Synthesis of novel 17-(5′-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne cycloadditon, and an evaluation of their cytotoxic activity in vitro Dedicated to Professor Irén Vincze on the occasion of her 85th birthday

Article abstract of DOI:10.1016/j.steroids.2015.02.018

The regioselective Cu(I)-catalyzed 1,3-dipolar cycloaddition of 3-methoxyestrane 17α- and 17β-azide epimers (3 and 5) with different terminal alkynes afforded novel 1,4-substituted triazolyl derivatives (8a-f and 11a-f). If the Ph₃P in the clas

Full text of DOI:10.1016/j.steroids.2015.02.018

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Contents lists available at ScienceDirect
Steroids
journal homepage: www.elsevier.com/locate/steroids
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Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via
Cu(I)-catalyzed azide-alkyne cycloaddition, and an evaluation of their
cytotoxic activity in vitro
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Gyula Schneider a, , Tamás Görbe a,1, Erzsébet Mernyák a, János Wölfling a, Tamás Holczbauer b,
⇑
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Mátyás Czugler b, Pál Sohár c, Renáta Minorics d, István Zupkó d,
⇑
a Department of Organic Chemistry, University of Szeged, Dóm tér 8., H-6720 Szeged, Hungary
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b Institute of Organic Chemistry, Research Center of Natural Sciences, Hungarian Academy of Sciences, Pusztaszeri út 59-67., H-1025 Budapest, Hungary
c Institute of Chemistry, Eötvös Lóránd University, Pázmány Péter sétány 1/A., H-1117 Budapest, Hungary
d Department of Pharmacodynamics and Biopharmacy, University of Szeged, Eötvös u.6., H-6720 Szeged, Hungary
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a r t i c l e i n f o
a b s t r a c t
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Article history:
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The regioselective Cu(I)-catalyzed 1,3-dipolar cycloaddition of 3-methoxyestrane 17a- and 17b-azide
Received 19 September 2014
Received in revised form 2 February 2015
Accepted 19 February 2015
Available online xxxx
epimers (3 and 5) with different terminal alkynes afforded novel 1,4-substituted triazolyl derivatives
(8a–c and 10a–c). If the Ph3P in the classical CuAAC process was replaced by Et3N, the formation of small
quantities of 5-iodotriazoles (9a–c and 11a–c) was observed. For the preparation of 5-iodo-1,2,3-triazoles
(9a–c and 11a–c), an improved method was developed, directly from steroidal azides and terminal alky-
nes, in reactions mediated by CuI and ICl as iodinating agents. The antiproliferative activities of the struc-
turally related triazoles were determined in vitro with the microculture tetrazolium assay on six
malignant human cell lines of gynecological origin (HeLa, A2780, MCF7, MB-231, MB-361 and T47D).
X-ray analysis revealed the presence of the iodo substituent on the 1,2,3-triazole ring.
Ó 2015 Published by Elsevier Inc.
Dedicated to Professor emerita Irene Vincze
on the occasion of her 85th birthday.
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Keywords:
1,3-Dipolar cycloaddition
Iodotriazoles
Cytotoxic activity
X-ray analysis
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1. Introduction
the azole appear to constitute a new class of compounds. A number
of diverse triazolyl derivatives have been reported to exhibit biolo-
gical activity, including antibacterial [8], antiallergic [9] and
anti-HIV [10] effects, but steroids containing this kind of structural
moiety have received less attention from both synthetic and phar-
macological aspects [6,11].
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Steroid derivatives in which ring D is modified with exo-hetero-
cycles exhibit numerous forms of biological activity and are attrac-
tive for medicine [1]. Several novel synthesized compounds
containing five- or six-membered 17b-exo-heterocycles are inhibi-
tors of 17
a
-hydroxylase/C17,20-lyase (P45017 ) which can block
The Huisgen 1,3-dipolar cycloaddition of organic azides and
terminal alkynes has been of considerable interest in recent years
following the independent introduction of Cu(I) catalysis in 2002
by the research groups of Sharpless [12] and Meldal [13]. The pres-
ence of the catalyst dramatically improves both the rate and the
regioselectivity of the reaction, leading exclusively to the
1,4-disubstituted 1,2,3-triazole [14].
To the best of our knowledge, relatively few examples are to be
found in the literature in which Cu(I)-catalyzed 1,3-dipolar
azide-alkyne cycloaddition (CuAAC) is applied to steroid azides
[15,16], though it provides convenient facilities for the construc-
tion of triazoles in which the hetero ring is attached to the steroid
nucleus through a nitrogen atom. Banday et al. recently reported
the synthesis of 21-triazolyl derivatives of pregnenolone as poten-
tial anticancer agents through use of the click chemistry approach,
a
androgen synthesis at an early stage, and may therefore be useful
in the treatment of prostate carcinoma [2–5]. A new family of
17-azolyl-
Although a few
D
16-steroids was recently reported by Brodie et al. [6].
D
16-17-azole-androstane steroids are known in
which the azole is attached to the steroid nucleus through a carbon
atom of the heterocycle [7], the isomeric compounds in which the
azole group is attached to the steroid nucleus through a nitrogen of
⇑
Corresponding authors. Fax: +36 (62) 544200 (G. Schneider), +36 (62) 546424
(I. Zupkó).
E-mail addresses: schneider@chem.u-szeged.hu (G. Schneider), zupko@pharm.
u-szeged.hu (I. Zupkó).
1
Present address: Organic Chemistry, Arrhenius Laboratory, Stockholm University,
106 91 Stockholm, Sweden.
http://dx.doi.org/10.1016/j.steroids.2015.02.018
0039-128X/Ó 2015 Published by Elsevier Inc.
Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018

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but without any suggestion concerning their mode of action [17].
The most frequent synthetic modifications are introduced at the
position adjacent to the existing C-2 or C-17 functional groups,
where substitution is facilitated [18,19]. Substitution on C-1 or
C-15 of the sterane skeleton has proved to be more difficult, neces-
sitating several reaction steps, and is therefore rarely performed
[20,21].
during cooling with ice. The reaction mixture was allowed to stand
for 24 h and then poured onto a mixture of ice (500 g) and concen-
trated H2SO4 (50 ml). The crystalline precipitate that separated out
was filtered off, washed thoroughly with water, and recrystallized
from a mixture of acetone and water, resulting in 2b (19.2 g, 87%).
Mp 162–163 °C (Ref. [22]: 162–164 °C).
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The position and the steric orientation of the azido group are
determined by the synthetic method applied. The C-17 azido group
2.3. 3-Methoxyestra-1,3,5(10)-trien-17a-azide (3)
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is generally in the
exchange reaction of 17b-tosylate or mesylate by sodium azide
with Walden inversion.
Frank et al. recently reported the regioselective synthesis of
steroidal 17a-azides with different terminal alkynes by CuAAC,
furnishing novel 1,4-disubstituted triazolyl derivatives in good
yields in both the estrane and the androstane series [19]. The
antiproliferative activities of the structurally related triazoles were
determined in vitro on three malignant human cell lines (HeLa,
MCF7 and A431). Although the antiproliferative activities of the
tested compounds were moderate, the results suggest that steroi-
dal triazoles may induce a disturbance in the cell division by a
mode other than hormone receptor-based action, motivating the
search for further derivatives and optimization for better activities.
a
position, which leads to the nucleophilic
Compound 2b (8.80 g, 20 mmol) was dissolved in
N,N-dimethylformamide (200 ml), and NaN3 (5.2 g, 80 mmol) was
added. The mixture was stirred for 48 h at 100 °C, and then poured
into water (400 ml). The precipitate that formed was filtered off
and washed with water. The residue obtained was dissolved in
CH2Cl2 and chromatographed on silica gel with CH2Cl2/hexane
(1:1, v/v) to yield 3 (5.20 g, 83.6%) as a white solid. Mp 43–45 °C;
91
92
93
94
95
96
Rf = 0.70 (ss B); [a]
20 + 14 (c = 1 in CHCl3). (Found: C, 73.41; H,
97
D
98
7.92. C19H25N3O requires: C, 73.28; H, 8.09%.)
1H NMR 0.79 (s, 3H, 18-H3), 2.86 (m, 2H, 6-H2), 3.59 (d, 1H,
J = 6.5 Hz, 17-H), 3.78 (s, 3H, 3-OCH3), 6.64 (d, 1H, J = 2.2 Hz,
4-H), 6.73 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.22 (d, 1H,
J = 8.6 Hz, 1-H). 13C NMR 17.7 (C-18), 24.3, 26.2, 28.0, 28.7, 29.9,
32.6, 39.1, 43.4, 46.3, 48.6, 55.2 (3-OCH3), 71.6 (C-17), 111.5
(C-2), 113.8 (C-4), 126.3 (C-1), 132.5 (C-10), 137.9 (C-5), 157.5
(C-3).
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112
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We set out to synthesize not only the 17a-azides, but a novel
series of 17b-azide epimers, as starting materials for CuAACs in
order to obtain novel 1,4-disubstituted triazolyl estrone deriva-
tives with different terminal alkynes as reagents. By means of
minor modifications of earlier reported procedures, we found a
new type of compound, the 50-iodotriazolyl derivative. To the best
of our knowledge, no examples are to be found in the literature in
164
2.4. 3-Methoxyestra-1,3,5(10)-trien-17a-iodide (4)
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Compound 2a (17.18 g, 60 mmol), Ph3P (15.78 g, 60.15 mmol)
and imidazole (4.10 g, 60.15 mmol) were dissolved in toluene
(250 ml), and I2 (15.26 g, 60.15 mmol) was added in two portions.
