Design, synthesis, antiviral and cytostatic activity of ω-(1H-1,2,3-triazol-1-yl)(polyhydroxy)alkylphosphonates as acyclic nucleotide analogues

Article abstract of DOI:10.1016/j.bmc.2014.05.020

The efficient synthesis of a new series of polyhydroxylated dibenzyl ω-(1H-1,2,3-triazol-1-yl)alkylphosphonates as acyclic nucleotide analogues is described starting from dibenzyl ω-azido(polyhydroxy)alkylphosphonates and selected alkynes under microwave irradiation. Selected O,O- dibenzylphosphonate acyclonucleotides were transformed into the respective phosphonic acids. All compounds were evaluated in vitro for activity against a broad variety of DNA and RNA viruses and for cytostatic activity against murine leukemia L1210, human T-lymphocyte CEM and human cervix carcinoma HeLa cells. Compound (1S,2S)-16b exhibited antiviral activity against Influenza A H3N2 subtype (EC₅₀ = 20 μM - visual CPE score; EC₅₀ = 18 μM - MTS method; MCC >100 μM, CC₅₀ >100 μM) in Madin Darby canine kidney cell cultures (MDCK), and (1S,2S)-16k was active against vesicular stomatitis virus and respiratory syncytial virus in HeLa cells (EC₅₀ = 9 and 12 μM, respectively). Moreover, compound (1R,2S)-16l showed activity against both herpes simplex viruses (HSV-1, HSV-2) in HEL cell cultures (EC₅₀ = 2.9 and 4 μM, respectively) and feline herpes virus in CRFK cells (EC₅₀ = 4 μM) but at the same time it exhibited cytotoxicity toward uninfected cell (MCC ≥ 4 μM). Several other compounds have been found to inhibit proliferation of L1210, CEM as well as HeLa cells with IC₅₀ in the 4-50 μM range. Among them compounds (1S,2S)- and (1R,2S)-16l were the most active (IC₅₀ in the 4-7 μM range).

Full text of DOI:10.1016/j.bmc.2014.05.020

Bioorganic & Medicinal Chemistry xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
Bioorganic & Medicinal Chemistry
journal homepage: www.elsevier.com/locate/bmc
Design, synthesis, antiviral and cytostatic activity of
x
-(1H-1,2,3-triazol-1-yl)(polyhydroxy)alkylphosphonates as
acyclic nucleotide analogues
b
b
b
b
Iwona E. Głowacka a, , Jan Balzarini , Graciela Andrei , Robert Snoeck , Dominique Schols ,
⇑
Dorota G. Piotrowska a
a
´
´
´
Bioorganic Chemistry Laboratory, Faculty of Pharmacy, Medical University of Łódz, Muszynskiego 1, 90-151 Łódz, Poland
b Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
a r t i c l e i n f o
a b s t r a c t
Article history:
The efficient synthesis of
yl)alkylphosphonates as acyclic nucleotide analogues is described starting from dibenzyl
a
new series of polyhydroxylated dibenzyl
x
-(1H-1,2,3-triazol-1-
-azido-
Received 11 February 2014
Revised 12 May 2014
Accepted 12 May 2014
Available online xxxx
x
(polyhydroxy)alkylphosphonates and selected alkynes under microwave irradiation. Selected
O,O-dibenzylphosphonate acyclonucleotides were transformed into the respective phosphonic acids.
All compounds were evaluated in vitro for activity against a broad variety of DNA and RNA viruses
and for cytostatic activity against murine leukemia L1210, human T-lymphocyte CEM and human cervix
carcinoma HeLa cells. Compound (1S,2S)-16b exhibited antiviral activity against Influenza A H3N2
Keywords:
Cycloaddition
1,2,3-Triazoles
Phosphonates
Nucleotide analogues
Antiviral
subtype (EC50 = 20
Madin Darby canine kidney cell cultures (MDCK), and (1S,2S)-16k was active against vesicular stomatitis
virus and respiratory syncytial virus in HeLa cells (EC50 = 9 and 12 M, respectively). Moreover,
compound (1R,2S)-16l showed activity against both herpes simplex viruses (HSV-1, HSV-2) in HEL cell
cultures (EC50 = 2.9 and 4 M, respectively) and feline herpes virus in CRFK cells (EC50 = 4 M) but at
the same time it exhibited cytotoxicity toward uninfected cell (MCC P 4 M). Several other compounds
have been found to inhibit proliferation of L1210, CEM as well as HeLa cells with IC50 in the 4–50
range. Among them compounds (1S,2S)- and (1R,2S)-16l were the most active (IC50 in the 4–7 M range).
lM—visual CPE score; EC50 = 18 lM—MTS method; MCC >100 lM, CC50 >100 lM) in
l
Cytostatic
l
l
l
l
M
l
Ó 2014 Elsevier Ltd. All rights reserved.
1. Introduction
Attempts to improve the solubility of compounds in aqueous
media resulted in synthesis of hydroxylated analogues of nucleo-
sides such as ganciclovir as well as other nucleoside mimetics
shown on Figure 1.4,6–14 The interest in investigation of hydroxyl-
ated nucleosides has also been stimulated by a previous discovery
Infectious diseases caused by different microorganisms such as
bacteria, fungi and viruses, are still a problem of human civilization.
Among all pathogenic microorganisms viruses are notorious, the
most active and probably the most dangerous because they pene-
trate into cells, evolve rapidly and interfere with the genetic mate-
rial of the host. Despite current achievements in the development of
antiviral drugs,1,2 there is still a need for new compounds with an
unique mechanism of action and limited side-effects.
The successful search for acyclic nucleoside analogues
started when acyclovir [9-(2-hydroxyethoxymethyl)guanine] was
described as an antiherpesvirus agent.3 Soon after, a few other acy-
clic nucleoside or acyclic nucleoside phosphonate analogues
became available as antiviral compounds, namely, ganciclovir,
cidofovir, tenofovir, adefovir, etc.4,5
of extreme potency of the naturally accessible
which acts as an inhibitor of S-adenosyl- -homocysteine hydrolase
D
-eritadenine 2,7,8
L
(SAHH). This enzyme has earlier been shown to be an attractive
target for poxviruses, (ꢀ)RNA viruses such as paramyxovirus and
rhabdovirus, and ( )RNA viruses such as reovirus.15,16 Conse-
quently, (20S)-9-(20,30-dihydroxypropyl)adenine 310 and other
N(9)-substituted adenines and guanines possessing poly-
hydroxyalkyl chains have been obtained (Fig. 1).
Among various structural modifications of nucleosides/nucleo-
tides 1,2,3-triazole analogues have been of special interest. The
applicability of a 1,2,3-triazole ring as a replacement of sugar17–19
or nucleobase moieties17,19–21 as well as an additional linker
between a phosphonoalkyl unit and a nucleobase has been widely
explored22–28 including our achievements.29–35 Recently, several
⇑
Corresponding author. Tel.: +48 42 677 9237; fax: +48 42 678 8398.
E-mail address: iwona.glowacka@umed.lodz.pl (I.E. Głowacka).
http://dx.doi.org/10.1016/j.bmc.2014.05.020
0968-0896/Ó 2014 Elsevier Ltd. All rights reserved.
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

2
I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
NH2
NH2
B
NH2
NH2
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
OH
O
N
N
N
H
HO
HO
N
N
H
HO
N
H
B
OH
N
H
H
H
H
H
OH
OH
(BnO)2(O)P
(BnO)2(O)P
OH
OH
OH
O
OBn
COOH
(R)-1
COOH
(2R,3R)-2
B = natural or modified nucleobase
(2S,3R)-4
(2S)-3
(1S,2R,3S)-17
(1S,2R,3R)-17
(1S,2S)-16
(1R,2S)-16
O
N
NH2
NH2
N
NH2
N
N
N
N
N
N
N
N
HN
H2N
N
HN
Figure 3. Structures of the designed nucleotide phosphonate analogues 16 and 17.
N
N
N
OH
HO
O
analogous compounds having unfunctionalised aliphatic
moieties.33
OH OH
OH
OH
OH
OH
5
7
8
6
2. Results and discussion
Figure 1. Examples of hydroxylated nucleoside analogues.
2.1. Chemistry
acyclic 1,2,3-triazolyl analogues of nucleosides/nucleotides with
nucleobases attached via the methylene group at the C4 in the
1,2,3-triazole moiety have been obtained and some of them
showed promising biological activity (Fig. 2). While (1,2,3-tria-
zol-1-yl)nucleosides 9–11 were found to be inactive against
selected viruses,22,23 the phosphonomethyl-12 (n = 1; B = Thy,
Ade) and phosphonoethyl(1,2,3-triazoles) 12 (n = 2; R = Thy, Ura)
Enantiomerically pure (1R,2S)- and (1S,2S)-azidophosphonates
18 were obtained from
L
-ascorbic acid,36,37 whereas for the synthe-
sis of (1S,2R,3S)- and (1S,2R,3R)-azidophosphonates 1938 tartaric
acid and
chirality.
L-isoascorbic acid were used, respectively, as a source of
The 1,2,3-triazoles (1R,2S)- and (1S,2S)-16 were synthesised by
the 1,3-dipolar cycloaddition of the corresponding (1R,2S)- and
(1S,2S)-azidophosphonates 18 with N-propargyl nucleobases 20
(N9-propargyladenine 20a,23 N1-propargylthymine 20b,23 N1-propar-
gyluracil 20c,39 N4-acetyl-N1-propargylcytosine 20d40) and several
propargylated nucleobase mimetics 20 (N1-propargyl-6-azauracil
20e,41 3-acetyl-N-propargylindole 20f,42 N1-propargyltheobromine
20g,43,44 N7-propargyltheophylline 20h,45 8-chloro-N7-propargylthe-
ophylline 20i,46 N-propargyl-2-pyridone 20j,47 N3-benzoyl-N1-prop-
argyluracil 20k33,48 and N3-benzoyl-N1-propargylquinazolin-2,4-
dione 20l33).
According to a standard protocol the regioselective formation of
respective 1,4-disubstituted 1,2,3-triazoles was secured by the
1,3-dipolar cycloaddition of azides with terminal alkynes in the
presence of a catalytic amount of Cu(I) at room temperature.49,50
However, under these conditions more than 3 days were required
to complete the reaction of (1S,2S)- and (1R,2S)-azidophosphonates
18 with N-propargyl nucleobases 20. To accelerate the reaction
showed moderate activity against hepatitis
C
virus (HCV).25
Recently, we succeeded in the synthesis of 1-(3-phosphonopro-
pyl)-1,2,3-triazole 13 substituted with benzoylbenzuracil via a
methylene linker which exhibited activity against herpes simplex
virus-1 (KOS), herpes simplex virus-2 (G) and feline herpes virus.33
Moreover, the 1-(3-amino-3-phosphonopropyl)-1,2,3-triazole ana-
logue (R)-14 having 3-acetylindole as a modified nucleobase
showed moderate activity toward vesicular stomatitis virus.35
In continuation of our research program towards 1,2,3-triazole
nucleoside analogues,14–21 and taking into account the known bio-
logical activity of hydroxylated nucleoside analogues as well as the
antiviral activity of 13 and 14 and the cytostatic properties of 15,
1,2,3-triazoles 16 and 17 possessing dibenzyloxyphosphono(poly-
hydroxy)alkyl residues have been designed (Fig. 3). We assumed
that incorporation of additional hydroxyl groups into an alkyl
side-chain would assure better solubility and perhaps improve bio-
logical activity of 1,2,3-triazoles 16 and 17 in comparison with
O
N
OCH3
I
NH
N
N
N
N
O
B = Ade, Thy,
B
Ura, 6-AzaUra,
SCH2C6H5
N
N
N
N
N
N
O
N
O
N
N
N
N
N
N
HO
HO
HO
11
9
10
O
O
Ac
Ac
N
Ph
O
N
N
N
N
B
N
N
N
N
(EtO)2(O)P
N
(EtO)2(O)P
N
(EtO)2(O)P
N
N
(HO)2(O)P
n = 1, 2
N
N
N
X
n
NHBoc
12
13
14
15
X = CH2, (CH2)2, (CH2)3,
(CH2)4, CH(OH)CH2
B = Ura, Thy,Ade
Figure 2. Examples of known 1,2,3-triazolyl analogues of nucleosides/nucleotides.
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
3
varicella-zoster virus (TK+ VZV strain OKA and TKꢀ VZV strain 07-1);
(b) CEM cell cultures: human immunodeficiency virus [HIV-1
and HIV-2]; (c): Vero cell cultures: para-influenza-3 virus, reovi-
rus-1, Sindbis virus, Coxsackie virus B4, Punta Toro virus; (d) HeLa
cell cultures: vesicular stomatitis virus, Coxsackie virus B4 and
respiratory syncytial virus (RSV); (e) Crandell-Rees Feline Kidney
(CRFK) cell cultures: feline corona virus (FIPV) and feline herpes
virus (FHV); (f) Madin Darby Canine Kidney (MDCK) cell cultures:
influenza A virus H1N1 subtype (A/PR/8), influenza A virus H3N2
subtype (A/HK/7/87) and influenza B virus (B/HK/5/72). Ganciclo-
vir, cidofovir, acyclovir, brivudin, (S)-9-(2,3-dihydroxypropyl)ade-
nine [(S)-DHPA], Hippeastrum hybrid agglutinin (HHA), Urtica
dioica agglutinin (UDA), dextran sulfate (molecular weight 5000,
DS-5000), ribavirin, oseltamivir carboxylate, amantadine and
rimantadine were used as the reference compounds. The antiviral
activity was expressed as the EC50: the compound concentration
required to reduce virus plaque formation (VZV) by 50% or to
reduce virus-induced cytopathogenicity by 50% (other viruses).
The cytotoxicity of the tested compounds toward the unin-
fected host cells was defined as the minimum cytotoxic concentra-
tion (MCC) that causes a microscopically detectable alteration of
normal cell morphology. The 50% cytotoxic concentration (CC50),
causing a 50% decrease in cell viability was determined using a col-
orimetric 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphe-
nyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay system.
B
N
N
OH
OH
N
B
a
(BnO)2(O)P
N3
(BnO)2(O)P
OBn
OBn
(1S,2S)-16
(1S,2S)-18
(1R,2S)-18
20
(1R,2S)-16
NHAc
O
N
c
Ac
NH2
N
O
O
N
e
H3C
N
N
N
NH
O
NH
O
N
NH
O
B =
N
N
N
N
O
b
d
f
a
O
CH3
N
N
CH3
CH3
O
O
N
k
O
N
O
N
N
NBz
O
N
N
N
N
NBz
O
Cl
N
O
N
N
N
N
O
CH3
CH3
CH3
O
O
h
l
i
g
j
Scheme 1. Reagents and conditions: (a) CuSO4 ꢁ 5H2O (0.05 equiv), sodium
ascorbate (0.1 equiv), H2OꢂEtOH (1:1), MW, 40–45 °C, 20 min.
the 1,3-dipolar cycloaddition was performed under microwave
irradiation. Under these conditions the full conversion of
azidophosphonates 18 into 1,2,3-triazoles 16 was observed at
40–45 °C within 20 min (Scheme 1).
In a similar way, employing (1S,2R,3S)- and (1S,2R,3R)-azi-
dophosphonates 19 the corresponding 1,2,3-triazoles (1S,2R,3S)-
and (1S,2R,3R)-17 were successfully obtained (Scheme 2).
The compounds (1R,2S)- and (1S,2S)-16 as well as (1S,2R,3S)-
and (1S,2R,3R)-17 were obtained in good yields after purification
by column chromatography on silica gel.
It was established that compound (1S,2S)-16b containing a
1,2,3-triazole moiety substituted at C40 with thymine exhibited
antiviral activity against Influenza A H3N2 subtype (EC50 = 20
lM
by visual CPE score; EC50 = 18 M by MTS score; MCC >100 lM,
l
CC50 >100 lM) in Madin Darby canine kidney cells (MDCK). On
the other hand, compound (1S,2S)-16k with N3-benzoyluracil
showed antiviral activity against vesicular stomatitis virus
(EC50 = 9
lM) and respiratory syncytial virus (EC50 = 12 lM) in
Selected dibenzyl phosphonates (1S,2S)-16 were subjected to
hydrogenation in the presence of 10% Pd–C in aqueous methanol37
to give the respective phosphonic acids 21 in good yields
(Scheme 3).
