Synthesis of Cyclic and Acyclic Nucleoside Phosphonates and Sulfonamides Derived from 6-(Thiophen-2-yl)-7-fluoro-7-deazapurine

Article abstract of DOI:10.1002/ejoc.201900509

Ribonuclosides derived from 6-hetaryl-7-dezapurines are potent cytostatics, but their mechanism of action is unknown. Here we designed and synthesized a series of cyclic and acyclic nucleoside phosphonates, as well as carboxy, cyano, sulfo, and sulfonamide acyclic analogues derived from 6-thiophen-2-yl-7-deazapurine and 7-fluoro-6-thiophen-2-yl-7-deazapurine as ribonucleoside monophosphate mimics. None of these analogues exerted significant cytotoxic and antiviral activity.

Full text of DOI:10.1002/ejoc.201900509

A Journal of
Accepted Article
Title: Synthesis of Cyclic and Acyclic Nucleoside Phosphonates
and Sulfonamides Derived from 6-(Thiophen-2-yl)-7-fluoro-7-
deazapurine
Authors: Vincent Malnuit, Sabina Smolen, Michal Tichy, Lenka Postova
Slavetinska, and Michal Hocek
This manuscript has been accepted after peer review and appears as an
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To be cited as: Eur. J. Org. Chem. 10.1002/ejoc.201900509
Link to VoR: http://dx.doi.org/10.1002/ejoc.201900509
Supported by

European Journal of Organic Chemistry
10.1002/ejoc.201900509
Synthesis of Cyclic and Acyclic Nucleoside Phosphonates and Sulfonamides Derived from
-(Thiophen-2-yl)-7-fluoro-7-deazapurine
6
a
a
a
a
Vincent Malnuit, Sabina Smoleń, Michal Tichý, Lenka Poštová Slavětínská, Michal
Hoceka,b,
*
a Dr. V. Malnuit, Dr. S. Smoleń, Dr. M. Tichý, Dr. L. Poštová Slavětínská, Prof. Dr. M. Hocek
Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nam. 2, CZ-
16610 Prague 6, Czech Republic.
b Prof. Dr. M. Hocek
Department of Organic Chemistry, Faculty of Science, Charles University in Prague, Hlavova 8, CZ-
1
*
2843 Prague 2, Czech Republic.
Corresponding author: E-mail: hocek@uochb.cas.cz
http://hocekgroup.uochb.cas.cz/index.html
Abstract:
Ribonuclosides derives from 6-hetaryl-7-dezapurines are potent cytostatics but their
mechanism of action is unknown. Here we designed and synthesized a series of cyclic and
acyclic nucleoside phosphonates, as well as carboxy, cyano, sulfo and sulfonamide acyclic
analogues derived from 6-thiophen-2-yl-7-deazapurine and 7-fluoro-6-thiophen-2-yl-7-
deazapurine as ribonucleoside monophosphate mimics. None of these analogues exerted
significant cytotoxic and antiviral activity.
1
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
Introduction:
Recently, we discovered two classes of potent and selective 7-deazapurine nucleoside
cytostatics – 7-hetaryl-7-deazaadenosines represented by the most active compound AB-61,1
2
and 6-hetaryl-7-deazapurine ribonucleosides bearing hydrogen or fluorine in position 7 with
nucleosides 1 and 2 being the most active in the series (Figure 1). Whilst the mechanism of
action of AB-61 was studied in detail and involves activation of nucleosides to triphosphate,
3
incorporation to DNA and causing double-strand breaks and apoptosis, much less is known
about the mode of action of the other class of nucleosides, 6-hetaryl derivatives 1 and 2.
2
Previously, it was shown that both nucleosides are phosphorylated by adenosine kinases
(ADKs) to their monophosphates and triphosphates, which then inhibit RNA polymerase,
however, this might not be the only target and mechanism.
4
Acyclic nucleoside phosphonates developed by A. Holý and E. De Clercq are clinically used
antivirals against HIV and hepatitis B virus (HBV). They overcome the first phosphorylation
by nucleoside kinases, which is usually the limiting step in activation of nucleoside antivirals
and cytostatics. The replacement of the phosphate ester, which is prone to both chemical and
enzymatic hydrolysis, with phosphonate and changing the labile nucleosidic bond (cleavable
by purine or pyrimidine nucleoside phosphorylases) by acyclic functionalized alkyl chain
stabilizes the molecules against catabolic degradation. Recently, also other functional groups
were used as stable mimics of phosphate, sulfamates and sulfonamides being particularly
5
successful in antibacterial nucleotide analogues. Therefore, we designed a series of acyclic and
cyclic phosphonates, sulfonamides and other related derivatives (including sulfonates and
carboxylates) derived from 7-deazapurine bearing thiophen-2-yl group in position 6 in order to
make stable nucleoside monophosphate analogues and to find out whether the first
phosphorylation of compounds 2-3 may be the crucial step in their activation.
2
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
Figure 1. Previously prepared 7-deazapurine nucleoside cytostatics and examples of biologically active
phosphonate and sulfonamide analogues
Chemistry:
6
The first target molecules were cyclic nucleoside phosphonates, 5´-O-phosphonomethyl ethers
of the parent nucleosides 1 and 2, which contain stable analogue of 5’-monophosphate moiety
but the linkage is one single bond longer than in matural nucleotide. 2’,3’-Isopropylidene
protected key intermediates 4 and 5 were prepared either by desilylation of the known protected
2
nucleoside 3 with tetra-n-butylammonium fluoride (TBAF) or by acetal formation in free
2
7
nucleoside 2. Compounds 4 and 5 were then alkylated by tosylate 6 giving nucleoside
phosphonates 7 and 8 in acceptable yields (40% and 25%, respectively). Since nucleosides are
8
known to be sensitive to hydrobromic acid, which is inherently present in trimethylsilyl
9
bromide (TMSBr), common phosphonate deprotection reagent for phosphonate esters, we
1
0
decided to use TMSBr in combination with basic 2,6-lutidine followed by treatment with
trifluoroacetic acid (TFA) to get the desired free nucleoside phosphonates 9 and 10 in good
yields (56% and 73%, respectively, Scheme 1).
3
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
Scheme 1. Reagents and conditions: i) 2,2´-dimethoxypropane, p-toluenesulfonic acid (PTSA), acetone, 22 °C,
h; ii) TBAF 1 M solution in THF, 22 °C, 20 min.; iii) NaH, DMF, –20 °C to 22 °C, 1–5 h; iv) 1. TMSBr, 2,6-
lutidin, CH CN, 22 °C, 1–3 days; 2. TFA, 22 °C, 30 min.
1
3
The synthesis of acyclic nucleoside phosphonates (Scheme 2) started with an alkylation
step in order to introduce the phosphonoalkoxyalkyl groups. We decided to prepare
phosphonomethoxyethyl derivatives (analogous to Adefovir)4,11 as well as homologous
phosphonoethoxyethyl derivatives (which were found to inhibit phosphoribosyl transferases in
1
2
hypoxanthine and guanine series) . The commercial 6-chloro-7-deazapurine 11 or 6-chloro-7-
1
3
fluoro-7-deazapurine 12 were deprotonated by sodium hydride in DMF and alkylated with
commercially available chlorides bearing an ethoxymethyl or ethoxyethyl linkers and ethyl or
isopropyl protecting groups on phosphonate moiety to give acyclic nucleoside phosphonates
1
3–16. As the separation of the target compounds from an excess of the alkylating agent is
almost impossible at this step, the crude materials were directly used for the subsequent
introduction of thiophen-2-yl group. The aqueous Suzuki-Miyaura reaction in presence of
Pd(OAc)
2
, triphenylphospane-3,3’,3”-trisulfonate (TPPTS) and Na
2
CO
3
in a water/acetonitrile
1
4
2
:1 at 100 °C gave 6-(thiophen-2-yl)-7-deazapurine derivatives 17–20 (Scheme 2). The final
phosphonic acids 21–24 were obtained by deprotection of compounds 17–20 with trimethylsilyl
4
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
bromide and 2,6-lutidin in acetonitrile at room temperature with moderate but acceptable
overall yields for the three-step synthesis from 7-deazapurines 11 and 12 (32%, 16%, 47% and
3
8%, respectively).
Scheme 2. Reagents and conditions: i) 1. NaH, DMF, 22 °C, 30 min; 2. (RO)
RO) P(O)CH CH OCH CH Cl, 80 °C, 2 h; ii) Pd(OAc) , TPPTS, Na CO , H O/CH
TMSBr, 2,6-lutidine, CH CN, 22 °C, 3 days.
2
P(O)CH
2 2 2
OCH CH Cl or
(
2
2
2
2
2
2
2
3
2
3
CN 2:1, 100 °C, 1 h; iii)
3
Preparation of branched phosphonates, derived from antiviral 3-hydroxy-2-
1
5
phosphonomethoxyethyl nucleotide analogues, e. g. Cidofovir, (Scheme 3) was realized by
9
known double alkylation strategy. The initial step was the opening of a commercially available
trityl-protected glycidol 25 by deprotonated 7-deazapurines 11 and 12, followed first by Stille
cross-coupling with 2-tributylstannylthiophene and then by alkylation of the resulting alcohols
7
2
6 and 27 by freshly prepared and dried tosylate 6 to give the protected phosphonates 30 and
5
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
3
1 (42% and 72%, respectively, Scheme 3). The final deprotection was performed in two steps
phosphonate moieties were deprotected first by TMSBr and 2,6-lutidine (as above) followed
-
by detritylation by trifluoroacetic acid to furnish phosphonic acids 32 and 33 in moderate
overall yields (53% and 52%, respectively, Scheme 3). Dihydroxypropyl derivatives 34 and 35,
analogues of antiviral DHPA,16 were obtained from 28 and 29 by direct detritylation in
trifluoroacetic acid in moderate to good yields (61% and 80%, respectively, Scheme 3).
Scheme 3. Reagents and conditions: i) Cs
2
CO
3
, DMF, 120 °C, 2 h; ii) 2-tributylstannylthiophene, Pd(PPh
3
)
2
Cl ,
2
DMF, 100 °C, 1 h; iii) NaH, DMF, –20 °C to 22 °C, 1 h; iv) 1. TMSBr, 2,6-lutidine, CH
TFA, 22 °C, 30 min; v) TFA, 22 °C, 15 min.
3
CN, 22 °C, 3 days; 2.
Next, we designed a series of acyclic nucleotide analogues, in which the sugar was replaced by
an aliphatic ether moiety decorated with various functional groups (carboxyl, nitrile, sulfo and
sulfonamide) to mimic the phosphate group. The synthetic strategy for these molecules
1
3
involved alkylation of 6-chloro-7-fluoro-7-deazapurine 12 followed by the Stille or Suzuki
cross-coupling reactions at the position 6 in order to introduce thiophen-2-yl group and in some
cases an additional deprotection step.
6
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
First, the tosylated alkylation agents bearing carboxyl and nitrile group were prepared
(Scheme 4). Desired tert-butyl 3-(2-hydroxyethoxy)propanoate (36) was synthesized according
to literature procedure from ethylene glycol and tert-butyl acrylate.17 Analogous 3-(2-
hydroxyethyloxy)propanenitrile (37) was prepared in similar manner in excellent 93% yield,
but using potassium hydroxide as base. Reaction of compounds 36 and 37 with tosyl chloride
in presence of Et
3
N and N,N-dimethylpyridin-4-amine (DMAP) afforded the desired tosylates
3
8 and 39 in 66% and 74% yield, respectively (Scheme 4).
Scheme 4. Reagents and conditions: i) Na, THF, 0 ˚C to 22 °C, 16 h; ii) KOH, THF, 0 ˚C to 22 °C, 16 h; iii) TosCl,
Et N, DMAP, DCM, 0 ˚C to 22 °C, 16 h.
3
Tosylates 38 and 39 were then used for alkylation of 6-chloro-7-fluoro-7-deazapurine 12 to
1
8
give new 7-deazapurine derivatives 40 (47%) and 41 (68%). In the next step, thiophen-2-yl
group was introduced into position 6 by Stille or Suzuki-Miyaura reactions. Thiophen-2-yl
derivative 43 was prepared from 41 by the Stille cross-coupling with 2-tributylstannylthiophene
catalyzed by PdCl
2
(PPh
3
) in 84% yield (Scheme 5). Unfortunately, in case of derivative 40,
2
using of the same conditions led to formation of inseparable mixture of the desired 2-thienyl
product 42 contaminated with 20% of an analogue dehalogenated at position 7. As lowering the
catalyst loading to 1% did not prevent the dehalogenation, the desired ester 42 was prepared by
1
4
the aqueous Suzuki-Miyaura cross-coupling reaction in excellent 95% yield. Final cleavage
of the tert-butyl group by treatment with trifluorocetic acid in presence of anisole furnished
target acid 44 in good yield (80%, Scheme 5).
7
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
Scheme 5. Reagents and conditions: i) 1. NaH, DMF, 0 ˚C, 10 min; 2. 38 or 39, 60 ˚C, 2 h; ii) 2-thienylboronic
acid, Pd(OAc) , TPPTS, Na CO , MeCN/H O, 100 ˚C, 1 h; iii) 2-tributylstannyl thiophene, PdCl (PPh , DMF,
00 °C, 1 h; iv) TFA, anisole, DCM, 22 °C, 3 h.
2
2
3
2
2
3 2
)
1
Sulfonic acids and sulfonamides were the next target compounds. The sulfonic acid 47 was
synthesized from deazapurine 12 by its alkylation by commercially available bis(2-
bromoethyl)ether followed by Stille reaction to give derivative 46 in good yield (61% after two
1
9
steps, Scheme 6). The desired sulfonic acid 47 was prepared by Strecker sulfite alkylation of
bromo derivative 46 with sodium sulfate in the mixture of water/ethanol for 4 h followed by
+
ion exchange chromatography (Dowex 50W, H form) to convert the obtained sodium sulfonate
to the free sulfonic acid.
Scheme 6. Reagents and conditions: i) 1. NaH, DMF, 0 ˚C, 10 min; 2. bis(2-bromoethyl)ether, 60 ˚C, 2 h; ii) 2-
2 3 2 2 3 2
tributylstannylthiophene, PdCl (PPh ) , DMF, 100 ˚C, 1 h; iii) 1. Na SO , EtOH/H O, reflux, 4 h; 2. DOWEX
+
5
0W, H form.