The reaction mixture was stirred at 80 °C for 2 h and allowed to
cool to room temperature. A saturated aqueous Na2SO3 solution
(150 ml) was then added and the resulting mixture was stirred
until all the solids had dissolved. EtOAc (100 ml) was added, and
the organic phase was washed with saturated aqueous NaHCO3
(2 ꢁ 100 ml) and brine (100 ml), dried over Na2SO4 and evaporated
in vacuo. The residue was subjected to column chromatography on
silica gel in CH2Cl2/hexane (1:3, v/v) to yield 4 (19.6 g, 82.4%) as a
which steroidal 50-iodotriazolyl by-products appear during
CuAAC.
We set out to obtain answers to the following questions: (1)
How is the CuAAC process influenced by the steric structure of
the steroidal azides? (2) How can the formation of
50-iodotriazolyl derivatives be influenced? (3) How do the antipro-
liferative activities in the C-17 epimer series differ?
a
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119
2. Experimental
white solid. Mp 95–97 °C; Rf = 0.75 (ss B); [a]
20 –71 (c 1 in CHCl3).
D
(Found: C, 57.42; H, 6.48. C19H25IO requires: C, 57.58; H, 6.36%.)
1H NMR 0.87 (s, 3H, 18-H3), 2.87 (m, 2H, 6-H2), 3.78 (s, 3H,
3-OCH3), 4.43 (d, 1H, J = 6.9 Hz, 17-H), 6.64 (d, 1H, J = 2.2 Hz,
4-H), 6.72 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.21 (d, 1H,
J = 8.6 Hz, 1-H). 13C NMR 15.8 (C-18), 24.6, 27.4, 28.0, 29.9, 36.8,
39.6, 40.8, 43.2, 45.7, 48.2, 48.3, 55.2 (3-OCH3), 111.5 (C-2), 113.8
(C-4), 126.4 (C-1), 132.4 (C-10), 137.9 (C-5), 157.5 (C-3).
2.1. General
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132
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Melting points (mp) were determined on a Kofler block and are
uncorrected. Specific rotations were measured in CHCl3 (c 1) at
20 °C with a POLAMAT-A (Zeiss-Jena) polarimeter and are given
in units of 10ꢀ1 deg cm2 gꢀ1. Elementary analysis data were deter-
mined with a PerkinElmer CHN analyzer model 2400. The reactions
were monitored by TLC on Kieselgel-G (Merck Si 254 F) layers
(0.25 mm thick); solvent systems (ss): (A) CH2Cl2, (B)
CH2Cl2/hexane (1:1, v/v), (C) acetone/toluene/hexane (30:35:35,
v/v). The spots were detected by spraying with 5% phosphomolyb-
dic acid in 50% aqueous phosphoric acid. The Rf values were deter-
mined for the spots observed by illumination at 254 and 365 nm.
Flash chromatography: silica gel 60, 40–63
distilled immediately prior to use. NMR spectra were recorded on
a Bruker DRX 500 instrument at 500 (1H NMR) or 125 MHz (13
NMR). Chemical shifts are reported in ppm (d scale), and coupling
constants (J) in Hz. For the determination of multiplicities, the
J-MOD pulse sequence was used.
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2.5. 3-Methoxyestra-1,3,5(10)-trien-17b-azide (5) and 3-methoxyes
tra-1,3,5(10),16-tetraene (6)
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200
Compound
4
(12.45 g, 30 mmol) was dissolved in
N,N-dimethylformamide (200 ml), and NaN3 (7.46 g, 120 mmol)
was added. The mixture was stirred for 24 h at 60 °C, and then
poured onto ice (600 g). The resulting emulsion was extracted with
CH2Cl2 (3 ꢁ 150 ml). The CH2Cl2 phase was washed with water,
dried over Na2SO4, evaporated in vacuo and subjected to chromato-
graphic separation on silica gel in CH2Cl2/hexane (1:3 v/v) to yield
6 (4.20 g, 49.35%) as a slowly-crystallizing colorless oil. Mp
lm. All solvents were
C
65–67 °C; (Ref. [23]: mp 66–68 °C), Rf=0.80 (ss B); [a]
20 + 109 (c 1
D
in CHCl3). (Found: C, 84.91; H, 9.17. C19H24O requires: C, 85.03;
137
2.2. 3-Methoxyestra-1,3,5(10)-triene-17b-tosylate (2b)
H, 9.01%.) Continued elution resulted in 5 (3.83 g, 41.00%) as a
white solid. Mp 117–119 °C; Rf = 0.65 (ss B); [a]
20 + 42 (c 1 in
D
138
139
140
3-Methoxyestra-1,3,5(10)trien-17b-ol (2a, 14.32 g, 50 mmol)
was dissolved in pyridine (100 ml), and a solution of p-toluenesul-
fonyl chloride (14.25 g, 75 mmol) in pyridine (50 ml) was added
CHCl3). (Found: C, 73.37; H, 8.15. C19H25N3O requires: C, 73.28;
H, 8.09%.) 1H NMR (d, ppm): 0.80 (s, 3H, 18-H3), 2.85 (m, 2H,
6-H2), 3.42 (t, 1H, J = 9.0 Hz, 17-H), 3.78 (s, 3H, 3-OCH3), 6.64
Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018

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(d, 1H, J = 2.2 Hz, 4-H), 6.72 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.20
(d, 1H, J = 8.6 Hz, 1-H). 13C NMR (d, ppm): 12.3 (C-18), 23.3, 26.2,
27.0, 27.4, 29.7, 37.2, 38.8, 43.8, 44.7, 51.2, 55.2 (3-OCH3), 71.3
(C-17), 111.5 (C-2), 113.8 (C-4), 126.3 (C-1), 132.3 (C-1P0), 137.8
(C-5), 157.5 (C-3).
Continued elution with CH2Cl2/hexane (1:1) resulted in 8a
(252 mg, 61%) as a white solid. The physical data were the same
as described in Section 2.5.
2.9. 3-Methoxy-17a
-[40-(4000-tolyl)-1H-1,2,3-triazol-1-yl]estr
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a-1,3,5(10)-triene (8b) and 3-methoxy-17a
-[40-(4000-tolyl)-
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2.6. 3-Methoxy-17a-(4-phenyl-1H-1,2,3-triazol-1-yl)estra-1,3,5(10)-t
riene (8a)
50-iodo-1H-1,2,3-triazol-1-yl]estra-1,3,5(10)-triene (9b)
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Compound 3 and 4-tolylacetylene (7b, 0.22 ml) were used for
the synthesis as described in Section 2.4. The crude product was
chromatographed on silica gel with CH2Cl2/hexane (1:3 v/v) as elu-
ent and crystallized from acetone to afford colorless crystalline 9b
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3-Methoxyestra-1,3,5(10)-trien-17a-azide (3) (312 mg, 1.00
mmol) was dissolved in CH2Cl2 (20 ml), and CuI (19 mg,
0.10 mmol), Ph3P (52 mg, 0.20 mmol) and phenylacetylene (7a,
0.22 ml, 2 mmol) were added. The mixture was stirred under reflux
for 24 h, and then diluted with water (30 ml) and extracted with
CH2Cl2 (2 ꢁ 30 ml). The combined organic phase was dried over
Na2SO4, and evaporated in vacuo. The crude product was purified
by flash chromatography with CH2Cl2/hexane (1:1 v/v) to yield
pure 8a (215 mg, 52%) as a white solid. Mp 230–232 °C; Rf = 0.50
(42 mg, 7.6%). Mp 212–214 °C; Rf = 0.70 (ss C); [a]
20 + 106 (c 1 in
D
CHCl3). (Found: C, 60.85; H, 5.72. C28H32IN3O requires C, 60.76;
H, 5.83%). 1H NMR (d, ppm): 1.06 (s, 3H, 18-H3), 2.41 (s, 3H,
tolyl-CH3), 2.86 (m, 2H, 6-H2), 3.76 (s, 3H, 3-OCH3), 4.79 (d, 1H,
J = 8.2 Hz, 17-H), 6.63 (d, 1H, J = 2.2 Hz, 4-H), 6.67 (dd, 1H,
J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.10 (d, 1H, J = 8.6 Hz, 1-H), 7.28 (d,
2H, J = 7.9 Hz, 30- and 50-H), 7.86 (d, 2H, J = 7.9 Hz, 20- and 60-H).
13C NMR (d, ppm): 18.7 (C-18), 21.3 (tolyl-CH3), 25.2, 26.1, 27.9,
29.2, 29.9, 32.8, 39.1, 42.9, 47.3, 48.6, 55.2 (3-OCH3), 70.0 (C-17),
(ss C); [a]
20 + 57 (c 1 in CHCl3). (Found C, 78.61; H, 7.43.