HeLa cells which favourably compares with the data for ribavirin
(EC50 = 17 and 5 lM, respectively). Moreover, compound (1R,2S)-
16l containing the N3-benzoylbenzuracil moiety showed activity
against both herpes simplex viruses (HSV-1, HSV-2) in HEL cell cul-
Structures of all new compounds were confirmed on the basis of
1H, 13C, 31P NMR and IR spectra data as well as by elemental
analysis.
tures (EC50 = 2.9 and 4
CRFK cells (EC50 = 4 M) but at the same time it exhibited cytotox-
icity toward uninfected cell cultures (MCC P 4 M). Moreover,
compound (1S,2S)-16e was slightly active against both TK+ VZV
and TK VZV strains (EC50 = 63.7 and 70 M, respectively), whereas
(1S,2R,3R)-17i showed activity against the TK+ VZV strain only
(EC50 = 55.7 M).
lM, respectively) and feline herpes virus in
l
l
2.2. Antiviral activity and cytotoxicity evaluation
l
All the synthesised phosphonates (1R,2S)- and (1S,2S)-16 and
(1S,2R,3S)- and (1S,2R,3R)-17 as well as the phosphonic acids
(1S,2S)-21b and (1S,2S)-21k were evaluated for their antiviral
activities against a wide variety of DNA and RNA viruses, using
the following cell-based assays: (a) human embryonic lung (HEL)
cells: herpes simplex virus-1 (KOS), herpes simplex virus-2 (G),
herpes simplex virus-1 (TK ACVr KOS), vaccinia virus and vesicular
stomatitis virus, cytomegalovirus (AD-169 strain and Davis strain),
l
2.3. Evaluation of cytostatic activity
The cytostatic activity of the tested compounds was defined as
the 50% cytostatic inhibitory concentration (IC50), causing a 50%
decrease in cell proliferation and was determined against murine
N
OH
O
OH
O
N
N
B
B
N3
a
(BnO)2(O)P
(BnO)2(O)P
O
O
20
(1S,2R,3S)-19
(1S,2R,3R)-19
(1S,2R,3S)-17
(1S,2R,3R)-17
O
N
CH3
N
N
CH3
CH3
NHAc
N
O
N
c
NH2
N
N
O
N
b
O
N
O
H3C
N
N
N
N
N
N
N
N
NH
O
NH
O
B =
Cl
N
N
O
N
O
CH3
CH3
CH3
O
O
h
i
d
g
a
Scheme 2. Reagents and conditions: (a) CuSO4 ꢁ 5H2O (0.05 equiv), sodium ascorbate (0.1 equiv), H2OꢂEtOH (1:1), MW, 40–45 °C, 20 min.
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

4
I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
Table 1
B
B
Inhibitory effect of tested compounds against the proliferation of murine leukemia
(L1210), human T-lymphocyte (CEM) and human cervix carcinoma cells (HeLa)
N
N
N
N
OH
N
OH
N
a
Compound
Nucleobase (B)
IC50
(
lM)
a
(BnO)2(O)P
(HO)2(O)P
CEM
L1210
HeLa
OBn
OH
(1S,2S)-16a
(1S,2S)-16b
(1S,2S)-16c
(1S,2S)-16d
(1S,2S)-16e
(1S,2S)-16f
(1S,2S)-16g
(1S,2S)-16h
(1S,2S)-16i
(1S,2S)-16j
(1S,2S)-16k
(1S,2S)-16l
(1S,2S)-21b
(1S,2S)-21k
(1R,2S)-16a
(1R,2S)-16b
(1R,2S)-16c
(1R,2S)-16d
(1R,2S)-16e
(1R,2S)-16f
(1R,2S)-16g
(1R,2S)-16h
(1R,2S)-16i
(1R,2S)-16j
(1R,2S)-16k
(1R,2S)-16l
Adenine
Thymine
Uracil
78 15
>200
>200
169 9.9 153 35
71 11
>200
66 6.4
>200
>200
81 21
>200
>200
>200
64 18
>200
78 17
79 0.7
>200
45 2.1
76 21
7.1 4.3
>200
(1S,2S)-16
(1S,2S)-21
O
N
b
O
N
k
N4-Acetylcytosine
6-Azauracil
3-Acetylindole
Theobromine
Theophylline
H3C
NH
O
NBz
O
B =
78 7.8
>200
82 0.7
71 0.7
71 8.5
71 9.2
70 42
63 22
26 12
4.1 1.8
>200
8-Chlorotheophylline 27 2.1
Scheme 3. Reagents and conditions: (a) H2, 10% Pd–C, MeOHꢂH2O, 24 h.
2-Pyridon
90 0.7
21
N3-Benzoyluracil
2
N3-Benzoylbenzuracil 4.7 0.6
leukaemia L1210, human lymphocyte CEM and human cervix car-
cinoma HeLa cells.
Thymine
>200
>200
N3-Benzoyluracil
Adenine
>200
>200
The inhibitory effect of the series of dibenzyl (1H-1,2,3-triazol-
1-yl)alkylphosphonates against the proliferation of murine leuke-
mia (L1210), human T-lymphocyte (CEM) and human cervix
carcinoma cells (HeLa) are shown in Table 1. Several compounds
were endowed with a cytostatic activity at compound concentra-
76 11
83 2.8
91 6.4
82 3.5
81 2.8
16 3.5
68 6.4
72 9.9
46 40
85 9.9
86 18
96 11
71 13
15 4.2
58 15
56 13
22 0.7
80 6.4
64 25
66 12
160 57
122 35
13 2.8
76 9.2
83 9.9
86 4.2
28 19
57 33
5.1 3.2
>200
Thymine
Uracil
N4-Acetylcytosine
6-Azauracil
3-Acetylindole
Theobromine
Theophylline
tions below 50 lM [i.e., (1S,2S)-16i–l and (1R,2S)-16f–l] toward
tested tumor cell lines, namely, L1210,CEM and HeLa. Among
all tested compounds, 1,2-dihydroxypropylphosphonates (1S,2S)-
and (1R,2S)-16l, both having N3-benzoylbenzuracil as a modified
nucleobase, were the most potent and showed cytostatic activity
8-Chlorotheophylline 25 1.4
2-Pyridon
101 6.4 76 2.8
21 21
N3-Benzoyluracil
1
1
N3-Benzoylbenzuracil 4.7 0.1
4.7 0.3
>200
139 46
>200
(1S,2R,3S)-17a Adenine
>200
>200
>200
>200
142 40 145
>200
between 4 and 7 lM toward the tested tumor cell lines (Table 1).
(1S,2R,3S)-17b Thymine
(1S,2R,3S)-17c Uracil
107 37
118 16
>200
>200
>200
2.3.1. Structure–activity relationship studies
(1S,2R,3S)-17d N4-Acetylcytosine
(1S,2R,3S)-17g Theobromine
>200
As far as cytostatic properties are considered, within a series of
hydroxylated (1,2,3-triazol-1-yl)nucleotide analogues 16 and 17,
compounds 16 containing three-carbon phosphonoalkyl chain are
more cytostatic toward the tested tumor cell lines when compared
with four-carbon phosphonates 17 having the same nucleobases
(16a vs 17a, 16c vs 17c, 16d vs 17d, 16g vs 17g, 16i vs 17i). Moreover,
the configurations at stereogenic centres have slight or negligible
impact on the cytostatic properties of (1,2,3-triazol-1-yl)nucleo-
tides [(1S,2S)-16 vs (1R,2S)-16 and (1S,2R,3S)-17 vs (1S,2R,3R)-
17)]. Among the series of 1,2-dihydroxypropylphosphonates 16,
both stereoisomers substituted with the N3-benzoylbenzuracil moi-
ety [(1S,2S)-16l and (1R,2S)-16l] were the most potent to inhibit the
proliferation of L1210, CEM as well as HeLa cells, whereas their
N3-benzoyluracil counterparts (1S,2S)-16k and (1R,2S)-16k showed
significantly lower inhibitory activity. The removal of the N3-ben-
zoyl group from uracil resulted in complete loss of activity for
(1S,2S)-16c and further decrease in potency for (1R,2S)-16c. Func-
tionalisation of the alkyl chains in the analogues equipped with
the N3-benzoylbenzuracil moiety significantly improved cytostatic
activity of 1-hydroxy-2-benzyloxypropylphosphonates (1S,2S)-16l
and (1R,2S)-16l when compared with the slightly active 1-hydroxy-
propyl- and 2-hydroxypropylphosphonates33 and the inactive pro-
pylphosphonate 13.33 As could be expected highly polar
phosphonic acid (1S,2S)-21k showed no cytostatic activity while
much more lipophilic O,O-dibenzyl ester (1S,2S)-16k was moder-
ately active.
0
(1S,2R,3S)-17i
8-Chlorotheophylline >200
(1S,2R,3R)-17a Adenine
(1S,2R,3R)-17b Thymine
(1S,2R,3R)-17c Uracil
140 49 98 3.5
P167
P200
>200
>200
>200
>200
>200
>200
>200
122 21
>200
>200
(1S,2R,3R)-17d N4-Acetylcytosine
(1S,2R,3R)-17g Theobromine
(1S,2R,3R)-17h Theophylline
115 4.2 86 2.1
>200
>200
(1S,2R,3R)-17i
5-Fluorouracil
8-Chlorotheophylline 51 1.4
18
58 9.9
0.33 0.17 0.54 0.12
85 3.5
5
a
50% Inhibitory concentration or compound concentration required to inhibit
tumor cell proliferation by 50%.
(1,2,3-triazol-1-yl)nucleotides having an unsubstituted phospho-
nopropyl chain, since compound 13 was the most active against
HSV-1, HSV-2 (EC50 = 17
lM) and against feline herpes virus
(EC50 = 24
l
M).33 Furthermore, the stereochemistry of the aliphatic
chain substituted with hydroxyl groups is essential for activity
since analogue (1S,2S)-16l showed no activity. On the other hand,
the significant activity toward vesicular stomatitis virus and respi-
ratory syncytial virus in HeLa cell cultures was observed for com-
pound (1S,2S)-16k containing an N3-benzoyluracil unit (EC50 = 9
and 12 lM, respectively) since analogous compounds (1S,2S)-16l
(B = N3-benzoylbenzuracil) and (1S,2S)-16c (B = uracil) were inac-
tive against these viruses. Again, stereochemistry of an aliphatic
fragment appeared important and resulted in lack of activity for
(1R,2S)-16k.
Analogous structure–antiviral activity relationship studies on a
series of (1,2,3-triazol-1-yl)nucleotide analogues 16 and 17 were
performed.
(1R,2S)-16l, which contains
showed promising antiviral activity against herpes simplex viruses
(HSV-1, HSV-2) in HEL cell cultures (EC50 = 2.9 and 4 M, respec-
M), whereas
Thus,
1-hydroxy-2-benzyloxypropylphosphonate
3. Conclusions
a
N3-benzoylbenzyuracil residue,
Dibenzyl
x-(1H-1,2,3-triazol-1-yl)alkylphosphonates (1S,2S)-
l
and (1R,2S)-16 as well as (1S,2R,3S)-17 and (1S,2R,3R)-17 were
efficiently synthesised as acyclic nucleotide analogues. The
phosphonic acids (1S,2S)-21b and (1S,2S)-21k were synthesised
from O,O-dibenzylphosphonate acyclonucleotides (1S,2S)-16b and
(1S,2S)-16k by hydrogenolysis. All synthesised esters and acids
tively) and feline herpes virus in CRFK cells (EC50 = 4
l
its N3-benzoyluracil and uracil analogues (1R,2S)-16k and
(1R,2S)-16c, respectively, appeared inactive. This trend well corre-
lates with our previous observations on structurally analogous
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
5
were tested in vitro for activity against a broad variety of DNA and
RNA viruses and for cytostatic activity against murine leukemia
L1210, human T-lymphocyte CEM and human cervix carcinoma
HeLa cells. Antiviral activity against Influenza A H3N2 subtype
(m, 10H, Haromat), 7.19–7.11 (m, 3H, Haromat), 7.06–6.98 (m, 2H,
Haromat), 6.16 (br s, 2H, NH2), 5.37 (AB, J = 15.3 Hz, 1H, CHaHb-
Ade), 5.32 (AB, J = 15.3 Hz, 1H, CHaHb-Ade), 5.03 (d, J = 7.8 Hz, 4H,
2ꢁPOCH2Ph), 4.61 (dd, J = 14.1 Hz, J = 5.1 Hz, 1H, H-3a), 4.54 (d,
J = 10.8 Hz, 1H, OCHaHbPh), 4.47 (dd, J = 14.1 Hz, J = 7.2 Hz, 1H,
H-3b), 4.25 (dddd, J = 7.8 Hz, J = 7.2 Hz, J = 5.1 Hz, J = 3.0 Hz, 1H,
H-2), 4.15 (d, J = 10.8 Hz, 1H, OCHaHbPh), 3.96 (dd, J = 11.1 Hz,
J = 3.0 Hz, 1H, H-1), 2.16 (br s, 1H, OH); 13C NMR (151 Hz, DMSO-
d6): d = 156.4, 153.0, 149.8, 143.0, 141.0, 137.9, 137.1 (d,
J = 6.2 Hz, Cipso), 137.0 (d, J = 6.2 Hz, Cipso), 129.3, 129.0, 128.9,
128.8, 128.7, 128.4, 128.3, 128.2, 128.1, 127.5, 125.1, 119.1, 78.7
(d, J = 3.3 Hz, C-2), 73.0, 68.0 (d, J = 6.5 Hz, POC), 67.8 (d,
J = 162.2 Hz, PC), 67.3 (d, J = 6.5 Hz, POC), 50.9 (d, J = 10.0 Hz, C-
3), 38.4; 31P NMR (121.5 MHz, CDCl3): d = 23.49 ppm. Anal. Calcd
for C32H33N8O5P: C, 59.99; H, 5.19; N, 17.49. Found: C, 60.12; H,
5.19; N, 17.21.
(EC50 = 20
l
M—visual CPE score; EC50 = 18
lM—MTS; MCC
>100 M, CC50 >100
l
l
M) in Madin Darby canine kidney cell cul-
tures (MDCK) has been observed for phosphonate (1S,2S)-16b,
whereas (1S,2S)-16k was found active against vesicular stomatitis
virus and respiratory syncytial virus in HeLa cell cultures (EC50 = 9
and 12
16f–l inhibited proliferation of L1210, CEM as well as HeLa cells
with IC50’s in the 4–50 M range. Especially, (1S,2S)- and (1R,2S)-
16l consistently inhibited tumor cell proliferation in the lower
lM, respectively). Compounds (1S,2S)-16i–l and (1R,2S)-
l
micromolar range (IC50 = 4–7
the tumor cell line.
lM), irrespective of the nature of
4. Experimental section
4.2.2. (1S,2S)-Dibenzyl 2-benzyloxy-3-{4-[(5-methyl-2,4-
dioxopyrimidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1S,2S)-16b
1H NMR were taken in CDCl3 or CD3OD on the following spec-
trometers: Varian Mercury-300 and Bruker Avance III (600 MHz)
with TMS as an internal standard; chemical shifts d in ppm with
respect to TMS; coupling constants J in Hz. 13C NMR spectra were
recorded for CDCl3,CD3OD or DMSO-d6 solutions on a Varian Mer-
cury-300 and Bruker Avance III (600 MHz) spectrometer at 75.5
and 150.5 MHz, respectively. 31P NMR spectra were taken in CDCl3
or CD3OD on Varian Mercury-300 and Bruker Avance III at 121.5
and 242 MHz.
IR spectral data were measured on an Infinity MI-60 FT-IR spec-
trometer. Melting points were determined on a Boetius apparatus
and are uncorrected. Elemental analyses were performed by the
Microanalytical Laboratory of this Faculty on a Perkin Elmer PE
2400 CHNS analyzer. Polarimetric measurements were conducted
on an Optical Activity PolAAr 3001 apparatus.
The following adsorbents were used: column chromatography,
Merck silica gel 60 (70–230 mesh); analytical TLC, Merck TLC plas-
tic sheets silica gel 60 F254. TLC plates were developed in chloro-
formmethanol solvent systems. Visualization of the spots was
effected with iodine vapours. All solvents were purified by meth-
ods described in the literature.
All microwave irradiation experiments were carried out in a
microwave reactor Plazmartonika RM 800. The reaction carried
out in 50 mL-glass vials.