Next goal was to prepare a series of sulfonamide derivatives, which was attempted by a classical
approach involving reaction of a key-intermediate sulfonyl chloride 48 with ammonia or
amines. However, all attempts to prepare corresponding sulfonyl chloride 48 failed mostly
because of rapid decomposition of sulfonic acid 47 under harsh acidic conditions. Reaction with
thionyl chloride unexpectedly gave only an undesired product which was identified as
chloroderivative 49 but was only partially characterized due to limited stability (Scheme 7).
8
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
2
Scheme 7. Reagents and conditions: i) SOCl , toluene, reflux, 16 h.
Therefore, we were forced to change the strategy and first prepare the corresponding ether
moiety bearing an appropriate sulfonamide group and then use it for alkylation of deazapurine
1
2. The best approach to obtain sulfonyl chloride 50 turned to be the known two step
procedure.20 Sulfonyl chloride 50 was prepared from bis(2-bromoethyl)ether and S-
alkylisothiourea chloride via the N-chlorosuccinimide chlorosulfonation. Due to its instability,
sulfonyl chloride 50 was always used immediately for the next step, nucleophilic substitution
with ammonia and several amines (piperidine, morpholine, 1-Boc-piperazine) furnishing
sulfonamides 51–54 in moderate yields (Scheme 8).
Scheme 8. Reagents and conditions: i) 1. thiourea, EtOH, reflux, 30 min; 2. NCS, MeCN/2 M HCl, –10 ˚C to 22
3 .
°C, 1.5 h; ii) NH (aq ), 1,4-dioxane/MeCN, 0 ˚C to 22 °C, 1.5 h; iii) amine, DCM, 0 ˚C to 22 °C, 2 h.
The reaction of 6-chloro-7-fluoro-7-deazapurine 12 with suitable building blocks 51–54 under
previously established conditions (NaH, DMF, 80 ˚C) gave intermediate sulfonamides 55–58
in good to moderate yields (27–74%, Scheme 9). Synthesis of corresponding thiophen-2-yl
derivatives 59–62 was performed by the aqueous Suzuki-Miyaura cross-coupling reaction.
N-Boc protected piperazine derivative 62 was treated by TFA in DCM with catalytic amount
of anisole to give sulfonamide 63 in excellent 94% yield.
9
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
Scheme 9. Reagents and conditions: i) 1. NaH, DMF, 0 ˚C, 10 min; 2. 55–58, 80 ˚C, 3 h; ii) thiophen-2-ylboronic
acid, Pd(OAc) , TPPTS, Na CO , MeCN/H O, 100 ˚C, 1 h; iii) TFA, anisole, DCM, 22 °C, 2 h.
2
2
3
2
All the title compounds were submitted for screening of biological activities. They were tested
2
1
for cytotoxic activity on a panel of leukemia (CCRF-CEM, CEM-DNR, K562, and K562-
TAX) and cancer cell lines (A549, HCT116 and HCT116p53–/), for antiviral activity (hepatitis
2
2
23
24
C virus, dengue, HIV, respiratory syncytial virus, influenza, coxsackie and herpes viruses)
and for antibacterial activity (Staphylococcus aureus 4591, Enterococcus faecium 419/ANA,
Enterococcus faecalis CCM 4224, Escherichia coli CE5556, Pseudomonas aeruginosa R,
2
5
Candida albicans CCM 8161 and Staphylococcus aureus CCM 3953). However, all the final
compounds were found inactive (IC50 >50 µM) in these assays, suggesting that the ribose
moiety is crucial for cytotoxic activity of this class of nucleosides and that installing of a stable
phosphate surrogate does not increase the activity. This is in agreement with our previous works
2
6
27
reporting that the sugar modified nucleosides as well as phosphate prodrugs were less active
than the parent ribonucleosides.
Conclusion
We successfully prepared a series of cyclic and acyclic nucleoside phosphonates derived from
6
-(thiophen-2-yl)-7-deazapurine or 6-(thiophen-2-yl)-7-fluoro-7-deazapurine bases as
analogues of potent cytostatic ribonucleosides. We also synthesized a series of acyclic
1
0
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
analogues where the ribose moiety was replaced with ethoxyethyl linker bearing a polar groups
i.e. carboxyl, cyano, sulfo and sulfonamides. None of the title compounds exerted any
significant cytotoxic, antiviral or antibacterial effect. Despite the lack of activity, these results
are important for SAR and future considerations of the mechanism of action of the parent
cytostatic ribonucleosides.
Experimental
General remarks
All reactions with organometallic reagents as well as all palladium catalyzed reactions were
performed in flame-dried glassware under argon atmosphere. THF was always freshly distilled
from sodium/benzophenone. Nucleosides 2a and 3 and 6-chloro-7-fluoro-7-deazapurine (12)28
2
7
and tosylate 6 were prepared as described in literature. 6-Chloro-7-deazapurine, diethyl [(2-
chloroethoxy)methyl]phosphonate, diisopropyl [(2-chloroethoxy)methyl]phosphonate, (S)-2-
((trityloxy)methyl)oxirane and all other solvents and reagents were purchased from commercial
suppliers and used as received. Reactions were monitored by thin layer chromatography (TLC)
on TLC Silica gel 60 F254 (Merck) and detected by UV (254 nm) or by solution of 4-
anisaldehyde in ethanol and 10% of sulphuric acid. Melting points were determined on a Stuart
SMP40 melting point apparatus and are uncorrected. Optical rotations were measured in DMSO
on Autopol IV polarimeter (Rudolph Research Analytical), [훼] 2퐷 0 values are given in 10-1
2
–1
deg·cm ·g . IR spectra were recorded on Bruker Alpha FT-IR spectrometer using attenuated
total reflection (ATR). NMR spectra were measured on Bruker Avance 400 MHz spectrometer
1
13
(
400.1 MHz for H and 100.6 MHz for C) or Bruker Avance 500 MHz spectrometer (499.8
MHz for H, 125.7 MHz for 13C and 31P at 202.3 MHz) or Bruker Avance 600 MHz
1
1
13
spectrometer (600.1 MHz for H and 150.9 MHz for C) in DMSO-d6 (referenced to the
1
13
residual solvent signal, [δ ( H) = 2.50 ppm, δ ( C) = 39.7 ppm]) or in CDCl (referenced to the
3
1
13
residual solvent signal, [δ ( H) = 7.26 ppm, δ ( C) = 77.0 ppm]). Chemical shifts are given in
ppm (δ-scale), coupling constants (J) in Hz. Complete assignment of all NMR signals was
performed using a combination of H,H-COSY, H,H-ROESY, H,C-HSQC and H,C-HMBC
experiments. Low resolution mass spectra were measured on LCQ Fleet (Thermo Fisher
Scientific) using electrospray ionization (ESI). High resolution mass spectra were measured on
LTQ Orbitrap XL (Thermo Fisher Scientific). All mass spectra were acquired by the MS service
at IOCB. Elemental analyses were performed by the Analytical laboratory at IOCB on PE 2400
Series II CHNS/O Analyzer (Perkin Elmer, USA) – C,H,N; other elements were determined on
1
1
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
SPECTRO iQ II (Spectro Analytical Instruments, Germany). HPLC analysis was performed on
a Waters modular HPLC system on a column packed with 10 μm C18 reversed phase
(
Phenomenex, Luna C18 (2) 100 Å). Methods: A: linear gradient 0 to 100% of MeCN in H
in 30 min, 100% of MeCN for 15 min; B: linear gradient 0 to 50% of MeCN in H O in 5 min,
linear gradient to 95% of MeCN in H O in 5 min, linear gradient to 100% of MeCN in 5 min,
00% of MeCN for 15 min. High performance flash chromatography (HPFC) were performed
2
O
2
2
1
with ISCO Combiflash Rf system on RediSep Rf Gold Silica Gel Disposable columns or
Reverse Phase (C18) RediSep Rf column. Purity of all final compounds (>95%) was determined
by analytical HPLC or by elemental analysis and clean NMR spectra.
4
-(Thiophen-2-yl)-7-(2’,3’-O-isopropylidene-β-D-ribofuranosyl)-7H-pyrrolo[2,3-
d]pyrimidine (4)
Compound 2a (450 mg, 0.923 mmol) was treated with TBAF (1.5 mL, 1 M solution in THF) at
2
2 °C for 20 min. The mixture was then diluted with EtOAc, washed with H O and the organic
2
phase was dried over MgSO
4
, filtered and concentrated in vacuo. Flash chromatography (SiO ,
2
1
hexane/EtOAc 3:1) gave 4 (290 mg, 84%) as a pale yellow gum. H NMR (500 MHz, DMSO-
d
6
): δ = 1.33 and 1.56 (2 × s, 2 × 3H, (CH
.9 Hz, H-5´a); 3.59 (bdt, 1H, Jgem = 11.9 Hz, J5´b,OH = J5´b,4´ = 5.0 Hz, H-5´b); 4.19 (td, 1H,
4´,5´a = J4´,5´b = 4.8 Hz, J4´,3´ = 3.0 Hz, H-4´); 4.96 (dd, 1H, J3´,2´ = 6.3 Hz, J3´,4´ = 2.9 Hz, H-3´);
3
)
2
C); 3.55 (bdt, 1H, Jgem = 11.9 Hz, J5´a,OH = J5´a,4´ =
4
J
5
.12 (t, 1H, JOH,5´a = JOH,5´b = 5.3 Hz, OH-5´); 5.24 (dd, 1H, J2´,3´ = 6.3 Hz, J2´,1´ = 3.4 Hz, H-
´); 6.39 (d, 1H, J1´,2´ = 3.4 Hz, H-1´); 7.21 (d, 1H, J5,6 = 3.9 Hz, H-5); 7.31 (dd, 1H, J4,5 = 5.1
2
Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.87 (dd, 1H, J5,4 = 5.1 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 7.97 (d,
1
2
H, J6,5 = 3.9 Hz, H-6); 8.19 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-thienyl); 8.77 (s, 1H, H-
1
3
). C NMR (125.7 MHz, DMSO-d
6
): δ = 25.46 and 27.37 ((CH
3
)
2
C); 61.77 (CH -5´); 81.34
2
(
CH-3´); 83.82 (CH-2´); 85.84 (CH-4´); 89.11 (CH-1´); 101.31 (CH-5); 113.06 (C-4a); 113.46
(CH C); 128.75 (CH-6); 129.32 (CH-4-thienyl); 129.92 (CH-3-thienyl); 131.08 (CH-5-
(
)
3 2
thienyl); 142.48 (C-2-thienyl); 150.44 (C-4); 151.14 (CH-2); 151.74 (C-7a). MS (ESI) m/z (%):
+
+
+
3
3
5
96 (100) [M + Na] , 374 (15) [M + H] . HR MS (ESI) for C18
74.11690, found: 374.11700.
H
20
O
4
N S [M + H] calcd:
3
-Fluoro-4-(thiophen-2-yl)-7-(2’,3’-O-isopropylidene-β-D-ribofuranosyl)-7H-pyrrolo[2,3-
d]pyrimidine (5)
A solution of compound 3 (228 mg, 0.685 mmol) in acetone (10 mL) at 22 °C was treated with
2
,2’-dimethoxypropane (0.16 mL, 1.37 mmol) and PTSA.H O (catalytic amount, 20 mg). The
2
1
2
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
mixture was then stirred at 22 °C for 1 h and volatiles were removed in vacuo. Flash
1
chromatography (SiO
2
, hexane/EtOAc 1:1) gave 5 as a yellow oil (214 mg, 84%). H NMR
(
500 MHz, DMSO-d ): δ = 1.33 and 1.56 (2 × s, 2 × 3H, (CH
6
3
2
) C); 3.54–3.62 (m, 2H, H-5´);
4
2
.20 (td, 1H, J4´,5´a = J4´,5´b = 4.6 Hz, J4´,3´ = 2.9 Hz, H-4´); 4.93 (dd, 1H, J3´,2´ = 6.3 Hz, J3´,4´
=
.9 Hz, H-3´); 5.16 (dd, 1H, J2´,3´ = 6.3 Hz, J2´,1´ = 3.3 Hz, H-2´); 5.18 (m, 1H, OH-5´); 6.44
(dd, 1H, J1´,2´ = 3.3 Hz, J1´,F = 1.6 Hz, H-1´); 7.32 (dd, 1H, J4,5 = 5.0 Hz, J4,3 = 3.8 Hz, H-4-
thienyl); 7.91 (dd, 1H, J5,4 = 5.0 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.01 (d, 1H, J6,F = 1.9 Hz, H-
1
3
6
); 8.07 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-thienyl); 8.79 (s, 1H, H-2). C NMR (125.7
MHz, DMSO-d ): 25.43 and 27.34 ((CH C); 61.73 (CH -5´); 81.22 (CH-3´); 83.92 (CH-2´);
5.99 (CH-4´); 88.78 (CH-1´); 102.49 (d, JC,F = 15.4 Hz, C-4a); 111.09 (d, JC,F = 31.5 Hz, CH-
); 113.41 ((CH C); 129.40 (d, JC,F = 2.6 Hz, CH-4-thienyl); 130.40 (d, JC,F = 16.3 Hz, CH-
-thienyl); 132.11 (CH-5-thienyl); 141.59 (d, JC,F = 246.6 Hz, C-5); 141.88 (d, JC,F = 1.5 Hz,
6
3
)
2
2
8
6
3
3 2
)
1
9
C-2-thienyl); 147.29 (d, JC,F = 3.3 Hz, C-7a); 150.39 (d, JC,F = 3.8 Hz, C-4); 151.84 (CH-2). F
NMR (470.3 MHz, DMSO-d
HR MS (ESI) for C18
6
): –156.67 (s, 1F, F-5). MS (ESI) m/z (%): 414 (100) [M + Na]+.
+
H
18
O
4
N
3
FNaS [M + Na] calcd: 414.08943, found: 414.08937.