D
C27H31N3O requires C, 78.42; H, 7.56%.) 1H NMR (d, ppm): 1.00 (s,
3H, 18-H3), 2.87 (m, 2H, 6-H2), 3.76 (s, 3H, 3-OCH3), 4.68 (d, 1H,
J = 7.8 Hz, 17-H), 6.62 (d, 1H, J = 2.2 Hz, 4-H), 6.67 (dd,
1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.10 (d, 1H, J = 8.6 Hz, 1-H), 7.33 (t,
1H, J = 7.3 Hz, 40-H), 7.43 (d, 2H, J = 7.3 Hz, 30-and 50-H), 7.72
(s, 1H, C = CH), 7.87 (d, 2H, J = 7.3 Hz, 20- and 60-H). 13C NMR (d,
ppm): 18.7 (C-18), 24.9, 26.0, 28.0, 28.7, 29.8, 32.7, 39.2, 43.1,
46.6, 48.9, 55.2 (3-OCH3), 70.5 (C-17), 111.4 (C-2), 113.8 (C-4),
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78.8 (C = CI), 111.5 (C-2), 113.7 (C-4), 126.2 (C-1), 127.5 and
129.1 (2 ꢁ 2C: C-20, -30, -50, -60), 127.6 (C-10), 132.4 (C-10), 137.9
and 138.3 (C-5 and C-40), 148.8 (C = CI), 157.4 (C-3).
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Continued elution with CH2Cl2/hexane (1:1 v/v) resulted in 8b
(193 g, 45%) as a white solid. Mp 224–226 °C; Rf = 0.60 (ss C);
[a]
20 + 33 (c 1 in CHCl3). (Found C, 78.51; H, 7.92. C28H33N3O
D
119.9 (C = CH), 125.6 and 128.8 (2x2C: C-20, -30, -50, -60), 126.2
226
227
requires C 78.65; H, 7.78%.) 1H NMR (d, ppm): 1.00 (s, 3H,
18-H3), 2.38 (s, 3H, tolyl-CH3), 2.87 (m, 2H, 6-H2), 3.76 (s, 3H,
3-OCH3), 4.68 (dd, 1H, J = 8.4 Hz, J = 1.3 Hz, 17-H), 6.62 (d, 1H,
J = 2.2 Hz, 4-H), 6.67 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.10 (d,
1H, J = 8.6 Hz, 1-H), 7.23 (d, 2H, J = 7.9 Hz, 30- and 50-H), 7.67 (s,
1H, C = CH), 7.75 (d, 2H, J = 7.9 Hz, 20- and 60-H). 13C NMR (d,
ppm): 18.7 (C-18), 21.3 (tolyl-CH3), 24.9, 26.0, 28.0, 28.7, 29.8,
32.7, 39.2, 43.1, 46.6, 48.9, 55.2 (3-OCH3), 70.4 (C-17), 111.4
(C-1), 128.0 (C-40), 130.8 (C-10), 132.2 (C-10), 137.8 (C-5), 146.9
228
(C = CH), 157.5 (C-3).
229
230
2.7. General procedure for the synthesis of triazoles (8a–d, 9a–d,
10a–d and 11a–d) in the presence of Et3N
231
232
233
234
235
236
237
238
239
240
3-Methoxyestra-1,3,5(10)-trien-17a-azide (3) (312 mg, 1.00
mmol) or 3-methoxyestra-1,3,5(10)-trien-17b-azide (5) (312 mg,
1.00 mmol) was dissolved in CH2Cl2 (20 ml), and CuI (19 mg,
0.10 mmol), Et3N (0.2 ml, 2 mmol) and substituted acetylene
derivative (7a–d, 2 mmol) were added. The mixture was stirred
under reflux for 24 h, and then diluted with water (30 ml) and
extracted with CH2Cl2 (2 ꢁ 30 ml). The combined organic phases
were dried over Na2SO4, and evaporated in vacuo. The crude pro-
duct was purified by flash chromatography, using CH2Cl2/hexane
(1:3 v/v), CH2Cl2/hexane (1:1 v/v) or CH2Cl2/hexane (2:1 v/v).
(C-2), 113.8 (C-4), 119.5 (C = CH), 125.6 and 129.5 (2 ꢁ 2C: C-20,
293
294
-30, -50, -60), 126.3 (C-1), 128.0 (C-10), 132.3 (C-10), 137.8 (2C: C-5
and C-40), 147.0 (C = CH), 157.5 (C-3).
295
2.10. 3-Methoxy-17a
-(40-benzoyloxymethyl-1H-1,2,3-triazol-1-yl)est
296
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298
ra-1,3,5(10)-triene (8c) and 3-methoxy-17a
-(40-benzoyloxymethyl-5
0-iodo-1H-1,2,3-triazol-1-yl)estra-1,3,5(10)-triene (9c)
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304
305
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310
311
Compound 3 and propargyl benzoate (7c, 0.20 ml) were used
for the synthesis as described in Section 2.4. The crude product
was chromatographed on silica gel with CH2Cl2/hexane (1:1 v/v)
to yield pure 9c (39 mg, 5.5%) as a white solid. Mp 106–108 °C;
-(40-phenyl-1H-1,2,3-triazol-1-yl)estra-1,3,5(10)-
-(40-phenyl-50-iodo-1H-1,2,3-triazo
241
242
243
2.8. 3-Methoxy-17
triene (8a) and 3-methoxy-17
l-1-yl)estra-1,3,5(10)-triene (9a)
a
a
Rf = 0.70 (ss C); [a]
20 + 136 (c 1 in CHCl3). (Found C, 58.05; H,
D
5.54. C29H32IN3O3 requires C 58.30; H, 5.40%.) 1H NMR (d, ppm):
1.04 (s, 3H, 18-H3), 2.86 (m, 2H, 6-H2), 3.76 (s, 3H, 3-OCH3), 4.70
(dd, 1H, J = 7.9 Hz, J = 2.1 Hz, 17-H), 5.45 (d, 2H, J = 3.8 Hz, OCH2),
6.63 (d, 1H, J = 2.2 Hz, 4-H), 6.67 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz,
2-H), 7.09 (d, 1H, J = 8.6 Hz, 1-H), 7.44 (d, 2H, J = 7.7 Hz, 30- and
50-H), 7.56 (t, 1H, J = 7.7 Hz, 40-H), 8.07 (d, 2H, J = 7.7 Hz, 20- and
60-H). 13C NMR (d, ppm): 18.7 (C-18), 25.1, 26.0, 27.9, 29.2, 29.8,
32.7, 39.1, 42.9, 47.3, 48.5, 55.2 (3-OCH3), 58.3 (OCH2), 70.3
244
245
246
247
248
249
250
251
252
253
254
255
Compound 3 and phenylacetylene (7a, 0.22 ml) were used for
the synthesis as described in Section 2.4. The crude product was
chromatographed on silica gel with CH2Cl2/hexane (1:3 v/v) to
yield pure 9a (35 mg, 6.5%) as a white solid. Mp 226–228 °C;
Rf = 0.55 (ss C); [a]
20 + 153 (c 1 in CHCl3). (Found: C, 59.98; H,
D
5.78. C27H30IN3O requires C, 60.11; H, 5.61%.). 1H NMR (d, ppm):
1.07 (s, 3H, 18-H3), 2.87 (m, 2H, 6-H2), 3.77 (s, 3H, 3-OCH3), 4.81
(dd, 1H, J = 8.3 Hz, J = 1.8 Hz, 17-H), 6.63 (d, 1H, J = 2.2 Hz, 4-H),
6.68 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.10 (d, 1H, J = 8.6 Hz,
1-H), 7.40 (t, 1H, J = 7.3 Hz, 40-H), 7.48 (d, 2H, J = 7.3 Hz, 30- and
50-H), 7.98 (d, 2H, J = 7.3 Hz, 20- and 60-H). 13C NMR (d, ppm):
18.7 (C-18), 25.2, 26.1, 27.9, 29.2, 29.9, 32.8, 39.1, 42.9, 47.3,
312
313
(C-17), 83.3 (C = CI), 111.5 (C-2), 113.8 (C-4), 126.2 (C-1), 128.3
and 129.8 (2x2C: C-20, -30, -50, -60), 129.7 (C-10), 132.3 (C-10),
133.1 (C-40), 137.9 (C-5), 145.7 (C = CI), 157.4 (C-3), 166.2 (OCO).
Continued elution with CH2Cl2/hexane (2:1 v/v) resulted in 8c
(290 mg, 61.5%) as a white solid. Mp 160–162 °C; Rf = 0.60 (ss C);
314
315
316
317
318
319
256
257
48.6, 55.2 (3-OCH3), 70.0 (C-17), 79.1 (C = CI), 111.5 (C-2), 113.8
(C-4), 126.2 (C-1), 127.6 (2C) and 128.4 (3C): C-20, -30, -40, -50,
-60), 130.5 (C-10), 132.4 (C-10), 137.9 (C-5), 148.7 (C = CI), 157.4
(C-3).
[a]
20 + 33 (c 1 in CHCl3). (Found C, 73.98; H, 6.92. C29H33N3O3
D
requires C 73.86; H, 7.05%). 1H NMR (d, ppm): 0.98 (s, 3H,
258
259
18-H3), 2.85 (m, 2H, 6-H2), 3.76 (s, 3H, 3-OCH3), 4.64 (d, 1H,
Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018

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325
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382
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384
385
386
387
388
389
J = 8.1 Hz, 17-H), 5.49 (s, 2H, OCH2), 6.62 (d, 1H, J = 2.2 Hz, 4-H),
6.67 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.09 (d, 1H, J = 8.6 Hz,
1-H), 7.43 (t, 2H, J = 7.7 Hz, 30- and 50-H), 7.55 (t, 1H, J = 7.7 Hz,
40-H), 7.65 (s, 1H, C = CH), 8.05 (d, 2H, J = 7.7 Hz, 20- and 60-H).