Yield: 76%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
11.8 (c 0.77 in CHCl3); mp: 145–147 °C; IR (KBr):
2827, 1682, 1604, 1220, 1023, 754, 698 cmꢀ1 1H NMR (300 MHz,
a]
D
m
= 3290, 3031,
;
CDCl3): d = 8.77 (br s, 1H, NH), 7.70 (s, 1H, HC50), 7.33–7.27 (m,
11H, 10Haromat, 1H, CH3C@CH), 7.23–7.18 (m, 3H, Haromat), 7.12–
7.07 (m, 2H, Haromat), 5.09–4.97 (m, 4H, 2ꢁPOCH2Ph), 4.89 (AB,
J = 14.4 Hz, 1H, CHaHb-Thy), 4.83 (AB, J = 14.4 Hz, 1H, CHaHb-Thy),
4.58 (d, J = 10.8 Hz, 1H, OCHaHbPh), 4.57 (dd, J = 13.8 Hz,
J = 5.7 Hz, 1H, H-3a), 4.49 (dd, J = 13.8 Hz, J = 7.5 Hz, 1H, H-3b),
4.32–4.24 (m, 1H, H-2), 4.19 (d, J = 10.8 Hz, 1H, OCHaHbPh), 3.90
(dd, J = 12.0 Hz, J = 2.1 Hz, 1H, H-1), 3.80 (br s, 1H, OH), 1.83 (s,
3H, CH3); 13C NMR (75.5 MHz, CDCl3): d = 164.5, 151.2, 141.9,
140.1, 136.9, 135.9 (d, J = 5.7 Hz, Cipso), 135.8 (d, J = 5.7 Hz, Cipso),
128.7, 128.6, 128.5, 128.3, 128.2, 128.2, 128.1, 127.9, 125.5,
111.3, 75.5, 73.9, 68.8 (d, J = 7.2 Hz, POC), 68.4 (d, J = 7.2 Hz,
POC), 68.3 (d, J = 162.6 Hz, PC), 50.8 (d, J = 10.1 Hz, C-3), 43.0,
12.6; 31P NMR (121.5 MHz, CDCl3): d = 22.85 ppm. Anal. Calcd for
C32H34N5O7P: C, 60.85; H, 5.43; N, 11.09. Found: C, 60.96; H,
5.20; N, 11.30.
4.2.3. (1S,2S)-Dibenzyl 2-benzyloxy-3-{4-[(3,4-dihydro-2,4-
dioxopyrimidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1S,2S)-16c
Yield: 74%; white solid [chromatographed on a silica gel column
with chloroform–methanol (50:1, 20:1, 10:1, v/v) and appropriate
4.1. General procedure for the preparation of 1,2,3-triazoles
To a solution of azidophosphonate (1.00 mmol) in EtOH (1 mL)
and H2O (1 mL) were added CuSO4 ꢁ 5H2O (0.05 mmol), sodium
ascorbate (0.10 mmol) and alkynes (1.00 mmol). The suspension
was microwave irradiated in the microwave reactor (Plazmatroni-
ka RM 800, 800 W) at 40–45 °C for 20 min. After cooling the sol-
vent was removed by vacuum evaporation. The residue was
suspended in chloroform (5 mL) and filtered through a layer of Cel-
ite. The solution was concentrated in vacuo and the crude product
was purified on a silica gel column with chloroform–methanol
mixtures (50:1, 20:1 or 10:1, v/v) to give the desired 1,2,3-
triazoles.
fractions were crystallized from methanol diethyl ether mixture];
20
[a
]
D
34.1 (c 1.50 in DMSO); mp: 178–180 °C; IR (KBr):
m
= 3251,
2931, 2830, 1706, 1242, 1023, 750, 700 cmꢀ1
;
1H NMR (300 MHz,
CDCl3): d = 9.43 (s, 1H, NH), 7.68 (s, 1H, HC50), 7.40 (d, J = 8.1 Hz,
1H, HC@CH), 7.33–7.27 (m, 10H, Haromat), 7.22–7.19 (m, 3H,
Haromat), 7.10–7.07 (m, 2H, Haromat), 5.64 (d, J = 8.1 Hz, 1H, HC=CH),
5.10–5.01 (m, 4H, 2 ꢁ POCH2Ph), 4.94 (AB, J = 14.1 Hz, 1H,
CHaHb-Ura), 4.90 (AB, J = 14.1 Hz, 1H, CHaHb-Ura), 4.59 (d, J = 11.1 Hz,
1H, OCHaHbPh), 4.57 (dd, J = 13.8 Hz, J = 5.1 Hz, 1H, H-3a), 4.48
(dd, J = 13.8 Hz, J = 6.6 Hz, 1H, H-3b), 4.30–4.23 (m, 1H, H-2), 4.19
(d, J = 11.1 Hz, 1H, OCHaHbPh), 3.90 (brd, J = 8.1 Hz, 1H, H-1), 3.40
(br s, 1H, OH); 13C NMR (151 MHz, DMSO-d6): d = 164.1 (s, C@O),
151.2 (s, C@O), 145.8, 142.8, 138.1, 137.2 (d, J = 6.2 Hz, Cipso),
137.1 (d, J = 6.2 Hz, Cipso), 128.9, 128.9, 128.6, 128.5, 128.4, 128.3,
128.2, 128.1, 127.9, 125.1, 101.7, 78.7 (d, J = 2.8 Hz, C-2), 73.0,
67.9 (d, J = 6.7 Hz, POC), 67.8 (d, J = 162.2 Hz, PC), 67.3 (d,
J = 6.7 Hz, POC), 50.8 (d, J = 9.9 Hz, C-3), 42.8; 31P NMR
(121.5 MHz, CDCl3): d = 22.98 ppm. Anal. Calcd for C31H32N5O7P:
C, 60.29; H, 5.22; N, 11.34. Found: C, 60.06; H, 5.03; N, 11.37.
4.2.1. (1S,2S)-Dibenzyl 3-{4-[(6-aminopurin-9-yl)methyl-1H-
1,2,3-triazol-1-yl]}-2-benzyloxy-1-hydroxypropylphosphonate
(1S,2S)-16a
Yield: 86%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
25.6 (c 1.15 in DMSO); mp: <200 °C; IR (KBr):
2872, 1643, 1604, 1245, 1025, 749, 698 cmꢀ1 1H NMR (300 MHz,
CDCl3): d = 8.25 (s, 1H, HC50), 7.86 (s, 1H), 7.64 (s, 1H), 7.30–7.22
a]
D
m
= 3389, 2984,
;
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

6
I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
4.2.4. (1S,2S)-Dibenzyl 3-{4-[(N4-acetylamino-2-oxopyrimidin-
1-yl)methyl]-1H-1,2,3-triazol-1-yl}-2-benzyloxy-1-
hydroxypropylphosphonate (1S,2S)-16d
4.2.7. (1S,2S)-Dibenzyl 2-benzyloxy-3-{4-[(3,7-dimethyl-2,6-
dioxopurin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1S,2S)-16g
Yield: 78%; white solid [crystallized from methanol–diethyl
Yield: 86%; yellow pale oil [chromatographed on a silica gel col-
20
20
ether mixture]; [
(KBr):
700 cmꢀ1
a]
0.8 (c 1.41 in CHCl3); mp: 168–171 °C; IR
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [a]
D
D
m
= 3276, 3033, 2837, 1720, 1660, 1220, 1025, 796,
;
10.8 (c 1.95 in CHCl3); IR (film): = 3267, 3011, 2931, 2893, 1707,
1663, 1253, 1024, 753, 698 cmꢀ1 1H NMR (300 MHz, CDCl3):
1H NMR (300 MHz, CDCl3): d = 10.22 (br s, 1H, NH),
;
8.23 (s, 1H, HC50), 7.82 (d, J = 7.5 Hz, 1H, HC@CH), 7.51 (d,
J = 7.5 Hz, 1H, HC@CH), 7.32–7.22 (m, 10H, Haromat), 7.18–7.07
(m, 5H, Haromat), 5.18–4.97 (m, 6H, 2 ꢁ POCH2Ph, CH2-Cyt), 4.85–
4.75 (m, 2H, H-3a, H-3b), 4.48 (d, J = 11.1 Hz, 1H, OCHaHbPh),
4.35–4.28 (m, 1H, H-2), 4.23 (d, J = 11.1 Hz, 1H, OCHaHbPh), 3.99
(dd, J = 12.0 Hz, J = 2.4 Hz, 1H, H-1), 3.47 (br s, 1H, OH), 2.14 (s,
3H, CH3); 13C NMR (75.5 MHz, CDCl3): d = 171.4, 162.7, 155.6,
148.5, 141.4, 137.3, 136.1 (d, J = 5.4 Hz, Cipso), 135.9 (d, J = 5.7 Hz,
d = 7.60 (s, 1H, HC50), 7.42 (s, 1H), 7.34–7.12 (m, 15H, Haromat),
5.28 (s, 2H, CH2), 5.09–4.96 (m, 4H, 2 ꢁ POCH2Ph), 4.56 (dd,
J = 13.8 Hz, J = 5.4 Hz, 1H, H-3a), 4.55 (d, J = 10.2 Hz, 1H,
OCHaHbPh), 4.42 (dd, J = 13.8 Hz, J = 6.3 Hz, 1H, H-3b), 4.24–4.12
(m, 1H, H-2), 4.21 (d, J = 10.2 Hz, 1H, OCHaHbPh), 3.93 (s, 3H,
CH3), 3.87 (dd, J = 11.4 Hz, J = 2.4 Hz, 1H, H-1), 3.52 (s, 3H, CH3),
2.93 (br s, 1H, OH); 13C NMR (75.5 MHz, CDCl3): d = 154.6, 151.1,
148.6, 143.4, 141.8, 137.0, 135.9 (d, J = 6.0 Hz,
Cipso), 135.8
C
ipso), 128.7, 128.6, 128.2, 128.1, 128.0, 127.8, 127.7, 126.9, 97.1,
(d, J = 6.0 Hz, Cipso), 128.6, 128.5, 128.4, 128.3, 128.2, 128.1, 128.0,
127.9, 124.9, 107.8, 77.5, 74.0, 68.5 (d, J = 7.2 Hz, POC), 68.4
(d, J = 162.0 Hz, PC), 68.2 (d, J = 7.2 Hz, POC), 50.5 (d, J = 12.3 Hz,
C-3), 31.6, 33.7, 29.9; 31P NMR (121.5 MHz, CDCl3):
d = 22.96 ppm. Anal. Calcd for C34H36N7O7P: C, 59.56; H, 5.29; N,
14.30. Found: C, 59.28; H, 5.42; N, 14.44.
77.5, 73.6, 68.8 (d, J = 6.9 Hz, POC), 68.7 (d, J = 162.6 Hz, PC), 68.5
(d, J = 6.9 Hz, POC), 50.1 (d, J = 11.1 Hz), 44.9, 24.6; 31P NMR
(121.5 MHz, CDCl3): d = 23.63 ppm. Anal. Calcd for C33H35N6O7P:
C, 60.18; H, 5.36; N, 12.76. Found: C, 60.00; H, 5.13; N, 12.91.
4.2.5. (1S,2S)-Dibenzyl 2-benzyloxy-3-{4-[(3,5-dioxo-1,2,4-
triazin-2-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1S,2S)-16e
4.2.8. (1S,2S)-Dibenzyl 2-benzyloxy-3-{4-[(1,3-dimethyl-2,6-
dioxopurin-7-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1S,2S)-16h
Yield: 93%; white powder [chromatographed on a silica gel
column with chloroform–methanol (50:1, 20:1, 10:1, v/v)];
Yield: 95%; white powder [chromatographed on a silica gel col-
20
[
a
]
20.3 (c 1.15 in CHCl3); mp: 68–70 °C; IR (KBr):
m
= 3262,
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
(c 0.95 in CHCl3); mp: 167–169 °C; IR (KBr): = 3362, 3242, 3140,
2951, 2883, 1705, 1659, 1219, 1018, 745, 697 cmꢀ1 1H NMR
a]
20 2.0
D
D
3033, 2908, 1730, 1673, 1216, 1022, 769, 698 cmꢀ1
;
1H NMR
m
(300 MHz, CDCl3): d = 11.07 (br s, 1H, NH), 7.67 (s, 1H, HC50),
7.35–7.25 (m, 11H, 10Haromat, 1H, HC@N), 7.21–7.14 (m, 3H,
;
(300 MHz, CDCl3): d = 7.78 (s, 1H, HC50), 7.77 (s, 1H), 7.35–7.05
(m, 15H, Haromat), 5.53 (AB, J = 15.0 Hz, 1H, CHaHb), 5.49 (AB,
J = 15.0 Hz, 1H, CHaHb), 5.09–4.97 (m, 4H, 2 ꢁ POCH2Ph), 4.56 (d,
J = 10.8 Hz, 1H, OCHaHbPh), 4.55 (dd, J = 13.8 Hz, J = 5.4 Hz, 1H,
H-3a), 4.46 (dd, J = 13.8 Hz, J = 6.6 Hz, 1H, H-3b), 4.27 (dddd,
J = 8.4 Hz, J = 6.6 Hz, J = 5.4 Hz, J = 2.4 Hz, 1H, H-2), 4.19 (d,
J = 10.8 Hz, 1H, OCHaHbPh), 3.84 (dd, J = 12.0 Hz, J = 2.4 Hz, 1H,
H-1), 3.55 (s, 3H, CH3), 3.35 (s, 3H, CH3), 2.97 (br s, 1H, OH); 13C
NMR (75.5 MHz, CDCl3): d = 155.2, 151.4, 148.7, 141.9, 141.4,
138.8, 135.8 (d, J = 5.7 Hz, Cipso), 135.7 (d, J = 5.7 Hz, Cipso), 128.6,
128.6, 128.5, 128.3, 128.2, 128.1, 128.0, 127.9, 125.1, 106.4, 77.4
(d, J = 2.3 Hz, C-2), 74.0, 68.6 (d, J = 7.0 Hz, POC), 68.5 (d,
J = 7.0 Hz, POC), 68.3 (d, J = 162.2 Hz, PC), 50.9 (d, J = 12.1 Hz, C-3),
41.5, 29.9, 28.1; 31P NMR (121.5 MHz, CDCl3): d = 22.86 ppm. Anal.
Calcd for C34H36N7O7P: C, 59.56; H, 5.29; N, 14.30. Found: C, 59.71;
H, 4.97; N, 14.15.
Haromat), 7.07–7.03 (m, 2H, Haromat), 5.13–5.07 (m, 6H, 2 ꢁ POCH2Ph,
CH2), 4.57 (dd, J = 13.8 Hz, J = 6.0 Hz, 1H, H-3a), 4.52 (d,
J = 10.5 Hz, 1H, OCHaHbPh), 4.50 (dd, J = 13.8 Hz, J = 8.1 Hz, 1H,
H-3b), 4.33–4.26 (m, 1H, H-2), 4.12 (d, J = 10.5 Hz, 1H, OCHaHbPh),
3.92 (dd, J = 11.1 Hz, J = 2.1 Hz, 1H, H-1), 3.07 (br s, 1H, OH); 13C
NMR (75.5 MHz, CDCl3): d = 155.6, 149.5, 141.5, 136.9, 135.8 (d,
J = 5.7 Hz, Cipso), 135.6 (d, J = 5.7 Hz, Cipso), 134.8, 128.6, 128.6,
128.3, 128.2, 128.1, 128.0, 127.9, 125.7, 77.5, 73.9, 68.9 (d,
J = 7.2 Hz, POC), 68.4 (d, J = 7.2 Hz, POC), 68.3 (d, J = 162.6 Hz,
PC), 50.7, 34.6; 31P NMR (121.5 MHz, CDCl3): d = 23.34 ppm. Anal.
Calcd for C30H31N6O7P: C, 58.25; H, 5.05; N, 13.59. Found: C,
58.21; H, 4.82; N, 13.36.