Diisopropyl ({[5-(2’,3’-O-isopropylidene-[4-(thiophen-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-
-yl]-β-D-ribofuranosyl]oxy}methyl)phosphonate (7)
7
A solution of compound 4 (282 mg, 0.755 mmol) in dry DMF (10 mL) at –20 °C was treated
with tosylate 6 (450 mg, 1.28 mmol) and sodium hydride (60% in mineral oil, 180 mg,
4
.53 mmol). The mixture was then let to warm to 22 °C for 1 h and volatiles were removed in
vacuo by co-distillation with toluene. Flash chromatography (hexane/EtOAc 1:3) gave 7 as a
1
pale yellow oil (166 mg, 40%). H NMR (500 MHz, DMSO-d
6
): δ = 1.19, 1.21 and 1.23 (4 ×
-iPr); 1.33 and 1.57 (2 × s, 2 × 3H, (CH C); 3.68 (dd, 1H,
gem = 10.7 Hz, J5´a,4´ = 5.4 Hz, H-5´a); 3.76 (dd, 1H, Jgem = 10.7 Hz, J5´b,4´ = 4.4 Hz, H-5´b);
.78 (dd, 1H, Jgem = 13.9 Hz, JCH2,P = 8.1 Hz, OCH P); 3.81 (dd, 1H, Jgem = 13.9 Hz, JCH2,P
.1 Hz, OCH P); 4.31 (bddd, 1H, J4´,5´a = 5.4 Hz, J4´, 5´b = 4.4 Hz, J4´,3´ = 3.0 Hz, H-4´); 4.52–
.64 (m, 2H, CH-iPr); 4.97 (dd, 1H, J3´,2´ = 6.2 Hz, J3´,4´ = 3.0 Hz, H-3´); 5.25 (dd, 1H, J2´,3´
d, 4 × 3H, JCH3,CH = 6.2 Hz, CH
3
)
3 2
J
3
8
4
6
5
2
=
2
=
.2 Hz, J2´,1´ = 3.3 Hz, H-2´); 6.41 (d, 1H, J1´,2´ = 3.3 Hz, H-1´); 7.19 (d, 1H, J5,6 = 3.9 Hz, H-
); 7.31 (dd, 1H, J4,5 = 5.0 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.87 (dd, 1H, J5,4 = 5.0 Hz, J5,3 = 1.1
Hz, H-5-thienyl); 7.93 (d, 1H, J6,5 = 3.9 Hz, H-6); 8.19 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-
1
3
3
-thienyl); 8.78 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
CH -iPr); 24.02 (d, JC,P = 3.8 Hz, CH -iPr); 25.42 and 27.34 ((CH
Hz, OCH P); 70.42 and 70.43 (2 × d, JC,P = 6.4 Hz, CH-iPr); 72.72 (d, JC,P = 11.4 Hz, CH
1.36 (CH-3´); 83.65 and 83.70 (CH-2´,4´); 89.01 (CH-1´); 101.47 (CH-5); 113.03 (C-4a);
6
): δ = 23.90 (d, JC,P = 4.6 Hz,
C); 65.36 (d, JC,P = 164.1
-5´);
3
3
)
3 2
2
2
8
1
3
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
1
5
13.66 ((CH
3
) C); 128.69 (CH-6); 129.34 (CH-4-thienyl); 129.95 (CH-3-thienyl); 131.11 (CH-
2
3
1
-thienyl); 142.44 (C-2-thienyl); 150.48 (C-4); 151.22 (CH-2); 151.79 (C-7a). P NMR (202.4
+
MHz, DMSO-d
6
): δ = 20.44 (s, 1P). MS (ESI) m/z (%): 574 (100) [M + Na] , 552 (25) [M +
+
+
H] . HR MS (ESI) for C25
H
35
O
7
N
3
PS [M + H] calcd: 552.19278, found: 552.19291.
Diisopropyl
((5-(2’,3’-O-isopropylidene-(5-fluoro-4-(thiophen-2-yl)-7H-pyrrolo[2,3-
d]pyrimidin-7-yl)-β-D-ribofuranosyl)oxy)methyl)phosphonate (8)
A solution of compound 5 (214 mg, 0.547 mmol) in dry DMF (10 mL) at –20 °C was treated
with tosylate 6 (230 mg, 0.656 mmol) and sodium hydride (60% in mineral oil, 200 mg, 4.92
mmol). The mixture was then let to warm to 22 °C for 5 h and volatiles were removed in vacuo
by co-distillation with toluene. Flash chromatography (SiO
2
, hexane/EtOAc, 1:3) gave 8 as a
): δ = 1.21, 1.22 and 1.23 (4 × d, 4 ×
-iPr); 1.32 and 1.56 (2 × s, 2 × 3H, (CH C); 3.68 (dd, 1H, Jgem
0.7 Hz, J5´a,4´ = 5.0 Hz, H-5´a); 3.71 (dd, 1H, Jgem = 10.7 Hz, J5´b,4´ = 4.0 Hz, H-5´b); 3.82 (d,
H, JCH2,P = 8.2 Hz, OCH P); 4.33 (bddd, 1H, J4´,5´a = 4.9 Hz, J4´, 5´b = 4.0 Hz, J4´,3´ = 2.8 Hz,
1
yellow oil (79 mg, 25%). H NMR (500 MHz, DMSO-d
6
3
1
2
H, JCH3,CH = 6.2 Hz, CH
3
3
)
2
=
2
H-4´); 4.54–4.65 (m, 2H, CH-iPr); 4.94 (dd, 1H, J3´,2´ = 6.1 Hz, J3´,4´ = 2.8 Hz, H-3´); 5.15 (dd,
H, J2´,3´ = 6.1 Hz, J2´,1´ = 3.3 Hz, H-2´); 6.46 (dd, 1H, J1´,2´ = 3.3 Hz, J1´,F = 1.6 Hz, H-1´); 7.32
dd, 1H, J4,5 = 5.0 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.91 (dd, 1H, J5,4 = 5.0 Hz, J5,3 = 1.1 Hz, H-
-thienyl); 7.93 (d, 1H, J6,F = 1.9 Hz, H-6); 8.07 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-
1
(
5
1
3
thienyl); 8.80 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
4.5 Hz, CH -iPr); 23.98 (2 × d, JC,P = 3.8 Hz, CH -iPr); 25.40 and 27.33 ((CH
C,P = 164.2 Hz, OCH P); 70.42 and 70.44 (2 × d, JC,P = 6.4 Hz, CH-iPr); 72.73 (d, JC,P = 11.7
-5´); 81.25 (CH-3´); 83.74 and 83.75 (CH-2´,4´); 88.72 (CH-1´); 102.52 (d, JC,F = 15.4
C); 129.44 (d, JC,F = 2.6 Hz, CH-
-thienyl); 130.42 (d, JC,F = 16.2 Hz, CH-3-thienyl); 132.15 (CH-5-thienyl); 141.78 (d, JC,F
47.1 Hz, C-5); 141.85 (d, JC,F = 1.6 Hz, C-2-thienyl); 147.37 (d, JC,F = 3.4 Hz, C-7a); 150.44
6
): δ = 23.85 and 23.87 (2 × d, JC,P
=
3
3
)
3 2
C); 65.38 (d,
J
2
Hz, CH
2
Hz, C-4a); 110.94 (d, JC,F = 31.1 Hz, CH-6); 113.59 ((CH
3 2
)
4
2
=
1
9
(
d, JC,F = 3.8 Hz, C-4); 151.92 (CH-2). F NMR (470.3 MHz, DMSO-d ): δ = –156.16 (s, 1F,
6
3
1
F-5). P NMR (202.4 MHz, DMSO-d
6
): δ = 20.52 (s, 1P). MS (ESI) m/z (%): 592 (100) [M +
+
+
+
Na] , 570 (20) [M + H] . HR MS (ESI) for C25
found: 592.16519.
H
33
O
7
N
3
FNaPS [M + Na] calcd: 592.16531,
([5-{(4-[Thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-β-D-
ribofuranosyl}oxy]methyl)phosphonic acid (9)
A solution of compound 7 (160 mg, 0.29 mmol) in dry acetonitrile (10 mL) at 22 °C was treated
with 2,6-lutidin (0.34 mL, 2.90 mmol) and trimethylsilyl bromide (0.19 mL, 1.45 mmol)
dropwise. After 3 days, MeOH/H O 8:2 mixture (1 mL) was added and the mixture was stirred
2
1
4
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
for additional 30 min and volatiles were removed in vacuo and the residue was purified by RP-
HPFC (C-18, H O/MeOH 0 → 100%). The obtained oil was then treated with TFA (1 mL) at
2 °C for 30 min. The mixture was diluted with toluene, volatiles removed in vacuo and the
2
2
residue was purified by RP-HPFC (C-18, H
tBuOH/H
2
O/MeOH 0 → 100%) and lyophilized
0
(
2
O) to afford 9 (69 mg, 56%) as a pale yellow powder. m.p. 128–130 °C. [α] 2
D
–
1
6
5.9 (c 0.141, DMSO). H NMR (500 MHz, DMSO-d
6
): δ = 3.62 (dd, 1H, Jgem = 13.2 Hz, JCH2,P
=
8.9 Hz, OCH
2
P); 3.64 (dd, 1H, Jgem = 13.2 Hz, JCH2,P = 8.9 Hz, OCH P); 3.69 (dd, 1H, Jgem =
2
1
1
4
1
7
0.7 Hz, J5´a,4´ = 4.1 Hz, H-5´a); 3.73 (dd, 1H, Jgem = 10.7 Hz, J5´b,4´ = 3.4 Hz, H-5´b); 4.04 (bq,
H, J4´,5´a = J4´,5´b = J4´,3´ = 3.6 Hz, H-4´); 4.14 (dd, 1H, J3´,2´ = 5.1 Hz, J3´,4´ = 3.3 Hz, H-3´);
.48 (dd, 1H, J2´,1´ = 6.2 Hz, J2´,3´ = 5.1 Hz, H-2´); 6.29 (d, 1H, J1´,2´ = 6.2 Hz, H-1´); 7.13 (dd,
H, J5,6 = 3.9 Hz, J5,LR = 0.5 Hz, H-5); 7.31 (dd, 1H, J4,5 = 5.1 Hz, J4,3 = 3.8 Hz, H-4-thienyl);
.86 (dd, 1H, J5,4 = 5.1 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.02 (d, 1H, J6,5 = 3.9 Hz, H-6); 8.15
1
3
(
dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-thienyl); 8.75 (s, 1H, H-2). C NMR (125.7 MHz,
DMSO-d ): δ = 67.37 (d, JC,P = 160.7 Hz, OCH P); 71.11 (CH-3´); 73.09 (d, JC,P = 12.1 Hz,
CH -5´); 74.11 (CH-2´); 83.46 (CH-4´); 86.60 (CH-1´); 101.18 (CH-5); 113.04 (C-4a); 128.52
CH-6); 129.29 (CH-4-thienyl); 129.69 (CH-3-thienyl); 130.88 (CH-5-thienyl); 142.61 (C-2-
6
2
2
(
3
1
thienyl); 150.17 (C-4); 151.02 (CH-2); 152.45 (C-7a). P NMR (202.4 MHz, DMSO-d
6
): δ =
1
1
1.
7.60 (s, 1P). IR (ATR): ṽ = 3209, 3102, 3010, 2843, 2760, 2320, 1603, 1567, 1513, 1450,
440, 1415, 1384, 1352, 1244, 1127, 1091, 1076, 1062, 940, 916, 863, 730, 603, 555, 464 cm–
–
–
MS (ESI) m/z (%): 426 (100) [M – H] . HR MS (ESI) for C16
H
17
O
7
N
3
PS [M – H] calcd:
.
.
4
4
26.05303, found: 426.05270. Anal. calcd for C16
H
18
N
3
O
7
PS 0.05 CF
3
COOH 1.6 H
2
O: C
1.87, H 4.64, F 0.62, N 9.10, P 6.71 found: C 41.70, H 4.27, F 0.50, N 8.95, P 6.79.
[5-{(5-Fluoro-4-[thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-β-D-
ribofuranosyl}oxy]methyl)phosphonic acid (10)
(
A solution of compound 8 (53 mg, 0.093 mmol) in dry acetonitrile (5 mL) at 22 °C was treated
with 2,6-lutidin (0.11 mL, 0.93 mmol) and trimethylsilyl bromide (0.06 mL, 0.47 mmol)
dropwise. After 24 hours, MeOH/H
stirred for additional 30 min. Volatiles were removed in vacuo and the residue purified by RP-
HPFC (C-18, H O/MeOH 0 → 100%). The obtained oil was then treated with TFA (1 mL) at
2 °C for 30 min. The mixture was diluted with toluene, volatiles removed in vacuo, and the
residue purified by RP-HPFC (C-18, H O/MeOH 0 → 100%) and lyophilized (tBuOH/H O) to
give phosphonic acid 10 (30 mg, 73%) as a yellow powder. m.p. 183–188 °C. [α] 20
–45.8 (c
): δ = 3.64 (d, 2H, JCH2,P = 9.0 Hz, OCH P);
.67 (dd, 1H, Jgem = 10.7 Hz, J5´a,4´ = 4.0 Hz, H-5´a); 3.71 (dd, 1H, Jgem = 10.7 Hz, J5´b,4´ = 3.3
2
O 8:2 mixture (1 mL) was added and the mixture was
2
2
2
2
D
1
0
3
.179, DMSO). H NMR (500 MHz, DMSO-d
6
2
1
5
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
Hz, H-5´b); 4.04 (m, 1H, H-4´); 4.11 (dd, 1H, J3´,2´ = 5.0 Hz, J3´,4´ = 2.9 Hz, H-3´); 4.42 (dd,
H, J2´,1´ = 6.4 Hz, J2´,3´ = 5.0 Hz, H-2´); 6.35 (dd, 1H, J1´,2´ = 6.4 Hz, J1´,F = 2.1 Hz, H-1´); 7.32
dd, 1H, J4,5 = 5.0 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.90 (dd, 1H, J5,4 = 5.0 Hz, J5,3 = 1.1 Hz, H-
-thienyl); 8.02 (d, 1H, J6,F = 1.8 Hz, H-6); 8.07 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-
1
(
5
1
3
thienyl); 8.77 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
OCH P); 71.20 (CH-3´); 73.11 (d, JC,P = 12.8 Hz, CH -5´); 74.12 (CH-2´); 83.71 (CH-4´); 86.20
CH-1´); 102.44 (d, JC,F = 15.3 Hz, C-4a); 110.85 (d, JC,F = 31.0 Hz, CH-6); 129.38 (d, JC,F
6
): δ = 67.30 (d, JC,P = 160.7 Hz,
2
2
(
=
2
.6 Hz, CH-4-thienyl); 130.29 (d, JC,F = 16.2 Hz, CH-3-thienyl); 131.94 (CH-5-thienyl); 141.70
(d, JC,F = 246.6 Hz, C-5); 142.02 (d, JC,F = 1.6 Hz, C-2-thienyl); 149.01 (d, JC,F = 3.3 Hz, C-
1
9
7
1
3
1
a); 150.19 (d, JC,F = 3.8 Hz, C-4); 151.71 (CH-2). F NMR (470.3 MHz, DMSO-d
6
): δ = –
): δ = 17.66 (s, 1P). IR (ATR): ṽ = 3401,
265, 3107, 2936, 2900, 2841, 2760, 2750, 1593, 1562, 1530, 1458, 1447, 1427, 1385, 1354,
3
1
56.38 (s, 1F, F-5). P NMR (202.4 MHz, DMSO-d
6
-1
247, 1196, 1132, 1104, 1079, 1062, 1048, 942, 859, 720, 602, 561, 467 cm . MS (ESI) m/z
–
–
(
%): 444 (100) [M – H] . HR MS (ESI) for C16
H O
16 7
N
3
FPS [M – H] calcd: 444.04361, found:
.
