Synthesis and preliminary biological evaluation of new antiproliferative aromatic analogues of 1α,25-dihydroxyvitamin D3

Article abstract of DOI:10.1016/j.ejmech.2014.07.037

In an effort to develop novel vitamin D3 analogues, a series of aromatic compounds was synthetized, using efficient Negishi cross coupling between alkenylzinc reagents of the C,D-ring moiety of vitamin D3, and various substituted aromatic halides as A-ring mimics. The study aimed at exploring the influence of the replacement of the original vitamin D3 diene by a styrene unit on the biological activities. Potency in the induction of the differentiation of HL-60 cells for the lead compound 36 was 12 fold less important than calcitriol correlating with a weaker binding affinity for VDR.

Full text of DOI:10.1016/j.ejmech.2014.07.037

European Journal of Medicinal Chemistry 86 (2014) 381e393
Contents lists available at ScienceDirect
European Journal of Medicinal Chemistry
journal homepage: http://www.elsevier.com/locate/ejmech
Original article
Synthesis and preliminary biological evaluation of new
antiproliferative aromatic analogues of 1 ,25-dihydroxyvitamin D3
a
Emmanuel Thomas, Jean-Daniel Brion, Jean-François Peyrat*
ꢀ
ꢀ
ꢀ
ꢀ
^
Laboratoire de Chimie Therapeutique, BioCIS-CNRS (UMR 8076), Universite Paris-Sud, Faculte de Pharmacie, Rue J.B. Clement, 92296 Chatenay-Malabry
Cedex, France
a r t i c l e i n f o
a b s t r a c t
Article history:
In an effort to develop novel vitamin D3 analogues, a series of aromatic compounds was synthetized,
using efficient Negishi cross coupling between alkenylzinc reagents of the C,D-ring moiety of vitamin D3,
and various substituted aromatic halides as A-ring mimics. The study aimed at exploring the influence of
the replacement of the original vitamin D3 diene by a styrene unit on the biological activities. Potency in
the induction of the differentiation of HL-60 cells for the lead compound 36 was 12 fold less important
than calcitriol correlating with a weaker binding affinity for VDR.
Received 12 March 2014
Received in revised form
10 July 2014
Accepted 10 July 2014
Available online 15 July 2014
© 2014 Elsevier Masson SAS. All rights reserved.
Keywords:
Aromatic analogues of vitamin D3
Negishi coupling reaction
Antiproliferative activity
1. Introduction
side chain in 17b position, which has a fundamental role in VDR-
binding and metabolism [22e25]. Thereafter, the X ray crystallo-
graphic studies of a complex of the natural hormone 1 and a mutant
vitamin D receptor revealed that modifications on the A-ring are
allowed [26]. Thus, several groups focused on this task to increase
the binding affinity for VDR [27,28]. From these studies, relatively
few examples of analogues having modifications at the central
dienic part were reported. So far, the most interesting compound
described is the stilbene 2. This compound displays VDR agonist
activities which were only 10 fold less potent than that of 1 and
induced only low calcemic effects [29].
In support of an ongoing medicinal chemistry program directed
toward vitamin D3 analogues, it was of interest to synthesize
compounds 3 in which the original diene was blocked in an aro-
matic nucleus and linked to a C,D ring unit. As the hydroxyl group
in C1 position of calcitriol proved to be essential for biological
activity, polyhydroxylated chains on the aromatic nucleus, as a
mimic of the original A-ring, were retained in compounds 3. In
this structural moiety, at least one of two hydroxyl groups is at the
same distance (6 carbon atoms in bold Fig. 1) of the CD-rings than
that of the hydroxyl group in C1 position in 1. The assumption was
that the introduction of rigidity in the structure, compare to the
natural conformational flexibility of vitamin D3 and analogues,
would lead to potent inductors of differentiation with low calce-
mic effects.
The hormonally active metabolite of vitamin D3, the 1a,25-
dihydroxyvitamin D3 or calcitriol [1,25(OH)2D3, 1], was known to
control calcium homeostasis and bone metabolism [1]. Comple-
mentary to its classical role, calcitriol was found to display anti-
proliferative and prodifferentiation activity [2e4]. In addition to
these biological activity, calcitriol was found to be involved in
apoptosis, angiogenesis and immunomodulation control [5]. Most
of these activities are expressed via a binding to the ubiquitous
receptor VDR [6] present in numerous tissues including skin, brain,
heart, pancreas, kidney, intestine, colon [7e11], prostate [12], ovary
and breast [7,13]. Currently, calcitriol and analogues might be po-
tential drugs for the treatment of tumors such as leukemia, breast
and prostate cancers [14e17], and, in vivo models, can potentiate
the activity of clinically anticancer agents such as cisplatin [18] or
paclitaxel [19]. However, when targeting cancers, the development
of these molecules in a therapeutic approach is severely limited by
the potent calcemic effects [20,21].