13C NMR (d, ppm): 18.7 (C-18), 24.9, 25.9, 27.9, 28.7, 29.8, 32.6,
39.1, 43.1, 46.6, 48.8, 55.2 (3-OCH3), 58.2 (OCH2), 70.5 (C-17),
Continued elution with CH2Cl2 (3:1 v/v) yielded pure 10a
(236 mg, 57%) as a white solid. Mp 295–296 °C; Rf = 0.50 (ss C);
[a]
20 + 25 (c 1 in CHCl3). (Found C, 78.33; H, 7.62. C27H31N3O
D
requires C, 78.42; H, 7.56%.) 1H NMR (d, ppm, C6D6): 0.31 (s, 3H,
18-H3), 2.72 (m, 2H, 6-H2), 3.42 (s, 3H, 3-OCH3), 3.99 (t, 1H,
J = 9.6 Hz, 17-H), 6.72 (d, 1H, J = 2.2 Hz, 4-H), 6.79 (dd, 1H,
J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.00 (m, 2H) and 7.25–7.31 (overlapping
multiplets, 5H): 1-H, C = CH, 30-, 40- and 50-H; 8.02 (d, 2H, J = 7.5 Hz,
20- and 60-H). 13C NMR (d, ppm): 16.7 (C-18), 21.3, 23.0, 27.0, 27.7,
29.8, 32.7, 39.2, 40.1, 44.6, 49.9, 55.0 (3-OCH3), 70.7 (C-17), 111.8
326
327
111.5 (C-2), 113.7 (C-4), 124.3 (C = CH), 126.2 (C-1), 128.4 and
129.8 (2 ꢁ 2C: C-20, -30, -50, -60), 129.7 (C-10), 132.2 (C-10), 133.1
(C-40), 137.8 (C-5), 142.1 (C = CH), 157.5 (C-3), 166.5 (OCO).
328
(C-2), 114.2 (C-4), 120.9 (C = CH), 127.8 and 129.8 (2 ꢁ 2C: C-20,
390
391
2.11. 3-Methoxy-17a
-[40-(4000-toluoyloxymethyl)-1H-1,2,3-triazol-1-y
329
330
331
-30, -50, -60), 127.2 (C-1), 129.0 (C-40), 133.8 (C-10), 134.2 (C-10),
l]estra-1,3,5(10)-triene (8d) and 3-methoxy-17a
-[40-(4000-toluoyloxy
392
139.1 (C-5), 148.9 (C = CH), 158.5 (C-3).
methyl)-50-iodo-1H-1,2,3-triazol-1-yl]estra-1,3,5(10)-triene (9d)
2.13. 3-Methoxy-17b-[40-(4000-tolyl)-1H-1,2,3-triazol-1-yl]estr
a-1,3,5(10)-triene (10b) and 3-methoxy-17b-[40-(4000-tolyl)-
50-iodo-1H-1,2,3-triazol-1-yl)estra-1,3,5(10)-triene (11b)
332
333
334
335
336
337
338
339
340
341
342
343
344
Compound 3 and propargyl 4-methylbenzoate (7d, 0.20 ml)
were used for the synthesis as described in Section 2.4. The crude
product was chromatographed on silica gel with CH2Cl2/hexane
(1:1 v/v) to yield pure 9d (61 mg, 7.8%) as a white solid. Mp
393
394
395
192–194 °C; Rf = 0.75 (ss C); [a]
20 + 128 (c 1 in CHCl3). (Found C,
D
396
397
398
399
400
401
402
403
404
405
406
407
Compound 5 and 4-tolylacetylene (7b, 0.22 ml) were used for
the synthesis as described in Section 2.4. The crude product was
chromatographed on silica gel with CH2Cl2/hexane (2:1 v/v) to
59.06; H, 5.72. C30H34IN3O3 requires C 58.92; H, 5.60%.) 1H NMR
(d, ppm): 1.04 (s, 3H, 18-H3), 2.40 (s, 3H, tolyl-CH3), 2.86 (m, 2H,
6-H2), 3.76 (s, 3H, 3-OCH3), 4.70 (m, 1H, 17-H), 5.43 (d, 2H,
J = 3.0 Hz, OCH2), 6.63 (d, 1H, J = 2.2 Hz, 4-H), 6.67 (dd, 1H,
J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.09 (d, 1H, J = 8.6 Hz, 1-H), 7.23 (d,
2H, J = 7.9 Hz, 30- and 50-H), 7.96 (d, 2H, J = 7.9 Hz, 20- and 60-H).
13C NMR 18.7 (C-18), 21.7 (tolyl-CH3), 25.2, 26.0, 27.9, 29.2, 29.8,
32.7, 39.1, 42.9, 47.3, 48.5, 55.2 (3-OCH3), 58.2 (OCH2), 70.2
yield pure 11b (34 mg, 6.2%) as a white crystalline form. Mp
20
188–190 °C; Rf = 0.75 (ss C); [
a]
-71 (c 1 in CHCl3). (Found C,
D
60.47; H, 5.94. C28H32IN3O requires C, 60.76; H, 5.83%.) 1H NMR
(d, ppm): 0.83 (s, 3H, 18-H3), 2.41 (s, 3H, tolyl-CH3), 2.90 (m, 2H,
6-H2), 3.78 (s, 3H, 3-OCH3), 4.67 (t, 1H, J = 9.4 Hz, 17-H), 6.65 (d,
1H, J = 2.2 Hz, 4-H), 6.70 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.18
(d, 1H, J = 8.6 Hz, 1-H), 7.28 (d, 2H, J = 7.9 Hz, 30- and 50-H), 7.83
(d, 2H, J = 7.9 Hz, 20- and 60-H). 13C NMR (d, ppm): 13.0 (C-18),
21.3 (tolyl-CH3), 23.3, 26.3, 27.2, 27.4, 29.8, 38.3, 38.8, 43.7, 46.1,
345
346
(C-17), 83.3 (C = CI), 111.5 (C-2), 113.8 (C-4), 126.1 (C-1), 127.0
(C-10), 129.0 and 129.9 (2 ꢁ 2C: C-20, -30, -50, -60), 132.3 (C-10),
137.9 (C-5), 143.8 (C-40), 145.8 (C = CI), 157.4 (C-3), 166.3 (OCO).
Continued elution with CH2Cl2/hexane (2:1 v/v) yielded pure 8d
(306 mg, 63%) as a white solid. Mp 136–138 °C; Rf = 0.65 (ss C);
347
348
349
350
351
352
353
354
355
356
357
358
408
409
410
52.5, 55.2 (3-OCH3), 70.1 (C-17), 78.3 (C = CI), 111.5 (C-2), 113.8
(C-4), 126.2 (C-1), 127.7 and 129.1 (2x2C: C-20, -30, -50, -60), 128.2
(C-10), 132.1 (C-10), 137.8 and 138.3 (C-5 and C-40), 149.3
[a]
20 + 30 (c 1 in CHCl3). (Found C, 74.08; H, 7.41%. C30H35N3O3
D
requires C, 74.20; H, 7.26%.) 1H NMR (d, ppm): 0.97 (s, 3H,
18-H3), 2.39 (s, 3H, tolyl-CH3), 2.86 (m, 2H, 6-H2), 3.76 (s, 3H,
3-OCH3), 4.64 (d, 1H, J = 8.0 Hz, 17-H), 5.48 (s, 2H, OCH2), 6.62 (d,
1H, J = 2.2 Hz, 4-H), 6.67 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.09
(d, 1H, J = 8.6 Hz, 1-H), 7.21 (d, 2H, J = 7.9 Hz, 30- and 50-H), 7.64
(s, 1H, C = CH), 7.93 (d, 2H, J = 7.9 Hz, 20- and 60-H). 13C NMR (d,
ppm): 18.7 (C-18), 21.6 (tolyl-CH3), 24.9, 25.9, 27.9, 28.7, 29.8,
32.6, 39.1, 43.1, 46.6, 48.8, 55.2 (3-OCH3), 58.1 (OCH2), 70.5
411
412
413
414
415
416
417
418
419
420
421
422
423
(C = CI), 157.5 (C-3).
Continued elution with CH2Cl2 yielded pure 10b (285 mg, 67%)
as a white solid. Mp 310–312 °C; Rf = 0.60 (ss C); [a]
20 + 17 (c 1 in
D
CHCl3). (Found C, 78.53; H, 7.89. C28H33N3O requires C, 78.65; H,
7.78%.)