.
4
44.04327. Anal. calcd for C16
H17FN
3
O
7
PS 0.3 CF
3
COOH 0.8 H
2
O: C 40.36, H 3.86, F 7.31,
N 8.51, P 6.27 found: C 40.68, H 4.06, F 6.95, N 8.16, P 5.93.
Diethyl ([2-{4-chloro-7H-pyrrolo[2,3-d]pyrimidin-7-yl}ethoxy]methyl)phosphonate (13)
A solution of compound 11 (307 mg, 2 mmol) in dry DMF (20 mL) at 22 °C was treated with
sodium hydride (60% in mineral oil, 96 mg, 2.4 mmol). After 30 min, diethyl [(2-
chloroethoxy)methyl]phosphonate (692 mg, 3 mmol) was added dropwise and the mixture was
heated to 80 °C for 2 h. After cooling, volatiles were removed in vacuo by co-distillation with
toluene. Flash chromatography (SiO
2
, CHCl /MeOH, 25:1) gave 13 in mixture with starting
3
diethyl [(2-chloroethoxy)methyl]phosphonate as a yellow oil (837 mg) used without further
1
purification for following step. H NMR (500 MHz, DMSO-d
6
): δ = 1.10 (t, 6H, JCH3,CH2 = 7.1
Hz, CH
CH CH
d, 1H, J6,5 = 3.6 Hz, H-6); 8.63 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
3
CH
2
O); 3.82 (d, 2H, JCH2,P = 8.4 Hz, OCH
CH O); 6.66 (d, 1H, J5,6 = 3.6 Hz, H-5); 7.76
): δ = 16.34 (d,
CH O); 63.96 (d,
O); 98.48 (CH-5); 116.93 (C-4a);
2
P); 3.83–3.92 (m, 6H, NCH
2
CH O,
2
3
2
O); 4.47 (bt, 2H, JCH2,CH2 = 5.2 Hz, NCH
2
2
1
3
(
6
J
C,P = 5.6 Hz, CH
C,P = 162.4 Hz, OCH
31.94 (CH-6); 150.39 (CH-2); 150.74 (C-4); 150.93 (C-7a). P NMR (202.4 MHz, DMSO-
3
CH
2
O); 44.13 (NCH
2
CH
2
O); 61.87 (d, JC,P = 6.3 Hz, CH
3
2
J
2
P); 70.87 (d, JC,P = 11.8 Hz, NCH
2
CH
2
3
1
1
d
+
+
6
): δ = 21.93 (s, 1P). MS (ESI) m/z (%): 370 (100) [M + Na] , 348 (50) [M + H] . HR MS
+
(
ESI) for C13
Diisopropyl
phosphonate (14)
H
20
O
4
N
3
ClP [M + H] calcd: 348.08745, found: 348.08754.
([2-{4-chloro-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-7-yl}ethoxy]methyl)
1
6
This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201900509
A solution of compound 12 (343 mg, 2 mmol) in dry DMF (20 mL) at 22 °C was treated with
sodium hydride (60% in mineral oil, 96 mg, 2.4 mmol). After 30 min, diisopropyl [(2-
chloroethoxy)methyl]phosphonate (621 mg, 2.4 mmol) was added dropwise and the mixture
was heated to 80 °C for 3 h. After cooling, volatiles were removed in vacuo by co-distillation
with toluene. Flash chromatography (SiO
2
, CHCl /MeOH, 25:1) gave phosphonate 14 in
3
mixture with starting diisopropyl [(2-chloroethoxy)methyl]phosphonate as an orange oil
1
(
631 mg) used without further purification for the following step. H NMR (500 MHz, DMSO-
d
6
): δ = 1.07 and 1.13 (2 × d, 2 × 6H, JCH3,CH = 6.2 Hz, CH
bt, 2H, JCH2,CH2 = 5.1 Hz, NCH CH O); 4.38–4.47 (m, 4H, NCH
6,F = 2.2 Hz, H-6); 8.66 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
.5 Hz, CH -iPr); 23.87 (d, JC,P = 3.9 Hz, CH -iPr); 43.89 (NCH CH O); 64.65 (d, JC,P = 164.1
Hz, OCH P); 70.29 (d, JC,P = 6.4 Hz, CH-iPr); 70.65 (d, JC,P = 11.9 Hz, NCH
3
-iPr); 3.76 (m, 2H, OCH
CH O, CH-iPr); 7.80 (d, 1H,
): δ = 23.68 (d, JC,P =
2
P); 3.88
(
2
2
2
2
1
3
J
6
4
3
3
2
2
2
2
CH
2
O); 105.76
(d, JC,F = 13.7 Hz, C-4a); 114.74 (d, JC,F = 26.3 Hz, CH-6); 139.47 (d, JC,F = 247.1 Hz, C-5);
1
9
1
46.21 (d, JC,F = 1.4 Hz, C-7a); 148.85 (d, JC,F = 3.8 Hz, C-4); 151.19 (CH-2). F NMR (470.3
3
1
MHz, DMSO-d
6
): δ = –167.77 (s, 1F, F-5). P NMR (202.4 MHz, DMSO-d
6
): δ = 20.01 (s,
+
ClFNaP [M + Na]+
1
P). MS (ESI) m/z (%): 416 (100) [M + Na] . HR MS (ESI) for C15
H
22
O
4
N
3
calcd: 416.09127, found: 416.09115.
Diethyl (2-[2-{4-chloro-7H-pyrrolo[2,3-d]pyrimidin-7-yl}ethoxy]ethyl)phosphonate (15)
A solution of compound 11 (307 mg, 2 mmol) in dry DMF (20 mL) at 22 °C was treated with
sodium hydride (60% in mineral oil, 96 mg, 2.4 mmol). After 30 min, diethyl [2-(2-
chloroethoxy)ethyl]phosphonate (587 mg, 2.4 mmol) was added dropwise and the mixture was
heated to 80 °C for 2 h. After cooling, volatiles were removed in vacuo by co-distillation with
toluene. Flash chromatography (SiO
2
, CHCl /MeOH, 25:1) gave 15 in mixture with starting
3
diethyl [2-(2-chloroethoxy)ethyl]phosphonate as an orange oil (685 mg), which was used
1
without further purification for the following step. H NMR (500 MHz, DMSO-d
6
): δ = 1.16 (t,
6
H, JCH3,CH2 = 7.1 Hz, CH
P); 3.56 (dt, 2H, JCH2,P = 13.3 Hz, JCH2,CH2 = 7.3 Hz, OCH
CH2,CH2 = 5.4 Hz, NCH O); 3.90 (dq, JCH2,P = 8.2 Hz, JCH2,CH3 = 7.1 Hz, CH
bt, 2H, JCH2,CH2 = 5.4 Hz, NCH O); 6.65 (d, 1H, J5,6 = 3.6 Hz, H-5); 7.79 (d, 1H, J6,5 = 3.6
Hz, H-6); 8.63 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d ): δ = 16.40 (d, JC,P = 5.9 Hz,
CH CH O); 26.03 (d, JC,P = 137.0 Hz, OCH CH P); 44.36 (NCH
Hz, CH CH O); 64.49 (d, JC,P = 1.6 Hz, OCH CH P); 68.54 (NCH
3
CH O); 1.97 (dt, 2H, JCH2,P = 18.3 Hz, JCH2,CH2 = 7.3 Hz,
2
OCH
2
CH
2
2
CH
2
P); 3.79 (bt, 2H,
CH O); 4.44
J
2
CH
2
3
2
(
2
CH
2
1
3
6
3
2
2
2
2
CH
2
O); 61.13 (d, JC,P = 6.2
CH O); 98.49 (CH-5);
3
2
2
2
2
2
3
1
1
16.91 (C-4a); 132.01 (CH-6); 150.38 (CH-2); 150.74 (C-4); 150.88 (C-7a). P NMR (202.4
1
7
This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201900509
+
MHz, DMSO-d
6
): δ = 29.50 (s, 1P). MS (ESI) m/z (%): 384 (100) [M + Na] , 362 (20) [M +
+
+
H] . HR MS (ESI) for C14
H
22
O
4
N
3
ClP [M + H] calcd: 362.10310, found: 362.10325.
Diethyl
(2-[2-{4-chloro-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-7-yl}ethoxy]ethyl)
phosphonate (16)
A solution of compound 12 (343 mg, 2 mmol) in dry DMF (20 mL) at 22 °C was treated with
sodium hydride (60% in mineral oil, 96 mg, 2.4 mmol). After 30 min, diethyl [2-(2-
chloroethoxy)ethyl]phosphonate (587 mg, 2.4 mmol) was added dropwise and the mixture was
heated to 80 °C for 3 h. After cooling, volatiles were removed in vacuo by co-distillation with
toluene. Flash chromatography (SiO
2
, CHCl /MeOH, 25:1) gave phosphonate 16 in a mixture
3
with starting diethyl [2-(2-chloroethoxy)ethyl]phosphonate as an orange oil (557 mg), which
1
was used without further purification for the following step. H NMR (500 MHz, DMSO-d
6
):
δ = 1.16 (t, 6H, JCH3,CH2 = 7.1 Hz, CH
OCH CH P); 3.56 (dt, 2H, JCH2,P = 13.8 Hz, JCH2,CH2 = 7.2 Hz, OCH
CH2,CH2 = 5.3 Hz, NCH O); 3.91 (dq, JCH2,P = 8.2 Hz, JCH2,CH3 = 7.0 Hz, CH
t, 2H, JCH2,CH2 = 5.3 Hz, NCH O); 7.84 (d, 1H, J6,F = 2.2 Hz, H-6); 8.65 (s, 1H, H-2). C
): δ = 16.36 (d, JC,P = 5.9 Hz, CH CH O); 26.00 (d, JC,P = 137.3
O); 61.10 (d, JC,P = 6.1 Hz, CH CH O); 64.50 (d, JC,P = 1.8
O); 105.68 (d, JC,F = 13.8 Hz, C-4a); 114.81 (d, JC,F = 26.2
3
CH
2
O); 1.98 (dt, 2H, JCH2,P = 18.2 Hz, JCH2,CH2 = 7.2 Hz,
2
2
2
CH
2
P); 3.77 (t, 2H,
CH O); 4.40
J
2
CH
2
3
2
1
3
(
2
CH
2
NMR (125.7 MHz, DMSO-d
Hz, OCH CH P); 44.04 (NCH
Hz, OCH CH P); 68.39 (NCH
6
3
2
2
2
2
2
CH
2
3
2
2
2
CH
2
Hz, CH-6); 139.49 (d, JC,F = 247.0 Hz, C-5); 146.11 (d, JC,F = 1.4 Hz, C-7a); 148.84 (d, JC,F
=
1
9
): δ = –167.61 (s, 1F, F-5). 31P
3
.7 Hz, C-4); 151.15 (CH-2). F NMR (470.3 MHz, DMSO-d
6
NMR (202.4 MHz, DMSO-d
6
): δ = 28.42 (s, 1P). MS (ESI) m/z (%): 402 (100) [M + Na]+,
+
+
3
3
80 (20) [M + H] . HR MS (ESI) for C14
H
21
O N
4 3
ClFP [M + H] calcd: 380.09368, found:
80.09393.
Diethyl
([2-{4-(thiophen-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-7-yl}ethoxy]methyl)
phosphonate (17)
An argon purged mixture of compound 13 (348 mg, 1 mmol), 2-thienylboronic acid (141 mg,
1
0
.1 mmol), Na
2
CO
3
(318 mg, 3 mmol), Pd(OAc)
2
(6 mg, 0.025 mmol) and TPPTS (36 mg,
.063 mmol) in H
2
O/MeCN 2:1 (10 mL) was stirred at 100 °C for 1 h. After cooling, the mixture
was diluted with MeOH (20 mL) and volatiles were removed in vacuo. Flash chromatography
SiO CHCl /MeOH, 30:1) gave 17 contaminated by diethyl [(2-
(
2
,
3
chloroethoxy)methyl]phosphonate from the previous step as a yellow oil (396 mg), which was
1
used without further purification for the following step. H NMR (500 MHz, DMSO-d
6
): δ =
P); 3.85–3.96 (m,
O); 7.09 (d, 1H, J5,6
1
6
.10 (t, 6H, JCH3,CH2 = 7.1 Hz, CH
3
CH
2
O); 3.84 (d, 2H, JCH2,P = 8.4 Hz, OCH
2
H, NCH
2
CH
2
O, CH
3
CH
2
O); 4.47 (bt, 2H, JCH2,CH2 = 5.2 Hz, NCH
2
CH
2
=
1
8
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
3
.7 Hz, H-5); 7.30 (dd, 1H, J4,5 = 5.1 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.74 (d, 1H, J6,5 = 3.7 Hz,
H-6); 7.84 (dd, 1H, J5,4 = 5.1 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.15 (dd, 1H, J3,4 = 3.8 Hz, J3,5
=
=
=
1
3
1
5
1
.1 Hz, H-3-thienyl); 8.73 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
.7 Hz, CH CH O); 43.57 (NCH CH O); 61.89 (d, JC,P = 6.2 Hz, CH CH
62.5 Hz, OCH P); 71.03 (d, JC,P = 11.9 Hz, NCH CH
6
): δ = 16.36 (d, JC,P
3
2
2
2
3
2
O); 63.99 (d, JC,P
2
2
2
O); 99.51 (CH-5); 112.56 (C-4a); 129.22
(CH-4-thienyl); 129.50 (CH-3-thienyl); 130.67 (CH-5-thienyl); 131.43 (CH-6); 142.83 (C-2-
3
1
thienyl); 149.95 (C-4); 150.69 (CH-2); 151.63 (C-7a). P NMR (202.4 MHz, DMSO-d ): δ =
6
+
+
2
1.98 (s, 1P). MS (ESI) m/z (%): 418 (100) [M + Na] , 396 (40) [M + H] . HR MS (ESI) for
+
C
17
H
22
O
4
N
3
NaPS [M + Na] calcd: 418.09608, found: 418.09599.