One of the strategy chosen to overcome hypercalcemic limita-
tion is the structural modification of calcitriol. Until recently, most
of developed 1a, 25-(OH)2-D3 analogues were modified at their
* Corresponding author.
E-mail address: jean-francois.peyrat@u-psud.fr (J.-F. Peyrat).
http://dx.doi.org/10.1016/j.ejmech.2014.07.037
0223-5234/© 2014 Elsevier Masson SAS. All rights reserved.

382
E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
2.1.2. Obtention of the CD-rings parts
The synthesis of the C,D-ring parts is shown in Schemes 2 and 3.
The vinyl bromide 4 and 5 (ratio E:Z ¼ 97:3) were prepared
respectively from vitamin D3 according to the Toh/Okamura pro-
tocol [31] and Trost procedure (Scheme 2) [32].
In regard to active alkyne analogues already described in the
literature, CD-ring moiety bearing an alkynyl function in the side
chain was selected (Scheme 3) [33].
Thus, the synthesis of the CD-ring indane 12a and 12b was
performed following Castedo protocol [34] from the Inhoffen-
Lythgoe diol [35]. Selective tosylation of this latter [36] followed
by protection of the secondary alcohol offered ethers 7a [37] and 7b
[38]. Substitution of the tosyl group by lithium derivatives of 8a or
8b, led to alkynes 9 (9a: 82%, 9b: 91%) which were deprotected to
afford the corresponding alcohols 10 (10a: 67%, 10b: 94%). Oxida-
tion using PDC, to avoid the cleavage of the THP group of 10b, or
PCC [36] offered the corresponding ketones 11a and 11b. The
desired E-bromoolefins 12a and 12b were finally obtained in good
overall yield through Wittig bromomethylenation [32].
Fig. 1. Vitamin D3 and targeted analogues 3.
2.1.3. Obtention of the A-ring parts
Once the CD-rings parts in our hands, the material required for
the Negishi coupling was the phenylhalides part. In our aim to
determine new structure-relationships in this series of analogues,
we decided to synthesize different A-ring portions, 1-(4-
phenylhalides)propane-1,3-diol 13 and bishydroxymethylphenyl
halides 14 and 15 (Scheme 4).
2. Results and discussion
2.1. Chemistry
2.1.1. General retrosynthesis of targeted analogues
The general pathway for the synthesis of analogues 3 follows a
convergent strategy based on an efficient Negishi coupling re-
actions between the organozinc derivatives [30] (A, Scheme 1) and
aryl halides (B, Scheme 1).
The A-ring derivatives 13 were synthesized from two commer-
cially available
products: 1,3-dibromobenzene and 3-
hydroxypropane nitrile (Scheme 5). The condensation of the
monolithian species of dibromobenzene, at ꢀ40 ꢁC, with the silyl
ether 16, offered the ketone 17 in good yield. This latter undergoes a
carbonyl reduction using NaBH4 and the resulting secondary
alcohol 18 was subsequently protected to provide the bis-silyl ether
19.
The corresponding iodide compound 13a was obtained in a 79%
yield after classical halogen metal exchange reaction [39].
Ketone 17 was used in parallel to synthesized acetonide iodide
compound 13c. Reduction and deprotection of 17 led to the diol 20
[40] which was protected as acetonide and subjected to halogen
metal exchange to offer 13c in 49% overall yields across the three
steps.
The O-bis(hydroxymethyl)phenyls 14 were obtained from
commercial 4-bromophtalic acid, after reduction in presence of
BH3$THF leading to diol 21 [41], protection as silyl ether (14a [41])
Scheme 1. Synthetic approaches.
Scheme 2. Obtention of the CD-rings parts 4 and 5. a) i) KMnO4, H2O/EtOH, ꢀ10 ꢁC to ꢀ40 ꢁC, 63%; ii) Pb(OAc)4, pyridine, CH2Cl2, 0 ꢁC, 82%; b) i) RuCl3 (0.15 equiv.), NaIO4
(3.6 equiv.), CCl4/CH3CN/H2O, r.t., 49%; c) TES-OTf, 2,6-lutidine, CH2Cl2, ꢀ78 ꢁC to r.t., 84%; d) NaHMDS (4.8 equiv.), [BrCH2(PPh3)]þBrꢀ (5 equiv.)., THF, ꢀ60 ꢁC to r.t., 51%.