1H NMR (d, ppm, C6D6): 0.31 (s, 3H, 18-H3), 2.47 (s, 3H,
tolyl-CH3), 2.72 (m, 2H, 6-H2), 3.41 (s, 3H, 3-OCH3), 3.99 (t, 1H,
J = 9.6 Hz, 17-H), 6.72 (d, 1H, J = 2.2 Hz, 4-H), 6.80 (dd, 1H,
J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.26 (d, 1H, J = 8.6 Hz, 1-H), 7.25 (over-
lapping multiplets, 3H, 30-, 40- and 50-H), 7.31 (s, 1H, C = CH), 8.03
(d, 2H, J = 7.5 Hz, 20- and 60-H). 13C NMR (d, ppm): 16.5 (C-18),
21.5 (tolyl-CH3), 21.7, 22.9, 28.0, 29.7, 30.3, 32.7, 39.6, 42.1, 46.9,
50.0, 55.5 (3-OCH3), 70.6 (C-17), 111.9 (C-2), 114.5 (C-4), 120.5
359
360
(C-17), 111.5 (C-2), 113.8 (C-4), 124.3 (C = CH), 126.2 (C-1), 127.1
(C-10), 129.1 and 129.8 (2 ꢁ 2C: C-20, -30, -50, -60), 132.1 (C-10),
137.8 (C-5), 142.3 (C = CH), 143.9 (C-40), 157.5 (C-3), 166.6 (OCO).
361
2.12. 3-Methoxy-17b-(40-phenyl-1H-1,2,3-triazol-1-yl)estr
a-1,3,5(10)-triene (10a) and 3-methoxy-17b-(40-phenyl-
50-iodo-1H-1,2,3-triazol-1-yl)estra-1,3,5(10)-triene (11a)
362
363
364
(C = CH), 127.8 and 129.9 (2x2C: C-20, -30, -50, -60), 129.3 (C-1),
424
425
132.0 (C-10), 134.3 (C-10), 138.8 (2C: C-5 and C-40), 148.6
426
(C = CH), 158.3 (C-3).
365
366
367
368
369
370
371
372
373
374
375
376
Compound 5 and phenylacetylene (7a, 0.22 ml) were used for
the synthesis as described in Section 2.4. The crude product was
chromatographed on silica gel with CH2Cl2/hexane (1:1 v/v) to
2.14. 3-Methoxy-17b-(40-benzoyloxymethyl-1H-1,2,3-triazol-1-yl)est
ra-1,3,5(10)-triene (10c) and 3-methoxy-17b-(40-benzoyloxymethy
l-50-iodo-1H-1,2,3-triazol-1-yl)estra-1,3,5(10)-triene (11c)
427
428
429
yield pure 11a (42 mg, 7.7%) as a white solid. Mp 148–150 °C;
20
Rf = 0.60 (ss C); [
a]
-85 (c 1 in CHCl3). (Found C, 60.23; H, 5.43.
D
C27H30IN3O requires C, 60.11; H, 5.61%.) 1H NMR (d, ppm): 0.83
(s, 3H, 18-H3), 2.89 (m, 2H, 6-H2), 3.78 (s, 3H, 3-OCH3), 4.69 (t,
1H, J = 9.3 Hz, 17-H), 6.65 (d, 1H, J = 2.2 Hz, 4-H), 6.71 (dd, 1H,
J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.19 (d, 1H, J = 8.6 Hz, 1-H), 7.40 (t, 1H,
J = 7.3 Hz, 40-H), 7.48 (d, 2H, J = 7.3 Hz, 30- and 50-H), 7.95 (d, 2H,
J = 7.3 Hz, 20- and 60-H). 13C NMR (d, ppm): 13.0 (C-18), 23.3,
26.3, 27.2, 27.4, 29.7, 38.3, 38.8, 43.7, 46.1, 52.5, 55.2 (3-OCH3),
430
431
432
433
434
435
436
437
438
439
Compound 5 and propargyl benzoate (7c, 0.20 ml) were used
for the synthesis as described in Section 2.4. The crude product
was chromatographed on silica gel with CH2Cl2/hexane (1:1 v/v)
to yield pure 11c (40 mg, 6.7%) as a white solid. Mp 155–156 °C;
20
Rf = 0.60 (ss C); [
a
]
D
-73 (c 1 in CHCl3). (Found C, 58.16; H, 5.57.
C29H32IN3O3 requires C, 58.30; H, 5.40%.) 1H NMR (d, ppm): 0.80
(s, 3H, 18-H3), 2.88 (m, 2H, 6-H2), 3.78 (s, 3H, 3-OCH3), 4.57 (m,
1H, 17-H), 5.45 (d, 2H, J = 4.8 Hz, OCH2), 6.65 (d, 1H, J = 2.2 Hz,
4-H), 6.70 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.17 (d, 1H,
J = 8.6 Hz, 1-H), 7.43 (t, 2H, J = 7.3 Hz, 30- and 50-H), 7.56 (t, 1H,
377
378
70.2 (C-17), 78.6 (C = CI), 111.5 (C-2), 113.8 (C-4), 126.2 (C-1),
127.8 (2C) and 128.4 (3C): C-20, -30, -40, -50, -60), 130.5 (C-10),
379
132.1 (C-10), 137.8 (C-5), 149.2 (C = CI), 157.5 (C-3).
Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018

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J = 7.3 Hz, 40-H), 8.07 (d, 2H, J = 7.3 Hz, 20- and 60-H). 13C NMR (d,
ppm):13.0 (C-18), 23.3, 26.3, 27.1, 27.4, 29.7, 38.3, 38.8, 43.7,
2 mmol), substituted acetylene derivative (7a–d, 2 mmol), ICl
(1.5 mmol) and finally CuI (190 mg, 10 mmol) were added. The
heterogenous reaction mixture was stirred under N2 for 24 h, and
then diluted with 1% Na2S2O3 solution (30 ml), and extracted with
CH2Cl2 (2 ꢁ 30 ml). The combined organic phases were dried over
Na2SO4, and evaporated in vacuo. The crude product was purified
by flash chromatography, using CH2Cl2/hexane (1:3 v/v), which
eluted the starting material (3 or 5) and then CH2Cl2/hexane
(1:1) to obtain the steroidal 50-iodotriazoles (9a-d and 11a-d).
440
441
500
501
502
503
504
505
506
507
508
442
443
444
46.1, 52.5, 55.2 (3-OCH3), 58.3 (OCH2), 70.5 (C-17), 82.9 (C = CI),
111.6 (C-2), 113.8 (C-4), 126.2 (C-1), 128.3 and 129.8 (2x2C: C-20,
-30, -50, -60), 129.7 (C-10), 132.0 (C-10), 133.1 (C-40), 137.8 (C-5),
445
446
447
448
449
450
451
452
453
454
455
456
146.0 (C = CI), 157.6 (C-3), 166.2 (OCO).
Continued elution with CH2Cl2/hexane (2:1 v/v) yielded pure
10c (292 mg, 62%) as a white solid. Mp 139–141 °C; Rf = 0.55 (ss
C); [a]
20+20 (c 1 in CHCl3). (Found C, 73.62; H, 6.91. C29H33N3O3
D
requires C, 73.86; H, 7.05%.) 1H NMR (d, ppm): 0.59 (s, 3H,
18-H3), 2.88 (m, 2H, 6-H2), 3.77 (s, 3H, 3-OCH3), 4.50 (t, 1H,
J = 9.6 Hz, 17-H), 5.49 (s, 2H, OCH2), 6.64 (d, 1H, J = 2.2 Hz, 4-H),
6.70 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.18 (d, 1H, J = 8.6 Hz,
1-H), 7.43 (t, 2H, J = 7.3 Hz, 30- and 50-H), 7.56 (t, 1H, J = 7.3 Hz,
40-H), 7.71 (s, 1H, C = CH), 8.05 (d, 2H, J = 7.3 Hz, 20- and 60-H).
13C NMR (d, ppm): 12.2 (C-18), 23.1, 26.0, 26.2, 27.3, 29.7, 37.0,
38.8, 43.8, 44.8, 51.9, 55.2 (3-OCH3), 58.2 (OCH2), 70.7 (C-17),
2.17. 3-Methoxy-17a
-(40-phenyl-50-iodo-1H-1,2,3-triazol-1-yl)estr
a-1,3,5(10)-triene (9a)
509
510
511
512
513
514
Compound 3 and phenylacetylene (7a) were used for the syn-
thesis as described in Section 2.15. After purification, 9a was
obtained as a white solid (485 mg, 89%). The physical data were
the same as described in Section 2.8.
457
458
111.5 (C-2), 113.8 (C-4), 123.5 (C = CH), 126.3 (C-1), 128.3 and
2.18. 3-Methoxy-17a
-[40-(4000-tolyl)-50-iodo-1H-1,2,3-triazol-1-yl]estr
a-1,3,5(10)-triene (9b)
515
516
129.7 (2 ꢁ 2C: C-20, -30, -50, -60), 129.6 (C-10), 132.1 (C-10), 133.1
(C-40), 137.7 (C-5), 142.1 (C = CH), 157.5 (C-3), 166.5 (OCO).
459
517
518
519
520
Compound 3 and 4-tolylacetylene (7b) were used for the syn-
thesis as described in Section 2.15. After purification, 9b was
obtained as a white solid (510 mg, 92%). The physical data were
the same as described in Section 2.9.