4.2.6. (1S,2S)-Dibenzyl 3-{4-[(3-acetyl-1H-indol-1-yl)methyl]-
1H-1,2,3-triazol-1-yl}-2-benzyloxy-1-
hydroxypropylphosphonate (1S,2S)-16f
Yield: 82%; white powder [chromatographed on a silica gel
4.2.9. (1S,2S)-Dibenzyl 2-benzyloxy-3-{4-[(8-chloro-1,3-
dimethyl-2,6-dioxopurin-7-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1S,2S)-16i
column with chloroform–methanol (50:1, 20:1, 10:1, v/v)];
20
[a
]
3.7 (c 1.08 in CHCl3); mp: 163–165 °C; IR (KBr):
m
= 3148,
D
3063, 3031, 2881, 1645, 1216, 1014, 739, 695 cmꢀ1
;
1H NMR
Yield: 91%; white powder [chromatographed on a silica gel col-
(300 MHz, CDCl3): d = 8.83–8.34 (m, 1H), 7.79 (s, 1H, HC50),
7.35–7.11 (m, 17H, Haromat), 6.98–6.94 (m, 2H, Haromat), 5.36 (s,
2H, CH2), 5.06–4.95 (m, 5H, 2 ꢁ POCH2Ph, OH), 4.53 (dd,
J = 13.8 Hz, J = 4.8 Hz, 1H, H-3a), 4.48 (d, J = 10.8 Hz, 1H,
OCHaHbPh), 3.80 (dd, J = 13.8 Hz, J = 7.5 Hz, 1H, H-3b), 4.93 (dddd,
J = 8.1 Hz, J = 7.5 Hz, J = 4.8 Hz, J = 3.3 Hz, 1H, H-2), 4.06 (d,
J = 10.8 Hz, 1H, OCHaHbPh), 3.87 (dd, J = 11.1 Hz, J = 3.3 Hz, 1H,
H-1), 2.45 (s, 3H, CH3); 13C NMR (75.5 MHz, CDCl3): d = 193.1,
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [a]
20 3.8
D
(c 1.05 in CHCl3); mp: 163–165 °C; IR (KBr):
m
;
= 3302, 3011, 2953,
1H NMR (300 MHz,
2893, 1706, 1668, 1216, 1045, 753, 698 cmꢀ1
CDCl3): d = 7.74 (s, 1H, HC50), 7.34–7.06 (m, 15H, Haromat), 5.58
(AB, J = 15.3 Hz, 1H, CHaHb), 5.57 (AB, J = 15.3 Hz, 1H, CHaHb),
5.09–4.96 (m, 4H, 2ꢁPOCH2Ph), 4.57 (d, J = 10.8 Hz, 1H, OCHaHb
Ph), 4.55 (dd, J = 14.1 Hz, J = 5.7 Hz, 1H, H-3a), 4.45 (dd,
J = 14.1 Hz, J = 7.5 Hz, 1H, H-3b), 4.32–4.24 (m, 1H, H-2), 4.17 (d,
J = 10.8 Hz, 1H, OCHaHbPh), 3.84 (br d, J = 12.0 Hz, 1H, H-1), 3.51
(s, 3H, CH3), 3.39 (s, 3H, CH3), 2.80 (br s, 1H, OH); 13C NMR
(75.5 MHz, CDCl3): d = 154.2, 151.0, 147.0, 141.3, 138.8, 138.7,
135.6 (d, J = 5.7 Hz, Cipso), 135.5 (d, J = 5.7 Hz, Cipso), 128.4, 128.0,
127.9, 127.8, 127.7, 125.1, 107.2, 77.2 (s, C-2), 73.8; 68.6 (d,
J = 7.1 Hz, POC), 68.4 (d, J = 7.1 Hz, POC), 68.0 (d, J = 163.4 Hz, PC),
50.8 (d, J = 10.6 Hz, C-3), 40.8, 29.8, 28.0; 31P NMR (121.5 MHz,
142.8, 136.7, 136.4, 135.8 (d, J = 6.0 Hz,
Cipso), 135.6 (d,
J = 6.0 Hz, Cipso), 134.8, 128.6, 128.4, 128.2, 128.1, 128.0, 126.4,
123.7, 123.6, 122.8, 122.7, 117.5, 109.8, 77.4, 74.0, 68.7 (d,
J = 7.0 Hz, POC), 68.4 (d, J = 7.0 Hz, POC), 68.3 (d, J = 162.0 Hz,
PC), 51.0 (d, J = 11.1 Hz, C-3), 42.4, 27.7; 31P NMR (121.5 MHz,
CDCl3): d = 22.74 ppm. Anal. Calcd for C37H37N4O6P: C, 66.86; H,
5.61; N, 8.43. Found: C, 67.02; H, 5.91; N, 8.27.
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
7
CDCl3): d = 22.73 ppm. Anal. Calcd for C34H35ClN7O7P: C, 56.71; H,
4.90; N, 13.62. Found: C, 56.48; H, 5.12; N, 13.81.
4.53 (dd, J = 14.3 Hz, J = 5.3 Hz, 1H, H-3b), 4.40 (dd, J = 14.3 Hz,
J = 7.4 Hz, 1H, H-3b), 4.14–4.06 (m, 1H, H-2), 4.12 (d, J = 10.9 Hz,
1H, OCHaHbPh), 3.86 (dd, J = 11.2 Hz, J = 2.9 Hz, 1H, H-1), 3.00
(br s, 1H, OH); 13C NMR (151 MHz, CDCl3): d = 168.6 (s, C@O);
161.1 (s, C@O); 149.5 (s, C@O); 142.4 (s, HC@C); 140.3; 136.7;
136.2; 135.9 (d, J = 5.6 Hz, Cipso), 135.8 (d, J = 5.6 Hz, Cipso), 135.1,
131.7, 130,5, 129.2, 128.9, 128.7, 128.7, 128.6, 128.4, 128.2,
128.2, 128.1, 125.1, 123.8, 115.6, 115.2, 77.0 (d, J = 1.3 Hz), 74.1,
68.6 (d, J = 7.2 Hz, POC), 68.4 (d, J = 161.9 Hz, PC), 68.3 (d,
J = 7.2 Hz, POC), 50.9 (d, J = 11.7 Hz, C-3), 38.9; 31P NMR
(121.5 MHz, CDCl3): d = 22.09 ppm. Anal. Calcd for C42H38N5O8P:
C, 65.36; H, 4.96; N, 9.07. Found: C, 65.63; H, 5.18; N, 9.02.
4.2.10. (1S,2S)-Dibenzyl 2-benzyloxy-1-hydroxy-3-{4-[(2-
oxopyridin-1-yl)methyl]-1H-1,2,3-triazol-1-
yl}propylphosphonate (1S,2S)-16j
Yield: 96%; brown oil [chromatographed on a silica gel column
20
with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
0.90 in CHCl3); IR (film):
1025, 754, 695 cmꢀ1 1H NMR (300 MHz, CDCl3): d = 7.72 (s, 1H,
a
]
9.2 (c
D
m
= 3067, 3007, 2913, 2894, 1658, 1217,
;
HC50), 7.55 (dd, J = 6.3 Hz, J = 1.3 Hz, 1H, Haromat), 7.35–7.09 (m,
16H, Haromat), 7.52 (d, J = 9.0 Hz, 1H, Haromat), 6.15 (dt, J = 8.1 Hz,
J = 1.3 Hz, 1H, Haromat), 5.14 (AB, J = 14.4 Hz, 1H, CHaHb), 5.13 (AB,
J = 14.4 Hz, 1H, CHaHb), 5.09–4.98 (m, 4H, 2 ꢁ POCH2Ph), 4.56
(dd, J = 13.8 Hz, J = 5.4 Hz, 1H, H-3a), 4.52 (d, J = 10.8 Hz, 1H, OCHa
HbPh), 4.43 (dd, J = 13.8 Hz, J = 9.0 Hz, 1H, H-3b), 4.27 (ddd,
J = 9.0 Hz, J = 5.4 Hz, J = 2.7 Hz, 1H, H-2), 4.20 (d, J = 10.8 Hz, 1H,
OCHaHbPh), 3.84 (ddd, J = 11.4 Hz, J = 9.0 Hz, J = 2.7 Hz, 1H), 3.40
(dd, J = 9.0 Hz, J = 6.6 Hz, 1H, H-1); 13C NMR (75.5 MHz, CDCl3):
d = 162.2, 142.3, 139.3, 137.7, 136.8, 135.8 (d, J = 5.7 Hz, Cipso),
135.7 (d, J = 5.7 Hz, Cipso), 128.5, 128.5, 128.4, 128.4, 128.2, 128.1,
128.0, 127.9, 125.4, 106.2, 77.3 (d, J = 4.9 Hz, C-2), 73.9, 68.4 (d,
J = 7.2 Hz, POC), 68.1 (d, J = 162.9 Hz, PC), 68.0 (d, J = 7.2 Hz, POC),
50.5 (d, J = 11.4 Hz, C-3), 44.3; 31P NMR (121.5 MHz, CDCl3):
d = 22.96 ppm. Anal. Calcd for C32H33N4O6P: C, 63.99; H, 5.54; N,
9.33. Found: C, 64.26; H, 5.81; N, 9.11.
4.2.13. (1R,2S)-Dibenzyl 3-{4-[(6-aminopurin-9-yl)methyl-1H-
1,2,3-triazol-1-yl]}-2-benzyloxy-1-hydroxypropylphosphonate
(1R,2S)-16a
Yield: 70%; white powder [chromatographed on a silica gel col-
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [a D
(c 0.68 in DMSO); mp: 85–88 °C; IR (KBr): = 3408, 3289, 3115,
2924, 2888, 1668, 1600, 1244, 1020, 754, 697 cmꢀ1 1H NMR
]
20 20.0
m
;
(300 MHz, CDCl3): d = 8.32 (s, 1H), 8.00 (s, 1H), 7.67 (s, 1H), 7.32–
7.22 (m, 10H, Haromat), 7.21–7.13 (m, 3H, Haromat), 7.02–6.98 (m, 2H,
Haromat), 6.16 (br s, 2H, NH2), 5.41 (s, 2H, CH2-Ade), 5.09–4.96 (m,
4H, 2 ꢁ POCH2Ph), 4.70 (dd, J = 14.7 Hz, J = 3.9 Hz, 1H, H-3a), 4.64
(dd, J = 14.7 Hz, J = 5.4 Hz, 1H, H-3b), 4.39 (AB, J = 11.4 Hz, 1H,
OCHaHbPh), 4.27 (AB, J = 11.4 Hz, 1H, OCHaHbPh), 4.11 (dddd, J = 8.4 Hz,
J = 6.0 Hz, J = 5.4 Hz, J = 3.9 Hz, 1H, H-2), 3.99 (dd, J = 8.4 Hz,
J = 6.0 Hz, 1H, H-1), 2.06 (br s, 1H, OH); 13C NMR (151 Hz, DMSO-
d6): d = 156.5, 153.0, 149.8, 142.9; 141.0, 138.6, 137.8 (d, J = 6.4 Hz,
4.2.11. (1S,2S)-Dibenzyl 2-benzyloxy-3-{4-[(3-benzoyl-2,4-
dioxopyrimidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1S,2S)-16k
Cipso), 137.6 (d, J = 6.4 Hz, Cipso), 129.3, 128.8, 128.6, 128.6, 128.5,
Yield: 77%; white powder [chromatographed on a silica gel col-
128.4, 128.2, 128.1, 127.9, 127.5, 125.1, 119.1, 78.7 (d, J = 10.8 Hz,
C-3), 71.7; 68.0 (d, J = 4.7 Hz, POC), 67.3 (d, J = 4.7 Hz, POC), 67.1
(d, J = 161.8 Hz, PC), 40.6, 38.4; 31P NMR (121.5 MHz, CDCl3):
d = 24.32 ppm. Anal. Calcd for C32H33N8O5P ꢁ H2O: C, 58.35; H,
5.36; N, 17.01. Found: C, 58.38; H, 5.14; N, 17.06.
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
16.4 (c 1.10 in CHCl3); mp: 113–114 °C; IR (KBr):
2924, 1748, 1704, 1663, 1235, 1021, 739, 698 cmꢀ1
a]
D
m
= 3418, 3088,
1H NMR
;
(300 MHz, CDCl3): d = 7.89–7.86 (m, 1H, Haromat), 7.87 (d,
J = 8.0 Hz, 1H, HC@CH), 7.63–7.55 (m, 2H, Haromat), 7.58 (s, 1H,
HC50), 7.47–7.40 (m, 2H, Haromat), 7.33–7.26 (m, 11H, Haromat),
7.23–7.20 (m, 3H, Haromat), 7.10–7.07 (m, 2H, Haromat), 5.76 (d,
J = 8.0 Hz, 1H, HC@CH), 5.08–5.00 (m, 4H, 2 ꢁ POCH2Ph), 4.92 (s,
2H, CH2), 4.57 (dd, J = 14.0 Hz, J = 5.2 Hz, 1H, H-3a), 4.58 (d,
J = 10.9 Hz, 1H, OCHaHbPh), 4.45 (dd, J = 14.0 Hz, J = 7.2 Hz, 1H, H-
3b), 4.28–4.20 (m, 1H, H-2), 4.19 (d, J = 10.9 Hz, 1H, OCHaHbPh),
3.88 (dd, J = 11.1 Hz, J = 3.2 Hz, 1H, H-1), 3.10 (br s, 1H, OH); 13C
NMR (75.5 MHz, CDCl3): d = 168.4 (s, C@O), 162.1 (s, C@O), 149.5
4.2.14. (1R,2S)-Dibenzyl 2-benzyloxy-3-{4-[(5-methyl-2,4-
dioxopyrimidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1R,2S)-16b
Yield: 76%; white powder [chromatographed on a silica gel col-
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [a]
20 5.3
D
(c 1.20 in CHCl3); mp: 72–74 °C; IR (KBr):
m = 3277, 3061, 2927,
2855, 1680, 1216, 1012, 739, 696 cmꢀ1; 1H NMR (300 MHz, CDCl3):
d = 9.51 (s, 1H, NH), 7.79 (s, 1H, HC50), 7.39–7.22 (m, 11H,
10 ꢁ Haromat, 1H ꢁ CH3C@CH), 7.22–7.17 (m, 3H, Haromat), 7.09–
(s, C@O), 143.8, 136.5, 135.6 (d, J = 5.7 Hz,
Cipso), 135.5 (d,
J = 5.7 Hz, Cipso), 135.0, 131.2, 130,2, 129.0, 128.6, 128.5, 128.5,
128.3, 128.1, 128.0, 125.1, 102.3, 74.0, 68.6 (d, J = 7.0 Hz, POC),
68.3 (d, J = 7.0 Hz, POC), 68.2 (d, J = 161.9 Hz, PC), 50.7 (d,
7.05 (m, 2H, Haromat), 5.02 (dd, J = 12.3 Hz, J = 8.1 Hz, 4H,
2 ꢁ POCH2Ph), 4.91 (AB, J = 14.7 Hz, 1H, CHaHb-Thy), 4.86 (AB,
J = 14.7 Hz, 1H, CHaHb-Thy), 4.79 (dd, J = 14.4 Hz, J = 3.0 Hz, 1H,
H-3a), 4.58 (dd, J = 14.4 Hz, J = 6.3 Hz, 1H, H-3b), 4.50 (br s, 1H,
OH), 4.38 (AB, J = 10.8 Hz, 1H, OCHaHbPh), 4.33 (AB, J = 10.8 Hz,
1H, OCHaHbPh), 4.15 (dddd, J = 8.1 Hz, J = 6.3 Hz, J = 6.0 Hz,
J = 3.0 Hz, 1H, H-2), 4.20 (dd, J = 8.4 Hz, J = 6.0 Hz, 1H, H-1), 1.87
(s, 3H, CH3); 13C NMR (75.5 MHz, CDCl3): d = 164.7, 151.2, 141.7,
140.3, 136.7, 135.9 (d, J = 7.5 Hz, Cipso), 135.8 (d, J = 7.5 Hz, Cipso),
128.6, 128.6, 128.5, 128.3, 128.2, 128.2, 128.1, 128.1, 128.0,
125.6, 111.2, 77.4, 72.6, 68.5 (d, J = 7.1 Hz, POC), 68.4 (d,
J = 7.1 Hz, POC), 67.6 (d, J = 160.3 Hz, PC), 50.2 (d, J = 7.4 Hz), 43.0,
12.5; 31P NMR (121.5 MHz, CDCl3): d = 22.85 ppm. Anal. Calcd for
J = 10.4 Hz,
C-3),
43.2;31
P
NMR
(121.5 MHz,
CDCl3):
d = 22.20 ppm. Anal. Calcd for C38H36N5O8P: C, 63.24; H, 5.03; N,
9.70. Found: C, 62.97; H, 4.88; N, 10.02.
4.2.12. (1S,2S)-Dibenzyl 2-benzyloxy-3-{4-[(3-benzoyl-2,4-
dioxoquinazolin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1S,2S)-16l
Yield: 82%; white solid [chromatographed on a silica gel column
20
with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
3.85 in CHCl3); mp: 136–138 °C; IR (KBr):
2957, 2894, 1750, 1702, 1664, 1607, 1480, 1390, 1249, 755,
673 cmꢀ1 1H NMR (300 MHz, CDCl3): d = 8.18 (dd, J = 7.9 Hz,
a
]
ꢀ6.4 (c
D
m
= 3430, 3269, 3032,
C32H34N5O7P: C, 60.85; H, 5.43; N, 11.09. Found: C, 61.06; H,
;
5.23; N, 11.22.