E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
383
Scheme 3. Obtention of the CD-rings parts 12. a) DHP, PTSA 1 mol.%, CH2Cl2, 0 ꢁC to r.t., 7a, 84% or TES-OTf, 2,6-lutidine, ꢀ10 ꢁC to r.t., 7b, 98%; b) n-BuLi, 8a, dioxane, 5 ꢁC to r.t. then
reflux 40 h, 82%; c) n-BuLi, 8b, dioxane, 5 ꢁC to r.t. then reflux 40 h, 91%; d) amberlyst 15, MeOH, 50 ꢁC, 12 h, 67%; e) PCC, CH2Cl2, r.t. 90%; f) TBAF, THF, r.t., 94%; g) PDC, CH2Cl2, r.t.,
86%; h) NaHMDS, [BrCH2(PPh3)]þBrꢀ, THF, ꢀ60 ꢁC to r.t., 53% (for 12a and 12b).
followed by halogen/metal exchange provided the compound 14b
in 69% overall yield (Scheme 6).
The desired coupling product was isolated in 83% yield. How-
ever, the coupling of triflate compound 15 with 4, produced a very
low yield. Optimization of the reaction conditions showed that, in
this case, a temperature of 70 ꢁC and an additive (LiCl (3 equiv.))
were required [46,47]. In these conditions, compound 30 and 31
were obtained, from 15 and 4 in 52% and from 12b and 15 in 55%
yield respectively (Table 1). Note that, in our hands, tetrakis tri-
phenylphosphine palladium was always the best catalysis. The use
of Pd(dba)2/tri(2-furyl)phosphine [48,49] or Pd(dba)2/(1.1)-bisdi-
phenyl)phosphino ferrocene [50,51], led to drastic decrease of
yield, even with A-ring 15, while such palladium species were
known to be effective with triflates.
The triflate of the A-ring moiety 15 was envisaged to explore the
pseudo-halogen reactivity [42]. The synthetic pathway started from
commercial 3-hydroxyphthalic anhydride (Scheme 6) which was
reduced in phenol 22 with LiAlH4. Compound 22 was then trans-
formed into the allylic ether 23. Further diol protection and allyl
group removing [43], led to intermediate phenol 25 which was
converted to the corresponding desired triflate 15 in 78% overall
yield.
~
Mourino have reported that functionalized vinyl iodides reacted
efficiently with organozinc C,D fragments, in the presence of tet-
rakis(triphenylphosphine)palladium [30,44]. Thus, this catalyst
was chosen for the study of the Negishi cross-coupling reaction.
The organozinc derivatives was first prepared in situ by treatment
of vinyl bromides with t-BuLi, and trapping the resulting anion with
ZnBr2 (Scheme 7). The resulting vinylzinc bromide was then
coupled with aryl halides in the presence of a catalytic amount of
Pd(PPh4)3 (5 mol.%). The results are summarized in Table 1.
First attempt was performed using vinyl bromide 4 and aryl
bromide 19. Surprisingly, no reaction occurred and 19 was totally
recovered. Note that all attempts at cross coupling failed, using
diethyl ether or THF as solvent at room temperature or at 60 ꢁC.
To our delight, room temperature reaction of more reactive aryl
iodides in the presence of Pd(PPh3)4 [45], 13c and 14b, gave the
expected coupling products (26aec, 27aeb, 28 and 29) in good
yields. Results showed that the presence of three sterically hin-
dered silyl ether groups on the two coupling partners results in a
drastic decrease of yield (26b and 27a) even if activating the
coupling at higher temperature (70 ꢁC). This assumption was
verified with the replacement of the bis-silylated part 14a by 12b
bearing an acetonide group (products 26c and 27b) which offer the
desired coupling product in good yield.
In a final step, all protected compounds were next subjected to
TBAF or DOWEX resin treatment in MeOH at 60 ꢁC and to a puri-
fication by high-performance chromatography (HPLC) to offer final
compounds 32e38 in 76e96% yields (Scheme 8).
2.2. Biology: binding affinity to VDR and induction of HL-60 cell
differentiation
In vitro tests were performed on with ovarian Sf9 cells line
where the human recombinant VDR are over expressed, following
the Ross protocol [52].