Diisopropyl
([2-{5-fluoro-4-(thiophen-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-7-
yl}ethoxy]methyl)phosphonate (18)
An argon purged mixture of compound 14 (631 mg, 1.6 mmol), 2-thienylboronic acid (226 mg,
1
.8 mmol), Na
mmol) in H O/MeCN 2:1 (20 mL) was stirred at 100 °C for 1 h. After cooling, the mixture was
diluted with MeOH (20 mL) and volatiles were removed in vacuo. Flash chromatography (SiO
CHCl /MeOH 50:1) gave 18 contaminated by diisopropyl [(2-chloroethoxy)
2
CO
3
(510 mg, 4.8 mmol), Pd(OAc)
2
(9 mg, 0.04 mmol) and TPPTS (57 mg, 0.1
2
2
,
3
methyl]phosphonate from the previous step as a yellow oil (581 mg), which was used without
1
further purification for the following step. H NMR (500 MHz, DMSO-d
6
): δ = 1.09 and 1.14
P); 3.90 (t, 2H,
O, CH-iPr); 7.30 (dd, 1H, J4,5
.1 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.76 (d, 1H, J6,F = 2.1 Hz, H-6); 7.88 (dd, 1H, J5,4 = 5.1 Hz,
5,3 = 1.1 Hz, H-5-thienyl); 8.05 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-thienyl); 8.74 (s, 1H,
(2 × d, 2 × 6H, JCH3,CH = 6.2 Hz, CH
3
-iPr); 3.78 (d, 2H, JCH2,P = 8.4 Hz, OCH
CH
2
J
CH2,CH2 = 5.1 Hz, NCH CH O); 4.39–4.49 (m, 4H, NCH
2
2
2
2
=
5
J
1
3
H-2). C NMR (125.7 MHz, DMSO-d
.8 Hz, CH -iPr); 43.38 (NCH CH O); 64.68 (d, JC,P = 164.2 Hz, OCH
Hz, CH-iPr); 70.77 (d, JC,P = 11.9 Hz, NCH CH O); 101.64 (d, JC,F = 14.6 Hz, C-4a); 113.92
d, JC,F = 30.7 Hz, CH-6); 129.29 (d, JC,F = 2.6 Hz, CH-4-thienyl); 129.91 (d, JC,F = 16.2 Hz,
6
): δ = 23.70 (d, JC,P = 4.6 Hz, CH
3
-iPr); 23.87 (d, JC,P =
3
3
2
2
2
P); 70.29 (d, JC,P = 6.4
2
2
(
CH-3-thienyl); 131.69 (CH-5-thienyl); 140.46 (d, JC,F = 244.3 Hz, C-5); 142.22 (d, JC,F = 1.7
Hz, C-2-thienyl); 146.76 (d, JC,F = 3.4 Hz, C-7a); 149.91 (d, JC,F = 3.8 Hz, C-4); 151.26 (CH-
1
9
31
2
d
). F NMR (470.3 MHz, DMSO-d
6
): δ = –158.90 (s, 1F, F-5). P NMR (202.4 MHz, DMSO-
+
+
6
): δ = 18.89 (s, 1P). MS (ESI) m/z (%): 464 (100) [M + Na] , 442 (30) [M + H] . HR MS
+
(
ESI) for C19
Diethyl
yl}ethoxy]ethyl)phosphonate (19)
H
25
O
4
N
3
FNaPS [M + Na] calcd: 464.11796, found: 464.11784.
(2-[2-{4-(thiophen-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-7-
1
9
This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201900509
An argon purged mixture of compound 15 (685 mg, 1.89 mmol), 2-thienylboronic acid (267
mg, 2.08 mmol), Na CO (602 mg, 5.67 mmol), Pd(OAc) (10 mg, 0.047 mmol) and TPPTS
67 mg, 0.12 mmol) in H O/MeCN 2:1 (20 mL) was stirred at 100 °C for 1 h. After cooling,
the mixture was diluted with MeOH (20 mL) and volatiles were removed in vacuo. Flash
chromatography (SiO , CHCl /MeOH 25:1) gave 19 contaminated by diethyl [2-(2-
2
3
2
(
2
2
3
chloroethoxy)ethyl]phosphonate from the previous step as a yellow oil (635 mg), which was
1
used without further purification for the following step. H NMR (500 MHz, DMSO-d
6
): δ =
1
.15 (t, 6H, JCH3,CH2 = 7.1 Hz, CH
P); 3.58 (dt, 2H, JCH2,P = 13.2 Hz, JCH2,CH2 = 7.3 Hz, OCH
CH2,CH2 = 5.4 Hz, NCH O); 3.90 (dq, JCH2,P = 8.2 Hz, JCH2,CH3 = 7.1 Hz, CH
t, 2H, JCH2,CH2 = 5.4 Hz, NCH O); 7.08 (d, 1H, J5,6 = 3.7 Hz, H-5); 7.30 (dd, 1H, J4,5 = 5.1
Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.77 (d, 1H, J6,5 = 3.7 Hz, H-6); 7.84 (dd, 1H, J5,4 = 5.1 Hz, J5,3
1.1 Hz, H-5-thienyl); 8.15 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-thienyl); 8.73 (s, 1H, H-
3
CH O); 1.98 (dt, 2H, JCH2,P = 18.3 Hz, JCH2,CH2 = 7.3 Hz,
2
OCH
2
CH
2
2
CH
2
P); 3.81 (bt, 2H,
CH O); 4.44
J
2
CH
2
3
2
(
2
CH
2
=
1
3
2
1
). C NMR (125.7 MHz, DMSO-d
37.0 Hz, OCH CH P); 43.81 (NCH
1.4 Hz, OCH CH P); 68.68 (NCH
6
): δ = 16.39 (d, JC,P = 5.8 Hz, CH
3
CH
O); 61.11 (d, JC,P = 6.2 Hz, CH CH
O); 99.50 (CH-5); 115.53 (C-4a); 129.18 (CH-4-
2
O); 26.06 (d, JC,P
=
2
2
2
CH
2
3
2
O); 64.50 (d, JC,P
=
2
2
2
CH
2
thienyl); 129.48 (CH-3-thienyl); 130.64 (CH-5-thienyl); 131.48 (CH-6); 142.83 (C-2-thienyl);
3
1
1
1
49.93 (C-4); 150.66 (CH-2); 151.09 (C-7a). P NMR (202.4 MHz, DMSO-d ): δ = 29.51 (s,
6
+
+
P). MS (ESI) m/z (%): 432 (100) [M + Na] , 410 (20) [M + H] . HR MS (ESI) for
+
C
18
H
24
O
4
N
3
NaPS [M + Na] calcd: 432.11173, found: 432.11179.
Diethyl
(2-[2-{5-fluoro-4-(thiophen-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-7-
yl}ethoxy]ethyl)phosphonate (20)
An argon purged mixture of compound 16 (557 mg, 1.47 mmol), 2-thienylboronic acid
(206 mg, 1.62 mmol), Na
2
CO
3
(466 mg, 4.41 mmol), Pd(OAc) (8 mg, 0.037 mmol) and TPPTS
2
(52 mg, 0.092 mmol) in H
2
O/MeCN 2:1 (15 mL) was stirred at 100 °C for 1 h. After cooling,
the mixture was diluted with MeOH (15 mL) and volatiles were removed in vacuo. Flash
chromatography (SiO , CHCl /MeOH 25:1) gave 20 contaminated by diethyl [2-(2-
2
3
chloroethoxy)ethyl]phosphonate from the previous step as a yellow oil (467 mg), which was
1
used without further purification for the following step. H NMR (500 MHz, DMSO-d
6
): δ =
1
.16 (t, 2 × 3H, JCH3,CH2 = 7.1 Hz, CH
3
CH
P); 3.79 (t, 2H, JCH2,CH2 = 5.3 Hz, NCH
× 2H, JCH2,P = 8.2 Hz, JCH2,CH3 = 7.1 Hz, CH CH O); 4.41 (t, 2H, JCH2,CH2 = 5.3 Hz,
O); 7.31 (dd, 1H, J4,5 = 5.0 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.82 (d, 1H, J6,F = 2.1 Hz,
H-6); 7.88 (dd, 1H, J5,4 = 5.0 Hz, J5,3 = 1.2 Hz, H-5-thienyl); 8.06 (dd, 1H, J3,4 = 3.8 Hz, J3,5
2
O); 2.00 (dt, 2H, JCH2,P = 18.2 Hz, JCH2,CH2 = 7.2 Hz,
OCH CH P); 3.58 (m, 2H, OCH CH
2
2
2
2
2
CH O); 3.91 (dq,
2
2
3
2
NCH
2
CH
2
=
2
0
This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201900509
1
3
1
.2 Hz, H-3-thienyl); 8.74 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
.9 Hz, CH CH O); 26.03 (d, JC,P = 137.1 Hz, OCH CH P); 43.58 (NCH
6.1 Hz, CH CH O); 64.51 (d, JC,P = 1.9 Hz, OCH CH P); 68.51 (NCH
C,F = 14.6 Hz, C-4a); 114.02 (d, JC,F = 30.7 Hz, CH-6); 129.29 (d, JC,F = 2.6 Hz, CH-4-thienyl);
29.97 (d, JC,F = 16.3 Hz, CH-3-thienyl); 131.71 (CH-5-thienyl); 140.49 (d, JC,F = 244.3 Hz,
6
): δ = 16.37 (d, JC,P
=
5
3
2
2
2
2
CH
2
O); 61.20 (d, JC,P
=
3
2
2
2
2
CH O); 101.63 (d,
2
J
1
C-5); 142.22 (d, JC,F = 1.7 Hz, C-2-thienyl); 146.71 (d, JC,F = 3.4 Hz, C-7a); 149.92 (d, JC,F
=
1
9
): δ = –158.72 (s, 1F, F-5). 31P
3
.7 Hz, C-4); 151.27 (CH-2). F NMR (470.3 MHz, DMSO-d
6
NMR (202.4 MHz, DMSO-d
6
): δ = 28.43 (s, 1P). MS (ESI) m/z (%): 450 (100) [M + Na]+,
+
+
4
4
28 (30) [M + H] . HR MS (ESI) for C18
H
24
O N
4 3
FPS [M + H] calcd: 428.12037, found:
28.12042.
([2-{4-(Thiophen-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-7-yl}ethoxy]methyl)phosphonic acid
(21)
A solution of compound 17 (395 mg, 1 mmol) in dry acetonitrile (10 mL) at 22 °C was treated
with 2,6-lutidin (1.16 mL, 10 mmol) and trimethylsilyl bromide (0.66 mL, 5 mmol) dropwise.
After 3 days, MeOH/H
additional 30 min and volatiles were removed in vacuo. RP-HPFC (C-18, H
00%, repeated twice to fully remove 2,6-lutidin) and lyophilization (tBuOH/H
2
O 8:2 mixture (5 mL) was added and the mixture was stirred for
O/MeOH 0 →
O) gave
2
1
2
phosphonic acid 21 (110 mg, 32% overall yield from compound 11) as a yellow powder. m.p.
1
9
3–95 °C. H NMR (500 MHz, DMSO-d
6
): δ = 3.59 (d, 2H, JCH2,P = 8.6 Hz, OCH
O); 4.46 (t, 2H, JCH2,CH2 = 5.4 Hz, NCH CH O); 7.07 (d, 1H,
5,6 = 3.7 Hz); 7.30 (dd, 1H, J4,5 = 5.1 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.77 (d, 1H, J6,5 = 3.7 Hz,
H-6); 7.84 (dd, 1H, J5,4 = 5.1 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.15 (dd, 1H, J3,4 = 3.8 Hz, J3,5
.1 Hz, H-3-thienyl); 8.73 (s, 1H, H-2). 13C NMR (125.7 MHz, DMSO-d
): δ = 43.54
NCH CH O); 66.62 (d, JC,P = 160.3 Hz, OCH P); 70.83 (d, JC,P = 10.7 Hz, NCH CH O);
9.50 (CH-5); 115.53 (C-4a); 129.20 (CH-4-thienyl); 129.51 (CH-3-thienyl); 130.65 (CH-5-
2
P); 3.90 (t,
2
H, JCH2,CH2 = 5.4 Hz, NCH
2
CH
2
2
2
J
=
1
6
(
2
2
2
2
2
9
3
1
thienyl); 131.61 (CH-6); 142.84 (C-2-thienyl); 149.92 (C-4); 150.67 (CH-2); 151.51 (C-7a). P
NMR (202.4 MHz, DMSO-d ): δ = 16.36 (s, 1P). IR (ATR): ṽ = 3430, 3136, 2650, 2343, 1717,
601, 1562, 1456, 1440, 1385, 1344, 1251, 1236, 1214, 1160, 1140, 1118, 1096, 975, 938, 906,
6
1
8
-1
–
53, 811, 726, 708, 661, 465 cm . MS (ESI) m/z (%): 338 (100) [M – H] . HR MS (ESI) for
–
O
PS .
C
13
H
13
O
4
N
3
PS [M – H] calcd: 338.03699, found: 338.03665. Anal. calcd for C13
H
14
N
3
4
0
.45 H
[2-{5-Fluoro-4-(thiophen-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-7-
yl}ethoxy]methyl)phosphonic acid (22)
2
O: C 44.94, H 4.32, N 12.10, found: C 45.13, H 4.28, N 11.83.
