation of some carbohy-
drate derivatives, using acid anhydride-methyl sulphoxide mixtures and the pfitzner-moffatt reagent.
Facile synthesis of 3-acetamido-3-deoxy-d-glucose and 3-amino-3-deoxy-d-xylose. Carbohydr. Res. 1967,
3, 318–324.
41. Vuilhorgne, M.; Ennifar, S.; Das, C.B. Synthesis and conformational study by 13C NMR of β-pyrimidine
nucleosides containing one or two hexopyranosyl subunits: Application to the Anthelmycin confor-
mation. Carbohydr. Res. 1981, 97, 19–30.

Stereocontrolled Facile Synthesis of Amino and Azido Pyranonucleosides
535
42. Vorbruggen, H.; Hoefle, G. Nucleoside syntheses. XXIII. On the mechanism of nucleoside synthesis.
Chem. Ber. 1981, 114, 1256–1268.
43. Vanheusden, V.; Busson, R.; Herdewijn, P.; Van Calenbergh, S. Synthesis and conformational
analysis of 1-[2,4-dideoxy-4-C-hydroxymethyl-alpha-l-lyxopyranosyl]thymine. J. Org. Chem. 2004, 69,
4446–4453.
44. Hanessian, S.; Vate`le, J.M. Design and reactivity of organic functional groups: Imidazolylsulfonate
(imidazylate)—An efficient and versatile leaving group. Tetrahedron Lett. 1981, 22, 3579–3582.
45. Wolfrom, M.L.; Bernsmann, J.; Horton, D. Synthesis of amino sugars by reduction of hydrazine
derivatives. 5-amino-3,6-anhydro-5-deoxy-l-idose derivatives. J. Org. Chem. 1962, 27, 4505–4509.
46. Worch, M.; Wittmann, V. Unexpected formation of complex bridged tetrazoles via intramolecular
1,3-dipolar cycloaddition of 1,2-O-cyanoalkylidene derivatives of 3-azido-3-deoxy-d-allose. Carbohydr.
Res. 2008, 343, 2118–2129.
47. Baer, H.H; Gan, Y. Synthesis of the methyl 3-amino-3-deoxy-α- and β-d-allopyranosides and
-allofuranosides. Carbohydr. Res. 1991, 210, 233–245.