The VDR affinities and potencies of induction of HL-60 cell dif-
ferentiation of the novel synthesized analogues are summarized in
Table 2 in comparison with those of the natural hormone 1. All new
synthesized compounds showed a lower binding affinity for the
VDR compare to calcitriol, despite the presence of hydroxyl groups
on the ring A mimic at the same distance (6 carbon atoms) from
rings C,D than that existing in the parent compound 1.
The introduction of rigidity in the central diene system of the
molecules reduced the affinity for the VDR. However, 3,4-
bis(hydroxymethyl)analogue 33 and 36 showed the better affinity
for VDR.
2.1.4. Negishi cross coupling
Thus, the ability of these new analogues to induce differenti-
ation of HL-60 cell [53] was tested and results are summarized in
Table 2. The established HL-60 cellular differentiation activity of
the tested compounds is 2000 to 12 fold weaker in comparison
with the hormone 1. However, compound 36 showed the best
results, with a differentiation activity 12 fold lower than that of
calcitriol 1. The influence of the alkynyl side chain is again brought
to the fore when comparing compounds 35 and 36 [a sentence has
been deleted]. The compound 36 provides new insight into the
structure-relationships of vitamine D3 analogues. A strained cen-
tral diene can exist in a compound which displayed a significant
affinity for the VDR and a moderate HL-60 cell differentiation
activity.
The coupling result between aryl bromide 19 and 4 in head, the
reactivity of 4-methoxyphenyl trifluoromethanesulfonate was
evaluated during the Negishi reaction in the same conditions.
Scheme 4. A-ring mimic parts.

384
E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
Scheme 5. Synthesis of A-ring mimic 13. a) i) n-BuLi, Et2O, ꢀ40 ꢁC, 70%; ii) 16, Et2O, ꢀ40 ꢁC, then HCl 0.5 M, 70%; b) NaBH4, THF/MeOH (1/1), 0 ꢁC, 91%; c) TBDMSCl, Imidazole,
DMAP cat., CH2Cl2, r.t., 90%. d) i) n-BuLi, THF, ꢀ78 ꢁC; ii) I2, THF, r.t., (13a ¼ 79% and 13c ¼ 87%); e) i) NaBH4, THF/MeOH (1/1), 0 ꢁC; ii) HCl 3 M, 89% for the two steps; f) 2,2-
dimethoxypropane, CH2Cl2, amberlyst 15, 63%.
3. Conclusion
(mp) were recorded on a Büchi B-450 apparatus and were uncor-
rected. NMR spectra were performed on a Bruker AMX 200 (1H,
200 MHz; 13C, 50 MHz), Bruker AVANCE 300 or Bruker AVANCE 400
(1H, 400 MHz; 13C, 100 MHz). Unless otherwise stated, CDCl3 was
In conclusion, we have described the synthesis, using Negishi
coupling reaction as a key step, and the biological evaluation of
original 1
a,25(OH)2D3 analogues bearing a mimic of the ring A
used as solvent. Chemical shifts d are in ppm, and the following
presents in the parent compound 1. To investigate structur-
eeactivity relationships, different substitutions on the ring A
mimics and on the side chain of the C,D rings part were envisaged.
In this way, an efficient synthetic route to the novel compounds
library has been developed. VDR binding affinity and HL-60 cell
differentiation revealed that compound 36 exhibited an interesting
profile despite a lower activity than calcitriol (1). However, initial
in vitro biological evaluation is not sufficient to conclude about the
impact of the rigidity of the central diene on the biological activ-
ities. The expected antitumoral activities and low calcemic effect of
analogues will be evaluated and reported separately.
abbreviations are used: singlet (s), doublet (d), triplet (t), multiplet
(m), quintet (q), broad doublet (bd), broad multiplet (bm), broad
triplet (bt) and broad singlet (bs). Elemental analyses (C, H, N) were
performed at the microanalyses Service of the Faculty of Pharmacy
^
at Chatenay-Malabry (France) with a Perkin Elmer 2400 CHNS in-
strument and were within 0.4% of the theorical values otherwise
stated. IR spectra were performed with a Bruker type Vector 22. ESI
Mass spectra were obtained using an LC Bruker Esquire electro-
spray ionization instrument. ESI-TOF IR spectra were obtained us-
ing an LCT Micromass (Waters) and IE mass spectra on Polaris
Thermoquest (Funnigan). High-performance liquid chromatog-
raphy (HPLC) c was performed on a Merck LabChrom (C-18 column
Merck lichrospher RP18 (124*4)). Optical rotations were measured
using a Perkin Elmer 241 MC.