(
2
1
This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201900509
A solution of compound 18 (581 mg, 1.32 mmol) in dry acetonitrile (25 mL) at 22 °C was
treated with 2,6-lutidin (1.53 mL, 13.2 mmol) and trimethylsilyl bromide (0.87 mL, 6.6 mmol)
dropwise. After 3 days, MeOH/H
2
O 8:2 mixture (10 mL) was added and the mixture was stirred
O/MeOH 0 →
00%) followed by an ion exchange resin chromatography (Dowex® 1X2, chloride form) and
for additional 30 min and volatiles were removed in vacuo. RP-HPFC (C-18, H
2
1
lyophilization (H
2
O) gave phosphonic acid 22 (hydrochloride, 76 mg, 16% overall yield from
1
compound 12) as a yellow powder. m.p. 162–165 °C. H NMR (500 MHz, DMSO-d
6
): δ = 3.60
O); 4.43 (t, 2H,
O); 7.31 (dd, 1H, J4,5 = 5.1 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.82
d, 1H, J6,F = 2.1 Hz, H-6); 7.89 (dd, 1H, J5,4 = 5.1 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.07 (dd,
(d, 2H, JCH2,P = 8.7 Hz, OCH
2
P); 3.89 (t, 2H, JCH2,CH2 = 5.3 Hz, NCH
2
CH
2
J
CH2,CH2 = 5.3 Hz, NCH CH
2
2
(
1
3
1
H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-thienyl); 8.75 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-
): 43.31 (NCH CH O); δ = 66.41 (d, JC,P = 160.2 Hz, OCH P); 70.66 (d, JC,P = 10.9 Hz,
CH O); 101.67 (d, JC,F = 14.6 Hz, C-4a); 114.22 (d, JC,F = 30.8 Hz, CH-6); 129.31 (d,
C,F = 2.6 Hz, CH-4-thienyl); 130.09 (d, JC,F = 16.2 Hz, CH-3-thienyl); 131.79 (CH-5-thienyl);
d
6
2
2
2
NCH
2
2
J
1
40.47 (d, JC,F = 244.3 Hz, C-5); 142.08 (d, JC,F = 1.6 Hz, C-2-thienyl); 146.63 (d, JC,F = 3.4
1
9
Hz, C-7a); 149.85 (d, JC,F = 3.9 Hz, C-4); 151.20 (CH-2). F NMR (470.3 MHz, DMSO-d
6
): δ
): δ = 16.51 (s, 1P). IR (ATR): ṽ =
432, 3108, 2718, 2700, 2320, 2245, 2182, 2124, 1534, 1440, 1372, 1344, 1023, 1000, 945,
3
1
=
–158.71 (s, 1F, F-5). P NMR (202.4 MHz, DMSO-d
6
3
9
-1
–
35, 863, 826, 709, 560, 468 cm . MS (ESI) m/z (%): 356 (100) [M – H] . HR MS (ESI) for
–
C
13
H
12
O
4
N
3
FPS [M – H] calcd: 356.02756, found: 356.02704. Anal. calcd for C13
H13FN
3
4
O PS
.
.
2
.15 HCl 2.8 H
2
O: C 32.12, H 4.30, Cl 15.68, F 3.91, N 8.64, P 6.37 found: C 32.36, H 4.06,
Cl 15.42, F 3.55, N 8.40, P 6.11.
(2-[2-{4-(Thiophen-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-7-yl}ethoxy]ethyl)phosphonic acid
(23)
A solution of compound 19 (635 mg, 1.55 mmol) in dry acetonitrile (25 mL) at 22 °C was
treated with 2,6-lutidin (1.81 mL, 15.5 mmol) and trimethylsilyl bromide (1.02 mL, 7.75 mmol)
dropwise. After 3 days, MeOH/H
2
O 8:2 mixture (10 mL) was added, the mixture was stirred
O/MeOH 0 →
00%) followed by an ion exchange resin chromatography (Dowex® 1X2, chloride form) and
for additional 30 min and volatiles were removed in vacuo. RP-HPFC (C-18, H
2
1
lyophilization (H
2
O) gave phosphonic acid 23 (hydrochloride, 335 mg, 47% overall yield from
1
compound 11) as a yellow powder. m.p. 208–212 °C. H NMR (500 MHz, DMSO-d
6
): δ = 1.80
CH O);
O); 7.11 (d, 1H, J5,6 = 3.7 Hz, H-5); 7.33 (dd, 1H, J4,5
5.0 Hz, J4,3 = 3.7 Hz, H-4-thienyl); 7.82 (d, 1H, J6,5 = 3.7 Hz, H-6); 7.93 (dd, 1H, J5,4 = 5.0
(
m, 2H, OCH
2
CH
2
P); 3.58 (m, 2H, OCH
CH
2
CH
2
P); 3.78 (t, 2H, JCH2,CH2 = 5.5 Hz, NCH
2
2
4
.45 (t, 2H, JCH2,CH2 = 5.5 Hz, NCH
2
2
=
2
2
This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201900509
Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.24 (dd, 1H, J3,4 = 3.7 Hz, J3,5 = 1.1 Hz, H-3-thienyl); 8.79 (s,
1
3
1
H, H-2). C NMR (125.7 MHz, DMSO-d
NCH CH O); 65.44 (d, JC,P = 1.2 Hz, OCH
12.55 (C-4a); 129.31 (CH-4-thienyl); 130.41 (CH-3-thienyl); 131.68 (CH-5-thienyl); 132.38
6
): δ = 29.03 (d, JC,P = 133.0 Hz, OCH
2
CH P); 44.03
2
(
2
2
2
CH P); 68.44 (NCH CH O); 100.06 (CH-5);
2
2
2
1
3
1
(
CH-6); 140.93 (C-2-thienyl); 148.84 (C-4); 149.61 (CH-2); 151.49 (C-7a). P NMR (202.4
MHz, DMSO-d ): δ = 21.89 (s, 1P). IR (ATR): ṽ = 3436, 3102, 3076, 3055, 2750, 1604, 1578,
560, 1535, 1517, 1501, 1438, 1114, 999, 929, 860, 828, 734, 709, 564, 467 cm . MS (ESI)
6
-1
1
+
+
N
PS [M + H]+
m/z (%): 376 (20) [M + Na] , 354 (100) [M + H] . HR MS (ESI) for C14
H
17
O
4
3
.
.
calcd: 354.06719, found: 354.06730. Anal. calcd for C14
H
16
N
3
O
4
PS 1.35 HCl 1.35 H
2
O: C
3
9.39, H 4.73, Cl 11.21, N 9.84, P 7.26 found: C 39.05, H 4.63, Cl 11.02, N 9.48, P 7.29.
2-[2-{5-Fluoro-4-(thiophen-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-7-
yl}ethoxy]ethyl)phosphonic acid (24)
(
A solution of compound 20 (467 mg, 1.09 mmol) in dry acetonitrile (20 mL) at 22 °C was
treated with 2,6-lutidin (1.27 mL, 10.9 mmol) and trimethylsilyl bromide (0.72 mL, 5.45 mmol)
dropwise. After 3 days, MeOH/H
2
O 8:2 mixture (10 mL) was added, the mixture was stirred
O/MeOH 0 →
00%) followed by an ion exchange resin chromatography (Dowex® 1X2, chloride form) and
for additional 30 min and volatiles were removed in vacuo. RP-HPFC (C-18, H
2
1
lyophilization (H
2
O) gave phosphonic acid 24 (hydrochloride, 281 mg, 38% overall yield from
1
compound 12) as a brownish oil. H NMR (500 MHz, DMSO-d
6
): δ = 1.81 (m, 2H,
CH O); 4.40 (t,
O); 7.30 (dd, 1H, J4,5 = 5.0 Hz, J4,3 = 3.8 Hz, H-4-thienyl);
.83 (d, 1H, J6,F = 2.1 Hz, H-6); 7.89 (dd, 1H, J5,4 = 5.0 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.07
OCH
2
CH
2
P); 3.58 (m, 2H, OCH
2
CH
2
P); 3.75 (t, 2H, JCH2,CH2 = 5.4 Hz, NCH
2
2
2
7
H, JCH2,CH2 = 5.4 Hz, NCH
2
CH
2
1
3
(
dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-thienyl); 8.74 (s, 1H, H-2). C NMR (125.7 MHz,
DMSO-d
6
): δ = 28.97 (d, JC,P = 133.1 Hz, OCH
2
CH
2
P); 43.68 (NCH
2
CH
2
O); 65.42 (d, JC,P
=
=
0
3
.8 Hz, OCH CH P); 68.33 (NCH CH O); 101.69 (d, JC,F = 14.5 Hz, C-4a); 114.28 (d, JC,F
2
2
2
2
0.6 Hz, CH-6); 129.32 (d, JC,F = 2.6 Hz, CH-4-thienyl); 130.22 (d, JC,F = 15.9 Hz, CH-3-
thienyl); 131.89 (CH-5-thienyl); 140.51 (d, JC,F = 244.5 Hz, C-5); 141.88 (d, JC,F = 1.6 Hz, C-
1
9
2
-thienyl); 146.67 (d, JC,F = 3.3 Hz, C-7a); 149.77 (d, JC,F = 3.9 Hz, C-4); 151.08 (CH-2). F
3
1
NMR (470.3 MHz, DMSO-d
6
): δ = –158.59 (s, 1F, F-5). P NMR (202.4 MHz, DMSO-d ): δ
6
=
22.12 (s, 1P). IR (ATR): ṽ = 3428, 3112, 3079, 3056, 2700, 1604, 1592, 1566, 1530, 1511,
-1
1
489, 1428, 1242, 1113, 1099, 973, 931, 846, 657, 601, 561, 463 cm . MS (ESI) m/z (%): 372
+
+
(
100) [M + H] . HR MS (ESI) for C14
H
16
O N
4 3
FPS [M + H] calcd: 372.05777, found:
.
.
3
3
72.05779. Anal. calcd for C14
H15FN
3
O
4
PS 2.4 HCl 3.05 H
2
O: C 32.73, H 4.61, Cl 16.56, F
.70, N 8.18, P 6.03 found: C 32.94, H 4.25, Cl 16.21, F 3.33, N 7.88, P 6.29.
2
3
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
(
S)-1-(4-chloro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3-(trityloxy)propan-2-ol (26)
A solution of compound 11 (461 mg, 3 mmol) in dry DMF (20 mL) at 22 °C was treated with
oxiran 25 (1.044 g, 3.3 mmol) and Cs CO (49 mg, 0.15 mmol). The mixture was heated to 120
C for 2.5 h. After cooling, volatiles were removed in vacuo by co-distillation with toluene.
2
3
°
1
Flash chromatography (SiO
2
, hexane/EtOAc 5:1) gave 26 as a white foam (918 mg, 65%). H
): δ = 2.81 (dd, 1H, Jgem = 9.4 Hz, J3´a,2´ = 5.8 Hz, H-3´a); 2.95 (dd,
H, Jgem = 9.4 Hz, J3´b,2´ = 5.2 Hz, H-3´b); 4.10 (m, 1H, H-2´); 4.29 (dd, 1H, Jgem = 13.9 Hz,
1´a,2´ = 7.3 Hz, H-1´a); 4.44 (dd, 1H, Jgem = 13.9 Hz, J1´b,2´ = 4.7 Hz, H-1´b); 5.36 (d, 1H, JOH,2´
5.1 Hz, OH-2'); 6.56 (d, J5,6 = 3.6 Hz, H-5); 7.24 (m, 3 × 1H, H-p-Ph); 7.30 (m, 3 × 2H, H-
NMR (500 MHz, DMSO-d
6
1
J
=
1
3
m-Ph); 7.35 (m, 3 × 2H, H-o-Ph); 7.64 (d, 1H, J6,5 = 3.6 Hz, H-6); 8.58 (s, 1H, H-2). C NMR
(
125.7 MHz, DMSO-d
CH-5); 116.85 (C-4a); 127.17 (CH-p-Ph); 128.01 (CH-m-Ph); 128.42 (CH-o-Ph); 132.34 (CH-
); 143.79 (C-i-Ph); 150.24 (CH-2); 150.58 (C-4); 150.96 (C-7a). MS (ESI) m/z (%): 492 (100)
6
): δ = 48.11 (CH
2
-1´); 65.79 (CH
2
-3'); 68.51 (CH-2'); 86.09 (C-4'); 98.17
(
6
+
+
[
M + Na] . HR MS (ESI) for C28
H
24
O
2
N ClNa [M + Na] calcd: 492.14493, found: 492.14494.
3
(S)-1-(4-chloro-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3-(trityloxy)propan-2-ol (27)
A solution of compound 12 (515 mg, 3 mmol) in dry DMF (20 mL) at 22 °C was treated with
oxiran 25 (1.044 g, 3.3 mmol) and Cs CO (49 mg, 0.15 mmol). The mixture was heated to 120
C for 2 h. After cooling, volatiles were removed in vacuo by co-distillation with toluene. Flash
2
3
°
1
chromatography (SiO
2
, hexane/EtOAc 5:1) gave 27 as a white foam (447 mg, 32%). H NMR
): δ = 2.78 (dd, 1H, Jgem = 9.5 Hz, J3´a,2´ = 5.9 Hz, H-3´a); 2.96 (dd, 1H,
gem = 9.5 Hz, J3´b,2´ = 5.2 Hz, H-3´b); 4.10 (m, 1H, H-2´); 4.25 (dd, 1H, Jgem = 13.8 Hz, J1´a,2´
(500 MHz, DMSO-d
6
J
=
7.3 Hz, H-1´a); 4.38 (dd, 1H, Jgem = 13.8 Hz, J1´b,2´ = 4.8 Hz, H-1´b); 5.37 (d, 1H, JOH,2´ = 5.2
Hz, OH-2'); 7.21–7.39 (m, 15H, H-o,m,p-Ph); 7.67 (d, 1H, J6,F = 2.2 Hz, H-6); 8.60 (s, 1H, H-
1
3
2
). C NMR (125.7 MHz, DMSO-d
6
): δ = 47.83 (CH
2
-1´); 65.74 (CH
2
-3'); 68.39 (CH-2'); 86.11
(C-4'); 105.67 (d, JC,F = 13.7 Hz, C-4a); 115.10 (d, JC,F = 26.1 Hz, CH-6); 127.18 (CH-p-Ph);
1
1
28.00 (CH-m-Ph); 128.39 (CH-o-Ph); 139.31 (d, JC,F = 247.1 Hz, C-5); 143.73 (C-i-Ph);
1
9
46.22 (d, JC,F = 17.5 Hz, C-7a); 148.71 (d, JC,F = 3.6 Hz, C-4); 151.04 (CH-2). F NMR (470.3
+
MHz, DMSO-d
6
): δ = –167.94 (s, 1F, F-5). MS (ESI) m/z (%): 510 (100) [M + Na] . HR MS
+
(ESI) for C28
H
24
O
2
N
3
ClF [M + H] calcd: 488.15356, found: 488.15350.
