Synthesis of novel steroidal 17α-triazolyl derivatives via Cu(I)-catalyzed azide-alkyne cycloaddition, and an evaluation of their cytotoxic activity in vitro

Article abstract of DOI:10.1016/j.steroids.2011.05.002

Regioselective Cu(I)-catalyzed 1,3-dipolar cycloaddition of steroidal 17α-azides with different terminal alkynes afforded novel 1,4-disubstituted triazolyl derivatives in good yields in both the estrone and the androstane series. The antiproliferative activities of the structurally related triazoles were determined in vitro on three malignant human cell lines (HeLa, MCF7 and A431), with the microculture tetrazolium assay.

Full text of DOI:10.1016/j.steroids.2011.05.002

Steroids 76 (2011) 1141–1148
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Steroids
journal homepage: www.elsevier.com/locate/steroids
Synthesis of novel steroidal 17␣-triazolyl derivatives via Cu(I)-catalyzed
azide-alkyne cycloaddition, and an evaluation of their cytotoxic activity in vitro
Éva Franka,∗, Judit Molnárb, István Zupkób, Zalán Kádára, János Wölflinga
a Department of Organic Chemistry, University of Szeged, Dóm tér 8., H-6720 Szeged, Hungary
b Department of Pharmacodynamics and Biopharmacy, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary
a r t i c l e i n f o
a b s t r a c t
Article history:
Regioselective Cu(I)-catalyzed 1,3-dipolar cycloaddition of steroidal 17␣-azides with different terminal
alkynes afforded novel 1,4-disubstituted triazolyl derivatives in good yields in both the estrone and the
androstane series. The antiproliferative activities of the structurally related triazoles were determined
in vitro on three malignant human cell lines (HeLa, MCF7 and A431), with the microculture tetrazolium
assay.
Received 1 February 2011
Received in revised form 28 March 2011
Accepted 1 May 2011
Available online 10 May 2011
© 2011 Elsevier Inc. All rights reserved.
Keywords:
Regioselectivity
Cycloaddition
Triazoles
Cytotoxic activity
1. Introduction
To the best of our knowledge, relatively few examples are to be
found in the literature in which Huisgen 1,3-dipolar cycloaddition
In recent years, considerable interest has been focused on
steroidal heterocycles in view of the broad spectrum of their
biological activities. Several novel synthesized compounds have
is applied to steroid azides [11,17], though it provides convenient
facilities for the construction of triazoles in which the hetero ring
is attached to the steroid nucleus through a nitrogen atom. Ban-
day and co-workers recently reported the syntheses of 21-triazolyl
derivatives of pregnenolone as potential anticancer agents through
use of the ‘click’ chemistry approach [18], but without any pro-
posal concerning their mode of action. Since some steroid-type
compounds are known to exert hormone receptor-independent
antiproliferative activity by the inhibition of angiogenesis, tubu-
lin polymerization, and the upregulation of apoptotic pathways
[19–21], we set out to prepare novel steroidal 17␣-triazoles via
CuAAC, untinged by the structural features necessary for effective
binding to the hormone receptors [22,23]. Although determination
of the affinities to the hormonal receptors did not fall within the
scope of the present work, in the absence of a hydroxy or keto func-
tional group at position 3, the newly prepared triazolyl derivatives
are considered to have no estrogenic or androgenic effects. Nev-
ertheless, all compounds were screened in vitro for their activities
against a panel of three human cancer cell lines (HeLa, MCF7 and
A431).
been described as potent inhibitors of 17␣-hydroxylase-C17,20
-
lyase (P45017␣) which can block androgen synthesis at an early
stage, and may therefore be useful in the treatment of prostatic
carcinoma [1–3]. Moreover, some steroidal heterocycles have also
been found to exert inhibitory effects on 5␣-reductases [4] and to
display considerable cytotoxic activity [5]. Although a number of
diverse triazolyl derivatives have been reported to exhibit biologi-
cal activity, including antibacterial [6], antiallergic [7] and anti-HIV
[8] effects, steroids containing this kind of structural moiety have
received less attention from both synthetic and pharmacological
aspects [9,10].
Since the first reports [11,12], Cu-catalyzed azide-alkyne 1,3-
dipolar cycloaddition (CuAAC) has found numerous applications
across a wide variety of disciplines, including polymer chemistry,
materials research and pharmaceutical sciences, as evidenced by
a huge number of related articles and several reviews [13–15].
The certain advantageous properties (versatility, regiospecific reac-
tions, the lack of by-products and high conversions) have made
‘click’ chemistry [16] an ideal tool for the synthesis of libraries for
initial screening and for structure–activity profiling.
2. Experimental
2.1. General
∗
Melting points (Mps) were determined on a Kofler block and
are uncorrected. EI mass spectra were recorded with a Varian MAT
Corresponding author. Fax: +36 62 544199.
E-mail address: frank@chem.u-szeged.hu (É. Frank).
0039-128X/$ – see front matter © 2011 Elsevier Inc. All rights reserved.
doi:10.1016/j.steroids.2011.05.002

1142
É. Frank et al. / Steroids 76 (2011) 1141–1148
(2C, C-2ꢀ and C-6ꢀ), 127.8 (C-1), 128.5 (2C, C-3ꢀ and C-5ꢀ), 132.8 (C-
10), 137.3 and 137.9: C-5 and C-1ꢀ, 156.7 (C-3) ppm. EI-MS (70 eV)
m/z (%): 387 [M+] (35), 91 (100).
311A spectrometer at an ionization energy of 70 eV. 1H NMR spec-
tra were obtained in CDCl3 solution (if not otherwise stated) at
500 MHz (Bruker DRX 500), and the 13C NMR spectra at 125 MHz
with the same instrument. Chemical shifts are reported relative to
TMS; J values are given in Hz. 13C NMR spectra are 1H-decoupled.
For determination of the multiplicities, the J-MOD pulse sequence
was used. Elemental analyses were carried out with a Perkin-Elmer
CHN Analyzer (Model 2400). All solvents were distilled and dried
prior to use. Reagents and materials were obtained from commer-
cial suppliers and were used without purification. The reactions
were monitored by TLC on Kieselgel-G (Merck Si 254F) layers
(0.25 mm thick); solvent systems (ss) (A) CH2Cl2/hexane (70:30,
v/v); (B) CH2Cl2/hexane (30:70, v/v); (C) CH2Cl2; (D) EtOAc/CH2Cl2
(2:98, v/v); (E) EtOAc/CH2Cl2 (5:95, v/v). The spots were detected
by spraying with 5% phosphomolybdic acid in 50% aqueous H3PO4.
The Rf values were determined for spots observed by illumination
at 254 and 365 nm. Flash chromatography: silica gel 60, 40–63 ␮m.
2.4. General procedure for the synthesis of triazoles (10a–j and
11a–j)
3-Benzyloxyestra-1,3,5(10)-triene-17␣-azide
7
(388 mg,
1.00 mmol) or 5␣-androst-2-ene-17␣-azide 8 (299 mg, 1.00 mmol)
was dissolved in CH2Cl2 (20 mL), and CuI (19.0 mg, 0.10 mmol),
triphenylphosphine (52 mg, 0.20 mmol) and substituted acetylene
derivative (9a–j, 1.00 mmol) were added. The mixture was stirred
under reflux for 24 h, and then diluted with water (20 mL) and
extracted with CH2Cl2 (2× 20 mL). The combined organic phases
were dried over Na2SO4, and evaporated in vacuo. The crude prod-
uct was purified by flash chromatography, using EtOAc/CH2Cl2
(2:98, v/v) as eluent.
2.2. Synthesis of 17ˇ-estradiol-3-benzyl ether 17-tosylate (5)
2.4.1. Synthesis of 3-benzyloxy-17˛-[4-phenyl-1H-1,2,3-triazol-
1-yl]estra-1,3,5(10)-triene
17␤-Estradiol-3-benzyl ether 3 (11.0 g, 30.3 mmol) was dis-
solved in pyridine (100 mL) and para-toluenesulfonyl chloride
(12.0 g, 62.9 mmol) was added portionwise. The mixture was
stirred for 72 h at room temperature, then poured onto a mix-
ture of ice and concentrated H2SO4 (80 mL). The precipitate that
formed was filtered off, washed until neutral with water and
dried. The crude product was purified by flash chromatography
(CH2Cl2/hexane = 50:50, v/v) to give 5 (14.9 g, 95%) as a white solid.
Mp 115–117 ◦C; Rf = 0.34 (ss A). Anal. Calcd. for C32H36O4S: C, 74.39;
H, 7.02. Found: C, 74.52; H, 7.11. 1H NMR (500 MHz, CDCl3): ı = 0.84
(s, 3H, 18-H3), 1.14 (m, 2H), 1.31 (m, 1H), 1.41 (m, 3H), 1.58–1.85
(overlapping m, 4H), 1.99 (m, 1H), 2.14 (m, 1H), 2.23 (m, 1H), 2.47
(s, 3H, 4ꢀꢀ-H3), 2.82 (m, 2H, 6-H2), 4.35 (t, 1H, J = 8.6 Hz, 17-H), 5.03
(s, 2H, O-CH2), 6.71 (d, 1H, J = 2.3 Hz, 4-H), 6.78 (dd, 1H, J = 8.6 Hz,
J = 2.3 Hz, 2-H), 7.16 (d, 1H, J = 8.6 Hz, 1-H), 7.30–7.43 (overlapping
m, 7H, 2ꢀ-H, 3ꢀ-H, 4ꢀ-H, 5ꢀ-H, 6ꢀ-H, 3ꢀꢀ-H and 5ꢀꢀ-H), 7.81 (d, 2H,
J = 8.2 Hz, 2ꢀꢀ-H and 6ꢀꢀ-H) ppm. 13C NMR (125 MHz, CDCl3): ı = 11.7
(C-18), 21.6 (4ꢀꢀ-CH3), 23.0 (CH2), 25.9 (CH2), 27.0 (CH2), 29.7 (CH2),
29.6 (CH2), 36.0 (CH2), 38.4 (CH), 43.3 (C-13), 43.6 (CH), 49.0 (CH),
69.9 (O-CH2), 89.8 (C-17), 112.3 (C-2), 114.8 (C-4), 126.3 (C-4ꢀ),
127.4 (2C, C-2ꢀ and C-6ꢀ), 127.8 (3C, C-4ꢀ, C-2ꢀꢀ and C-6ꢀꢀ), 128.5 (2C,
C-3ꢀ and C-5ꢀ), 129.7 (2C, C-3ꢀꢀ and C-5ꢀꢀ), 132.4 (C-10), 134.2 (C-1ꢀꢀ),
137.2 and 138.0: C-5 and C-1ꢀ, 144.4 (C-4ꢀꢀ), 156.6 (C-3) ppm. EI-MS
(70 eV) m/z (%): 516 [M+] (26), 91 (100).