4. Experimental
4.1. Chemistry
4.1.1. Compound 6
All glasswares were oven-dried at 140 ꢁC. Tetrahydrofuran (THF)
was distilled from sodium-benzophenone ketyl. Melting points
To a solution of Inhoffen-Lythgoe diol (1.95 g, 9.18 mmol,
1 equiv.) in fresh distillated pyridine (39 mL) at 0 ꢁC, was added p-
toluenesulfonyl chloride (2.6 g, 13.8 mmol). The mixture was stored
a night at 4 ꢁC and hydrolyzed with ice. The mixture was extracted
with Et2O. The organic layer was washed with a solution of HCl 1 M
(until pH 1), and with a saturated solution of sodium dicarbonate,
dried over Na2SO4, and evaporated. The crystals were then placed
in a dessicator for a night and give compound 6 (3.3 g, 9.18 mmol,
99%, white crystals).
Scheme 6. Synthesis of A-ring mimics 14 and 15. a) BH3$THF, THF, 0 ꢁC to ꢀ40 ꢁC, 85%;
b) TBDMSCl, Imidazole, DMAP cat., CH2Cl2, r.t., 98%; c) i) n-BuLi, THF, ꢀ78 ꢁC; ii) I2, THF,
r.t., 83%. d) LiAlH4, THF, ꢀ78 ꢁC to reflux, 86%; e) allyl bromide, K2CO3, KI 10%, acetone,
60 ꢁC, 71%; f) TBDMSCl, Imidazole, DMAP cat., CH2Cl2, r.t., 92%; g) NaBH4, Pd(PPh3)4 5%,
THF/MeOH (1/4), 0 ꢁC, 95%, h) Tf2O, Pyridine, CH2Cl2, 0 ꢁC, 89%.
Scheme 7. Negishi coupling conditions.

E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
385
Table 1
Negishi cross coupling of A and CD-rings.
A-ring
CD-ring
Coupling product
Yield (%)
0
19
4
4
26a
26a
82
13a
31a
13a
13c
13a
5
26b
26c
27a
61
5
33a
12a
67
91
91
13c
14b
14B
12b
27b
4
28
12B
29
52b
15
15
4
30
31
55b
12b
a
Same yield at 70 ꢁC.
3 eq. of LiCl and 70 ꢁC.
b

386
E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
Scheme 8. Coupling products and corresponding deprotected final compounds 32e38. a) TBAF, THF, r.t., 48 h; b) Dowex 50WN2-200, MeOH 95%, 60 ꢁC, 2 h.
Rf ¼ 0.21 (cyclohexane/AcOEt: 75/25). m.p. (AcOEt) ¼ 110 ꢁC
CDCl3): d 4.69 (1H, bs), 4.54 (1H, bs), 3.33 (2H, m), 2.12 (1H, m), 2.04
(Litt. 109e110 ꢁC). IR (film, cmꢀ1):
n
3344, 2931, 2880, 2864, 1697,
(1H, m), 2.12e0.95 (12H, m), 1.27 (6H, s), 0.91 (3H, d, 3J ¼ 6.5 Hz),
1457, 1360, 1067, 1034, 987, 941, 629. 1H RMN (400 MHz, CDCl3):
0.77 (3H, s), 0.70 (9H, s), 0.01 (6H, s). 13C RMN (100 MHz, CDCl3):
d 94.2, 86.6, 81.3, 76.8, 66.2, 62.3, 55.6, 52.1, 42.0, 40.4, 35.1, 33.2,
d
4.05 (1H, bs), 3.6 (1H, dd, 3J ¼ 10.5 Hz, 3J ¼ 3.2 Hz), 3.33 (1H, dd,
3J ¼ 10.5 Hz, 3J ¼ 6.6 Hz), 2.02e1.07 (13H, m), 1.01 (3H, d,
33.1, 32.4, 32.3, 26.5, 25.7, 25.6, 23.8, 22.4, 18.9, 17.7, 17.3, 17.1,
3J ¼ 6.6 Hz), 0.93 (3H, s). 13C RMN (100 MHz, CDCl3):
d
69.1, 67.6,
13.3, ꢀ3.2. MS (ESIþ) m/z: 499.4 ((MþNa)þ, 100).