’
’
’
(
S)-1 -(4-[thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3 -(trityloxy)propan-2 -ol (28)
A solution of compound 26 (415 mg, 0.88 mmol) in dry DMF (15 mL) at 22 °C was treated
with 2-thiophenyltributyltin (0.56 mL, 1.76 mmol) and Pd(PPh Cl (62 mg, 0.088 mmol). The
mixture was heated to 100 °C for 1 h. After cooling, volatiles were removed in vacuo by co-
distillation with toluene. Flash chromatography (SiO , hexane/EtOAc 5:1) gave 28 as a beige
3
)
2
2
2
2
4
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
1
foam (386 mg, 84%). H NMR (500 MHz, DMSO-d
6
): δ = 2.86 (dd, 1H, Jgem = 9.5 Hz, J3´a,2´
=
=
5
7
.6 Hz, H-3´a); 2.97 (dd, 1H, Jgem = 9.5 Hz, J3´b,2´ = 5.3 Hz, H-3´b); 4.12 (dpent, 1H, J2´,1´a
.3 Hz, J2´,1´b = J2´,OH = J2´,3´a = J2´,3´b = 5.3 Hz, H-2´); 4.27 (dd, 1H, Jgem = 13.8 Hz, J1´a,2´ = 7.3
Hz, H-1´a); 4.46 (dd, 1H, Jgem = 13.8 Hz, J1´a,2´ = 4.6 Hz, H-1´a); 5.36 (d, 1H, JOH,2´ = 5.6 Hz,
OH-2'); 6.99 (d, J5,6 = 3.7 Hz, H-5); 7.22 (m, 3 × 1H, H-p-Ph); 7.26–7.32 (m, 7H, H-m-Ph, H-
4
-thienyl); 7.37 (m, 3 × 2H, H-o-Ph); 7.61 (d, 1H, J6,5 = 3.6 Hz, H-6); 7.84 (dd, 1H, J5,4 = 5.1
Hz, J5,3 = 1.2 Hz, H-5-thienyl); 8.12 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.2 Hz, H-3-thienyl); 8.69 (s,
1
3
1
2
H, H-2). C NMR (125.7 MHz, DMSO-d
6
): δ = 47.64 (CH
2
-1´); 65.90 (CH -3'); 68.65 (CH-
2
'); 86.08 (C-4'); 99.19 (CH-5); 112.54 (C-4a); 127.15 (CH-p-Ph); 128.00 (CH-m-Ph); 128.44
(
CH-o-Ph); 129.16 (CH-4-thienyl); 129.34 (CH-3-thienyl); 130.54 (CH-5-thienyl); 131.88
CH-6); 142.92 (C-2-thienyl); 143.85 (C-i-Ph); 149.77 (C-4); 150.56 (CH-2); 151.67 (C-7a).
(
+
+
MS (ESI) m/z (%): 540 (100) [M + Na] , 518 (60) [M + H] . HR MS (ESI) for C32
H
28
O
2
3
N S
+
[
M + H] calcd: 518.18967, found: 518.18956.
’
’
(
S)-1 -(5-fluoro-4-[thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3 -(trityloxy)propan-
2’
A solution of compound 27 (447 mg, 0.92 mmol) in dry DMF (15 mL) was treated with 2-
thiophenyl tributyltin (0.58 mL, 1.84 mmol) and Pd(PPh Cl (64 mg, 0.092 mmol) and heated
-ol (29)
3
)
2
2
to 100 °C for 1 h. After cooling, volatiles were removed in vacuo by co-distillation with toluene.
1
Flash chromatography (SiO
NMR (500 MHz, DMSO-d
2
, hexane/EtOAc 5:1) gave 29 (457 mg, 93%) as a beige foam. H
6
): δ = 2.81 (dd, 1H, Jgem = 9.5 Hz, J3´a,2´ = 5.7 Hz, H-3´a); 2.96 (dd,
1
=
=
H, Jgem = 9.5 Hz, J3´b,2´ = 5.2 Hz, H-3´b); 4.11 (dpent, 1H, J2,1´a = 7.3 Hz, J2,1´b = J2,3´a = J2,3´b
J
2,OH = 5.3 Hz, H-2´); 4.25 (dd, 1H, Jgem = 13.8 Hz, J1´a,2´ = 7.3 Hz, H-1´a); 4.41 (dd, 1H, Jgem
13.8 Hz, J1´b,2´ = 4.9 Hz, H-1´b); 5.37 (d, 1H, JOH,2´ = 5.6 Hz, OH-2'); 7.22 (m, 3H, H-p-Ph);
.29 (m, 6H, H-m-Ph); 7.31 (dd, 1H, J4,5 = 5.1 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.35 (m, 6H, H-
o-Ph); 7.63 (d, 1H, J6,F = 2.1 Hz, H-6); 7.88 (dd, 1H, J5,4 = 5.1 Hz, J5,3 = 1.2 Hz, H-5-thienyl);
7
1
3
8
.03 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.2 Hz, H-3-thienyl); 8.69 (s, 1H, H-2). C NMR (125.7 MHz,
DMSO-d ): δ = 47.36 (CH -1´); 65.81 (CH -3'); 68.50 (CH-2'); 86.09 (C-4'); 101.64 (d, JC,F
4.6 Hz, C-4a); 114.33 (d, JC,F = 30.5 Hz, CH-6); 127.15 (CH-p-Ph); 127.99 (CH-m-Ph); 128.42
CH-o-Ph); 129.72 (d, JC,F = 2.2 Hz, CH-4-thienyl); 129.85 (d, JC,F = 16.2 Hz, CH-3-thienyl);
31.61 (CH-5-thienyl); 140.28 (d, JC,F = 244.3 Hz, CH-5); 142.31 (C-2-thienyl); 143.78 (C-i-
6
2
2
=
1
(
1
1
9
Ph); 146.78 (d, JC,F = 3.3 Hz, C-7a); 149.78 (d, JC,F = 3.8 Hz, C-4); 151.16 (CH-2). F NMR
(377.3 MHz, DMSO-d
6
): δ = –162.61 (s, 1F, F-5). MS (ESI) m/z (%): 558 (100) [M + Na]+,
+
+
5
5
36 (15) [M + H] . HR MS (ESI) for C32
H
26
O
2
N
3
FNaS [M + Na] calcd: 558.16220, found:
58.16217.
2
5
This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201900509
’
’
Diisopropyl
(S)-([{1 -(4-[thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3 -
’
(
trityloxy)propan-2 -yl}oxy]methyl)phosphonate (30)
A solution of compound 28 (220 mg, 0.43 mmol) in dry DMF (10 mL) at –20 °C was treated
with tosylate 6 (360 mg, 1.08 mmol) and sodium hydride (60% in mineral oil, 100 mg, 2.58
mmol). The mixture was then let to warm to 22 °C for 1 h and volatiles were removed in vacuo
by co-distillation with toluene. Flash chromatography (hexane/EtOAc 1:1) gave 30 as a white
1
foam (125 mg, 42%). H NMR (500 MHz, DMSO-d
6
): δ = 1.10, 1.13, 1.15 and 1.18 (4 × d, 4
-iPr); 2.95 (dd, 1H, Jgem = 10.5 Hz, J3´a,2´ = 5.2 Hz, H-3´a); 3.08
dd, 1H, Jgem = 10.5 Hz, J3´b,2´ = 4.1 Hz, H-3´b); 3.77 (dd, 1H, Jgem = 13.7 Hz, JCH2,P = 9.4 Hz,
OCH P); 3.81 (dd, 1H, Jgem = 13.7 Hz, JCH2,P = 9.3 Hz, OCH P); 4.08 (m, 1H, H-2´); 4.42–4.56
m, 4H, H-1´, CH-iPr); 7.02 (d, 1H, J5,6 = 3.7 Hz, H-5); 7.22 (m, 3H, H-p-Ph); 7.28 (m, 6H, H-
m-Ph); 7.30 (dd, 1H, J4,5 = 5.1 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.34 (m, 6H, H-o-Ph); 7.59 (d,
H, J6,5 = 3.7 Hz, H-6); 7.84 (dd, 1H, J5,4 = 5.1 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.13 (dd, 1H,
×
3H, JCH3,CH = 6.2 Hz, CH
3
(
2
2
(
1
1
3
J
3,4 = 3.8 Hz, J3,5 = 1.2 Hz, H-3-thienyl); 8.67 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
δ = 23.79 and 23.85 (2 × d, JC,P = 4.6 Hz, CH -iPr); 23.92 and 23.96 (2 × d, JC,P = 3.8 Hz, CH
iPr); 44.47 (CH -1´); 63.07 (CH -3'); 64.00 (d, JC,P = 165.3 Hz, OCH P); 70.35 and 70.38 (2 ×
d, JC,P = 6.3 Hz, CH-iPr); 79.31 (d, JC,P = 12.9 Hz, CH-2'); 86.35 (C-4'); 99.63 (CH-5); 112.44
C-4a); 127.73 (CH-p-Ph); 128.04 (CH-m-Ph); 128.39 (CH-o-Ph); 129.19 (CH-4-thienyl);
29.43 (CH-3-thienyl); 130.63 (CH-5-thienyl); 131.42 (CH-6); 142.83 (C-2-thienyl); 143.59
6
):
3
3
-
2
2
2
(
1
3
1
(
C-i-Ph); 149.89 (C-4); 150.65 (CH-2); 151.73 (C-7a). P NMR (202.4 MHz, DMSO-d ): δ =
6
+
1
9.86 (s, 1P). MS (ESI) m/z (%): 718 (100) [M + Na] . HR MS (ESI) for C39
H
42
O
5
N
3
NaPS
+
[
M + Na] calcd: 718.24750, found: 718.24754.
’
’
Diisopropyl
(S)-([{1 -(5-fluoro-4-[thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3 -
’
(
trityloxy)propan-2 -yl}oxy]methyl)phosphonate (31)
A solution of compound 29 (450 mg, 0.84 mmol) in dry DMF (15 mL) at –20 °C was treated
with tosylate 6 (530 mg, 1.43 mmol) and sodium hydride (60% in mineral oil, 200 mg,
5
.04 mmol). The mixture was then let to warm to 22 °C for 1 h. Volatiles were removed in
vacuo by co-distillation with toluene. Flash chromatography (SiO
2
, hexane/EtOAc 1:1) gave 31
): δ = 1.10, 1.13, 1.15 and 1.18
-iPr); 2.95 (dd, 1H, Jgem = 10.5 Hz, J3´a,2´ = 5.1 Hz, H-3´a);
.08 (dd, 1H, Jgem = 10.5 Hz, J3´b,2´ = 4.1 Hz, H-3´b); 3.77 (dd, 1H, Jgem = 13.7 Hz, JCH2,P = 9.5
1
as a beige gum (431 mg, 72%). H NMR (500 MHz, DMSO-d
6
(
4 × d, 4 × 3H, JCH3,CH = 6.2 Hz, CH
3
3
Hz, OCH
2
P); 3.83 (dd, 1H, Jgem = 13.7 Hz, JCH2,P = 9.1 Hz, OCH P); 4.06 (m, 1H, H-2´); 4.41
2
(dd, 1H, Jgem = 14.3 Hz, J1´b,2´ = 4.6 Hz, H-1´b); 4.45–4.56 (m, 3H, H-1´a, CH-iPr); 7.22 (m,
3
H, H-p-Ph); 7.29 (m, 6H, H-m-Ph); 7.31 (dd, 1H, J4,5 = 5.1 Hz, J4,3 = 3.8 Hz, H-4-thienyl);
2
6
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
7
.34 (m, 6H, H-o-Ph); 7.61 (d, 1H, J6,F = 2.1 Hz, H-6); 7.88 (dd, 1H, J5,4 = 5.1 Hz, J5,3 = 1.2
1
3
Hz, H-5-thienyl); 8.03 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.2 Hz, H-3-thienyl); 8.68 (s, 1H, H-2). C
NMR (125.7 MHz, DMSO-d ): δ = 24.02 and 24.10 (2 × d, JC,P = 4.6 Hz, CH -iPr); 24.17 and
4.21 (2 × d, JC,P = 3.8 Hz, CH -iPr); 44.56 (CH -1´); 63.23 (CH -3'); 64.22 (d, JC,P = 165.4
P); 70.62 and 70.65 (2 × d, JC,P = 6.3 Hz, CH-iPr); 79.41 (d, JC,P = 12.8 Hz, CH-2');
6
3
2
3
2
2
Hz, OCH
2
8
6.65 (C-4'); 101.91 (d, JC,F = 14.6 Hz, C-4a); 114.33 (d, JC,F = 30.6 Hz, CH-6); 127.53 (CH-
p-Ph); 128.32 (CH-m-Ph); 128.66 (CH-o-Ph); 129.58 (d, JC,F = 2.3 Hz, CH-4-thienyl); 130.15
d, JC,F = 16.2 Hz, CH-3-thienyl); 131.99 (CH-5-thienyl); 140.72 (d, JC,F = 244.6 Hz, CH-5);
42.51 (d, JC,F = 1.5 Hz, C-2-thienyl); 143.82 (C-i-Ph); 147.16 (d, JC,F = 3.3 Hz, C-7a); 150.15
(
1
1
9
(
d, JC,F = 3.7 Hz, C-4); 151.53 (CH-2). F NMR (377.3 MHz, DMSO-d ): δ = –162.26 (s, 1F,
6
3
1
F-5). P NMR (202.4 MHz, DMSO-d
6
): δ = 19.92 (s, 1P). MS (ESI) m/z (%): 736 (100) [M +
+
+
Na] . HR MS (ESI) for C39
H
41
O
5
N
3
FNaPS [M + Na] calcd: 736.23808, found: 736.23806.