(10a)
Compound 7 and phenylacetylene (9a, 0.11 mL) were used for
the synthesis as described in Section 2.4. After purification, 10a was
obtained as a white solid (416 mg). Mp 169–171 ◦C; Rf = 0.52 (ss D).
Anal. Calcd. for C33H35N3O: C, 80.95; H, 7.20. Found: C, 81.13; H,
7.12. 1H NMR (500 MHz, CDCl3): ı = 0.56 (m, 1H), 1.01 (s, 3H, 18-
H3), 1.27 (m, 1H), 1.43–1.63 (overlapping m, 4H), 1.85 (m, 1H), 1.98
(m, 1H), 2.09 (m, 1H), 2.20 (m, 2H), 2.40 (m, 1H), 2.59 (m, 1H),
2.87 (m, 2H, 6-H2), 4.69 (dd, 1H, J = 8.2 Hz, J = 1.0 Hz, 17-H), 5.02
(s, 2H, Bn-CH2), 6.73 (d, 1H, J = 2.3 Hz, 4-H), 6.75 (dd, 1H, J = 8.5 Hz,
J = 2.3 Hz, 2-H), 7.10 (d, 1H, J = 8.5 Hz, 1-H), 7.30–7.46 (overlapping
m, 8H, 2ꢀ-H, 3ꢀ-H, 4ꢀ-H, 5ꢀ-H, 6ꢀ-H, 3ꢀꢀꢀ-H, 4ꢀꢀꢀ-H and 5ꢀꢀꢀ-H), 7.73 (s,
1H, 5ꢀꢀ-H), 7.88 (d, 2H, J = 7.3 Hz, 2ꢀꢀꢀ-H and 6ꢀꢀꢀ-H) ppm. 13C NMR
(125 MHz, CDCl3): ı = 18.7 (C-18), 24.9 (CH2), 25.9 (CH2), 27.9 (CH2),
28.7 (CH2), 29.8 (CH2), 32.6 (CH2), 39.1 (CH), 43.1 (CH), 46.6 (C-13),
48.8 (CH), 69.9 (Bn-CH2), 70.4 (C-17), 112.2 (C-2), 114.4 (C-4), 119.9
(C-5ꢀꢀ), 125.6 (2C, C-2ꢀꢀꢀ and C-6ꢀꢀꢀ), 126.2 (C-1), 127.4 (2C, C-2ꢀ and
C-6ꢀ), 127.8 (C-4ꢀ), 128.0 (C-4ꢀꢀꢀ), 128.5 (2C, C3ꢀ and C-5ꢀ), 128.8 (2C,
C-3ꢀꢀꢀ and C-5ꢀꢀꢀ), 130.7 (C-1ꢀꢀꢀ), 132.5 (C-10), 137.2 (C-5), 137.8 (C-
1ꢀ), 146.9 (C-4ꢀꢀ), 156.7 (C-3) ppm. EI-MS (70 eV) m/z (%): 489 [M+]
(51), 91 (100).
2.4.2. Synthesis of 3-benzyloxy-17˛-[4-(4-methoxyphenyl)-1H-
1,2,3-triazol-1-yl]estra-1,3,5(10)-triene
2.3. Synthesis of 3-benzyloxyestra-1,3,5(10)-triene-17˛-azide (7)
(10b)
Compound 7 and 4-methoxyphenylacetylene (9b, 132 mg) were
used for the synthesis as described in Section 2.4. After purifica-
tion, 10b was obtained as a white solid (437 mg). Mp 187–189 ◦C;
Rf = 0.45 (ss E). Anal. Calcd. for C34H37N3O2: C, 78.58; H, 7.18. Found:
C, 78.70; H, 7.32. 1H NMR (500 MHz, CDCl3): ı = 0.57 (m, 1H), 1.00
(s, 3H, 18-H3), 1.42–1.62 (overlapping m, 5H), 1.86 (m, 1H), 1.98 (m,
1H), 2.10 (m, 1H), 2.19 (m, 2H), 2.39 (m, 1H), 2.58 (m, 1H), 2.86 (m,
2H, 6-H2), 3.85 (s, 3H, 4ꢀꢀꢀ-OMe), 4.67 (dd, 1H, J = 8.3 Hz, J = 1.1 Hz,
17-H), 5.02 (s, 2H, Bn-CH2), 6.72 (d, 1H, J = 2.3 Hz, 4-H), 6.74 (dd,
1H, J = 8.6 Hz, J = 2.3 Hz, 2-H), 6.97 (d, 2H, J = 8.7 Hz, 3ꢀꢀꢀ-H and 5ꢀꢀꢀ-H),
7.01 (d, 1H, J = 8.6 Hz, 1-H), 7.31 (m, 1H, 4ꢀ-H), 7.37 (m, 2H, 3ꢀ-H and
5ꢀ-H), 7.42 (d, 2H, J = 7.3 Hz, 2ꢀ-H and 6ꢀ-H), 7.63 (s, 1H, 5ꢀꢀ-H), 7.80
(d, 2H, J = 8.7 Hz, 2ꢀꢀꢀ-H and 6ꢀꢀꢀ-H) ppm. 13C NMR (125 MHz, CDCl3):
ı = 18.7 (C-18), 24.9 (CH2), 26.0 (CH2), 27.9 (CH2), 28.7 (CH2), 29.8
(CH2), 32.7 (CH2), 39.2 (CH), 43.1 (CH), 46.6 (C-13), 48.9 (CH), 55.3
(4ꢀꢀꢀ-OMe), 69.9 (Bn-CH2), 70.4 (C-17), 112.3 (C-2), 114.2 (2C, C-3ꢀꢀꢀ
and C-5ꢀꢀꢀ), 114.8 (C-4), 119.1 (C-5ꢀꢀ), 123.6 (C-1ꢀꢀꢀ), 126.2 (C-1), 126.9
(2C, C-2ꢀꢀꢀ and C-6ꢀꢀꢀ), 127.4 (2C, C-2ꢀ and C-6ꢀ), 127.8 (C-4ꢀ), 128.5
(2C, C3ꢀ and C-5ꢀ), 132.6 (C-10), 137.3 (C-5), 137.8 (C-1ꢀ), 146.8 (C-
Compound
5 (5.4 g, 10.5 mmol) was dissolved in N,N-
dimethylformamide (80 mL) and NaN3 (5.4 g, 83.1 mmol) was
added. The mixture was stirred for 48 h at 100 ◦C, and then poured
into water (50 mL) and extracted with CH2Cl2 (3× 50 mL). The com-
bined organic phases were dried with Na2SO4 and concentrated in
vacuo. The crude product was purified by flash chromatography
(CH2Cl2/hexane = 20:80, v/v) to give 7 (3.3 g, 82%) as a white solid.
Mp 78–79 ◦C; Rf = 0.34 (ss B). Anal. Calcd. for C25H29N3O: C, 77.48;
H, 7.54. Found: C, 77.34; H, 7.65. 1H NMR (500 MHz, CDCl3): ı = 0.79
(s, 3H, 18-H3), 1.28–1.57 (overlapping m, 6H), 1.69–1.92 (overlap-
ping m, 4H), 2.23 (m, 2H), 2.37 (m, 1H), 2.86 (m, 2H, 6-H2), 3.60 (d,
1H, J = 6.4 Hz, 17-H), 5.04 (s, 2H, O-CH2), 6.74 (d, 1H, J = 2.1 Hz, 4-H),
6.79 (dd, 1H, J = 8.6 Hz, J = 2.1 Hz, 2-H), 7.23 (d, 1H, J = 8.6 Hz, 1-H),
7.33 (t-like m, 1H, 4ꢀ-H), 7.39 (t-like m, 2H, 3ꢀ-H and 5ꢀ-H), 7.44
(d, 2H, J = 7.2 Hz, 2ꢀ-H and 6ꢀ-H) ppm. 13C NMR (125 MHz, CDCl3):
ı = 17.7 (C-18), 24.3 (CH2), 26.2 (CH2), 28.0 (CH2), 28.7 (CH2), 29.8
(CH2), 32.6 (CH2), 39.0 (CH), 43.4 (CH), 46.0 (C-13), 48.5 (CH), 69.9
(O-CH2), 71.5 (C-17), 112.2 (C-2), 114.8 (C-4), 126.4 (C-4ꢀ), 127.4

É. Frank et al. / Steroids 76 (2011) 1141–1148
1143
4ꢀꢀ), 156.8 (C-3), 159.5 (C-4ꢀꢀꢀ) ppm. EI-MS (70 eV) m/z (%): 519 [M+]
(17), 491 (20), 91 (100).