52.9, 52.3, 41.7, 40.1, 38.1, 33.4, 26.5, 22.5, 17.3, 16.5, 13.4. MS (ESIþ)
m/z: 213.1 ((MþH)þ, 100), 193.1 (30), 177.2 (100), 135.1 (28).
4.1.3. Compound 9b
To a solution of alkyne 8b (2.8 g, 16.8 mmol, 4 equiv.) in dry
dioxane (50 mL) at ꢀ5 ꢁC, was added BuLi (6.65 mL, 16.6 mmol,
4 equiv.). The mixture was stirred for 30 min at ꢀ5 ꢁC, then 1 h at r.t.
A solution of 7b (2 g, 4.4 mmol, 1 equiv.) in dioxane (10 mL) was
then added dropwise, and the mixture was heated to reflux. After
40 h, the mixture was poured into a mixture of NaHCO3 in ice. The
mixture was extracted with AcOEt, washed with a solution of
saturated NaCl, dried over Na2SO4, and evaporated. The residue was
purified by flash chromatography on silica gel (cyclohexane/AcOEt:
95/5) to give compound 9b [1.9 g, 4 mmol, 91%, colorless oil].
Rf ¼ 0.5 (cyclohexane/AcOEt: 95/5). 1H RMN (400 MHz, CDCl3):
4.1.2. Compound 9a
To a solution of alkyne 8a (2.64 g, 13.3 mmol, 4 equiv.) in dry
dioxane (40 mL) at ꢀ5 ꢁC, was added BuLi (5.32 mL, 13.3 mmol,
4 equiv.). The mixture was stirred for 30 min at ꢀ5 ꢁC, then 1 h at
r.t. A solution of 7a (1.5 g, 3.3 mmol, 1 equiv.) in dioxane (7 mL) was
then added dropwise, and the mixture was heated to reflux. After
40 h, the mixture was poured into a mixture of NaHCO3 in Ice. The
mixture was extracted with AcOEt, washed with a solution of
saturated NaCl, dried over Na2SO4, and evaporated. The residue was
purified by flash chromatography on silica gel (cyclohexane/AcOEt:
95/5) to give compound 9a [1.3 g, 2.9 mmol, 82%, brown oil].
d
5.13 (1H, bs), 4.10 (1H, bs), 3.86 (1H, m), 3.43 (1H, m), 2.46 (3H, s),
2.22 (1H, dd, 3J ¼ 4.3 Hz, 2J ¼ 15.6 Hz), 2.09 (1H, m), 1.97 (1H, m),
1.82 (2H, m), 1.72 (1H, m),1.65e1.30 (11H, m),1.58 (1H, m),1.48 (6H,
s), 1.07 (3H, d, 3J ¼ 6.7 Hz), 0.96 (9H, t, 3J ¼ 6.7 Hz), 0.94 (3H, s), 0.59
Rf ¼ 0.7 (cyclohexane/AcOEt: 8/2). IR (film, cmꢀ1):
n 2929, 2855,
1462, 1376, 1248, 1200, 1023, 1001, 835, 775. 1H RMN (400 MHz,
(6H, q, 3J ¼ 8.1 Hz). 13C RMN (100 MHz, CDCl3):
d 96.2, 84.6, 83.5,
Table 2
71.8, 70.3, 62.8, 56.5, 53.9, 42.8, 41.5, 35.8, 35.3, 32.7, 31.6, 30.6, 27.7,
26.4, 26.2, 23.8, 20.8, 19.5, 18.4, 14.3, 7.3, 5.6. MS (ESIþ) m/z: 499.4
((MþNa)þ, 100).
VDR binding properties and HL-60 differentiating activities of vitamin D3 analogues.
Compound
% Inhibition of control
HL-60 cell differentiation
IC50
M)b
specific binding to VDRa
(m
1
100
13
23
9
12
74
30
21
0.05 0.04
5.4 0.12
1.4 0.42
7.8 4.82
63.2 5.40
0.6 0.04
32.4 8.17
>100
4.1.4. Compound 10a
32
33
34
35
36
37
38
To a solution of 9a (1.1 g, 2.3 mmol, 1 equiv.) in dry MeOH
(20 mL), was added Amberlyst 15® (1 g). The mixture was heated at
50 ꢁC for 1 h, filtered over a pad of silica, washed with MeOH and
concentrated in vacuo. The residue was purified by flash chroma-
tography on silica gel (cyclohexane/AcOEt: 93/7) to give compound
10a [734 mg, 1.5 mmol, 67%, colorless oil].
a
Competitive binding of 1
a
,25-(OH)2D3 (1) and the synthesized vitamin D ana-
Rf ¼ 0.2 (cyclohexane/AcOEt: 95/5). IR (film, cmꢀ1):
n 3420, 2981,
logues to the human recombinant vitamin D receptor.