’
’
’
(
S)-([{3 -hydroxy-1 -(4-[thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)propan-2 -
yl}oxy]methyl)phosphonic acid (32)
A solution of compound 30 (161 mg, 0.231 mmol) in dry acetonitrile (10 mL) was treated with
2
,6-lutidin (0.27 mL, 2.31 mmol) and trimethylsilyl bromide (0.15 mL, 1.16 mmol) dropwise.
After 3 days, MeOH/H O 8:2 mixture (1 mL) was added and the mixture was stirred for
additional 30 min. Volatiles were removed in vacuo and the residue purified by RP-HPFC (C-
2
1
1
1
8, H
2
O/MeOH 0 → 100%). The obtained oil was then treated with TFA (1 mL) at 22 °C for
5 min. The mixture was diluted with toluene and volatiles removed in vacuo. RP-HPFC (C-
8, H
2
O/MeOH 0 → 100%) and lyophilization (H
2
O) gave 32 (45 mg, 53%) as a yellow gum.
): δ = 3.38–3.44 (m, 2H, H-3´);
P); 3.62 (dd, 1H, Jgem = 13.4 Hz, JCH2,P
P); 3.79 (m, 1H, H-2´); 4.31 (dd, 1H, Jgem = 14.4 Hz, J1´a,2´ = 6.5 Hz, H-1´a); 4.51
2
0
1
[
α]
D
–7.2 (c 0.319, DMSO). H NMR (500 MHz, DMSO-d
6
3
8
.59 (dd, 1H, Jgem = 13.4 Hz, JCH2,P = 9.0 Hz, OCH
.9 Hz, OCH
2
=
2
(dd, 1H, Jgem = 14.4 Hz, J1´b,2´ = 4.2 Hz, H-1´b); 7.07 (d, 1H, J5,6 = 3.7 Hz, H-5); 7.29 (dd, 1H,
J4,5 = 5.1 Hz, J4,3 = 3.7 Hz, H-4-thienyl); 7.78 (d, 1H, J6,5 = 3.7 Hz, H-6); 7.84 (dd, 1H, J5,4
=
5
.1 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.15 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.2 Hz, H-3-thienyl); 8.73
1
3
(
s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
C,P = 160.7 Hz, OCH
CH-4-thienyl); 129.53 (CH-3-thienyl); 130.66 (CH-5-thienyl); 132.11 (CH-6); 142.85 (C-2-
6
): δ = 44.54 (CH
2
-1´); 60.79 (CH
2
-3'); 65.40 (d,
J
2
P); 81.30 (d, JC,P = 10.2 Hz, CH-2'); 99.54 (CH-5); 112.42 (C-4a); 129.21
(
3
1
thienyl); 149.88 (C-4); 150.66 (CH-2); 151.74 (C-7a). P NMR (202.4 MHz, DMSO-d
6
): δ =
1
1
7.80 (s, 1P). IR (ATR): ṽ = 3237, 3096, 3074, 1516, 1439, 1385, 1213, 1200, 1127, 1110,
-1
094, 1072, 1049, 1027, 995, 972, 940, 858, 825, 554, 466 cm . MS (ESI) m/z (%): 368 (100)
–
–
[
M – H] . HR MS (ESI) for C14
H
15
O
5
N PS [M – H] calcd: 368.04755, found: 368.04681. Anal.
3
2
7
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European Journal of Organic Chemistry
10.1002/ejoc.201900509
.
.
calcd for C14
H
16
N
3
O
5
PS 0.1 CF
3
COOH 2.45 H
2
O: C 40.14, H 4.98, F 1.34, N 9.89, P 7.29
found: C 40.39, H 4.73, F 1.02, N 9.92, P 7.42.
’
’
(
S)-([{1 -(5-fluoro-4-[thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3 -
’
hydroxypropan-2 -yl}oxy]methyl)phosphonic acid (33)
A solution of compound 31 (425 mg, 0.595 mmol) in dry acetonitrile (20 mL) was treated with
2
,6-lutidin (0.69 mL, 5.95 mmol) and trimethylsilyl bromide (0.39 mL, 2.98 mmol) dropwise.
After 3 days, MeOH/H O 8:2 mixture (2 mL) was added and the mixture was stirred for
additional 30 min. Volatiles were removed in vacuo and the residue purified by RP-HPFC (C-
2
1
3
1
8, H
2
O/MeOH 0 → 100%). The obtained oil was then treated with TFA (1 mL) at 22 °C for
0 min. The mixture was diluted with toluene and volatiles removed in vacuo. RP-HPFC (C-
8, H
2
O/MeOH 0 → 100%) and lyophilization (H
2
O) gave 33 (121 mg, 52%) as a yellow gum.
): δ = 3.42 (dd, 1H, Jgem = 11.7
2
0
1
[
α]
D
+9.2 (c 0.076, DMSO). H NMR (500 MHz, DMSO-d
6
Hz, J3´a,2´ = 5.4 Hz, H-3´a); 3.45 (dd, 1H, Jgem = 11.7 Hz, J3´b,2´ = 5.2 Hz, H-3´b); 3.61 (dd, 1H,
gem = 13.4 Hz, JCH2,P = 9.5 Hz, OCH P); 3.67 (dd, 1H, Jgem = 13.4 Hz, JCH2,P = 8.9 Hz, OCH P);
.78 (dtd, 1H, J2´,1´a = 6.8 Hz, J2´,3´a = J2´,3´b = 5.3 Hz, J2´,1´b = 3.9 Hz, H-2´); 4.28 (dd, 1H, Jgem
J
2
2
3
=
14.4 Hz, J1´a,2´ = 6.8 Hz, H-1´a); 4.50 (dd, 1H, Jgem = 14.4 Hz, J1´b,2´ = 3.9 Hz, H-1´b); 7.31
(dd, 1H, J4,5 = 5.0 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.79 (d, 1H, J6,F = 2.0 Hz, H-6); 7.88 (dd,
1
H, J5,4 = 5.0 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.07 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-
1
3
thienyl); 8.74 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
´); 65.61 (d, JC,P = 161.2 Hz, OCH P); 81.20 (d, JC,P = 10.8 Hz, CH-2´); 101.63 (d, JC,F = 14.7
Hz, C-4a); 114.65 (d, JC,F = 30.6 Hz, CH-6); 129.33 (d, JC,F = 2.6 Hz, CH-4-thienyl); 130.03
d, JC,F = 16.3 Hz, CH-3-thienyl); 131.73 (CH-5-thienyl); 140.50 (d, JC,F = 244.4 Hz, C-5);
42.28 (d, JC,F = 1.8 Hz, C-2-thienyl); 146.89 (d, JC,F = 3.4 Hz, C-7a); 149.88 (d, JC,F = 3.9 Hz,
6
): δ = 44.38 (CH
2
-1´); 60.66 (CH
2
-
3
2
(
1
1
9
31
C-4); 151.28 (CH-2). F NMR (470.3 MHz, DMSO-d
202.4 MHz, DMSO-d ): δ = 18.05 (s, 1P). IR (ATR): ṽ = 3432, 3270, 3102, 1602, 1591, 1561,
529, 1444, 1385, 1370, 1112, 1065, 1005, 943, 692, 602, 561 cm . MS (ESI) m/z (%): 386
6
): δ = –158.73 (s, 1F, F-5). P NMR
(
6
-1
1
–
–
(
100) [M – H] . HR MS (ESI) for C14
H
14
O N
5 3
FPS [M – H] calcd: 386.03813, found:
.
.
3
86.03759. Anal. calcd for C14
H15FN
3
O
5
PS 0.1 CF
3
COOH 0.5 H
2
O: C 41.83, H 3.98, F 6.06,
N 10.31, P 7.60 found: C 41.44, H 3.91, F 5.94, N 9.99, P 7.95.
’
’
’
(
S)-1 -(4-[thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)propane-2 ,3 -diol (34)
Compound 28 (193 mg, 0.373 mmol) was treated with TFA (1 mL) at 22 °C for 15 min. The
mixture was diluted with toluene and volatiles removed in vacuo. Flash chromatography (SiO
CHCl –9.9 (c
/MeOH 20:1) gave 34 (63 mg, 61%) as a beige solid. m.p. 149–154 °C. [α] 20
.131, DMSO). H NMR (500 MHz, DMSO-d
2
,
3
D
1
0
6
): δ = 3.33 (dt, 1H, Jgem = 11.1 Hz, J3´a,2´ = J3´a,OH
2
8
This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201900509
=
5.9 Hz, H-3´a); 3.39 (dt, 1H, Jgem = 11.1 Hz, J3´b,2´ = J3´b,OH = 5.4 Hz, H-3´b); 3.89 (dqd, 1H,
2´,1´a = 8.1 Hz, J2´,OH = J2´,3´a = J2´,3´b = 5.6 Hz, J2´,1´b = 3.9 Hz, H-2´); 4.13 (dd, 1H, Jgem = 13.9
Hz, J1´a,2´ = 8.1 Hz, H-1´a); 4.46 (dd, 1H, Jgem = 13.9 Hz, J1´b,2´ = 3.9 Hz, H-1´b); 4.81 (t, 1H,
OH,3´a = JOH,3´b = 5.7 Hz, OH-3´); 5.04 (d, 1H, JOH,2´ = 5.5 Hz, OH-2´); 7.06 (d, 1H, J5,6 = 3.7
Hz, H-5); 7.30 (dd, 1H, J4,5 = 5.1 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.69 (d, 1H, J6,5 = 3.6 Hz, H-
); 7.84 (dd, 1H, J5,4 = 5.1 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.14 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1
J
J
6
1
3
Hz, H-3-thienyl); 8.72 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
3.88 (CH -3'); 70.48 (CH-2'); 99.09 (CH-5); 112.56 (C-4a); 129.17 (CH-4-thienyl); 129.40
CH-3-thienyl); 130.57 (CH-5-thienyl); 132.26 (CH-6); 142.91 (C-2-thienyl); 149.80 (C-4);
6
): δ = 47.64 (CH
2
-1´);
6
2
(
1
1
50.54 (CH-2); 151.67 (C-7a). IR (ATR): ṽ = 3424, 3277, 3111, 3068, 1531, 1519, 1511, 1440,
-1
378, 1118, 1092, 1080, 1075, 1054, 1023, 710, 467 cm . MS (ESI) m/z (%): 298 (100) [M +
+
+
+
Na] , 276 (70) [M + H] . HR MS (ESI) for C13
H O
13 2
N
3
NaS [M + Na] calcd: 298.06207, found:
.
2
5
98.06206. Anal. calcd for C13
H
13
N
3
O
2
S 1.15 CH
3
OH: C 54.44, H 5.68, N 13.46, found: C
4.77, H 5.35, N 13.09.
’
’
’
(
S)-1 -(5-fluoro-4-[thiophen-2-yl]-7H-pyrrolo[2,3-d]pyrimidin-7-yl)propane-2 ,3 -diol (35)
Compound 29 (234 mg, 0.437 mmol) was treated with TFA (1 mL) at 22 °C for 15 min. The
mixture was diluted with toluene and volatiles removed in vacuo. Flash chromatography (SiO
CHCl
/MeOH 20:1) gave 35 (103 mg, 80%) as a pale yellow solid. m.p. 181–183 °C. [α] 20
2
,
3
D
–
1
1
2.3 (c 0.122, DMSO). H NMR (500 MHz, DMSO-d
6
): δ = 3.34 (dt, 1H, Jgem = 11.0 Hz, J3´a,2´
=
J3´a,OH = 6.0 Hz, H-3´a); 3.40 (dt, 1H, Jgem = 11.0 Hz, J3´b,2´ = J3´b,OH = 5.4 Hz, H-3´b); 3.85
(
dqd, 1H, J2´,1´a = 8.3 Hz, J2´,3´a = J2´,3´b = J2´,OH = 5.6 Hz, J2´,1´b = 3.8 Hz, H-2´); 4.09 (dd, 1H,
gem = 13.9 Hz, J1´a,2´ = 8.3 Hz, H-1´a); 4.42 (dd, 1H, Jgem = 13.9 Hz, J1´b,2´ = 3.8 Hz, H-1´b);
J
4
1
.81 (t, 1H, JOH,3´a = JOH,3´b = 5.6 Hz, OH-3´); 5.05 (d, 1H, JOH,2´ = 5.5 Hz, OH-2´); 7.31 (dd,
H, J4,5 = 5.0 Hz, J4,3 = 3.8 Hz, H-4-thienyl); 7.72 (d, 1H, J6,F = 2.1 Hz, H-6); 7.87 (dd, 1H, J5,4
=
5.0 Hz, J5,3 = 1.1 Hz, H-5-thienyl); 8.06 (dd, 1H, J3,4 = 3.8 Hz, J3,5 = 1.1 Hz, H-3-thienyl);
1
3
8
.73 (s, 1H, H-2). C NMR (125.7 MHz, DMSO-d
0.39 (CH-2´); 101.69 (d, JC,F = 14.5 Hz, C-4a); 114.77 (d, JC,F = 30.4 Hz, CH-6); 129.30 (d,
C,F = 2.5 Hz, CH-4-thienyl); 129.92 (d, JC,F = 16.3 Hz, CH-3-thienyl); 131.64 (CH-5-thienyl);
40.23 (d, JC,F = 244.1 Hz, C-5); 142.33 (d, JC,F = 1.6 Hz, C-2-thienyl); 146.77 (d, JC,F = 3.4
6
): δ = 47.51 (CH
2
-1´); 63.84 (CH -3´);
2
7
J
1
1
9
Hz, C-7a); 149.82 (d, JC,F = 3.9 Hz, C-4); 151.16 (CH-2). F NMR (470.3 MHz, DMSO-d
6
): δ
=
–159.25 (s, 1F, F-5). IR (ATR): ṽ = 3427, 3276, 3101, 3070, 3050, 1545, 1529, 1447, 1372,
-1
1
116, 1094, 1085, 1070, 1047, 1008, 693, 563, 467 cm . MS (ESI) m/z (%): 316 (100) [M +
+
+
+
Na] , 294 (15) [M + H] . HR MS (ESI) for C13
H O
13 2
N FS [M + H] calcd: 294.07070, found:
3
2
9
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