119.6 (C-5ꢀꢀ), 125.7 (2C, C-3ꢀꢀꢀ and C-5ꢀꢀꢀ), 126.2 (C-1), 127.4 (2C, C-
2ꢀ and C-6ꢀ), 127.8 (C-4ꢀ), 128.2 (C-1ꢀꢀꢀ), 128.3 (2C, C-2ꢀꢀꢀ and C-6ꢀꢀꢀ),
128.5 (2C, C3ꢀ and C-5ꢀ), 132.6 (C-10), 137.3 (C-5), 137.8 (C-1ꢀ), 144.2
(C-4ꢀꢀꢀ), 147.0 (C-4ꢀꢀ), 156.8 (C-3) ppm. EI-MS (70 eV) m/z (%): 517
[M+] (25), 91 (100).
2.4.3. Synthesis of 3-benzyloxy-17˛-[4-(4-fluorophenyl)-1H-
1,2,3-triazol-1-yl]estra-1,3,5(10)-triene
(10c)
Compound 7 and 4-fluorophenylacetylene (9c, 0.11 mL) were
used for the synthesis as described in Section 2.4. After purifica-
tion, 10c was obtained as a white solid (431 mg). Mp 189–192 ◦C;
Rf = 0.17 (ss C). Anal. Calcd. for C33H34FN3O: C, 78.08; H, 6.75. Found:
C, 78.19; H, 6.92. 1H NMR (500 MHz, CDCl3): ı = 0.57 (m, 1H), 1.01
(s, 3H, 18-H3), 1.43–1.62 (overlapping m, 5H), 1.86 (m, 1H), 1.98
(m, 1H), 2.10 (m, 1H), 2.19 (m, 2H), 2.39 (m, 1H), 2.59 (m, 1H),
2.87 (m, 2H, 6-H2), 4.68 (dd, 1H, J = 8.3 Hz, J = 1.2 Hz, 17-H), 5.02
(s, 2H, Bn-CH2), 6.72 (d, 1H, J = 2.3 Hz, 4-H), 6.75 (dd, 1H, J = 8.6 Hz,
J = 2.3 Hz, 2-H), 7.10 (d, 1H, J = 8.6 Hz, 1-H), 7.12 (dd, 2H, J = 15.6 Hz,
J = 8.5 Hz, 3ꢀꢀꢀ-H and 5ꢀꢀꢀ-H), 7.31 (m, 1H, 4ꢀ-H), 7.37 (m, 2H, 3ꢀ-H
and 5ꢀ-H), 7.42 (d, 2H, J = 7.1 Hz, 2ꢀ-H and 6ꢀ-H), 7.68 (s, 1H, 5ꢀꢀ-H),
7.84 (dd, 2H, J = 8.5 Hz, J = 5.4 Hz, 2ꢀꢀꢀ-H and 6ꢀꢀꢀ-H) ppm. 13C NMR
(125 MHz, CDCl3): ı = 18.7 (C-18), 24.9 (CH2), 25.9 (CH2), 27.9 (CH2),
28.7 (CH2), 29.8 (CH2), 32.7 (CH2), 39.1 (CH), 43.1 (CH), 46.6 (C-13),
48.9 (CH), 69.9 (Bn-CH2), 70.5 (C-17), 112.3 (C-2), 114.8 (C-4), 115.7
(d, 2C, J = 21.7 Hz, C-3ꢀꢀꢀ and C-5ꢀꢀꢀ), 119.6 (C-5ꢀꢀ), 126.2 (C-1), 127.0
(C-1ꢀꢀꢀ), 127.3 (d, 2C, J = 7.7 Hz, C-2ꢀꢀꢀ and C-6ꢀꢀꢀ), 127.4 (2C, C-2ꢀ and
C-6ꢀ), 127.8 (C-4ꢀ), 128.5 (2C, C3ꢀ and C-5ꢀ), 132.5 (C-10), 137.3 (C-5),
2.4.6. Synthesis of 3-benzyloxy-17˛-[4-(4-propylphenyl)-1H-
1,2,3-triazol-1-yl]estra-1,3,5(10)-triene
(10f)
Compound 7 and 4-propylphenylacetylene (9f, 0.16 mL) were
used for the synthesis as described in Section 2.4. After purifica-
tion, 10f was obtained as a white solid (463 mg). Mp 136–138 ◦C;
Rf = 0.34 (ss D). Anal. Calcd. for C36H41N3O: C, 81.32; H, 7.77. Found:
C, 81.46; H, 7.64. 1H NMR (500 MHz, CDCl3): ı = 0.54 (m, 1H),
0.96 (t, 3H, J = 7.0 Hz, 4ꢀꢀ-CH2CH2CH3), 1.00 (s, 3H, 18-H3), 1.28 (m,
1H), 1.47–1.69 (overlapping m, 6H), 1.84 (m, 1H), 1.97 (m, 1H),
2.08 (m, 1H), 2.19 (m, 2H), 2.42 (m, 1H), 2.58 (m, 1H), 2.61 (t,
2H, J = 7.0 Hz, 4ꢀꢀ-CH2CH2CH3), 2.86 (m, 2H, 6-H2), 4.72 (dd, 1H,
J = 8.3 Hz, J = 1.2 Hz, 17-H), 5.02 (s, 2H, Bn-CH2), 6.71 (d, 1H, J = 2.3 Hz,
4-H), 6.74 (dd, 1H, J = 8.6 Hz, J = 2.3 Hz, 2-H), 7.10 (d, 1H, J = 8.6 Hz,
1-H), 7.26 (d, 2H, J = 8.1 Hz, 3ꢀꢀꢀ-H and 5ꢀꢀꢀ-H), 7.31 (m, 1H, 4ꢀ-H),
7.37 (m, 2H, 3ꢀ-H and 5ꢀ-H), 7.42 (d, 2H, J = 7.1 Hz, 2ꢀ-H and 6ꢀ-H),
7.68 (s, 1H, 5ꢀꢀ-H), 7.85 (d, 2H, J = 8.1 Hz, 2ꢀꢀꢀ-H and 6ꢀꢀꢀ-H) ppm. 13
C
NMR (125 MHz, CDCl3): ı = 13.7 (4ꢀꢀꢀ-CH2CH2CH3), 18.7 (C-18), 24.4
(CH2), 24.9 (CH2), 25.9 (CH2), 27.9 (CH2), 28.7 (CH2), 29.8 (CH2), 32.7
(CH2), 37.8 (CH2), 39.1 (CH), 43.1 (CH), 46.5 (C-13), 48.9 (CH), 69.9
(Bn-CH2), 70.7 (C-17), 112.3 (C-2), 114.8 (C-4), 119.3 (C-5ꢀꢀ), 125.5
(2C, C-2ꢀꢀꢀ and C-6ꢀꢀꢀ), 126.2 (C-1), 127.4 (2C, C-2ꢀ and C-6ꢀ), 127.8
(C-4ꢀ), 128.2 (C-1ꢀꢀꢀ), 128.5 (2C, C-3ꢀꢀꢀ and C-5ꢀꢀꢀ), 129.0 (2C, C3ꢀ and
C-5ꢀ), 132.5 (C-10), 137.3 (C-5), 137.8 (C-1ꢀ), 142.8 (C-4ꢀꢀꢀ), 147.0
(C-4ꢀꢀ), 156.8 (C-3) ppm. EI-MS (70 eV) m/z (%): 531 [M+] (22), 91
(100).
137.8 (C-1ꢀ), 146.1 (C-4ꢀꢀ), 156.8 (C-3), 162.6 (d, J = 247.3 Hz, C-4ꢀꢀꢀ
ppm. EI-MS (70 eV) m/z (%): 507 [M+] (32), 254 (12), 91 (100).
)
2.4.4. Synthesis of 3-benzyloxy-17˛-[4-(4-tolyl)-1H-1,2,3-
triazol-1-yl]estra-1,3,5(10)-triene
(10d)
Compound 7 and 4-tolylacetylene (9d, 0.12 mL) were used for
the synthesis as described in Section 2.4. After purification, 10d was
obtained as a white solid (428 mg). Mp 216–218 ◦C; Rf = 0.54 (ss D).
Anal. Calcd. for C34H37N3O: C, 81.08; H, 7.40. Found: C, 81.17; H,
7.23. 1H NMR (500 MHz, CDCl3): ı = 0.55 (m, 1H), 1.00 (s, 3H, 18-
H3), 1.27 (m, 1H), 1.43–1.54 (overlapping m, 4H), 1.85 (m, 1H), 1.97
(m, 1H), 2.09 (m, 1H), 2.18 (m, 2H), 2.38 (s, 3H, 4ꢀꢀꢀ-H3), 2.39 (m, 1H),
2.59 (m, 1H), 2.86 (m, 2H, 6-H2), 4.68 (dd, 1H, J = 8.3 Hz, J = 1.2 Hz,
17-H), 5.01 (s, 2H, Bn-CH2), 6.72 (d, 1H, J = 2.3 Hz, 4-H), 6.74 (dd,
1H, J = 8.6 Hz, J = 2.3 Hz, 2-H), 7.01 (d, 1H, J = 8.6 Hz, 1-H), 7.24 (d,
2H, J = 8.0 Hz, 3ꢀꢀꢀ-H and 5ꢀꢀꢀ-H), 7.31 (m, 1H, 4ꢀ-H), 7.37 (m, 2H, 3ꢀ-H
and 5ꢀ-H), 7.41 (d, 2H, J = 7.1 Hz, 2ꢀ-H and 6ꢀ-H), 7.67 (s, 1H, 5ꢀꢀ-H),
7.75 (d, 2H, J = 8.0 Hz, 2ꢀꢀꢀ-H and 6ꢀꢀꢀ-H) ppm. EI-MS (70 eV) m/z (%):
503 [M+] (23), 91 (100).