2856, 1472, 1376, 1246, 1159, 1036, 835, 775. 1H RMN (400 MHz,
b
Induction of differentiation of HL-60 promyelocytes to monocytes by 1a,25-
(OH)2D3 and the synthesized analogues.
CDCl3):
d
4.08 (1H, bs), 2.22 (1H, dd, 3J ¼ 3.5 Hz, 2J ¼ 16.5 Hz), 2.02

E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
387
(1H, dd, 3J ¼ 7.5 Hz, 2J ¼ 16.6 Hz), 1.98 (2H, m), 1.71e1.13 (10H, m),
4.1.8. Compound 11b
1.56 (1H, m), 1.43 (6H, s), 1.04 (3H, d, 3J ¼ 6.6 Hz), 0.94 (3H, s), 0.85
To a solution of alcohol 10b (1.3 g, 3.59 mmol, 1 eq.) in dry
CH2Cl2 (45 mL) was added pyridinium dichromate (3.76 g, 10 mmol,
3 equiv.). The mixture was stirred for 4 h and was filtered over a pad
of silica (elution with EtOAc). After concentration in vacuo, the
residue was purified by flash chromatography (Cyclohexane/AcOEt:
8/2) to give the ketone 11b [1.1 g; 3 mmol, 86%, colorless oil].
ꢀ
(9H, s), 0.0 (6H, s). 13C RMN (100 MHz, CDCl3):
d 86.9, 81.3, 69.3,
66.4, 55.5, 52.6, 41.8, 40.2, 35.0, 33.6, 33.4, 33.3, 27.0, 25.7, 25.5,
22.5, 19.0, 17.4, 17.2, 13.6, ꢀ4.1. MS (EIþ, 70 eV) m/z: 392 (2), 335
(80), 259 (25), 201 (58), 163 (33), 81 (100), 73 (100), 55 (96).
Rf ¼ 0.59 (cyclohexane/AcOEt: 8/2). [
a]
25 ꢀ43.7ꢁ (c 0.17, CHCl3).
D
4.1.5. Compound 10b
1H RMN (400 MHz, CDCl3):
d
5.29 (1H, bs), 4.03 (1H, m), 3.59 (1H,
To a solution of silyl ether 9b (1.8 g, 3.8 mmol, 1 equiv.) in dry
THF (30 mL) were added molecular sieves 4 Å, and a solution of
tetrabutyl ammonium fluoride (7.55 mL, 7.55 mmol, 2 equiv.). The
mixture was stirred for a night at r.t. After hydrolysis, the mixture
was extracted with AcOEt, washed with a solution of saturated
NaCl, dried over Na2SO4, and evaporated. The crude residue was
purified by flash chromatography on silica gel (cyclohexane/AcOEt:
9/1) to give compound 10b [1.3 g, 3.61 mmol, 94%, colorless oil].
m), 2.72 (1H, dd, 3J ¼ 6 Hz, 2J ¼ 5.6 Hz), 2.2e1.2 (19H, m), 1.63 (3H,
s), 1.58 (3H, s), 1.54 (1H, m), 1.26 (3H, d, 3J ¼ 5.8 Hz), 0.89 (3H, s). 13
C
RMN (100 MHz, CDCl3):
d 211.4, 95.9, 84.0, 82.2, 71.3, 63.2, 61.7,
55.4, 49.5, 40.7, 38.7, 34.9, 31.9, 31.6, 30.9, 27.1, 25.6, 25.3, 23.8, 20.5,
18.9, 18.8, 12.5. MS (ESIþ) m/z: 406.2 ((Mþ2Na)þ, 100), 383.2
((MþNa)þ, 5).