J = 1.6 Hz, 1H), 7.95–7.91 (m, 2H, 2 ꢁ o-CH), 7.85 (br d, J = 8.4 Hz,
1H), 7.73 (ddd, J = 7.9 Hz, J = 7.0 Hz, J = 1.6 Hz, 1H), 7.66–7.60 (m,
1H, p-CH), 7.59 (s, 1H, HC50), 7.49–7.43 (m, 2H, 2 ꢁ m-CH), 7.34–
7.25 (m, 11H), 7.20–7.13 (m, 3H), 7.03–7.00 (m, 2H), 5.36 (AB,
JAB = 15.9 Hz, 1H, CHaHb), 5.34 (AB, JAB = 15.9 Hz, 1H, CHaHb),
5.08–4.96 (m, 4H, 2 ꢁ POCH2Ph), 4.54 (d, J = 10.9 Hz, 1H, OCHaHbPh),
4.2.15. (1R,2S)-Dibenzyl 2-benzyloxy-3-{4-[(2,4-
dioxopyrimidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1R,2S)-16c
Yield: 92%; white powder [chromatographed on a silica gel col-
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [a]
20 6.3
D
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

8
I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
(c 1.23 in CHCl3); mp: 73–75 °C; IR (KBr):
m
= 3241, 3033, 2891,
4.2.18. (1R,2S)-Dibenzyl 3-{4-[(3-acetyl-1H-indol-1-yl)methyl]-
2826, 1680, 1214, 1029, 750, 700 cmꢀ1; 1H NMR (300 MHz, CDCl3):
d = 9.48 (s, 1H, NH), 7.76 (s, 1H, HC50), 7.47 (d, J = 7.7 Hz, 1H,
HC=CH), 7.31–7.23 (m, 10H, Haromat), 7.22–7.18 (m, 3H, Haromat),
7.10–7.05 (m, 2H, Haromat), 5.66 (d, J = 7.7 Hz, 1H, HC=CH), 5.04
(dd, J = 11.4 Hz, J = 8.1 Hz, 4H, 2 ꢁ POCH2Ph), 4.98 (AB, J = 14.4 Hz,
1H, CHaHb-Ura), 4.88 (AB, J = 14.4 Hz, 1H, CHaHb-Ura), 4.79 (dd,
J = 14.4 Hz, J = 3.0 Hz, 1H, H-3a), 4.61 (dd, J = 14.4 Hz, J = 6.9 Hz,
1H, H-3b), 4.41 (d, J = 11.1 Hz, 1H, OCHaHbPh), 4.33 (d,
J = 11.1 Hz, 1H, OCHaHbPh), 4.41 (dddd, J = 8.7 Hz, J = 6.9 Hz,
J = 6.0 Hz, J = 3.0 Hz, 1H, H-2), 4.00 (dd, J = 8.7 Hz, J = 6.0 Hz, 1H,
H-1), 1.88 (br s, 1H, OH); 13C NMR (75.5 MHz, CDCl3): d = 164.2
(s, C@O), 151.1 (s, C@O), 144.5, 141.5, 136.7, 135.9 (d, J = 6.6 Hz,
1H-1,2,3-triazol-1-yl}-2-benzyloxy-1-
hydroxypropylphosphonate (1R,2S)-16f
Yield: 91%; white powder [chromatographed on a silica gel col-
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [a]
20
D
+7.7 (c 1.09 in CHCl3); mp: 133–135 °C; IR (KBr):
m = 3224, 3033,
2891, 1643, 1231, 1012, 749, 695 cmꢀ1; 1H NMR (300 MHz, CDCl3):
d = 8.40–8.36 (m, 1H), 7.81 (s, 1H, HC50), 7.37–7.11 (m, 17H,
Haromat), 6.96–6.93 (m, 2H, Haromat), 5.39 (s, 2H, CH2), 5.30–4.96
(m, 4H, 2 ꢁ POCH2Ph), 4.66 (dd, J = 14.5 Hz, J = 3.4 Hz, 1H, H-3a),
4.53 (dd, J = 14.5 Hz, J = 6.7 Hz, 1H, H-3b), 4.35 (d, J = 11.1 Hz,
1H, OCHaHbPh), 4.14 (d, J = 11.1 Hz, 1H, OCHaHbPh), 4.12–4.06 (m,
2H, H-2, OH), 3.93 (dd, J = 8.9 Hz, J = 5.4 Hz, 1H, H-1), 2.47 (s, 3H,
CH3); 13C NMR (75.5 MHz, CDCl3): d = 193.2, 142.4, 136.6, 136.4,
135.7 (d, J = 5.7 Hz, Cipso), 135.6 (d, J = 5.7 Hz, Cipso), 135.0, 128.5,
128.3, 128.0, 127.9, 127.8, 126.4, 123.9, 123.5, 122.7, 122.6, 117.3,
109.8, 77.8, 72.0, 68.5 (d, J = 6.8 Hz, POC), 68.4 (d, J = 6.8 Hz,
POC), 67.6 (d, J = 161.8 Hz, PC), 50.5, 42.3, 27.6; 31P NMR
(121.5 MHz, CDCl3): d = 23.68 ppm. Anal. Calcd for C37H37N4O6P:
C, 66.86; H, 5.61; N, 8.43. Found: C, 66.73; H, 5.49; N, 8.53.
Cipso), 135.8 (d, J = 6.6 Hz, Cipso), 128.8, 128.7, 128.6, 128.4, 128.3,
128.2, 128.2, 128.1, 125.7, 102.7, 77.4, 72.7, 68.7 (d, J = 7.0 Hz,
POC), 68.7 (d, J = 7.0 Hz, POC), 67.5 (d, J = 147.4 Hz, PC), 50.3 (d,
J = 7.4 Hz, C-3), 43.2; 31P NMR (121.5 MHz, CDCl3): d = 23.40 ppm.
Anal. Calcd for C31H32N5O7P: C, 60.29; H, 5.22; N, 11.34. Found:
C, 60.56; H, 5.14; N, 11.58.
4.2.16. (1R,2S)-Dibenzyl 3-{4-[(N4-acetylamino-2-oxopyrimidin-
1-yl)methyl]-1H-1,2,3-triazol-1-yl}-2-benzyloxy-1-
hydroxypropylphosphonate (1R,2S)-16d
4.2.19. (1R,2S)-Dibenzyl 2-benzyloxy-3-{4-[(3,7-dimethyl-2,6-
dioxopurin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1R,2S)-16g
Yield: 80%; white powder [chromatographed on a silica gel col-
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [a]
Yield: 75%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+20.1 (c 0.96 in CHCl3); mp: 82–84 °C; IR (KBr):
2937, 2854, 1720, 1660, 1222, 1025, 744, 697 cmꢀ1
a]
D
20
m
= 3256, 3033,
D
;
1H NMR
+9.9 (c 0.91 in CHCl3); mp: 72–74 °C; IR (KBr): = 3260, 3011,
(300 MHz, CDCl3): d = 10.96 (br s, 1H, NH), 8.88 (s, 1H, HC50),
8.05 (d, J = 6.9 Hz, 1H, HC@CH), 7.44 (d, J = 6.9 Hz, 1H, HC@CH),
7.33–7.08 (m, 15H, Haromat), 5.41 (d, J = 14.4 Hz, 1H, CHaHb-Cyt),
5.08–4.80 (m, 5H, 2 ꢁ POCH2Ph, H-3a), 4.89 (d, J = 14.4 Hz, 1H,
CHaHb-Cyt), 4.76 (dd, J = 14.4 Hz, J = 8.7 Hz, 1H, H-3b), 4.73 (AB,
J = 10.8 Hz, 1H, OCHaHbPh), 4.39 (AB, J = 10.8 Hz, 1H, OCHaHbPh),
4.10 (dddd, J = 9.3 Hz, J = 8.7 Hz, J = 3.3 Hz, J = 2.7 Hz, 1H, H-2),
3.93 (br d, J = 9.3 Hz, 1H, H-1), 3.07 (br s, 1H, OH), 2.18 (s, 3H,
CH3); 13C NMR (75.5 MHz, CDCl3): d = 171.4, 162.9, 155.6, 149.1,
141.3, 137.0, 136.0 (d, J = 5.4 Hz, Cipso), 128.6, 128.5, 128.4, 128.3,
128.2, 128.0, 127.9, 127.0, 97.0, 77.4, 72.3, 68.5 (d, J = 4.3 Hz,
POC), 68.4 (d, J = 4.3 Hz, POC), 66.9 (d, J = 161.2 Hz, PC), 48.9,
44.6, 24.9; 31P NMR (121.5 MHz, CDCl3): d = 27.48 ppm. Anal. Calcd
for C33H35N6O7P: C, 60.18; H, 5.36; N, 12.76. Found: C, 59.87; H,
5.44; N, 12.82.
2951, 2894, 1707, 1663, 1223, 1022, 753, 699 cmꢀ1 1H NMR
;
(300 MHz, CDCl3): d = 7.61 (s, 1H, HC50), 7.48 (s, 1H), 7.32–7.24
(m, 10H, Haromat), 7.22–7.19 (m, 3H, Haromat), 7.14–7.09 (m, 2H,
Haromat), 5.29 (s, 2H, CH2), 5.02 (dd, J = 13.2 Hz, J = 8.4 Hz, 4H,
2 ꢁ POCH2Ph), 4.67 (dd, J = 14.7 Hz, J = 3.6 Hz, 1H, H-3a), 4.58
(dd, J = 14.7 Hz, J = 6.3 Hz, 1H, H-3b), 4.40 (d, J = 11.1 Hz, 1H, OCHa
HbPh), 4.29 (d, J = 11.1 Hz, 1H, OCHaHbPh), 4.16 (dddd, J = 9.6 Hz,
J = 6.6 Hz, J = 6.3 Hz, J = 3.6 Hz, 1H, H-2), 3.95 (dd, J = 9.6 Hz,
J = 6.0 Hz, 1H, H-1), 3.94 (s, 3H, CH3), 3.52 (s, 3H, CH3), 1.93 (br s,
1H, OH); 13C NMR (75.5 MHz, CDCl3): d = 154.6, 151.1, 148.8,
143.2, 141.6, 137.0, 136.0 (d, J = 6.0 Hz, Cipso), 135.8 (d, J = 6.0 Hz,
Cipso), 128.6, 128.5, 128.3, 128.2, 128.1, 128.0, 127.8, 125.0, 107.5,
78.1 (d, J = 5.2 Hz, C-2), 72.8, 68.5 (d, J = 6.9 Hz, POC), 68.4 (d,
J = 6.9 Hz, POC), 67.9 (d, J = 161.8 Hz, PC), 50.4 (d, J = 4.7 Hz, C-3),
36.1, 33.7, 29.8; 31P NMR (121.5 MHz, CDCl3): d = 24.09 ppm. Anal.
Calcd for C34H36N7O7P ꢁ H2O: C, 58.03; H, 5.44; N, 13.93. Found: C,
58.35; H, 5.26; N, 13.87.
4.2.17. (1R,2S)-Dibenzyl 2-benzyloxy-3-{4-[(3,5-dioxo-1,2,4-
triazin-2-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1R,2S)-16e
4.2.20. (1R,2S)-Dibenzyl 2-benzyloxy-3-{4-[(1,3-dimethyl-2,6-
dioxopurin-7-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1R,2S)-16h
Yield: 91%; colorless oil [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
2.3 (c 1.42 in CHCl3); IR (film):
1241, 998, 740, 696 cmꢀ1 1H NMR (300 MHz, CDCl3): d = 11.41
a]
D
m
= 3242, 3033, 2907, 1730, 1673,
Yield: 91%; colorless oil [chromatographed on a silica gel col-
20
;
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+2.8 (c 1.05 in CHCl3); IR (film):
1660, 1212, 998, 746, 697 cmꢀ1
a]
D
(br s, 1H, NH), 7.68 (s, 1H, HC5’), 7.31 (s, 1H, HC@N), 7.29–7.21
(m, 10H, Haromat), 7.20–7.16 (m, 3H, Haromat), 7.09–7.03 (m, 2H,
m
= 3243, 2953, 2893, 1703,
;
1H NMR (300 MHz, CDCl3):
H
aromat), 5.13 (AB, J = 14.7 Hz, 1H, CHaHb), 5.10 (AB, J = 14.7 Hz,
d = 7.80 (s, 1H, HC50), 7.47 (s, 1H), 7.35–7.25 (m, 10H, Haromat),
7.23–7.15 (m, 3H, Haromat), 7.06–7.02 (m, 2H, Haromat), 5.52 (s, 2H,
CH2), 5.09–4.97 (m, 4H, 2 ꢁ POCH2Ph), 4.70 (dd, J = 14.1 Hz,
J = 3.3 Hz, 1H, H-3a), 4.61 (dd, J = 14.1 Hz, J = 6.6 Hz, 1H, H-3b),
4.44 (d, J = 11.4 Hz, 1H, OCHaHbPh), 4.25 (d, J = 11.4 Hz, 1H, OCHa-
HbPh), 4.14 (dddd, J = 9.3 Hz, J = 6.6 Hz, J = 5.7 Hz, J = 3.3 Hz, 1H,
H-2), 3.97 (dd, J = 8.4 Hz, J = 5.7 Hz, 1H, H-1); 3.60 (br s, 1H, OH),
3.54 (s, 3H, CH3), 3.33 (s, 3H, CH3), 13C NMR (75.5 MHz, CDCl3):
d = 155.2; 151.4; 148.7; 141.9; 141.4, 136.8, 135.8 (d, J = 5.4 Hz,
1H, CHaHb), 5.06–4.98 (m, 4H, 2 ꢁ POCH2Ph), 4.71 (dd,
J = 14.4 Hz, J = 3.3 Hz, 1H, H-3a), 4.60 (dd, J = 14.4 Hz, J = 6.3 Hz,
1H, H-3b), 4.39 (d, J = 11.1 Hz, 1H, OCHaHbPh), 4.27 (d,
J = 11.1 Hz, 1H, OCHaHbPh), 4.14 (dddd, J = 9.3 Hz, J = 6.3 Hz,
J = 6.3 Hz, J = 3.3 Hz, 1H, H-2), 4.01 (dd, J = 8.4 Hz, J = 6.3 Hz, 1H,
H-1), 3.00 (br s, 1H, OH); 13C NMR (75.5 MHz, CDCl3): d = 155.7,
149.3, 141.3, 136.8, 135.9 (d, J = 5.7 Hz, Cipso), 135.8 (d, J = 5.7 Hz,
Cipso), 128.5, 128.4, 128.3, 128.1, 128.0, 127.9, 127.8, 125.7, 77.4,
72.7, 68.7 (d, J = 6.9 Hz, POC), 68.5 (d, J = 6.9 Hz, POC), 67.7 (d,
J = 162.9 Hz, PC), 50.4, 34.7; 31P NMR (121.5 MHz, CDCl3):
d = 24.40 ppm. Anal. Calcd for C30H31N6O7P: C, 58.25; H, 5.05; N,
13.59. Found: C, 58.52; H, 5.08; N, 13.67.
Cipso), 135.6 (d, J = 5.4 Hz, Cipso), 128.6, 128.5, 128.4, 128.2, 128.0,
127.9, 127.8, 125.1, 106.4, 77.4 (s, C-2), 72.6, 68.6 (d, J = 7.0 Hz,
POC), 68.4 (d, J = 7.0 Hz, POC), 67.4 (d, J = 147.2 Hz, PC), 50.4 (d,
J = 6.0 Hz, C-3), 41.5, 29.9, 28.1; 31P NMR (121.5 MHz, CDCl3):
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
9
d = 23.91 ppm. Anal. Calcd for C34H36N7O7P: C, 59.56; H, 5.29; N,
14.30. Found: C, 59.82; H, 5.13; N, 14.22.
C@O), 144.2, 136.7, 135.9 (d, J = 5.4 Hz, Cipso), 135.8 (d, J = 5.4 Hz,
Cipso), 135.1, 131.5, 130,5, 129.2, 128.7, 128.7, 128.6, 128.5, 128.2,
128.2, 102.7, 75.5 (d, J = 4.4 Hz, C-2), 68.6 (d, J = 6.7 Hz, POC),
68.5 (d, J = 6.7 Hz, POC), 67.7 (d, J = 161.8 Hz, PC), 50.5 (d,
J = 3.9 Hz, C-3), 43.1; 31P NMR (121.5 MHz, CDCl3): d = 23.31 ppm.
Anal. Calcd for C38H36N5O8P: C, 63.24; H, 5.03; N, 9.70. Found: C,
63.17; H, 5.33; N, 9.57.