2.4.7. Synthesis of 3-benzyloxy-17˛-[4-(4-tert-butylphenyl)-1H-
1,2,3-triazol-1-yl]estra-1,3,5(10)-triene
(10g)
Compound 7 and 4-tert-butylphenylacetylene (9g, 0.18 mL)
were used for the synthesis as described in Section 2.4. After purifi-
cation, 10g was obtained as a white solid (458 mg). Mp 157–159 ◦C;
Rf = 0.40 (ss D). Anal. Calcd. for C37H43N3O: C, 81.43; H, 7.94. Found:
C, 81.60; H, 8.07. 1H NMR (500 MHz, CDCl3): ı = 0.53 (m, 1H), 1.01
(s, 3H, 18-H3), 1.34 (s, 9H, 3 × tBu-CH3), 1.45–1.61 (overlapping m,
5H), 1.84 (m, 1H), 1.98 (m, 1H), 2.08 (m, 1H), 2.19 (m, 2H), 2.45
(m, 1H), 2.63 (m, 1H), 2.86 (m, 2H, 6-H2), 4.75 (bs, 1H, 17-H), 5.02
(s, 2H, Bn-CH2), 6.71 (d, 1H, J = 2.3 Hz, 4-H), 6.74 (dd, 1H, J = 8.5 Hz,
J = 2.3 Hz, 2-H), 7.10 (d, 1H, J = 8.5 Hz, 1-H), 7.31 (m, 1H, 4ꢀ-H), 7.37
(m, 2H, 3ꢀ-H and 5ꢀ-H), 7.42 (d, 2H, J = 7.1 Hz, 2ꢀ-H and 6ꢀ-H), 7.49
(d, 2H, J = 8.1 Hz, 3ꢀꢀꢀ-H and 5ꢀꢀꢀ-H), 7.68 (s, 1H, 5ꢀꢀ-H), 7.91 (d, 2H,
J = 8.1 Hz, 2ꢀꢀꢀ-H and 6ꢀꢀꢀ-H) ppm. 13C NMR (125 MHz, CDCl3): ı = 18.7
(C-18), 24.9 (CH2), 25.9 (CH2), 27.9 (CH2), 28.8 (CH2), 29.8 (CH2),
31.2 (3C, 3 × tBu-CH3), 32.7 (CH2), 34.7 (4ꢀꢀꢀ-tBu-C), 39.1 (CH), 43.1
(CH), 46.5 (C-13), 48.9 (CH), 69.9 (Bn-CH2), 70.2 (C-17), 112.3 (C-2),
114.8 (C-4), 119.5 (C-5ꢀꢀ), 125.3 (2C, C-3ꢀꢀꢀ and C-5ꢀꢀꢀ), 125.7 (2C, C-2ꢀꢀꢀ
and C-6ꢀꢀꢀ), 126.2 (C-1), 127.4 (2C, C-2ꢀ and C-6ꢀ), 127.8 (C-4ꢀ), 128.1
(C-1ꢀꢀꢀ), 128.5 (2C, C3ꢀ and C-5ꢀ), 132.5 (C-10), 137.3 (C-5), 137.8 (C-
1ꢀ), 147.0 (C-4ꢀꢀ), 151.3 (C-4ꢀꢀꢀ), 156.8 (C-3) ppm. EI-MS (70 eV) m/z
(%): 545 [M+] (17), 91 (100).
2.4.5. Synthesis of 3-benzyloxy-17˛-[4-(4-ethylphenyl)-1H-
1,2,3-triazol-1-yl]estra-1,3,5(10)-triene
(10e)
Compound 7 and 4-ethylphenylacetylene (9e, 0.13 mL) were
used for the synthesis as described in Section 2.4. After purifica-
tion, 10e was obtained as a white solid (430 mg). Mp 149–152 ◦C;
Rf = 0.52 (ss D). Anal. Calcd. for C35H39N3O: C, 81.20; H, 7.59. Found:
C, 81.08; H, 7.67. 1H NMR (500 MHz, CDCl3): ı = 0.56 (m, 1H), 1.00
(s, 3H, 18-H3), 1.27 (t, 3H, J = 7.6 Hz, 4ꢀꢀꢀ-CH2CH3), 1.42–1.62 (over-
lapping m, 5H), 1.86 (m, 1H), 1.98 (m, 1H), 2.09 (m, 1H), 2.19 (m,
2H), 2.40 (m, 1H), 2.58 (m, 1H), 2.69 (q, 2H, J = 7.6 Hz, 4ꢀꢀꢀ-CH2CH3),
2.86 (m, 2H, 6-H2), 4.67 (dd, 1H, J = 8.3 Hz, J = 1.2 Hz, 17-H), 5.02
(s, 2H, Bn-CH2), 6.72 (d, 1H, J = 2.3 Hz, 4-H), 6.74 (dd, 1H, J = 8.6 Hz,
J = 2.3 Hz, 2-H), 7.10 (d, 1H, J = 8.6 Hz, 1-H), 7.27 (d, 2H, J = 8.1 Hz,
3ꢀꢀꢀ-H and 5ꢀꢀꢀ-H), 7.31 (m, 1H, 4ꢀ-H), 7.37 (m, 2H, 3ꢀ-H and 5ꢀ-H),
7.42 (d, 2H, J = 7.1 Hz, 2ꢀ-H and 6ꢀ-H), 7.68 (s, 1H, 5ꢀꢀ-H), 7.79 (d, 2H,
J = 8.1 Hz, 2ꢀꢀꢀ-H and 6ꢀꢀꢀ-H) ppm. 13C NMR (125 MHz, CDCl3): ı = 15.5
(4ꢀꢀꢀ-CH2CH3), 18.7 (C-18), 24.9 (CH2), 26.0 (CH2), 28.0 (CH2), 28.7
(2C, 2 × CH2), 29.8 (CH2), 32.7 (CH2), 39.2 (CH), 43.1 (CH), 46.6 (C-
13), 48.9 (CH), 69.9 (Bn-CH2), 70.4 (C-17), 112.3 (C-2), 114.8 (C-4),
2.4.8. Synthesis of 3-benzyloxy-17˛-[4-cyclopropyl-1H-1,2,3-
triazol-1-yl]estra-1,3,5(10)-triene
(10h)
Compound 7 and cyclopropylacetylene (9h, 0.09 mL) were used
for the synthesis as described in Section 2.4. After purification, 10h
was obtained as a white solid (399 mg). Mp 74–76 ◦C; Rf = 0.21 (ss
D). Anal. Calcd. for C30H35N3O: C, 79.43; H, 7.78. Found: C, 79.26;
H, 7.92. 1H NMR (500 MHz, CDCl3): ı = 0.45 (m, 1H), 0.95 (s, 3H,

1144
É. Frank et al. / Steroids 76 (2011) 1141–1148
18-H3), 0.96 (m 2H), 1.42–1.56 (overlapping m, 6H), 1.76 (m, 1H),
1.95 (m, 3H), 2.05–2.20 (overlapping m, 3H), 2.27 (m, 1H), 2.51 (m,
1H), 2.85 (m, 2H, 6-H2), 4.58 (dd, 1H, J = 8.3 Hz, J = 1.0 Hz, 17-H), 5.02
(s, 2H, Bn-CH2), 6.70 (d, 1H, J = 2.2 Hz, 4-H), 6.75 (dd, 1H, J = 8.6 Hz,
J = 2.2 Hz, 2-H), 7.11 (d, 1H, J = 8.6 Hz, 1-H), 7.19 (s, 1H, 5ꢀꢀ-H), 7.31
(m, 1H, 4ꢀ-H), 7.37 (m, 2H, 3ꢀ-H and 5ꢀ-H), 7.42 (d, 2H, J = 7.2 Hz,
2ꢀ-H and 6ꢀ-H) ppm. 13C NMR (125 MHz, CDCl3): ı = 6.7 (C-1ꢀꢀꢀ), 7.7
(2C, C-2ꢀꢀꢀ and C-3ꢀꢀꢀ), 18.6 (C-18), 24.8 (CH2), 25.9 (CH2), 27.9 (CH2),
28.6 (CH2), 29.8 (CH2), 32.5 (CH2), 39.1 (CH), 43.1 (CH), 46.4 (C-13),
48.8 (CH), 69.9 (Bn-CH2), 70.1 (C-17), 112.2 (C-2), 114.7 (C-4), 120.0
(C-5ꢀꢀ), 126.2 (C-1), 127.4 (2C, C-2ꢀ and C-6ꢀ), 127.8 (C-4ꢀ), 128.5 (2C,
C3ꢀ and C-5ꢀ), 132.5 (C-10), 137.2 (C-5), 137.8 (C-1ꢀ), 149.3 (C-4ꢀꢀ),
156.7 (C-3) ppm. EI-MS (70 eV) m/z (%): 453 [M+] (30), 91 (100).