2.15. 3-Methoxy-17b-[40-(4000-toluoyloxymethyl)-1H-1,2,3-triazol-1-y
l]estra-1,3,5(10)-triene (10d) and 3-methoxy-17b-[40-(4000-toluoyloxy
methyl)-50-iodo-1H-1,2,3,-triazol-1-yl]estra-1,3,5(10)-triene (11d)
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
Compound 5 and propargyl 4-methylbenzoate (7d, 0.20 ml)
were used for the synthesis as described in Section 2.4. The crude
product was chromatographed on silica gel with CH2Cl2/hexane
2.19. 3-Methoxy-17a
-(40-benzoyloxymethyl-50-iodo-1H-1,2,3-triazo
l-1-yl)estra-1,3,5(10)-triene (9c)
521
522
(1:1 v/v) to yield pure 11d (46 mg, 7.5%) as a white solid. Mp
523
524
525
526
Compound 3 and propargyl benzoate (7c) were used for the
synthesis as described in Section 2.15. After purification, 9c was
obtained as a white solid (512 mg, 85%). The physical data were
the same as described in Section 2.10.
20
180–182 °C; Rf = 0.65 (ss C); [
a]
-74 (c 1 in CHCl3). (Found C,
D
58.83; H, 5.46. C30H34IN3O3 requires C, 58.92; H, 5.60%). 1H NMR
(d, ppm): 0.80 (s, 3H, 18-H3), 2.40 (s, 3H, tolyl-CH3), 2.89 (m, 2H,
6-H2), 3.78 (s, 3H, 3-OCH3), 4.57 (t, 1H, J = 9.5 Hz, 17-H), 5.43 (d,
2H, J = 4.8 Hz, OCH2), 6.65 (d, 1H, J = 2.2 Hz, 4-H), 6.70 (dd, 1H,
J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.18 (d, 1H, J = 8.6 Hz, 1-H), 7.22 (d,
2H, J = 7.3 Hz, 30- and 50-H), 7.96 (d, 2H, J = 7.3 Hz, 20- and 60-H).
13C NMR (d, ppm): 13.0 (C-18), 22.0 (tolyl-CH3), 23.3, 26.3, 27.1,
27.3, 29.7, 38.3, 38.8, 43.7, 46.1, 52.5, 55.2 (3-OCH3), 58.2 (OCH2),
2.20. 3-Methoxy-17a
-(40-toluoyloxymethyl-50-iodo-1H-1,2,3-triazo
l-1-yl)estra-1,3,5(10)-triene (9d)
527
528
529
530
531
532
Compound 3 and propargyl 4-methylbenzoate (7d) were used
for the synthesis as described in Section 2.15. After purification,
9d was obtained as a white solid (503 mg, 82%). The physical data
were the same as described in Section 2.11.
476
477
70.5 (C-17), 82.8 (C = CI), 111.5 (C-2), 113.8 (C-4), 126.2 (C-1),
127.0 (C-10), 129.0 and 129.9 (2x2C: C-20, -30, -50, -60), 132.0
(C-10), 137.8 (C-5), 143.8 (C-40), 146.0 (C = CI), 157.5 (C-3), 166.3
(OCO).
478
479
480
481
482
483
484
485
486
487
488
489
490
2.21. 3-Methoxy-17b-(40-phenyl-50-iodo-1H-1,2,3-triazol-1-yl)estr
a-1,3,5(10)-triene (11a)
533
534
Continued elution with CH2Cl2/hexane (2:1 v/v) yielded pure
10d (282 mg, 58%) as a white solid. Mp 172–174 °C; Rf = 0.60 (ss
C); [a]
20 + 24 (c 1 in CHCl3). (Found C, 74.05; H, 7.38. C30H35N3O3
D
535
536
537
538
Compound 5 and phenylacetylene (7a) were used for the syn-
thesis as described in Section 2.15. After purification, 11a was
obtained as a white solid (492 mg, 91%). The physical data were
the same as described in Section 2.12.
requires C, 74.20; H, 7.26%.) 1H NMR (d, ppm): 0.58 (s, 3H,
18-H3), 2.40 (s, 3H, tolyl-CH3), 2.88 (m, 2H, 6-H2), 3.77 (s, 3H,
3-OCH3), 4.50 (t, 1H, J = 9.5 Hz, 17-H), 5.47 (s, 2H, OCH2), 6.64 (d,
1H, J = 2.2 Hz, 4-H), 6.70 (dd, 1H, J = 8.6 Hz, J = 2.2 Hz, 2-H), 7.18
(d, 1H, J = 8.6 Hz, 1-H), 7.22 (d, 2H, J = 7.3 Hz, 30- and 50-H), 7.71
(s, 1H, C = CH), 7.94 (d, 2H, J = 7.3 Hz, 20- and 60-H). 13C NMR (d,
ppm): 12.2 (C-18), 21.6 (tolyl-CH3), 23.1, 26.0, 26.2, 27.4, 29.7,
36.9, 38.8, 43.8, 44.7, 51.9, 55.2 (3-OCH3), 58.1 (OCH2), 70.7
2.22. 3-Methoxy-17b-[40-(4000-tolyl)-50-iodo-1H-1,2,3-triazol-1-yl]estr
a-1,3,5(10)-triene (11b)
539
540
541
542
543
544
Compound 5 and 4-tolylacetylene (7b) were used for the syn-
thesis as described in Section 2.15. After purification, 11b was
obtained as a white solid (515 mg, 93%). The physical data were
the same as described in Section 2.13.
491
492
(C-17), 111.5 (C-2), 113.8 (C-4), 123.5 (C = CH), 126.3 (C-1), 127.1
(C-10), 129.0 and 129.8 (2 ꢁ 2C: C-20, -30, -50, -60), 132.0 (C-10),
137.7 (C-5), 142.2 and 143.8 (C = CH and C-40), 157.5 (C-3), 166.6
(OCO).
493
494
2.23. 3-Methoxy-17b-(40-benzoyloxymethyl-50-iodo-1H-1,2,3-triazo
l-1-yl)estra-1,3,5(10)-triene (11c)
545
546
2.16. General procedure for the synthesis of 50-iodotriazoles (9a-9d
and 11a-11d)
495
496
547
548
549
550
Compound 5 and propargyl benzoate (7c) were used for the
synthesis as described in Section 2.15. After purification, 11c was
obtained as a white solid (498 mg, 83%). The physical data were
the same as described in Section 2.14.
497
498
499
3-Methoxyestra-1,3,5(10)-trien-17a-azide (3) (312 mg, 1.00
mmol) or 3-methoxyestra-1,3,5(10)-trien-17b-azide (5) (312 mg,
1 mmol) was dissolved in CH2Cl2 (15 ml), and Et3N (0.2 ml,
Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018

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G. Schneider et al. / Steroids xxx (2015) xxx–xxx
2.24. 3-Methoxy-17b-[40-(4000-toluoyloxymethyl)-50-iodo-1H-1,2,3-tri
azol-1-yl]estra-1,3,5(10)-triene (11d)
MTT was assayed at 545 nm, using a microplate reader; wells with
untreated cells were utilized as controls [27]. Sigmoidal dose–re-
sponse curves were fitted to the determined data and the IC50 val-
ues (the concentration at which the extent of cell proliferation was
half that of the untreated control) were calculated by means of
GraphPad Prism 4.0 (GraphPad Software, San Diego, CA, USA). All
in vitro experiments were carried out on two microplates with at
least five parallel wells. Cisplatin was used as positive control.
Stock solutions of the tested substances (10 mM) were prepared
with DMSO. The highest DMSO content of the medium (0.3%) did
not have any substantial effect on the cell proliferation.
551
552
612
613
614
615
616
617
618
619
620
621
622
553
554
555
556
Compound 5 and propargyl 4-methylbenzoate (7d) were used
for the synthesis as described in Section 2.15. After purification
11d was obtained as a white solid (528 mg, 86%). The physical data
were the same as described in Section 2.15.
557
2.25. Single-crystal X-ray diffraction of 9b
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
Crystal data: C28H32IN3O, Fwt.: 553.47, colorless, prism, size:
0.75
x
0.25
x
0.10 mm, monoclinic, space group
P
21,
a = 10.1759(2) Å, b = 7.11640(10) Å, c = 18.2809(3) Å,
a
= 90°,
= 90°, V = 1299.92(4) Å3, T = 295(2) K, Z = 2,
3. Results and discussion
623
624
b = 100.9050(10)°,
c
Dx = 1.414 Mg/m3. A crystal of 9b was mounted on a loop. Cell
parameters were determined by least-squares using 12629
(6.69 6 h 6 66.54°) reflections. Intensity data were collected on
3.1. Synthetic studies
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
an R-AXIS-RAPID diffractometer (graphite monochromator Cu-K
a
To prepare novel steroid triazoles via 1,3-dipolar cycloaddition,
17a- and 17b-azido-estrone-3-methyl ether (3 and 5) were chosen
radiation, k = 1.54187 Å) at 293(2)
K
in the range 6.69 6 h
6 66.54o; CrystalClear SM 1.4.0 Programs for data collection and
reduction (Rigaku/MSC Inc., 2008). A total of 13464 reflections
were collected, of which 4157 were unique [R(int) = 0.0512,
as starting compounds. The synthetic strategy for the preparation
of the starting azides is illustrated in Scheme 1, and the synthesis
of steroidal 1,2,3-triazoles by CuAAC is outlined in Scheme 2.
Stereoselective reduction of 3-methoxyestrone (1) leading to
3-methoxyestra-17b-ol (2a) was followed by tosylation to give
2b, which then underwent facile SN2 substitution with NaN3 in
N,N-dimethylformamide to furnish the corresponding 17
compound 3 [19]. The iodination of 2a by the Appel reaction [28]
proceeded with Walden inversion to yield 3-methoxy-17
R(r) = 0.0631]; intensities of 3906 reflections were greater than
2r(I). Completeness to h = 0.950. A numerical absorption correc-
tion was applied to the data (the minimum and maximum trans-
mission factors were 0.051 and 0.443). The structure was solved
by direct methods [24] and subsequent difference syntheses.