4.2.21. (1R,2S)-Dibenzyl 2-benzyloxy-3-{4-[(8-chloro-1,3-
dimethyl-2,6-dioxopurin-7-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1R,2S)-16i
Yield: 85%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+3.3 (c 1.35 in CHCl3); mp: 69–71 °C; IR (KBr):
2952, 2863, 1706, 1663, 1214, 994, 744, 698 cmꢀ1
(300 MHz, CDCl3): d = 7.77 (s, 1H, HC50), 7.34–7.25 (m, 10H,
aromat), 7.24–7.14 (m, 3H, Haromat), 7.07–7.01 (m, 2H, Haromat),
a]
D
m
= 32662, 3010,
1H NMR
4.2.24. (1R,2S)-Dibenzyl 2-benzyloxy-3-{4-[(3-benzoyl-2,4-
dioxoquinazolin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1R,2S)-16l
;
H
Yield: 88%; white solid [chromatographed on a silica gel column
20
5.58 (s, 2H, CH2), 5.09–4.96 (m, 4H, 2 ꢁ POCH2Ph), 4.70 (dd,
J = 14.4 Hz, J = 3.3 Hz, 1H, H-3a), 4.59 (dd, J = 14.4 Hz, J = 6.6 Hz,
1H, H-3b), 4.40 (d, J = 11.1 Hz, 1H, OCHaHbPh), 4.24 (d,
J = 11.1 Hz, 1H, OCHaHbPh), 4.19–4.09 (m, 1H, H-2), 3.97 (dd,
J = 9.0 Hz, J = 6.0 Hz, 1H, H-1), 3.67 (br s, 1H, OH), 3.51 (s, 3H,
CH3), 3.32 (s, 3H, CH3); 13C NMR (75.5 MHz, CDCl3): d = 154.2,
151.0, 147.0, 141.3, 138.8, 136.7, 135.6 (d, J = 6.0 Hz, Cipso), 135.6
(d, J = 6.0 Hz, Cipso), 128.6, 128.5, 128.2, 128.0, 127.9, 127.8, 127.7,
125.1, 107.2, 77.4 (s, C-2), 72.8, 68.5 (d, J = 6.0 Hz, POC), 68.4 (d,
J = 6.0 Hz, POC), 67.8 (d, J = 161.4 Hz, PC), 50.8 (d, J = 5.9 Hz, C-3),
41.0, 29.8, 28.0; 31P NMR (121.5 MHz, CDCl3): d = 23.85 ppm. Anal.
Calcd for C34H35ClN7O7P: C, 56.71; H, 4.90; N, 13.62. Found: C,
56.72; H, 4.72; N, 13.53.
with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
2.34 in CHCl3); mp: 145–147 °C; IR (KBr):
2855, 1749, 1702, 1665, 1608, 1480, 1391, 1249, 754, 691 cmꢀ1
a
]
+2.9 (c
D
m
= 3418, 3277, 2925,
;
1H NMR (300 MHz, CDCl3): d = 8.17 (dd, J = 8.0 Hz, J = 1.6 Hz, 1H),
7.95–7.91 (m, 2H, 2 ꢁ o-CH), 7.86 (br d, J = 8.5 Hz, 1H), 7.71 (ddd,
J = 8.8 Hz, J = 7.3 Hz, J = 1.6 Hz, 1H), 7.61 (s, 1H, HC50), 7.64–7.38
(m, 1H, p-CH), 7.47–7.41 (m, 2H, 2 ꢁ m-CH), 7.30–7.23 (m, 11H),
7.16–7.08 (m, 3H), 7.00–6.96 (m, 2H), 5.34 (s, 2H, CH2), 5.00 (t,
4H, J = 8.3 Hz, 2 ꢁ POCH2Ph), 4.67 (dd, J = 14.5 Hz, J = 3.1 Hz, 1H,
H-3b), 4.54 (dd, J = 14.5 Hz, J = 6.9 Hz, 1H, H-3b), 4.37 (AB,
JAB = 11.2 Hz, 1H, OCHaHbPh), 4.17 (AB, JAB = 11.2 Hz, 1H, OCHaHb
Ph), 4.14–4.06 (m, 1H, H-2), 3.98 (dd, J = 8.9 Hz, J = 5.7 Hz, 1H, H-
1), 1.85 (br s, 1H, OH); 13C NMR (151 MHz, CDCl3): d = 168.6 (s,
C@O); 161.1 (s, C@O); 149.5 (s, C@O); 142.4 (s, HC@C); 140.3;
136.7; 136.2; 135.9 (d, J = 5.4 Hz, Cipso), 135.8 (d, J = 5.4 Hz, Cipso),
135.0, 131.7, 130.5, 129.2, 128.9, 128.7, 128.6, 128.4, 128.2,
128.1, 128.1, 125.3, 123.8, 115.6, 115.3, 77.6 (d, J = 4.8 Hz), 72.9,
68.5 (d, J = 6.8 Hz, POC), 68.4 (d, J = 6.8 Hz, POC), 68.0 (d,
J = 161.4 Hz, PC), 50.4 (d, J = 6.0 Hz, C-3), 38.9; 31P NMR
(121.5 MHz, CDCl3): d = 23.37 ppm. Anal. Calcd for C42H38N5O8P:
C, 65.36; H, 4.96; N, 9.07. Found: C, 65.17; H, 5.18; N, 8.87.
4.2.22. (1R,2S)-Dibenzyl 2-benzyloxy-1-hydroxy-3-{4-[(2-
oxopyridin-1-yl)methyl]-1H-1,2,3-triazol-1-
yl}propylphosphonate (1R,2S)-16j
Yield: 81%; brown oil [chromatographed on a silica gel column
20
with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
0.78 in CHCl3); IR (film):
1024, 751, 695 cmꢀ1 1H NMR (300 MHz, CDCl3): d = 7.77 (s, 1H,
a
]
+4.5 (c
D
m
= 3267, 3067, 2953, 2890, 1657, 1216,
;
HC50), 7.60–7.54 (m, 1H, Haromat), 7.31–7.23 (m, 11H, Haromat),
7.22–7.13 (m, 3H, Haromat), 7.07–7.02 (m, 2H, Haromat), 6.53–5.58
(m, 1H, Haromat), 6.14 (dt, J = 6.9 Hz, J = 1.2 Hz, 1H, Haromat), 5.17
(br s, 1H, OH), 5.12 (s, 2H, CH2), 5.06–4.98 (m, 4H, 2ꢁPOCH2Ph),
4.72 (dd, J = 14.4 Hz, J = 3.3 Hz, 1H, H-3a), 4.59 (dd, J = 14.4 Hz,
J = 6.6 Hz, 1H, H-3b), 4.42 (d, J = 11.1 Hz, 1H, OCHaHbPh), 4.26 (d,
J = 11.1 Hz, 1H, OCHaHbPh), 4.14 (dddd, J = 9.3 Hz, J = 6.6 Hz,
J = 5.4 Hz, J = 3.3 Hz, 1H, H-2), 4.06–4.01 (m, 1H, H-1); 13C NMR
(75.5 MHz, CDCl3): d = 162.2, 142.3, 139.9, 137.8, 136.0, 135.9 (d,
J = 6.0 Hz, Cipso), 135.8 (d, J = 6.0 Hz, Cipso), 128.5, 128.4, 128.3,
128.2, 128.1, 128.0, 125.4, 106.2, 77.6 (s, C-2), 72.9, 68.5 (d,
J = 6.9 Hz, POC), 68.4 (d, J = 6.9 Hz, POC), 67.7 (d, J = 162.3 Hz, PC),
50.4 (d, J = 6.9 Hz, C-3), 44.3; 31P NMR (121.5 MHz, CDCl3):
d = 24.51 ppm. Anal. Calcd for C32H33N4O6P: C, 63.99; H, 5.54; N,
9.33. Found: C, 63.75; H, 5.33; N, 9.46.
4.2.25. (1S,2R,3S)-Dibenzyl 4-{[4-(6-amino-purin-9-yl)methyl]-
1H-1,2,3-triazol-1-yl}-1,2,3-trihydroxy-2,3-O-
isopropylidenebutylphosphonate (1S,2R,3S)-17a
Yield: 83%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [a]
D
21.7 (c 1.12 in DMSO); mp: 193–195 °C; IR (KBr):
m
;
= 3233, 3187,
1H NMR (CD3
2957, 2925, 1646, 1216, 1047, 996, 777, 698 cmꢀ1
OD, 600 MHz): d = 8.25 (s, 1H, N@CH), 8.21 (s, 1H, HCN), 8.00 (s
1H, HC50), 7.407.32 (m, 10H, 2xC6H5), 5.55 (s, 2H, HC@CCH2),
5.185.08 (m, 4H, 2 ꢁ POCH2Ph), 4.74 (dd, J = 14.5 Hz, J = 2.9 Hz,
1H, H-4b), 4.64 (dd, J = 14.5 Hz, J = 6.8 Hz, 1H, H-4b), 4.50 (dt,
J = 6.8 Hz, J = 2.9 Hz, 1H, H-3), 4.17 (dd, J = 8.9 Hz, J = 5.7 Hz, 1H,
H-1), 4.06 (dt, J = 6.8 Hz, J = 5.7 Hz, 1H, H-2), 1.32 (s, 3H, CH3),
1.14 (s, 3H, CH3); 13C NMR (151 MHz, CD3OD): d = 156.4, 153.0,
149.8, 142.9, 141.1, 137.1 (d, J = 5.7 Hz, Cipso), 137.0 (d, J = 5.5 Hz,
Cipso), 128.8, 128.6, 128.6, 128.2, 128.1, 125.1, 119.1, 110.1 (s,
C(CH3)2), 77.5 (d, J = 8.5 Hz, C-3), 76.8 (d, J = 8.2 Hz, C-2), 67.9 (d,
J = 162.7 Hz, C-1), 67.9 (d, J = 6.6 Hz, COP), 67.4 (d, J = 6.6 Hz,
COP), 52.3 (s, C-4), 38.4 (s, HC@CACH2AN), 27.2 (s, CH3), 27.2 (s,
CH3); 31P NMR (CD3OD, 242 MHz): d = 22.57 ppm. Anal. Calcd for
4.2.23. (1R,2S)-Dibenzyl 2-benzyloxy-3-{4-[(3-benzoyl-2,4-
dioxopyrimidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1-
hydroxypropylphosphonate (1R,2S)-16k
Yield: 81%; colorless oil [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [a]
D
+3.4 (c 3.77 in CHCl3); IR (film):
m
= 3410, 3260, 2924, 2853,
C29H33N8O6P: C, 56.13; H, 5.36; N, 18.06. Found: C, 55.87; H,
5.24; N, 17.85.
1748, 1705, 1664, 1237, 740, 697 cmꢀ1; 1H NMR (300 MHz, CDCl3):
d = 7.90–7.86 (m, 2H), 7.68–7.56 (m, 3H), 7.47–7.42 (m, 2H,
H
aromat), 7.33–7.26 (m, 11H, Haromat), 7.24–7.18 (m, 2H, Haromat),
4.2.26. (1S,2R,3S)-Dibenzyl 4-{[4-(5-methyl-2,4-dioxopyrimidin-
1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-trihydroxy-2,3-O-
isopropylidenebutylphosphonate (1S,2R,3S)-17b
7.08–7.05 (m, 2H, Haromat), 5.78 (d, J = 7.7 Hz, 1H, HC@CH), 5.08–
5.00 (m, 4H, 2 ꢁ POCH2Ph), 4.96 (s, 2H, CH2), 4.67–4.62 (m, 2H,
H-3b, H-3a), 4.42 (AB, JAB = 11.3 Hz, 1H, OCHaHbPh), 4.28 (AB,
JAB = 11.3 Hz, 1H, OCHaHbPh), 4.17–4.07 (m, 1H, H-2), 3.91 (dd,
J = 8.7 Hz, J = 5.8 Hz, 1H, H-1), 1.80 (br s, 1H, OH); 13C NMR
(151 MHz, CDCl3): d = 168.7 (s, C@O), 162.3 (s, C@O), 149.8 (s,
Yield: 83%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
11.5 (c 1.12 in DMSO); mp: 194–195 °C; IR (KBr):
2957, 2823, 1682, 1214, 1057, 745, 695 cmꢀ1 1H NMR (CDCl3,
a]
D
m
= 3238, 3034,
;
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

10
I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
600 MHz): d = 8.58 (br s, 1H, NH), 7.80 (s 1H, HC50), 7.427.38 (m,
11H, 2 ꢁ C6H5, HC@C), 5.155.08 (m, 4H, 2 ꢁ POCH2Ph), 4.96 (AB,
JAB = 15.0 Hz, 1H, CHaHb), 4.94 (AB, JAB = 15.0 Hz, 1H, CHaHb), 4.75
(dd, J = 14.4 Hz, J = 2.6 Hz, 1H, H-4b), 4.58 (dd, J = 14.4 Hz,
J = 6.4 Hz, 1H, H-4a), 4.50 (dt, J = 2.6 Hz, J = 6.4 Hz, 1H, H-3), 4.15
(dt, J = 7.6 Hz, J = 6.4 Hz, 1H, H-2), 4.05 (dt, J = 7.6 Hz, J = 5.3 Hz,
1H, H-1), 3.40 (dd, J = 12.6 Hz, J = 5.3 Hz, 1H), 1.95 (s, 3H, CH3),
1.38 (s, 3H, CH3), 1.22 (s, 3H, CH3); 13C NMR (151 MHz, DMSO-
d6): d = 164.7 (s, C@O), 151.2 (s, C@O), 142.8 (s, HC@CACH3),
141.6, 137.1 (d, J = 5.6 Hz, Cipso), 137.0 (d, J = 5.6 Hz, Cipso), 128.9,
128.6, 128.6, 128.2, 128.1 (Caromat), 125.1, 110.1 (s, C(CH3)2),
109.4 (s, HC@CCH3), 77.4 (d, J = 8.0 Hz), 76.8 (d, J = 8.0 Hz), 68.0
(d, J = 6.7 Hz, POC), 67.9 (d, J = 162.7 Hz, PC), 67.5 (d, J = 6.7 Hz,
POC), 52.3 (s, C-4), 42.6, 27.2, 12.4; 31P NMR (CDCl3, 242 MHz):
d = 21.48 ppm. Anal. Calcd for C29H34N5O8P: C, 56.95; H, 5.60; N,
11.45. Found: C, 56.92; H, 5.53; N, 11.28.
4.2.29. (1S,2R,3S)-Dibenzyl 4-{[4-(3,7-dimethyl-2,6-dioxopurin-
1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-trihydroxy-2,3-O-
isopropylidenebutylphosphonate (1S,2R,3S)-17g
Yield: 88%; white powder [chromatographed on a silica gel col-
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
(c 1.96 in CHCl3); mp: 187–188 °C; IR (KBr): = 3275, 3012, 2998,
2965, 1708, 1663, 1218, 1023, 757, 693 cmꢀ1 1H NMR (CDCl3,
a]
20 9.3
D
m
;
600 MHz): d = 7.70 (s 1H, HC50), 7.48 (s, 1H, NCH@N), 7.407.25
(m, 10H, 2 ꢁ C6H5), 5.35 (AB, JAB = 14.5 Hz, 1H, CHaHb), 5.33 (AB,
JAB = 14.5 Hz, 1H, CHaHb), 5.185.05 (m, 4H, 2 ꢁ POCH2Ph), 4.69
(dd, J = 14.5 Hz, J = 2.9 Hz, 1H, H-4a), 4.60 (dd, J = 14.5 Hz,
J = 5.8 Hz, 1H, H-4b), 4.50 (ddd, J = 7.6 Hz, J = 5.8 Hz, J = 2.9 Hz,
1H, H-3), 4.13 (dt, J = 10.6 Hz, J = 5.5 Hz, 1H, H-1), 4.05 (dt,
J = 7.6 Hz, J = 5.5 Hz, 1H, H-2), 4.00 (s, 3H, NCH3), 3.58 (s, 3H,
NCH3), 3.29 (dd, J = 12.9 Hz, J = 5.5 Hz, 1H), 1.36 (s, 3H, CH3), 1.24
(s, 3H, CH3), 13C NMR (151 MHz, CDCl3): d = 154.8 (s, C@O), 151.3
(s, C@O), 148.9, 143.3, 141.6, 136.0 (d, J = 5.3 Hz, Cipso), 135.9 (d,
J = 6.0 Hz, Cipso), 128.6, 128.6, 128.5, 128.5, 128.2, 128.0 (Caromat),
124.9, 110.3 (s, C(CH3)2), 107.7, 76.7 (d, J = 7.8 Hz), 76.6 (d,
J = 3.9 Hz), 68.6 (d, J = 7.1 Hz, COP), 68.6 (d, J = 162.3 Hz, C-1),
68.5 (d, J = 7.1 Hz, COP), 51.9 (s, C-4), 35.9 (s, HC@CACH2), 35.9
(s, CH3), 33.6 (s, CH3), 29.7 (s, CH3), 26.9 (s, CH3), 26.8(s, CH3);
31P NMR (CDCl3, 242 MHz): d = 21.64 ppm. Anal. Calcd for C31H36
N7O8P: C, 55.94; H, 5.45; N, 14.73. Found: C, 55.73; H, 5.43; N,
14.69.