was obtained as a white solid (329 mg). Mp 192–193 ◦C; Rf = 0.35
(ss D). Anal. Calcd. for C27H35N3: C, 80.75; H, 8.78. Found: C, 80.63;
H, 8.91. 1H NMR (500 MHz, CDCl3): ı = 0.29 (m, 1H), 0.60 (m, 1H),
0.73 (s, 3H, 19-H3), 0.96 (s, 3H, 18-H3), 1.03 (m, 1H), 1.29 (m,
1H), 1.26–1.47 (overlapping m, 7H), 1.51–1.70 (overlapping m, 3H),
1.73–1.87 (overlapping m, 3H), 2.08 (m, 1H), 2.29 (m, 1H), 2.52 (m,
1H), 4.63 (dd, 1H, J = 7.2 Hz, J = 1.2 Hz, 17-H), 5.55 (m, 2H, 2-H and
3-H), 7.32 (t-like m, 1H, 4ꢀꢀ-H), 7.42 (t-like m, 2H, 3ꢀꢀ-H and 5ꢀꢀ-
H), 7.67 (s, 1H, 5ꢀ-H), 7.86 (d-like m, 2H, 2ꢀꢀ-H and 6ꢀꢀ-H) ppm. 13
C
NMR (125 MHz, CDCl3): ı = 11.6 (C-19), 18.6 (C-18), 20.2 (CH2), 25.2
(CH2), 28.6 (2C, 2 × CH2), 30.2 (CH2), 31.9 (CH2), 32.6 (CH2), 34.6
(C-10), 35.9 (CH), 39.5 (CH2), 41.2 (CH), 46.2 (C-13), 49.9 (CH), 53.1
(CH), 70.4 (C-17), 119.7 (C-5ꢀ), 125.6 (2C, C-2ꢀꢀ and C-6ꢀꢀ), 125.7 (2C,
C-2 and C-3), 128.0 (C-4ꢀꢀ), 128.8 (2C, C-3ꢀꢀ and C-5ꢀꢀ), 130.8 (C-1ꢀꢀ),
146.8 (C-4ꢀ) ppm. EI-MS (70 eV) m/z (%): 401 [M+] (40), 372 (71),
358 (44), 145 (100), 117 (41), 93 (45), 91 (62), 79 (51), 67 (37), 55
(27).
2.4.9. Synthesis of 3-benzyloxy-17˛-[4-cyclopentyl-1H-1,2,3-
triazol-1-yl]estra-1,3,5(10)-triene
(10i)
Compound 7 and cyclopentylacetylene (9i, 0.12 mL) were used
for the synthesis as described in Section 2.4. After purification, 10i
was obtained as a white solid (385 mg). Mp 105–107 ◦C; Rf = 0.35
(ss E). Anal. Calcd. for C32H39N3O: C, 79.79; H, 8.16. Found: C,
79.95; H, 8.26. 1H NMR (500 MHz, CDCl3): ı = 0.45 (m, 1H), 0.97
(s, 3H, 18-H3), 0.40–1.57 (overlapping m, 5H), 1.69–1.87 (overlap-
ping m, 7H), 1.97 (m, 1H), 2.07–2.21 (overlapping m, 5H), 2.33
(m, 1H), 2.53 (m, 1H), 2.86 (m, 2H, 6-H2), 3.23 (m, 1H), 4.60 (d,
1H, J = 7.8 Hz, 17-H), 5.02 (s, 2H, Bn-CH2), 6.71 (d, 1H, J = 2.3 Hz, 4-
H), 6.75 (dd, 1H, J = 8.5 Hz, J = 2.3 Hz, 2-H), 7.11 (d, 1H, J = 8.5 Hz,
1-H), 7.26 (s, 1H, 5ꢀꢀ-H), 7.31 (m, 1H, 4ꢀ-H), 7.37 (m, 2H, 3ꢀ-H
and 5ꢀ-H), 7.42 (d, 2H, J = 7.2 Hz, 2ꢀ-H and 6ꢀ-H) ppm. 13C NMR
(125 MHz, CDCl3): ı = 18.7 (C-18), 24.9 (CH2), 25.1 (CH2), 25.9 (CH2),
27.9 (CH2), 28.6 (2C, 2 × CH2), 29.8 (CH2), 32.6 (CH2), 33.3 (2C,
2 × CH2), 36.5 (C-1ꢀꢀꢀ), 39.1 (CH), 43.1 (CH), 46.5 (C-13), 48.8 (CH),
69.9 (Bn-CH2), 70.5 (C-17), 112.3 (C-2), 114.8 (C-4), 120.4 (C-5ꢀꢀ),
126.2 (C-1), 127.4 (2C, C-2ꢀ and C-6ꢀ), 127.8 (C-4ꢀ), 128.5 (2C, C3ꢀ
and C-5ꢀ), 132.5 (C-10), 137.3 (C-5), 137.8 (C-1ꢀ), 151.4 (C-4ꢀꢀ),
156.7 (C-3) ppm. EI-MS (70 eV) m/z (%): 481 [M+] (47), 228 (18),
91 (100).
2.4.12. Synthesis of 17˛-[4-(4-methoxyphenyl)-1H-1,2,3-triazol-
1-yl]-5˛-androst-2-ene
(11b)
Compound 8 and 4-methoxyphenylacetylene (9b, 132 mg) were
used for the synthesis as described in Section 2.4. After purifica-
tion, 11b was obtained as a white solid (345 mg). Mp 243–245 ◦C;
Rf = 0.46 (ss E). Anal. Calcd. for C28H37N3O: C, 77.92; H, 8.64. Found:
C, 78.08; H, 8.76. 1H NMR (500 MHz, CDCl3): ı = 0.30 (m, 1H), 0.60
(m, 1H), 0.73 (s, 3H, 19-H3), 0.96 (s, 3H, 18-H3), 1.04 (m, 1H),
1.15–1.88 (overlapping m, 14H), 2.08 (m, 1H), 2.28 (m, 1H), 2.52 (m,
1H), 3.84 (s, 3H, 4ꢀꢀ-OMe), 4.62 (d, 1H, J = 7.5 Hz, 17-H), 5.55 (m, 2H,
2-H and 3-H), 6.96 (d, 2H, J = 8.7 Hz, 3ꢀꢀ-H and 5ꢀꢀ-H), 7.58 (s, 1H, 5ꢀ-
H), 7.78 (d, 2H, J = 8.7 Hz, 2ꢀꢀ-H and 6ꢀꢀ-H) ppm. 13C NMR (125 MHz,
MeOD/CDCl3 = 10:90): ı = 11.1 (C-19), 18.0 (C-18), 17.7 (CH2), 24.6
(CH2), 28.1 (2C, 2 × CH2), 29.7 (CH2), 31.5 (CH2), 32.1 (CH2), 34.1
(C-10), 35.4 (CH), 39.1 (CH2), 40.8 (CH), 45.8 (C-13), 49.5 (CH), 52.8
(CH), 54.8 (4ꢀꢀ-OMe), 70.1 (C-17), 113.8 (2C, C-3ꢀꢀ and C-5ꢀꢀ) 118.8
(C-5ꢀ), 122.6 (C-1ꢀꢀ), 125.2 (2C, C-2 and C-3), 126.5 (2C, C-2ꢀꢀ and C-
6ꢀꢀ), 146.3 (C-4ꢀ), 159.1 (C-4ꢀꢀ) ppm. EI-MS (70 eV) m/z (%): 431 [M+]
(63), 403 (95), 388 (76), 282 (31), 175 (55), 147 (63), 132 (100), 91
(57), 79 (50), 67 (35), 55 (31).
2.4.10. Synthesis of 3-benzyloxy-17˛-[4-cyclohexyl-1H-1,2,3-
triazol-1-yl]estra-1,3,5(10)-triene
(10j)
2.4.13. Synthesis of 17˛-[4-(4-fluorophenyl)-1H-1,2,3-triazol-1-
yl]-5˛-androst-2-ene
Compound 7 and cyclohexylacetylene (9j, 0.13 mL) were used
for the synthesis as described in Section 2.4. After purification, 10j
was obtained as a white solid (392 mg). Mp 120–122 ◦C; Rf = 0.35
(ss E). Anal. Calcd. for C33H41N3O: C, 79.96; H, 8.34. Found: C,
80.08; H, 8.49. 1H NMR (500 MHz, CDCl3): ı = 0.45 (m, 1H), 0.97
(s, 3H, 18-H3), 1.29 (m, 1H), 1.38–1.56 (overlapping m, 9H), 1.74
(m, 1H), 1.81 (m, 3H), 1.97 (m, 1H), 2.08 (m, 3H), 2.17 (m, 2H),
2.33 (m, 1H), 2.52 (m, 1H), 2.78 (m, 1H), 2.86 (m, 2H, 6-H2), 4.59
(dd, 1H, J = 8.3 Hz, J = 1.1 Hz, 17-H), 5.02 (s, 2H, Bn-CH2), 6.72 (d,
1H, J = 2.3 Hz, 4-H), 6.75 (dd, 1H, J = 8.6 Hz, J = 2.3 Hz, 2-H), 7.11 (d,
1H, J = 8.6 Hz, 1-H), 7.19 (s, 1H, 5ꢀꢀ-H), 7.31 (m, 1H, 4ꢀ-H), 7.37 (m,
2H, 3ꢀ-H and 5ꢀ-H), 7.42 (d, 2H, J = 7.2 Hz, 2ꢀ-H and 6ꢀ-H) ppm. 13C
NMR (125 MHz, CDCl3): ı = 18.7 (C-18), 24.9 (CH2), 26.0 (CH2), 26.1
(3C, 3 × CH2), 27.9 (CH2), 28.6 (CH2), 29.8 (CH2), 32.5 (CH2), 33.1
(2C, 2 × CH2), 35.3 (C-1ꢀꢀꢀ), 39.1 (CH), 43.1 (CH), 46.5 (C-13), 48.8
(CH), 69.9 (Bn-CH2), 70.1 (C-17), 112.3 (C-2), 114.8 (C-4), 119.6 (C-
5ꢀꢀ), 126.2 (C-1), 127.4 (2C, C-2ꢀ and C-6ꢀ), 127.8 (C-4ꢀ), 128.5 (2C,
C3ꢀ and C-5ꢀ), 132.6 (C-10), 137.3 (C-5), 137.8 (C-1ꢀ), 152.8 (C-4ꢀꢀ),
156.7 (C-3) ppm. EI-MS (70 eV) m/z (%): 495 [M+] (51), 242 (17),
91 (100).