Anisotropic full-matrix least-squares refinement on F2 for all
non-hydrogen atoms yielded R1=0.0388 and wR2 = 0.0922 for
a-azido
a-
iodoestrane (4). The further nucleophilic exchange reaction with
NaN3 in N,N-dimethylformamide furnished the 17b-azido com-
pound 5 in moderate yield. The exchange reaction was accompa-
nied by elimination to give 3-methoxyestra-16-ene (6) too.
The CuAAC of 3 with phenylacetylene (7a) was carried out in
refluxing CH2Cl2 with CuI as catalyst in the presence of PhP3 (0.2
equivalent) at room temperature to obtain the required 1,
4-disubstituted triazole (8) in moderate yield after 24 h (Table 1,
entry 1).
Ph3P is assumed to accelerate the rate of the reaction and to
improve the solubility of the catalyst by complexing to CuI, since
no appreciable transformation was noted without its addition to
the reaction mixture. The application of CuI in such reactions is
known to require high temperature or at least an amine base
additive such as Et3N or N,N-diisopropylethylamine for adequate
formation of the Cu-acetylide complex. Moreover, certain com-
plexing ligands are often employed in order to enhance the activity
of the catalyst and to protect the CuI from oxidation [29].
To accelerate the CuAAC process and increase the yield of the
required 1,4-substituted triazoles, Ph3P was replaced by Et3N. In
the presence of Et3N, the TLC chromatogram showed not only the
1,4-triazoles (8a–d and 10a–d), but also new compounds (9a–d
and 11a–d) in very low concentrations (Table 1, entries 2–9).
In the case of the reaction described in Section 2.8, analytical
determination after chromatographic separation indicated that
the compound present in very low concentration was the
50-iodo-1,4-disubstituted triazole (9b).
1332 [I > 2r
(I)] and R1 = 0.0421 and wR2 = 0.0943 for all (4157)
intensity data, number of parameters = 301, goodness-of-
fit = 1.08, absolute structure parameter x = 0.045(8) [25]. The max-
imum and minimum residual electron density in the final differ-
ence map were 0.47 and ꢀ1.41 e Åꢀ3. Hydrogen atomic positions
were calculated from assumed geometries. Hydrogen atoms were
included in structure factor calculations, but were not refined.
The isotropic displacement parameters of the hydrogen atoms
were approximated from the U(eq) value of the atom they were
bonded to. Comparison of the experimental powder X-ray diffrac-
togram with a calculated one from the final single-crystal structure
confirmed the identity of the crystal with that of the bulk material
[26]. All pertinent further calculations, molecular graphics, etc.
were performed by using program PLATON and Mercury.
591
2.26. Determination of antiproliferative activities
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
The antiproliferative properties of the prepared triazolyles-
tranes were determined on a panel of human adherent cancer cell
lines of gynecological origin. MCF7, MDA-MB-36, MDA-MB-231
and T47D cells were isolated from breast cancer, while A2780
and HeLa cells were from ovarian and cervical cancer, respectively.
All cell lines were purchased from European Collection of Cell
Cultures (ECCAC, Salisbury, UK). Cells were cultivated in minimal
essential medium supplemented with 10% fetal bovine serum, 1%
non-essential amino acids and an antibiotic–antimycotic mixture.
All media and supplements were obtained from PAA Laboratories
GmbH, Pasching, Austria. Near-confluent cancer cells were seeded
onto a 96-well microplate (5000 cells/well) and, after overnight
X-ray structure analysis of one representative compound (9b)
demonstrated the presence of iodine in the molecule (Fig. 1).
Large displacement parameters at C(6) indicate puckering in
ring B. As it was not feasible to split this site for alternative posi-
tions, we adopted a single atom final model. Accordingly, ring B
has a distorted twist chair form, while ring C is an almost regular
chair form and the puckering of ring D involves twisting on
C(13)–C(14). The other rings are planar, as expected. Apart from
standing, new medium (200 ll) containing the tested compounds
was added. After incubation for 72 h at 37 °C in humidified air con-
taining 5% CO2, the living cells were assayed by addition of
5 mg mlꢀ1 MTT solution (20
ll). MTT was converted by intact
mitochondrial reductase and precipitated as blue crystals during
a 4-h contact period. The medium was then removed and the pre-
cipitated formazan crystals were dissolved in DMSO (100
ing a 60-min period of shaking at 25 °C. Finally, the reducted
shape and constitutions, the crystal structure reveals
a few
l
l) dur-
non-trivial intermolecular short contacts. The rather short
I10ꢂ ꢂ ꢂN30[x,y-1,z] distance of 2.912(8) Å demands mention. This is
Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018

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G. Schneider et al. / Steroids xxx (2015) xxx–xxx
7
OR
O
N3
iii
H
H
H
i
H
H
H
H
H
H
H3CO
H3CO
H3CO
3
1
R
2
H
a
b
ii
Ts
N3
iv
H
H
H
H
H
I
H3CO
H3CO
5
v
H
H
H
H3CO
H
4
6
Scheme 1. Reagents and conditions: (i) KBH4, MeOH; (ii); TsCl, pyridine, rt, 24 h; (iii) NaN3, DMF, 100 °C, 24 h; (iv) Ph3P, imidazole, I2, toluene, 80 °C, 2 h; (v) NaN3, DMF,
60 °C, 24 h.
R
R
N
N
N
N
N3
N
N
I
R
C
CH
H
H
H
7a-d
+
i
H
H
H
H
H
H
H3CO
H3CO
H3CO
3
8
9
R
R
N
N
N
N
N3
N
N
I
R
C
CH
H
H
H
7a-d
+
i
H
H
H
H
H
H
R
H3CO
H3CO
H3CO
5
10
11
ii
7-11
a
Ph
b
4-tolyl
H2C
c
O
C
Ph
O
d
H2C
O
C
4-tolyl
O
Scheme 2. Reagents and conditions: (i) Ph3P or Et3N, CuI, CH2Cl2, rt, 24 h; (ii) Et3N, CuI, ICl, CH2Cl2, rt, 24 h.
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
shorter by 0.62 Å than the sum of the van der Waals radii, and is
also interesting relative to the I10 C50 bond length of
terminus is supported by a second C700 – H7B0ꢂ ꢂ ꢂO1 short contact,
also with nearly ideal H-bridge conditions.
The geometry of these interactions that may be responsible for
the formation of the 9b crystal is illustrated in Fig. 2. This shows an
additional possibility of a C – H ꢂ ꢂ ꢂ / interaction between adjacent
p-toluene rings involving C30 – H as donor atoms.
Although iodo-containing triazoles are sometimes reported as
minor products in various CuAAC reactions in the presence of
DMAP (4-dimethylaminopyridine), there have been no reports of
the ability of any organic base to control the product distribution
in alkyne-azide cycloadditions. During some Cu-promoted
–
2.075(10) Å. A further interesting feature of this short approach
is the N30[x,yꢀ1,z] ꢂ ꢂ ꢂ I10 – C50 angle of 161.8(2)°. This indicates a
co-linear approach mimicking an SN attack on the largely asym-
metric electron cloud of the halogen atom [30]. This may make
an essential contribution to the formation of this crystal, as it rep-
resents an infinite one-dimensional chain with a [0 1 0] base
vector. In accord with this idea, another electrophilic C700
–
H7C0ꢂ ꢂ ꢂI10 short contact develops (Table 2) at 94° to the nucle-
ophilic contact. This short contact from a virtually labile methyl
Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018

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G. Schneider et al. / Steroids xxx (2015) xxx–xxx
Table 1
Syntheses of triazoles (8–11).
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
Cu-triazolyl intermediate with electrophilic halogen. The incorpo-
ration of iodine onto the triazole moiety usually requires the pres-
ence of electrophilic iodine (I+) to produce 5-iodotriazoles, but this
aerobic oxidative halogenation in CuAAC reactions is very sluggish
[32]. Fokin et al. recently reported that 1-iodoalkynes, which are
stable and readily accessible internal acetylenes, exhibit exception-
al reactivity in Cu-catalyzed annulation reactions with organic
azides to produce 5-iodo-1,2,3-triazoles [33]. Although several
syntheses of iodotriazoles are known, the reaction requires
stoichiometric amounts of Cu catalysts and employs reactive
electrophilic halogenating reagents, e.g. I2 or ICl [34],
N-bromosuccinimide or N-iodosuccinimide [35]. Moreover, some
procedures require extended reaction times and generate mixtures
of 5-H and 5-iodotriazoles [36]. An effective synthetic protocol for
Entry
Substrate
Alkyne
Conditions
Product
Yielda (%)
b
c
c
c
c
c
c
c
c
d
e
e
e
e
e
e
e
e
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
3
3
3
3
3
5
5
5
5
3
3
3
3
3
5
5
5
5
7a
7a
7b
7c
7d
7a
7b
7c
7d
7a
7a
7b
7c
7d
7a
7b
7c
7d
8a
52
8a + 9a
8b + 9b
8c + 9c
8d + 9d
10a + 11a
10b + 11b
10c + 11c
10d + 11d
8a + 9a
9a
9b
9c
9d
11a
11b
11c
11d
61 + 6.5
45 + 7.6
61 + 5.5
63 + 7.8
57 + 7.7
67 + 6.2
62 + 6.7
58 + 7.5
42 + 21
89
92
85
82
91
93
83
86
5-halotriazoles
involving
novel
tert-butyldimethylsi
lylchloride-activated aerobic oxidative halogenations has been
introduced [37], and an improved method has been developed
for the preparation of 5-iodotriazoles, in which coupling of an
organic azide with a terminal alkyne in the presence of Cu(ClO4)2
and an alkali metal iodide under mild conditions gives the required
5-iodo compound [38].