4.2.27. (1S,2R,3S)-Dibenzyl 4-{[4-(2,4-dioxopyrimidin-1-
yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-trihydroxy-2,3-O-
isopropylidenebutylphosphonate (1S,2R,3S)-17c
Yield: 85%; yellow pale powder [chromatographed on a silica
gel column with chloroform–methanol (50:1, 20:1, 10:1, v/v)];
20
[a
]
D
28.3 (c 1.07 in CH3OH); mp: 157–159 °C; IR (KBr):
m
= 3231, 3061, 2891, 2826, 1675, 1226, 1052, 996, 737,
696 cmꢀ1 1H NMR (CD3OD, 600 MHz): d = 7.95 (s 1H, HC50), 7.70
;
(d, J = 7.9 Hz, 1H, HC@CH), 7.427.32 (m, 10H, 2 ꢁ C6H5), 5.68 (d,
J = 7.6 Hz, 1H, HC@CH), 5.175.09 (m, 4H, 2 ꢁ POCH2Ph), 5.06 (AB,
JAB = 15.3 Hz, 1H, CHaHb), 5.03 (AB, JAB = 15.3 Hz, 1H, CHaHb), 4.76
(dd, J = 14.5 Hz, J = 2.9 Hz, 1H, H-4b), 4.65 (dd, J = 14.5 Hz,
J = 6.3 Hz, 1H, H-4b), 4.52 (ddd, J = 7.2 Hz, J = 6.3 Hz, J = 2.9 Hz,
1H, H-3), 4.20 (dt, J = 8.8 Hz, J = 5.7 Hz, 1H, H-1), 4.10 (dt,
J = 7.3 Hz, J = 5.7 Hz, 1H, H-2), 1.35 (s, 3H, CH3), 1.24 (s, 3H, CH3);
13C NMR (151 MHz, CD3OD): d = 165.2 (s, C@O), 151.2 (s, C@O),
145.4 (s, N-CH@CH) 142.2, 136.3 (d, J = 5.6 Hz, Cipso), 136.2 (d,
J = 5.6 Hz, Cipso), 128.2, 128.2, 128.2, 127.9, 127.8 (Caromat), 125.1,
110.3 (s, C(CH3)2), 101.3 (s, NCH@CH), 77.0 (d, J = 8.4 Hz), 76.6 (d,
J = 8.6 Hz), 68.5 (d, J = 7.3 Hz, COP), 68.2 (d, J = 7.3 Hz, COP), 67.9
(d, J = 165.3 Hz, C-1), 52.0 (s, C-4), 42.5 (s, HC@CACH2AN), 25.9
(s, CH3), 25.7 (s, CH3); 31P NMR (CD3OD, 242 MHz):
d = 22.60 ppm. Anal. Calcd for C28H32N5O8P: C, 56.28; H, 5.40; N,
11.72. Found: C, 56.42; H, 5.21; N, 11.70.
4.2.30. (1S,2R,3S)-Dibenzyl 4-{[4-(8-chloro-1,3-dimethyl-2,6-
dioxopurin-7-yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-
trihydroxy-2,3-O-isopropylidenebutylphosphonate (1S,2R,3S)-
17i
Yield: 92%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
22.8 (c 1.09 in CHCl3); mp: 208–209 °C; IR (KBr):
2998, 2982, 1704, 1667, 1236, 1063, 778, 693 cmꢀ1
a]
D
m
= 3229, 3010,
1H NMR
;
(CDCl3, 600 MHz): d = 7.82 (s 1H, HC50), 7.387.26 (m, 10H,
2 ꢁ C6H5), 5.67 (AB, JAB = 14.5 Hz, 1H, CHaHb), 5.64 (AB, JAB = 14.5 Hz,
1H, CHaHb), 5.185.06 (m, 4H, 2 ꢁ POCH2Ph), 4.70 (dd, J = 14.5 Hz,
J = 2.9 Hz, 1H, H-4b), 4.64 (dd, J = 14.5 Hz, J = 5.7 Hz, 1H, H-4b),
4.50 (ddd, J = 8.0 Hz, J = 5.8 Hz, J = 2.9 Hz, 1H, H-3), 4.13 (dt,
J = 8.0 Hz, J = 5.2 Hz, 1H, H-1), 4.03 (dt, J = 7.6 Hz, J = 5.2 Hz, 1H,
H-2), 3.56 (s, 3H, NCH3), 3.41 (s, 3H, NCH3), 3.14 (dd, J = 13.0 Hz,
J = 5.2 Hz, 1H), 1.36 (s, 3H, CH3), 1.21 (s, 3H, CH3); 13C NMR
(151 MHz, CDCl3): d = 154.4 (s, C@O), 151.3, 147.4, 141.5, 139.1,
135.9 (d, J = 5.6 Hz, Cipso), 128.6, 128.6, 128.3, 128.0 (s, Caromat),
125.1, 110.3 (s, C(CH3)2), 107.4, 76.4 (d, J = 5.7 Hz), 76.3 (d,
J = 8.5 Hz), 68.7 (d, J = 6.9 Hz, COP), 68.6 (d, J = 6.9 Hz, COP), 68.5
(d, J = 162.0 Hz, C-1), 51.9 (s, C-4), 41.0 (s, HC@CACH2), 29.9
(s, CH3), 28.0 (s, CH3), 26.9 (s, CH3), 26.8 (s, CH3); 31P NMR (CDCl3,
242 MHz): d = 21.35 ppm. Anal. Calcd for C31H35ClN7O8P: C, 53.18;
H, 5.04; N, 14.01. Found: C, 53.15; H, 4.83; N, 13.90.
4.2.28. (1S,2R,3S)-Dibenzyl 4-{[4-(N4-acetylamino-2-
oxopyrimidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-
trihydroxy-2,3-O-isopropylidenebutylphosphonate (1S,2R,3S)-
17d
Yield: 89%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
18.7 (c 0.92 in DMSO); mp: 167–168 °C; IR (KBr):
3136, 3065, 2999, 1714, 1672, 1223, 1059, 966, 797, 742 cmꢀ1
a]
D
m
= 3395, 3306,
;
1H NMR (CDCl3, 600 MHz): d = 10.15 (br s, 1H, NH), 8.48 (s 1H,
HC50), 8.15 (d, J = 7.6 Hz, 1H, HC@CH), 7.51 (d, J = 7.6 Hz, HC@CH),
7.467.32 (m, 10H, 2 ꢁ C6H5), 6.64 (br s, 1H), 5.32–5.10 (m, 6H,
2 ꢁ POCH2Ph, HC@CCH2), 4.86 (dd, J = 14.1 Hz, J = 1,9 Hz, 1H, H-
4b), 4.60 (dd, J = 14,1 Hz, J = 8.8 Hz, 1H, H-4a), 4.52 (dt, J = 8.8 Hz,
J = 1.9 Hz, 1H, H-3), 4.184.11 (br m, 1H), 4.023.98 (m, 1H), 2.25
(s, 3H, NHC(O)CH3), 1.45 (s, 3H, CH3), 1.40 (s, 3H, CH3); 13C NMR
(151 MHz, DMSO-d6): d = 171.4 (s, C@O), 163.0, 155.5 (s, C@O),
150.5, 142.4, 137.1 (d, J = 5.6 Hz, Cipso), 137.0 (d, J = 5.6 Hz, Cipso),
128.9, 128.6, 128.6, 128.2 (Caromat), 125.4, 110.2 (s, C(CH3)2), 95.9,
77.5 (d, J = 8.3 Hz), 76.9 (d, J = 8.3 Hz), 68.0 (d, J = 6.5 Hz, POC),
67.9 (d, J = 162.6 Hz, CP), 67.5 (d, J = 6.5 Hz, POC), 52.3 (s, C-4),
44.9 (s, HC@CACH2AN), 27.3 (s, C-CH3), 27.2 (s, C-CH3), 24.8
(s,CH3C(O)); 31P NMR (CDCl3, 242 MHz): d = 23.14 ppm. Anal. Calcd
for C30H35N6O8P: C, 56.42; H, 5.52; N, 13.16. Found: C, 56.62; H,
5.53; N, 12.97.
4.2.31. (1S,2R,3R)-Dibenzyl 4-{[4-(6-amino-purin-9-yl)methyl]-
1H-1,2,3-triazol-1-yl}-1,2,3-trihydroxy-2,3-O-
isopropylidenebutylphosphonate (1S,2R,3R)-17a
Yield: 81%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+21.8 (c 1.43 in DMSO); mp: 100–102 °C; IR (KBr):
3185, 2987, 1646, 1602, 1219, 1053, 1009 cmꢀ1
a]
D
m
= 3324,
;
1H NMR
(600 MHz, CDCl3): d = 8.31 (s, 1H, HC@N), 8.02 (s, 1H, N@CH),
7.79 (s, 1H, HC50), 7.37–7.23 (m, 10H, 2 ꢁ C6H5), 6.48 (s, 2H,
NH2), 5.44 (s, 2H, HCACACH2), 5.19–5.08 (m, 4H, 2 ꢁ POCH2Ph),
4.99 (dd, J = 14.2 Hz, J = 1.5 Hz, 1H, H-4b), 4.54–4.50 (m, 2H),
4.42–4.36 (m, 1H), 4.20 (dt, J = 8.0 Hz, J = 6.1 Hz, 1H, H-1), 3.33
(br s, 1H, OH), 1.41 (s, 3H, CH3), 1.27 (s, 3H, CH3); 13C NMR
(151 MHz, CDCl3): d = 155.6, 152.7, 149.6, 141.9, 140.6, 136.1 (d,
J = 5.5 Hz, Cipso), 135.0 (d, J = 5.5 Hz, Cipso), 128.6, 128.5, 128.5,
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
11
128.5, 128.0, 128.0 (Caromat), 124.1, 119.1, 110.1 (s, C(CH3)2), 76.4
(d, J = 11.9 Hz, C-3), 75.6 (s, C-2), 68.5 (d, J = 6.8 Hz, COP), 68.4 (d,
J = 6.8 Hz, COP), 66.3 (d, J = 163.0 Hz, C-1), 50.9 (s, C-4), 38.6 (s,
HC@CACH2AN), 27.9 (s, CH3), 25.5 (s, CH3); 31P NMR (243 MHz,
CDCl3): d = 23.84 ppm. Anal. Calcd for C29H33N8O8P: C, 56.13; H,
5.36; N, 18.06. Found: C, 56.15; H, 5.34; N, 17.97.
(600 MHz, CDCl3): d = 8.30 (s, 1H, HC50), 8.08 (d, J = 7.6 Hz, 1H, H-
C=CH), 7.55 (d, J = 7.6 Hz, 1H, HC@CAH), 7.45–7.30 (m, 10H,
2 ꢁ C6H5), 6.70 (br s, 1H, NAH), 5.25 (dd, J = 14.1 Hz, J = 2.2 Hz,
1H, H-4b), 5.19–5.07 (m, 6H, 2 ꢁ POCH2Ph, HC@CACH2), 4.98–
4.95 (m, 2H, H-3, OH), 4.84 (dd, J = 14.1 Hz, J = 10.2 Hz, 1H, H-4a),
4.63 (ddd, J = 10.3 Hz, J = 7.7 Hz, J = 5.6 Hz, 1H, H-2), 4.20 (dt,
J = 10.3 Hz, J = 3.6 Hz, 1H, H-1), 2.26 (s, 3H, C(O)CH3), 1.49 (s, 3H,
CH3), 1.38 (s, 3H, CH3); 13C NMR (151 MHz, CDCl3): d = 171.6 (s,
C@O), 163.4, 155.5 (s, C@O), 149.4, 140.9, 136.3 (d, J = 5.5 Hz, Cipso),
136.1 (d, J = 5.5 Hz, Cipso), 128.5, 128.4, 127.8, 127.6 (Caromat), 125.4,
110.4 (s, C(CH3)2), 97.1, 77.1 (d, J = 14.5 Hz, C-3), 75.1 (s, C-2), 68.8
(d, J = 7.5 Hz, POC), 68.4 (d, J = 7.5 Hz, POC), 66.4 (d, J = 163.0 Hz, C-
1), 50.3 (s, C-4), 45.4 (s, HC@CACH2AN), 28.1 (s, CACH3), 25.8 (s,
CACH3), 24.7 (s,CH3C(O)); 31P NMR (243 MHz, CDCl3):
d = 25.31 ppm. Anal. Calcd for C30H35N6O8P: C, 56.42; H, 5.52; N,
13.16 Found: C, 56.33; H, 5.44; N, 13.02.
4.2.32. (1S,2R,3R)-Dibenzyl 4-{[4-(5-methyl-2,4-
dioxopyrimidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-
trihydroxy-2,3-O-isopropylidenebutylphosphonate (1S,2R,3R)-
17b
Yield: 89%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+10.2 (c 1.02 in CHCl3); mp: 126–127 °C; IR (KBr):
3063, 2988, 2819, 1680, 1456, 1218, 1051, 966 cmꢀ1
a]
D
m
= 3225,
;
1H NMR
(600 MHz, CDCl3): d = 8.94 (s, 1H, NH), 7.76 (s, 1H, HC50), 7.40–
7.29 (m, 11H, 2 ꢁ C6H5, HC@C), 5.18–5.07 (m, 4H, 2 ꢁ POCH2Ph),
5.00 (dd, J = 14.2 Hz, J = 2.6 Hz, 1H, H-4b), 4.98 (AB, JAB = 15.0 Hz,
1H, CHaHb), 4.94 (AB, JAB = 15.0 Hz, 1H, CHaHb), 4.58–4.52 (m, 1H,
H-3), 4.46 (dt, J = 8.7 Hz, J = 6.1 Hz, 1H, H-2), 4.42 (dd, J = 14.2 Hz,
J = 9.7 Hz, 1H, H-4a), 4.24 (br s, 1H, OH), 4, 13 (dt, J = 8.7 Hz,
J = 5.5 Hz, 1H, H-1), 1.63 (s, 3H, CH3), 1.42 (s, 3H, CH3), 1.25 (s,
3H, CH3); 13C NMR (151 MHz, CDCl3): d = 164.3 (s, C@O), 151.2
(s, C@O), 141.9 (s, HC@CACH3), 140.3, 136.1 (d, J = 5.6 Hz, Cipso),
136.0 (d, J = 5.6 Hz, Cipso), 128.6, 128.6, 128.6, 128.5, 128.1, 128.0
(Caromat), 124.7, 111.2 (s, C(CH3)2), 110.1 (s, HC@CCH3), 76.5 (d,
J = 12.3 Hz, C-3), 75.5 (s, C-2), 68.6 (d, J = 7.1 Hz, POC), 68.4 (d,
J = 7.1 Hz, POC), 66.5 (d, J = 162.2 Hz, PC), 50.9 (s, C-4), 42.8, 27.9,
25.5, 12.2; 31P NMR (243 MHz, CDCl3): d = 23.36 ppm. Anal. Calcd
for C29H34N5O8P: C, 56.95; H, 5.60; N, 11.45. Found: C, 57.10; H,
5.51; N, 11.33.
4.2.35. (1S,2R,3R)-Dibenzyl 4-{[4-(3,7-dimethyl-2,6-dioxopurin-
1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-trihydroxy-2,3-O-
isopropylidenebutylphosphonate (1S,2R,3R)-17g
Yield: 96%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+7.7 (c 0.95 in CHCl3); mp: 93–95 °C; IR (KBr):
2938, 1708, 1662, 1455, 1220, 1039, 997 cmꢀ1
a]
D
m
= 3418, 3287,
1H NMR
;
(600 MHz, CDCl3): d = 7.78 (s, 1H, HC50), 7.48 (s, 1H, N = CHAN),
7.38–7.21 (m, 10H, 2 ꢁ C6H5), 5.41 (br s, 1H, OH), 5.30 (AB,
JAB = 14.5 Hz, 1H, CHaHb), 5.27 (AB, JAB = 14.5 Hz, 1H, CHaHb),
5.12–5.03 (m, 4H, 2 ꢁ POCH2Ph), 4.95 (dd, J = 14.2 Hz, J = 2.5 Hz,
1H, H-4b), 4.57–4.52 (m, 1H, H-3), 4.49 (dt, J = 9.1 Hz, J = 6.1 Hz,
1H, H-2), 4.36 (dd, J = 14.2 Hz, J = 9.6 Hz, 1H, H-4a), 4.17 (dt,
J = 9.1 Hz, J = 5.9 Hz, 1H, H-1), 3.93 (s, 3H, NACH3), 3.52 (s, 3H,
NACH3), 1.39 (s, 3H, CH3), 1.26 (s, 3H, CH3); 13C NMR (151 MHz,
CDCl3): d = 154.8 (s, C@O), 151.3 (s, C@O), 148.3, 143.3, 141.6,
136.1 (d, J = 6.3 Hz, Cipso), 136.0 (d, J = 6,3 Hz, Cipso), 128.6, 128.5,
128.5, 128.4, 128.0, 127.9 (Caromat), 124.4, 109.9 (s, C(CH3)2),
107.7, 76.5 (d, J = 12.4 Hz, C-3), 75.6 (s, C-2), 68.4 (d, J = 7.1 Hz,
COP), 68.3 (d, J = 6.9 Hz, COP), 66.5 (d, J = 161.8 Hz, C-1), 50.4 (s,
C-4), 36.0 (s, HC@CACH2), 33.6 (s, CH3), 29.7 (s, CH3), 27.9 (s,
CH3), 25.5 (s, CH3); 31P NMR (243 MHz, CDCl3): d = 23.73 ppm.