(11c)
Compound 8 and 4-fluorophenylacetylene (9c, 0.11 mL) were
used for the synthesis as described in Section 2.4. After purifica-
tion, 11c was obtained as a white solid (352 mg). Mp 184–187 ◦C;
Rf = 0.24 (ss C). Anal. Calcd. for C27H34FN3: C, 77.29; H, 8.17. Found:
C, 77.13; H, 8.28. 1H NMR (500 MHz, CDCl3): ı = 0.29 (m, 1H), 0.61
(m, 1H), 0.74 (s, 3H, 19-H3), 0.97 (s, 3H, 18-H3), 1.03 (m, 1H), 1.20
(m, 1H), 1.27–1.45 (overlapping m, 8H), 1.52–1.70 (overlapping m,
4H), 1.74–1.87 (overlapping m, 3H), 2.08 (m, 1H), 2.30 (m, 1H),
2.54 (m, 1H), 4.63 (d, 1H, J = 7.0 Hz, 17-H), 7.11 (m, 2H, 3ꢀꢀ-H and
5ꢀꢀ-H), 7.70 (s, 1H, 5ꢀ-H), 7.86 (bs, 2H, 2ꢀꢀ-H and 6ꢀꢀ-H) ppm. 13C
NMR (125 MHz, CDCl3): ı = 11.6 (C-19), 18.6 (C-18), 20.2 (CH2), 25.2
(CH2), 28.6 (CH2), 28.7 (CH2), 30.2 (CH2), 32.0 (CH2), 32.7 (CH2), 34.6
(C-10), 35.9 (CH), 39.6 (CH2), 41.3 (CH), 46.2 (C-13), 49.9 (CH), 53.2
(CH), 70.8 (C-17), 115.8 (d, 2C, J = 21.7 Hz, C-3ꢀꢀ and C-5ꢀꢀ), 119.6 (C-
5ꢀ), 125.7 (2C, C-2 and C-3), 127.4 (d, 2C, J = 7.7 Hz, C-2ꢀꢀ and C-6ꢀꢀ),
126.8 (C-1ꢀꢀ), 146.8 (C-4ꢀ), 163.0 (d, J = 247.3 Hz, C-4ꢀꢀ) ppm. EI-MS
(70 eV) m/z (%): 419 [M+] (46), 390 (54), 376 (42), 163 (100), 91 (49),
79 (48), 67 (33), 55 (25).
2.4.11. Synthesis of
2.4.14. Synthesis of
17˛-[4-phenyl-1H-1,2,3-triazol-1-yl]-5˛-androst-2-ene (11a)
Compound 8 and phenylacetylene (9a, 0.11 mL) were used for
the synthesis as described in Section 2.4. After purification, 11a
17˛-[4-(4-tolyl)-1H-1,2,3-triazol-1-yl]-5˛-androst-2-ene (11d)
Compound 8 and 4-tolylacetylene (9d, 0.12 mL) were used for
the synthesis as described in Section 2.4. After purification, 11d

É. Frank et al. / Steroids 76 (2011) 1141–1148
1145
was obtained as a white solid (345 mg). Mp 251–253 ◦C; Rf = 0.31
2.4.17. Synthesis of 17˛-[4-(4-tert-butylphenyl)-1H-1,2,3-
(ss D). Anal. Calcd. for C28H37N3: C, 80.92; H, 8.97. Found: C, 81.05;
H, 8.88. 1H NMR (500 MHz, CDCl3): ı = 0.29 (m, 1H), 0.60 (m, 1H),
0.73 (s, 3H, 19-H3), 0.96 (s, 3H, 18-H3), 1.04 (m, 1H), 1.20 (m,
1H), 1.26–1.47 (overlapping m, 7H), 1.51–1.70 (overlapping m, 3H),
1.74–1.88 (overlapping m, 3H), 2.08 (m, 1H), 2.28 (m, 1H), 2.37 (s,
3H, 4ꢀꢀ-H3), 2.52 (m, 1H), 4.63 (dd, 1H, J = 8.3 Hz, J = 1.2 Hz, 17-H),
5.55 (m, 2H, 2-H and 3-H), 7.23 (d, 2H, J = 8.0 Hz, 3ꢀꢀ-H and 5ꢀꢀ-H),
7.63 (s, 1H, 5ꢀ-H), 7.74 (d, 2H, J = 8.0 Hz, 2ꢀꢀ-H and 6ꢀꢀ-H) ppm. 13C
NMR (125 MHz, MeOD/CDCl3 = 5:95): ı = 11.4 (C-19), 18.4 (C-18),
20.0 (CH2), 21.0 (4ꢀꢀ-CH3), 25.0 (CH2), 28.4 (2C, 2 × CH2), 30.0 (CH2),
31.8 (CH2), 32.5 (CH2), 34.4 (C-10), 35.7 (CH), 39.4 (CH2), 41.1 (CH),
46.1 (C-13), 49.8 (CH), 53.1 (CH), 70.4 (C-17), 119.4 (C-5ꢀ), 125.4
(2C, C-2ꢀꢀ and C-6ꢀꢀ), 125.6 (2C, C-2 and C-3), 127.4 (C-1ꢀꢀ), 129.4 (2C,
C-3ꢀꢀ and C-5ꢀꢀ), 137.9 (C-4ꢀꢀ), 146.8 (C-4ꢀ) ppm. EI-MS (70 eV) m/z
(%): 415 [M+] (63), 386 (82), 372 (68), 159 (100), 131 (52), 91 (65),
79 (60), 67 (45), 55 (34).
triazol-1-yl]-5˛-androst-2-ene
(11g)
Compound 8 and 4-tert-butylphenylacetylene (9g, 0.18 mL)
were used for the synthesis as described in Section 2.4. After purifi-
cation, 11g was obtained as a white solid (384 mg). Mp 215–217 ◦C;
Rf = 0.35 (ss D). Anal. Calcd. for C31H43N3: C, 81.35; H, 9.47. Found:
C, 81.44; H, 9.63. 1H NMR (500 MHz, CDCl3): ı = 0.26 (m, 1H),
0.58 (m, 1H), 0.73 (s, 3H, 19-H3), 0.96 (s, 3H, 18-H3), 1.03 (m,
1H), 1.19 (m, 1H), 1.26–1.46 (overlapping m, 7H), 1.34 (s, 9H,
3 × tBu-CH3), 1.51–1.70 (overlapping m, 3H), 1.74–1.87 (overlap-
ping m, 3H), 2.08 (m, 1H), 2.29 (m, 1H), 2.52 (m, 1H), 4.63 (dd, 1H,
J = 8.4 Hz, J = 1.2 Hz, 17-H), 5.54 (m, 2H, 2-H and 3-H), 7.45 (d, 2H,
J = 8.3 Hz, 3ꢀꢀ-H and 5ꢀꢀ-H), 7.65 (s, 1H, 5ꢀ-H), 7.79 (d, 2H, J = 8.3 Hz,
2ꢀꢀ-H and 6ꢀꢀ-H) ppm. 13C NMR (125 MHz, CDCl3): ı = 11.6 (C-19),
18.6 (C-18), 20.2 (CH2), 25.2 (CH2), 28.6 (2C, 2 × CH2), 30.2 (CH2),
31.3 (3C, 3 × tBu-CH3), 31.9 (CH2), 32.6 (CH2), 34.6 (2C, 4ꢀꢀ-tBu-
C and C-10), 35.9 (CH), 39.5 (CH2), 41.2 (CH), 46.3 (C-13), 49.8
(CH), 53.2 (CH), 70.3 (C-17), 119.4 (C-5ꢀ), 125.3 (2C) and 125.7
(2C): C-2ꢀꢀ, C-3ꢀꢀ, C-5ꢀꢀ and C-6ꢀꢀ, 125.8 (2C, C-2 and C-3), 128.0
(C-1ꢀꢀ), 146.7 (C-4ꢀ), 151.1 (C-4ꢀꢀ) ppm. EI-MS (70 eV) m/z (%):457
[M+] (99), 429 (100), 414 (75), 201 (56), 91 (42), 79 (39), 67
(27).