Since triazolyl derivatives attached to the sterane skeleton
have been reported to exhibit antiproliferative activity [19–21], it
appeared interesting to investigate the formation of
5-iodotriazoles. On the basis of the observations of Wu et al. [34]
relating to the production of 5-iodotriazoles, we increased the
quantity of Cu catalyst to one equivalent, but the quantity of
50-iodotriazole did not increase proportionally (Table 1, entry 10).
When 1.5 equivalent of ICI was used as an electrophile in the pres-
ence of 10 equivalents of CuI and Et3N, the yield of 50-iodotriazole
increased dramatically (Table 1 and 11–18 entries).
a
b
c
After purification by column chromatography.
Ratios: azide/alkyne/base (Ph3P)/CuI – 1.0/2.0/2.0/0.1.
Ratios: azide/alkyne/base (Et3N)/CuI – 1.0/ 2.0/2.0/0.1.
Ratios: azide/alkyne/base (Et3N)/CuI – 1.0/2.0/2.0/1.0.
d
e
Ratios: azide/alkyne/base (Et3N)/nucleophile (ICl)/CuI – 1.0/2.0/2.0/1.5/1.0.
The structures of the new synthetized compounds (1–11) were
confirmed by 1H and 13C NMR measurements. In the 1H NMR spec-
tra of the 17b-triazoles (10a,b and 11a,b), the signals of 17-H were
seen as triplets at around 4.7 ppm, but in the cases of 10c,d and
11c,d the corresponding signals were present at lower chemical
shift (4.5 ppm), indicating the difference in the 40 substituent. In
the spectra of the 17a compounds (8 and 9), the signal of 17-H
was a doublet or a double doublet and followed the same order
as mentioned above. All the 13C NMR spectra revealed the C-17 sig-
nal at around 70 ppm, but with great differences in the spectra of
the 50-iodo (9 and 11: C-50 at around 80 ppm) or 50-H (8 and 10:
C-50at around 120 ppm) derivatives as concerns the chemical shift
of C-50. This downfield shift of C-50 clearly indicates the presence of
iodine on the triazole ring.
The optical rotations of the compounds, measured in CHCl3,
presented a characteristic picture. The [a] a com-
20 values of the 17
D
pounds (3 and 8a-d) were between +14 and +32, while those of the
compounds bearing iodine on position 50 (9a-c) were between
+106 and +153. For the 17b compounds (5 and 10a–d), the values
were between +17 and +42, while for the iodine-bearing com-
pounds, the corresponding values were less negative: between
-71 and ꢀ85 for 11a–d.
Fig. 1. Molecular structure of 9b in a 30% probability anisotropic displacement plot
with atomic labeling of non-H atoms.
752
753
3.2. Determination of the antiproliferative properties of the newly
synthetized azides (3 and 5) and triazoles (8–11)
Table 2
Non-classical
C
–
Hꢂ ꢂ ꢂX (O,I)-type intermolecular short contacts in the crystal
structure of 9b. Standard uncertainties are given only for the non-H parameters.
754
755
756
757
758
759
760
761
762
We recently reported the synthesis and CuAAC reactions of ster-
oidal azidoalcohols with terminal alkynes [19–21]. The 1,2,
3-triazoles were evaluated for their in vitro antiproliferative activ-
ities against human adherent cancer cell lines. Some derivatives
exhibited substantial activities on the proliferation of the cells,
comparable to those of the reference agent cisplatin. In view of
these results, the aim of our present study included the testing of
the newly synthetized 17-triazoles (8–11) of estrone-3-methyl
ether and their precursors (3 and 5) on a panel of human adherent
Donor – Hꢂ ꢂ ꢂacceptor
C700 –H7B0ꢂ ꢂ ꢂO1[x,y,1+z]
D – H (Å) Hꢂ ꢂ ꢂA (Å) Dꢂ ꢂ ꢂA (Å)
D - Hꢂ ꢂ ꢂA (°)
3.395 (16) 170
3.947 (10) 163
0.96
2.45
3.02
C700 –H7C0ꢂ ꢂ ꢂI10[1ꢀx,1/2+y,1ꢀz] 0.96
696
697
698
alkyne-azide cycloadditions in the presence of DMAP, Dzyuba et al.
observed the formation of ca. 20% of 5-iodo-1,4-triazole [31]. Such
compounds are considered to be produced from the trapping of a
Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018

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G. Schneider et al. / Steroids xxx (2015) xxx–xxx
9
Fig. 2. Characteristic short contacts in the 9b crystal, indicated by broken lines, as printed from program Mercury. For the sake of clarity, only three relevant H atoms are
shown.
Table 3
Experimentally determined growth inhibitory data for the synthetized azides (3 and 5) and triazoles (8–11).
Comp.
Concn. (
lM)
Growth inhibition (%) SEM
HeLa
A2780
MCF-7
MDA-MB-231
MDA-MB-361
T47D
*
3
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
10
30
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
23.7 1.8
–
–
–
21.8 1.6
–
43.9 2.1
–
52.5 3.0
–
35.3 1.8
–
39.7 2.00
–
–
25.7 2.9
33.9 1.3
–
21.3 2.2
56.6 2.9
57.4 1.0
–
20.3 2.7
–
33.1 1.7
20.5 2.5
48.5 1.2
–
5
37.1 2.0
38.2 2.3
–
–
–
–
–
28.1 2.8
25.1 1.4
25.5 1.2
–
20.5 2.6
–
–
–
22.3 1. 7
–
–
26.5 2.8
30.2 2.0
–
–
–
28.8 1.3
–
25.9 2.7
–
28.5 0.9
20.9 0.8
32.5 2.2
28.9 2.1
38.3 2.0
–
–
–
8a
–
26.0 1.3
–
47.5 1.4
–
39. 6 1.4
39.7 2.4
51.2 1.3
–
8b
35.8 1.5
–
38.8 0.9
21.7 1.7
48.1 1.1
–
22.9 1.7
–
–
38.0 1.5
38.7 0.9
40.1 1.8
41.2 1.1
42.0 0.5
39.4 1.1
38.5 1.7
51.3 1.8
–
43.6 1.5
–
59.0 2.0
–
37.1 0.8
–
25.9 2.9
–
20.0 1.2
–
21.0 1.2
–
–
–
–
–
8c
8d
9a
–
–
–
9b
–
9c
31.4 1.9
31.9 1.4
–
26.7 2.2
45.3 1.3
47.8 1.8
–
39.4 2.0
47.4 1.2
33.8 2.3
36.0 1.9
52.6 2.6
57.8 1.5
26.2 2.0
37.8 0.7
–
45.4 1.0
32.8 2.6
57.3 0.9
–
9d
–
10a
10b
10c
10d
11a
11b
11c
11d
Cisplatin
23.3 1.5
26.1 1.8
–
26.1 1.3
–
–
–
–
–
–
26.4 1.5
35.9 2.4
–
23.8 2.0
–
–
–
28.2 1.7
–
32.3 2.2
–
35.4 1.3
–
22.7 0.9
23.0 2.0
32.7 2.5
34.9 1.4
39.9 0.8
–
22.9 1.3
–
–
–
20.9 0.4
20.8 2.9
62.1 0.8
–
–
–
–
–
27.3 0.8
60.1 0.6
29.5 1.7
39.6 1.9
–
41.1 2.7
63.6 1.3
–
25.2 1.3
–
24.8 2.8
67.5 1.0
87.7 1.1
34.3 1.2
50.7 1.9
–
–
–
–
–
–
_
42.6 2.3
99.9 0.3
53.0 2.3
86.9 1.2
66.9 1.8
96.8 0.4
20.8 0.8
71.7 1.2
51.0 2.0
57.9 1.4
*
Growth inhibitory values lower than 20% are considered not substantial and are therefore not given in the table.
Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018

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3 March 2015
10
G. Schneider et al. / Steroids xxx (2015) xxx–xxx
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ˇ
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´
´
´
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action among the presented agents. The presence of iodine did
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activities of these estranetriazoles less than those of cisplatin, it is
evident that these compounds are not potential lead molecules for
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Financial support from the Hungarian Scientific Research Fund
(OTKA K101659 and K-109293) is gratefully acknowledged. This
study was supported by the European Union and co-financed by
the European Social Fund; Project Numbers: TÁMOP-4.2.A-11/1/K
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Please cite this article in press as: Schneider G et al. Synthesis of novel 17-(50-iodo)triazolyl-3-methoxyestrane epimers via Cu(I)-catalyzed azide-alkyne
cycloaddition, and an evaluation of their cytotoxic activity in vitro. Steroids (2015), http://dx.doi.org/10.1016/j.steroids.2015.02.018