Anal. Calcd for C31H36N7O8P: C, 55.94; H, 5.45; N, 14.73 Found: C,
56.07; H, 5.20; N, 15.02.
4.2.33. (1S,2R,3R)-Dibenzyl 4-{[4-(2,4-dioxopyrimidin-1-
yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-trihydroxy-2,3-O-
isopropylidenebutylphosphonate (1S,2R,3R)-17c
Yield: 93%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+29.4 (c 1.18 in CHCl3); mp: 155–156 °C; IR (KBr):
3012, 2825, 1688, 1241, 1052 cmꢀ1 1H NMR (600 MHz, CDCl3):
a]
D
m
= 3221,
;
d = 9.23 (s, 1H, NH), 7.78 (s, 1H, HC50), 7.57 (d, J = 7.8 Hz, 1H,
HC@CAH), 7.40–7.33 (m, 10H, 2 ꢁ C6H5), 5.70 (d, J = 7.8 Hz, 1H,
HC@CAH), 5.18–5.08 (m, 5H, 2 ꢁ POCH2Ph, OH), 5.10 (AB,
JAB = 15.0 Hz, 1H, CHaHb), 4.90 (AB, JAB = 15.0 Hz, 1H, CHaHb), 4.98
(dd, J = 14.2 Hz, J = 2.5 Hz, 1H, H-4b), 4.58–4.52 (m, 1H, H-3), 4.46
(dt, J = 8.9 Hz, J = 6.2 Hz, 1H, H-2), 4.42 (dd, J = 14.2 Hz, J = 9.8 Hz,
1H, H-4a), 4,14 (dt, J = 8,9 Hz, J = 5,5 Hz, 1H, H-1), 1.44 (s, 3H,
CH3), 1.30 (s, 3H, CH3); 13C NMR (151 MHz, CDCl3): d = 164.0 (s,
C@O), 151.2 (s, C@O), 144.5 (s, NACH@CH), 141.6, 136.1 (d,
J = 6.3 Hz, Cipso), 136.0 (d, J = 6.3 Hz, Cipso), 128.6, 128.6, 128.5,
128.5, 128.1, 128.0 (Caromat), 124.8, 110.1 (s, C(CH3)2), 102.6 (s,
NCH=CH), 76.4 (d, J = 12.4 Hz, C-3), 75.5 (s, C-2), 68.6 (d,
J = 6.9 Hz, COP), 68.4 (d, J = 6.9 Hz, COP), 66.4 (d, J = 162.6 Hz, C-
1), 50.9 (s, C-4), 43.0 (s, HC@CACH2AN), 28.0 (s, CH3), 25.5 (s,
CH3); 31P NMR (243 MHz, CDCl3): d = 23.43 ppm. Anal. Calcd for
4.2.36. (1S,2R,3R)-Dibenzyl 4-{[4-(1,3-dimethyl-2,6-dioxopurin-
7-yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-trihydroxy-2,3-O-
isopropylidenebutylphosphonate (1S,2R,3R)-17h
Yield: 94%; colorless oil [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+122.1 (c 1.70 in CHCl3); IR (film):
1664, 1222, 1029, 997, 745, 644 cmꢀ1
a]
D
m
;
= 3097, 2948, 2865, 1707,
1H NMR (600 MHz, CDCl3):
d = 7.91 (s, 1H, HC50), 7.83 (s, 1H, N@CHAN), 7.38–7.30 (m, 10H,
2 ꢁ C6H5), 5.63 (AB, JAB = 15.0 Hz, 1H, CHaHb), 5.60 (AB, JAB = 15.0 -
Hz, 1H, CHaHb), 5.17–5.06 (m, 4H, 2 ꢁ POCH2Ph), 4.96 (dd,
J = 14.2 Hz, J = 2.7 Hz, 1H, H-4b), 4.55–4.52 (m, 1H, H-3), 4.45 (dt,
J = 8.6 Hz, J = 6.1 Hz, 1H, H-2), 4.38 (dd, J = 14.2 Hz, J = 9.7 Hz, 1H,
H-4a), 4.11 (dt, J = 8.7 Hz, J = 5.6 Hz, 1H, H-1), 3.66 (br s, 1H, OH),
3.59 (s, 3H, NACH3), 3.43 (s, 3H, NACH3), 1.45 (s, 3H, CH3), 1.30
(s, 3H, CH3); 13C NMR (151 MHz, CDCl3): d = 155.4 (s, C@O),
151.6 (s, C@O), 148.9, 141.9, 141.5, 135.9 (d, J = 5.9 Hz, Cipso),
135.9 (d, J = 5.9 Hz, Cipso), 128.6, 128.6, 128.6, 128.0, 127.9 (Caromat),
124.7, 110.1 (s, C(CH3)2), 106.5, 76.4 (d, J = 12.2 Hz, C-3), 75.5 (s, C-
2), 68.6 (d, J = 7.3 Hz, COP), 68.4 (d, J = 7.3 Hz, COP), 65.5 (d,
J = 162.0 Hz, CP), 50.8 (s, C-4), 41.5, 29.8 (s, CH3), 27.9 (s, CH3),
27.9 (s, CH3), 25.5 (s, CH3); 31P NMR (242 MHz, CDCl3):
d = 23.14 ppm. Anal. Calcd for C31H36N7O8P: C, 55.94; H, 5.45; N,
14.73 Found: C, 55.75; H, 5.68; N, 14.55.
C28H32N5O8P: C, 56.28; H, 5.40; N, 11.72. Found: C, 56.42; H,
5.23; N, 11.91.
4.2.34. (1S,2R,3R)-Dibenzyl 4-{[4-(N4-acetylamino-2-
oxopyrimidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-
trihydroxy-2,3-O-isopropylidenebutylphosphonate (1S,2R,3R)-
17d
Yield: 95%; white powder [chromatographed on a silica gel col-
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+30.7 (c 0.75 in CHCl3); mp: 107–108 °C; IR (KBr):
2986, 2936, 1721, 1663, 1494, 1219, 1051, 966 cmꢀ1
a]
D
m
= 3227,
;
1H NMR
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

12
I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
4.2.37. (1S,2R,3R)-Dibenzyl 4-{[4-(8-chloro-1,3-dimethyl-2,6-
dioxopurin-7-yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2,3-
trihydroxy-2,3-O-isopropylidenebutylphosphonate (1S,2R,3R)-
17i
J = 9.0 Hz, C-3), 43.4; 31P NMR (121.5 MHz, CD3OD):
d = 21.53 ppm. Anal. Calcd for C17H18N5O8P ꢁ H2O: C, 43.50; H,
4.30; N, 14.92. Found: C, 43.72; H, 4.55; N, 15.16.
Yield: 94%; white powder [chromatographed on a silica gel col-
4.4. Antiviral activity assays
20
umn with chloroform–methanol (50:1, 20:1, 10:1, v/v)]; [
+17.0 (c 1.37 in CHCl3); mp: 194–196 °C; IR (KBr):
2992, 2954, 2895, 1706, 1663, 1541, 1378, 1217, 997 cmꢀ1
a]
D
m
= 3279,
1H
The compounds were evaluated against the following viruses:
herpes simplex virus type
;
1 (HSV-1) strain KOS, thymidine
NMR (600 MHz, CDCl3): d = 7.89 (s, 1H, HC50), 7.37–7.29 (m, 10H,
2 ꢁ C6H5), 5.65 (AB, JAB = 15.2 Hz, 1H, CHaHb), 5.62 (AB, JAB = 15.2 -
Hz, 1H, CHaHb), 5.15–5.04 (m, 4H, 2 ꢁ POCH2Ph), 4.96 (dd,
J = 14.2 Hz, J = 2.5 Hz, 1H, H-4b), 4.91 (br s, 1H, OH), 4.57–4.52
(m, 1H, H-3), 4.49 (dt, J = 8.9 Hz, J = 6.4 Hz, 1H, H-2), 4.37 (dd,
J = 14.2 Hz, J = 9.8 Hz, 1H, H-4a), 4.12 (dt, J = 9.1 Hz, J = 5.8 Hz, 1H,
H-1), 3.54 (s, 3H, NACH3), 3.39 (s, 3H, NACH3), 1.41 (s, 3H, CH3),
1.28 (s, 3H, CH3); 13C NMR (151 MHz, CDCl3): d = 154.5 (s, C@O),
159.3, 147.4 (s, C@O), 141.5, 139.1, 135.9 (Cipso), 128.6, 128.6,
128.5, 128.1, 127.9 (s, Caromat), 124.7, 110.0 (s, C(CH3)2), 107.4,
76.3 (d, J = 12,2 Hz, C-3), 75.6 (s, C-2), 68.6 (d, J = 7.3 Hz, COP),
68.4 (d, J = 7.3 Hz, COP), 66.5 (d, J = 161.6 Hz, C-1), 50.6 (s, C-4),
41.0 (s, HC@CACH2), 29.8 (s, CH3), 28.0 (s, CH3), 27.9 (s, CH3),
25.5 (s, CH3); 31P NMR (243 MHz, CDCl3): d = 23.46 ppm. Anal.
Calcd for C31H35ClN7O8P: C, 53.18; H, 5.04; N, 14.01. Found: C,
53.28; H, 4.81; N, 14.28.
kinase-deficient (TKꢀ) HSV-1 KOS strain resistant to ACV (ACVr),
herpes simplex virus type 2 (HSV-2) strains Lyons and G, vari-
cella-zoster virus (VZV) strain Oka, TKꢀ VZV strain 07ꢀ1, human
cytomegalovirus (HCMV) strains AD-169 and Davis, vaccinia virus
Lederle strain, respiratory syncytial virus (RSV) strain Long, vesicu-
lar stomatitis virus (VSV), Coxsackie B4, Parainfluenza 3, Influenza
virus A (subtypes H1N1, H3N2), influenza virus B, Reovirus-1, Sind-
bis, Reovirus-1, Punta Toro, human immunodeficiency virus type 1
strain IIIB and human immunodeficiency virus type 2 strain ROD.
The antiviral, other than anti-HIV, assays were based on inhibition
of virus-induced cytopathicity or plaque formation in human
embryonic lung (HEL) fibroblasts, African green monkey cells
(Vero), human epithelial cells (HeLa) or Madin-Darby canine kidney
cells (MDCK). Confluent cell cultures 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) (VZV) in the presence of varying concentrations of the
test compounds. Viral cytopathicity or plaque formation was
recorded as soon as it reached completion in the control virus-
infected cell cultures that were not treated with the test com-
pounds. Antiviral activity was expressed as the EC50 or compound
concentration required to reduce virus-induced cytopathogenicity
or viral plaque formation by 50%.
4.3. Synthesis of phosphonic acid 21b and 21k (general
procedure)
The dibenzyl phosphonates (1S,2S)-16b and (1S,2S)-16k
(1 mmol) were dissolved in methanol (10 mL) and water (2 mL)
and 10% Pd–C (10 mg) was added. The suspension was stirred
under hydrogen atmosphere at room temperature for 48 h. The
catalyst was filtered through a layer of Celite and the aqueous solu-
tion was concentrated in vacuo to give pure phosphonic acids 21b
and 21k.
4.5. Anti-HIV activity assays
Inhibition of HIV-1(IIIB)- and HIV-2(ROD)-induced cytopathicity
in CEM cell cultures was measured in microtiter 96-well plates
containing ꢃ3 ꢁ 105 CEM cells/mL infected with 100 CCID50 of
HIV per milliliter and containing appropriate dilutions of the test
compounds. After 4–5 days of incubation at 37 °C in a CO2-con-
trolled humidified atmosphere, CEM giant (syncytium) cell forma-
tion was examined microscopically. The EC50 (50% effective
concentration) was defined as the compound concentration
required to inhibit HIV-induced giant cell formation by 50%.
4.3.1. (1S,2S)-3-{4-[(5-Methyl-2,4-dioxopyrimidin-1-yl)methyl]-
1H-1,2,3-triazol-1-yl}-1,2-dihydroxypropylphosphonic acid
(1S,2S)-21b
20
Yield: 87%; white powder; [
240–243 °C; IR (KBr):
1020 cmꢀ1 1H NMR (300 MHz, CD3OD): d = 8.05 (s, 1H, HC50),
a]
18.3 (c 1.85 in DMSO); mp:
D
m
= 3290, 2833, 1680, 1614, 1225,
;
7.55 (d, J = 1.1 Hz, 1H, CH3C@CH), 5.02 (s, 2H, CH2), 4.67 (dd,
J = 14.4 Hz, J = 3.8 Hz, 1H, H-3a), 4.52 (dd, J = 14.4 Hz, J = 9.6 Hz,
1H, H-3b), 4.32–4.25 (m, 1H, H-2), 3.76 (dd, J = 10.8 Hz, J = 4.1 Hz,
1H, H-1), 1.84 (d, J = 1.1 Hz, 3H, CH3); 13C NMR (151 MHz, DMSO-
d6): d = 164.7, 151.2, 142.5, 141.6, 124.8, 109.3, 70.6, 68.6 (d,
J = 164.2 Hz, PC), 53.2 (d, J = 5.6 Hz), 42.6, 12.4; 31P NMR
(121.5 MHz, CD3OD): d = 18.47 ppm. Anal. Calcd for C11H16N5O7
P ꢁ H2O: C, 34.84; H, 4.78; N, 18.47. Found: C, 35.02; H, 5.00; N,
14.20.
4.6. Cytostatic activity assays
All assays were performed in 96-well microtiter plates. To each
well were added (5–7.5) ꢁ 104 tumor cells and a given amount of
the test compound. The cells were allowed to proliferate for 48 h
(murine leukemia L1210 cells) or 72 h (human lymphocytic CEM
and human cervix carcinoma HeLa cells) at 37 °C in a humidified
CO2-controlled atmosphere. At the end of the incubation period,
the cells were counted in a Coulter counter. The IC50 (50% inhibi-
tory concentration) was defined as the concentration of the com-
pound that inhibited cell proliferation by 50%.
4.3.2. (1S,2S)-3-{4-[(3-benzoyl-2,4-dioxopyrimidin-1-
yl)methyl]-1H-1,2,3-triazol-1-yl}-1,2-
dihydroxypropylphosphonic acid (1S,2S)-21k
20
Yield: 89%; white powder; [
130–132 °C; IR (KBr):
762, 689 cmꢀ1 1H NMR (300 MHz, CD3OD): d = 8.03 (s, 1H, HC50),
a
]
17.6 (c 3.42 in DMSO); mp:
D
m
= 3323, 2830, 1701, 1698,1230, 1025,
Acknowledgments
;
7.97–7.95 (m, 2H, Haromat), 7.85 (d, J = 8.0 Hz, 1H, HC@CH), 7.75–
7.68 (m, 1H, Haromat), 7.60–7.54 (m, 2H, Haromat), 5.84 (d,
J = 8.0 Hz, 1H, HC@CH), 5.15 (s, 2H, CH2), 4.72 (dd, J = 13.9 Hz,
J = 3.8 Hz, 1H, H-3a), 4.50 (dd, J = 13.9 Hz, J = 8.9 Hz, 1H, H-3b),
4.31–4.22 (m, 1H, H-2), 3.78 (dd, J = 10.5 Hz, J = 4.1 Hz, 1H, H-1);
13C NMR (151 MHz, CD3OD): d = 170.0 (s, C@O), 162.7 (s, C@O),
149.9 (s, C@O), 147.0, 141.8, 136.0, 131.6, 130.5, 125.0, 101.4,
70.6 (d, J = 4.4 Hz, C-2), 68.9 (d, J = 157.7 Hz, PC), 53.3 (d,
The authors wish to express their gratitude to Mrs. Małgorzata
Pluskota, Mrs. Leentje Persoons, Mrs. Frieda De Meyer, Mrs. Lies
Van den Heurck, Mr. Steven Carmans, Mrs. Anita Camps and Mrs.
Lizette van Berckelaer for excellent technical assistance. This work
was supported by the National Science Centre under Decision DEC-
2011/01/D/NZ4/01276. The virological part of this work was sup-
ported by the KU Leuven (GOA no. 10/014).
Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020

I. E. Głowacka et al. / Bioorg. Med. Chem. xxx (2014) xxx–xxx
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Please cite this article in press as: Głowacka, I. E.; et al. Bioorg. Med. Chem. (2014), http://dx.doi.org/10.1016/j.bmc.2014.05.020