2.4.15. Synthesis of
17˛-[4-(4-ethylphenyl)-1H-1,2,3-triazol-1-yl]-5˛-androst-2-ene
(11e)
Compound 8 and 4-ethylacetylene (9e, 0.13 mL) were used for
the synthesis as described in Section 2.4. After purification, 11e
was obtained as a white solid (369 mg). Mp 214–216 ◦C; Rf = 0.32
(ss D). Anal. Calcd. for C29H39N3: C, 81.07; H, 9.15. Found: C, 80.94;
H, 9.23. 1H NMR (500 MHz, CDCl3): ı = 0.29 (m, 1H), 0.60 (m, 1H),
0.73 (s, 3H, 19-H3), 0.96 (s, 3H, 18-H3), 1.04 (m, 1H), 1.18 (m,
1H), 1.25 (t, 3H, J = 7.6 Hz, 4ꢀꢀ-CH2CH3), 1.26–1.46 (overlapping m,
7H), 1.51–1.70 (overlapping m, 3H), 1.74–1.88 (overlapping m, 3H),
2.08 (m, 1H), 2.29 (m, 1H), 2.52 (m, 1H), 2.68 (q, 2H, J = 7.6 Hz, 4ꢀꢀ-
CH2CH3), 4.63 (dd, 1H, J = 8.4 Hz, J = 1.2 Hz, 17-H), 5.54 (m, 2H, 2-H
and 3-H), 7.25 (d, 2H, J = 8.0 Hz, 3ꢀꢀ-H and 5ꢀꢀ-H), 7.63 (s, 1H, 5ꢀ-H),
7.77 (d, 2H, J = 8.0 Hz, 2ꢀꢀ-H and 6ꢀꢀ-H) ppm. 13C NMR (125 MHz,
MeOD/CDCl3 = 10:90): ı = 11.2 (C-19), 15.2 (4ꢀꢀ-CH2CH3), 18.2 (C-
18), 19.9(CH2), 24.9(CH2), 28.3(2C, 2 × CH2), 28.4(CH2), 29.9(CH2),
31.8 (CH2), 32.4 (CH2), 34.3 (C-10), 35.7 (CH), 39.3 (CH2), 41.0 (CH),
46.0 (C-13), 49.8 (CH), 53.0 (CH), 70.3 (C-17), 119.5 (C-5ꢀ), 125.4
(2C, C-2ꢀꢀ and C-6ꢀꢀ), 125.5 (2C, C-2 and C-3), 127.5 (C-1ꢀꢀ), 128.1 (2C,
C-3ꢀꢀ and C-5ꢀꢀ), 144.3 (C-4ꢀꢀ), 146.8 (C-4ꢀ) ppm. EI-MS (70 eV) m/z
(%): 429 [M+] (48), 400 (81), 386 (76), 173 (100), 130 (47), 91 (66),
79 (61), 67 (44), 55 (33).
2.4.18. Synthesis
of17˛-[4-cyclopropyl-1H-1,2,3-triazol-1-yl]-5˛-androst-2-ene
(11h)
Compound 8 and cyclopropylacetylene (9h, 0.09 mL) were used
for the synthesis as described in Section 2.4. After purification, 11h
was obtained as a white solid (285 mg). Mp 122–124 ◦C; Rf = 0.31
(ss E). Anal. Calcd. for C24H35N3: C, 78.85; H, 9.65. Found: C, 78.76;
H, 9.80. 1H NMR (500 MHz, CDCl3): ı = 0.20 (m, 1H), 0.60 (m, 1H),
0.72 (s, 3H, 19-H3), 0.85 (m, 3H), 0.91 (s, 3H, 18-H3), 0.93 (m,
2H), 1.02 (m, 1H), 1.18 (m, 1H), 1.26–1.51 (overlapping m, 7H),
1.59–1.78 (overlapping m, 3H), 1.84 (m, 2H), 1.94 (m, 1H), 2.00 (m,
1H), 2.19 (m, 1H), 2.45 (m, 1H), 4.50 (dd, 1H, J = 8.5 Hz, J = 1.5 Hz,
17-H), 5.55 (m, 2H, 2-H and 3-H), 7.13 (s, 1H, 5ꢀ-H) ppm. 13C NMR
(125 MHz, CDCl3): ı = 6.7 (C-1ꢀꢀ), 7.7 (2C, C-2ꢀꢀ and C-3ꢀꢀ), 11.6 (C-
19), 18.5 (C-18), 20.2 (CH2), 25.1 (CH2), 28.5 (CH2), 28.6 (CH2), 30.2
(CH2), 31.9 (CH2), 32.5 (CH2), 34.6 (C-10), 35.9 (CH), 39.6 (CH2),
41.3 (CH), 46.1 (C-13), 49.8 (CH), 53.1 (CH), 70.1 (C-17), 119.9
(C-5ꢀ), 125.7 (2C, C-2 and C-3), 149.2 (C-4ꢀ) ppm. EI-MS (70 eV)
m/z (%): 365 [M+] (25), 322 (83), 108 (100), 91 (42), 79 (46), 67
(37).
2.4.16. Synthesis of 17˛-[4-(4-propylphenyl)-1H-1,2,3-triazol-1-
yl]-5˛-androst-2-ene
(11f)
Compound 8 and 4-propylacetylene (9f, 0.16 mL) were used for
the synthesis as described in Section 2.4. After purification, 11f was
obtained as a white solid (382 mg). Mp 192–194 ◦C; Rf = 0.48 (ss D).
Anal. Calcd. for C30H41N3: C, 81.21; H, 9.31. Found: C, 81.40; H, 9.22.
1H NMR (500 MHz, CDCl3): ı = 0.28 (m, 1H), 0.59 (m, 1H), 0.73 (s,
3H, 19-H3), 0.95 (t, 3H, J = 7.4 Hz, 4ꢀꢀ-CH2CH2CH3), 0.96 (s, 3H, 18-
H3), 1.03 (m, 1H), 1.20 (m, 1H), 1.25–1.59 (overlapping m, 9H), 1.65
(m, 3H), 1.75 (m, 1H), 1.84 (m, 2H), 2.07 (m, 1H), 2.28 (m, 1H), 2.52
(m, 1H), 2.61 (t, 2H, J = 7.6 Hz, 4ꢀꢀ-CH2CH2CH3), 4.62 (d, 1H, J = 8.3 Hz,
17-H), 5.54 (m, 2H, 2-H and 3-H), 7.23 (d, 2H, J = 8.0 Hz, 3ꢀꢀ-H and
5ꢀꢀ-H), 7.64 (s, 1H, 5ꢀ-H), 7.77 (d, 2H, J = 8.0 Hz, 2ꢀꢀ-H and 6ꢀꢀ-H) ppm.
13C NMR (125 MHz, CDCl3): ı = 11.6 (C-19), 13.8 (4ꢀꢀ-CH2CH2CH3),
18.6 (C-18), 20.2 (CH2), 24.5 (CH2), 25.1 (CH2), 28.6 (2C, 2 × CH2),
30.2 (CH2), 31.9 (CH2), 32.6 (CH2), 34.6 (C-10), 35.9 (CH), 37.8 (CH2),
39.5 (CH2), 41.2 (CH), 46.2 (C-13), 49.8 (CH), 53.1 (CH), 70.3 (C-17),
119.3 (C-5ꢀ), 125.5 (2C, C-2ꢀꢀ and C-6ꢀꢀ), 125.7 (2C, C-2 and C-3), 128.2
(C-1ꢀꢀ), 128.9 (2C, C-3ꢀꢀ and C-5ꢀꢀ), 142.6 (C-4ꢀꢀ), 146.9 (C-4ꢀ) ppm. EI-
MS (70 eV) m/z (%): 443 [M+] 60), 415 (98), 400 (92), 187 (100), 130
(52), 115 (65), 91 (73), 79 (66), 67 (47), 55 (37).
2.4.19. Synthesis of
17˛-[4-cyclopentyl-1H-1,2,3-triazol-1-yl]-5˛-androst-2-ene
(11i)
Compound 8 and cyclopentylacetylene (9i, 0.12 mL) were used
for the synthesis as described in Section 2.4. After purification, 11i
was obtained as a white solid (295 mg). Mp 145–147 ◦C; Rf = 0.24 (ss
E). Anal. Calcd. for C26H39N3: C, 79.34; H, 9.99. Found: C, 79.46; H,
10.11. 1H NMR (500 MHz, CDCl3): ı = 0.20 (m, 1H), 0.60 (m, 1H),
0.73 (s, 3H, 19-H3), 0.91 (s, 3H, 18-H3), 1.03 (m, 1H), 1.19 (m,
1H), 1.25–1.87 (overlapping m, 19H), 2.01 (m, 1H), 2.10 (m, 2H),
2.22 (m, 1H), 2.45 (m, 1H), 3.18 (m, 1H), 4.51 (dd, 1H, J = 8.5 Hz,
J = 1.5 Hz, 17-H), 5.53 (m, 2H, 2-H and 3-H), 7.14 (s, 1H, 5ꢀ-H) ppm.
13C NMR (125 MHz, CDCl3): ı = 11.6 (C-19), 18.6 (C-18), 20.2 (CH2),
25.1 (CH2), 25.2 (CH2), 28.6 (3C, 3 × CH2), 30.2 (CH2), 31.9 (CH2),
32.5 (CH2), 33.2 (CH2), 33.3 (CH2), 34.6 (C-10), 35.9 (CH), 36.8 (CH),
39.6 (CH2), 41.2 (CH), 46.1 (C-13), 49.8 (CH), 53.1 (CH), 70.1 (C-
17), 119.8 (C-5ꢀ), 125.7 (2C, C-2 and C-3), 151.8 (C-4ꢀ) ppm. EI-MS
(70 eV) m/z (%): 393 [M+] (56), 350 (93), 241 (53), 136 (92), 79 (100),
67 (79).

1146
É. Frank et al. / Steroids 76 (2011) 1141–1148
2.4.20. Synthesis of
25 ◦C, and the absorbance was read at 545 nm with a microplate
reader. Wells with untreated cells were utilized as controls.
All in vitro experiments were carried out on two microplates
with at least five parallel wells. Stock solutions of the tested
substances (10 mM) were prepared with DMSO. The DMSO con-
centration (0.3%) of the medium did not have any significant
effect on cell proliferation. Cisplatin was used as reference com-
pound.
17˛-[4-cyclohexyl-1H-1,2,3-triazol-1-yl]-5˛-androst-2-ene (11j)
Compound 8 and cyclohexylacetylene (9j, 0.13 mL) were used
for the synthesis as described in Section 2.4. After purification, 11i
was obtained as a white solid (342 mg). Mp 158–160 ◦C; Rf = 0.45
(ss E). Anal. Calcd. for C27H41N3: C, 79.55; H, 10.14. Found: C,
79.68; H, 10.24. 1H NMR (500 MHz, CDCl3): ı = 0.17 (m, 1H), 0.58
(m, 1H), 0.72 (s, 3H, 19-H3), 0.91 (s, 3H, 18-H3), 1.02 (m, 1H),
1.14–1.53 (overlapping m, 13H), 1.59–1.88 (overlapping m, 8H),
1.94 (m, 1H), 1.99–2.10 (m, 3H), 2.20 (m, 1H), 2.46 (m, 1H),
2.74 (m, 1H), 4.52 (dd, 1H, J = 8.5 Hz, J = 1.6 Hz, 17-H), 5.52 (m,
2H, 2-H and 3-H), 7.12 (s, 1H, 5ꢀ-H) ppm. 13C NMR (125 MHz,
CDCl3): ı = 11.6 (C-19), 18.6 (C-18), 20.2 (CH2), 25.2 (CH2), 26.0
(CH2), 26.2 (2C, 2 × CH2), 28.5 (CH2), 28.6 (CH2), 30.2 (CH2), 31.9
(CH2), 32.5 (CH2), 33.0 (CH2), 33.1 (CH2), 34.6 (C-10), 34.6 (C-
1ꢀꢀ), 35.9 (CH), 39.6 (CH2), 41.2 (CH), 46.1 (C-13), 49.8 (CH), 53.1
(CH), 70.1 (C-17), 119.5 (C-5ꢀ), 125.7 (2C, C-2 and C-3), 152.8
(C-4ꢀ) ppm. EI-MS (70 eV) m/z (%): 407 [M+] (97), 364 (87), 241
(82), 150 (76), 107 (88), 95 (92), 81 (100), 79 (98), 67 (76), 55
(52).
3. Results and discussion
For the preparation of novel triazole derivatives, two kinds of
steroidal 17␣-azides (7 and 8), readily available from estrone-3-
benzyl ether (1) or 5␣-androst-2-en-17-one (2) in a three-step
pathway, were used as starting materials (Scheme 1). Stereoselec-
tive reduction of the 17-keto group leading to 3 and 4 was followed
by tosylation to give 5 and 6, which then underwent facile SN2 sub-
stitution with sodium azide in N,N-dimethylformamide to furnish
the corresponding 17␣-azido compounds 7 and 8 [25].
CuAAC of 7 with phenylacetylene (9a) was carried out in reflux-
ing dichloromethane with CuI as catalyst (Table 1). The application
of Cu(I) salts in such reactions is known to require high temperature
or at least an amine base additive (DIPEA or Et3N) for adequate for-
mation of the Cu-acetylide complex. Moreover, certain complexing
ligands (mostly TBTA or bathophenanthroline) are often employed
in order to enhance the activity of the catalyst and to protect the
Cu(I) from oxidation. However, complete conversion of 7 with 9a
was found to occur after 24 h in the presence of triphenylphos-
phine (20 mol%) instead of an amine base, and the corresponding
1,4-disubstituted triazole (10a) was obtained in high yield. Triph-
enylphosphine is assumed to accelerate the rate of the reaction
and to improve the solubility of the catalyst by complexing to Cu(I),
since no appreciable transformation was noted without its addition
to the reaction mixture. After optimization of the reaction condi-
tions, similar cycloadditions of 7 with different terminal acetylenes
(9b–j) were performed to furnish 17␣-triazolyl derivatives (10b–j)
in good yields (Table 1). Analogously, a series of novel steroidal tri-
azoles were also synthesized by reaction of 8 with alkynes (9a–j),
and the products (11a–j) were isolated in yields of ∼80% after purifi-
cation by column chromatography.
2.5. Determination of antiproliferative activities
Cytotoxic effects were measured in vitro on three human
cell lines (ECACC; Salisbury, UK): HeLa (cervix adenocarci-
noma), MCF7 (breast adenocarcinoma) and A431 (skin epidermoid
carcinoma). The cells were cultivated in minimal essential
medium (Sigma–Aldrich, Budapest, Hungary) supplemented with
10% fetal bovine serum, 1% non-essential amino acids and an
antibiotic–antimycotic mixture. Near-confluent cells were seeded
into a 96-well plate (5000 cells/well) and, after overnight stand-
ing, the medium (200 ␮L) containing the tested compound (at 10
or 30 ␮M) was added. Following a 72-h incubation in a humidi-
fied atmosphere of 5% CO2 at 37 ◦C the living cells were assayed
by the addition of 20 ␮L of 5 mg/mL MTT [3-(4,5-dimethylthiazol-
2-yl)-2,5-diphenyltetrazolium bromide] solution [24]. MTT was
converted by intact mitochondrial reductase and precipitated
as blue crystals during a 4-h contact period. The medium was
then removed, the precipitated formazan crystals were solubi-
lized in DMSO (100 ␮L) during a 60-min period of shaking at
O
OR
N3
i
iii
H
H
H
H
H
H
H
H
H
BnO
BnO
BnO
1
3 R = H
7
ii
5 R = Ts
O
OR
N3
iii
i
H
H
H
H
H
H
H
H
H
H
H
H
2
4 R = H
8
ii
6 R = Ts
Scheme 1. Reagents and conditions: (i) KBH4, MeOH/CH2Cl2, rt, 8 h; (ii) TsCl, pyridine, rt, 72 h; (iii) NaN3, DMF, 100 ◦C, 48 h.

É. Frank et al. / Steroids 76 (2011) 1141–1148
1147
Table 1
Synthesis of steroidal 1,2,3-triazoles by CuAAC.
R
N
AB
N
N3
N
HC
C
R
7, 10
8, 11
R
9
H
H
.
BnO
CuI (10 mol%)
Ph3P (20 mol%)
CH2Cl2, 40 oC
H
H
AB
AB
7
8
10
11
H
Substrate
Acetylene
Product
Yielda (%)
85
7
10a
9a
9b
9c
9d
9e
9f
8
7
11a
10b
82
84
OMe
8
7
11b
10c
80
85
F
8
7
11c
10d
82
85
8
7
11d
10e
83
83
8
7
11e
10f
86
87
8
7
11f
10g
86
84
9g
8
7
11g
10h
84
88
9h
9i
8
7
11h
10i
78
80
8
7
11i
10j
75
79
9j
8
11j
84
a
After purification by column chromatography.
Table 2
Antiproliferative effects of the synthetized compounds.
Triazole
Growth inhibition % (SEM)
HeLa
MCF7
A431
10 ␮M
30 ␮M
10 ␮M
30 ␮M
10 ␮M
30 ␮M
10a
11a
10b
11b
10c
11c
10d
11d
10e
11e
10f
11f
10g
11g
10h
11h
10i
<25a
<25
<25
34 (1.3)
<25
42 (1.7)
<25
55 (1.4)
<25
<25
<25
<25
<25
35 (1.6)
<25
<25
35 (1.5)
30 (1.9)
26 (1.5)
<25
<25
35 (1.0)
37 (0.9)
44 (1.80)
53 (1.3)
<25
55 (1.7)
<25
31 (1.4)
<25
30 (1.0)
58 (0.9)
48 (2.0)
62 (1.6)
27 (0.9)
75 (0.7)
35 (1.7)
49 (1.0)
34 (2.2)
51 (1.5)
27 (1.9)
81 (0.1)
30 (1.7)
48 (0.6)
50 (2.0)
82 (0.8)
39 (1.9)
56 (1.8)
28 (1.0)
71 (1.4)
46 (0.8)
28 (2.4)
52 (1.2)
<25
44 (0.3)
<25
33 (1.8)
<25
30 (0.7)
<25
72 (0.5)
41 (1.8)
54 (1.4)
28 (1.9)
63 (1.1)
36 (1.4)
53 (1.7)
<25
67 (0.7)
27 (1.8)
79 (0.4)
<25
46 (0.9)
43 (2.0)
98 (0.1)
52 (2.0)
67 (1.3)
38 (1.6)
71 (0.4)
47 (0.7)
33 (1.3)
53 (1.6)
<25
79 (0.5)
28 (0.1)
39 (1.9)
<25
47 (1.6)
<25
53 (0.5)
<25
30 (1.7)
42 (1.0)
92 (0.7)
39 (1.1)
63 (2.1)
26 (2.1)
55 (1.0)
<25
<25
60 (1.0)
<25
69 (0.8)
35 (1.9)
30 (1.4)
48 (1.9)
<25
32 (1.2)
39 (1.4)
<25
27 (0.7)
47 (1.8)
52 (1.4)
46 (1.5)
40 (1.7)
35 (1.5)
52 (1.7)
11i
10j
11j
<25
24 (1.6)
29 (2.2)
Cisplatin
43 (2.3)
100 (0.3)
53 (2.3)
87 (1.2)
89 (0.5)
90 (1.8)
a
Compounds eliciting less than 25% inhibition of proliferation were considered ineffective and the exact results are not given, for simplicity.

1148
É. Frank et al. / Steroids 76 (2011) 1141–1148
In the 1H NMR spectra of compounds 10a–g and 11a–g, the
References
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11a–g), and at 7.1–7.2 ppm for those containing a cycloalkyl sub-
stituent (10h–j and 11h–j).
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attaining 50% proliferation inhibition even at 30 ␮M. Compound
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Acknowledgements
The work was supported financially by the Hungarian Sci-
entific Research Fund (OTKA PD 72403 and
K 72309). The
project named, “TÁMOP 4.2.1/B-09/1/KONV-2010-0005—Creating
the Center of Excellence at the University of Szeged” is sup-
ported by the European Union and co-financed by the European
Regional Fund. The authors thank to Mrs. Györgyi Udvarnoki
(University of Göttingen, Germany) for the mass spectra and
Mrs. Irén Forgó (University of Szeged, Hungary) for the technical
assistance.
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