4.1.9. Compound 12b
IR (film, cmꢀ1):
n
3471, 2982, 2926, 2851, 2660, 1613, 1568, 1360,
To a suspension of (bromomethyl)triphenylphosphonium bro-
mide (6.65 g, 15.2 mmol, 5 equiv.) in dry THF (33 mL) at ꢀ60 ꢁC, was
added dropwise a solution of NaHMDS in THF (7.32 mL, 14.6 mmol,
4.8 equiv.). The reaction mixture was stirred for 1 h, and a yellow
color was observed. A solution of ketone 11b (1.1 g, 3.05 mmol,
1 equiv.) in THF (6.5 mL) was added dropwise. After 2 h of stirring,
the mixture became brown and cyclohexane was then added. The
mixture was filtered over a pad of silica (elution with cyclohexane)
and solvents were dried in vacuo. The crude residue was purified by
flash chromatography (cyclohexane/AcOEt: 98/2) to give the com-
pound 12b [726 mg, 1.66 mmol, 53%, colorless oil].
1109, 1022, 885, 685. 1H RMN (400 MHz, CDCl3):
d 5.06 (1H, bs),
3.94 (1H, bs), 3.80 (1H, m), 3.37 (1H, m), 2.22 (1H, dd, 3J ¼ 4.1 Hz,
2J ¼ 15.6 Hz), 1.91e1.23 (19H, m), 1.53 (1H, m), 1.47 (6H, s), 1.07 (3H,
d, 3J ¼ 6.5 Hz), 0.94 (3H, s). 13C RMN (100 MHz, CDCl3):
d 96.3, 84.6,
83.5, 71.9, 68.7, 62.9, 56.5, 53.9, 42.6, 41.6, 35.8, 34.9, 32.7, 31.6, 30.6,
27.7, 26.3, 26.2, 23.4, 20.8, 19.5, 18.4, 14.2. MS (ESIþ) m/z: 385.3
((MþNa)þ, 100).
4.1.6. Compound 11a
To
a
suspension of pyridinium chlorochromate (576 mg,
Rf ¼ 0.46 (cyclohexane/AcOEt: 95/5). 1H RMN (400 MHz,
2.67 mmol, 3 equiv.) in dry CH2Cl2 (16 mL), was added dropwise a
solution of alcohol 10a (350 mg, 0.89 mmol, 1 equiv.) in CH2Cl2
(4 mL). The mixture was stirred for 4 h at r.t., filtered over a pad of
silica, washed with CH2Cl2, and concentrated in vacuo. The residue
was purified by flash chromatography on silica gel (cyclohexane/
AcOEt: 95/5) to give compound 11a [312 mg, 0.8 mmol, 90%,
colorless oil].
CD3COCD3): d 5.62 (1H, bs); 5.01 (1H, bs), 3.75 (1H, m), 3.34 (1H, m),
2.72 (1H, m), 2.1e1.2 (20H, m), 1.35 (3H, s), 1.29 (3H, s), 0.97 (3H, d,
3J ¼ 6.2 Hz), 0.48 (3H, s). 13C RMN (100 MHz, CD3COCD3):
d 144.8,
97.2, 95.2, 83.9, 82.3, 70.8, 61.9, 55.6, 54.4, 45.2, 39.5, 35.3, 31.7, 30.7,
30.6, 29.7, 26.9, 25.4, 25.2, 22.2, 21.7, 19.8, 18.6, 11.7. MS (ESIþ) m/z:
460 ((MþNa)þ, 100). Anal. Calcd for [C24H37BrO2]: C, 65.89, H, 8.57.
Found: C, 65.81, H 8.48.
Rf ¼ 0.33 (cyclohexane/AcOEt: 95/5). [
a
]
25 þ23.5ꢁ(c 0.21, CHCl3).
D
IR (film, cmꢀ1):
n
2956, 2930, 2856, 1716, 1462, 1245, 1159, 1036,
4.1.10. Compound 17
834, 775. 1H RMN (400 MHz, CDCl3):
d
2.54 (1H, dd, 3J ¼ 7.8 Hz,
To a solution of 1.3-dibromobenzene (5 g, 212 mmol, 2 equiv.) in
dry Et2O (30 mL) at ꢀ78 ꢁC, was added dropwise a solution of n-
BuLi 1.6 M in Et2O (13.5 mL, 216 mmol, 2.04 equiv.). The mixture
was allowed to ꢀ45 ꢁC and stirred 15 min.. A solution of nitrile 16
(1.96 g, 106 mmol, 1 equiv.) in dry Et2O (10 mL) was then added
dropwise at ꢀ40 ꢁC. The mixture was stirred at this temperature for
1 h. Then the mixture was allowed to come to r.t. After hydrolysis,
the mixture was extracted with AcOEt, washed with a solution of
saturated NaCl, dried over Na2SO4, and evaporated. The residue was
purified by flash chromatography (cyclohexane/AcOEt: 98/2) to
give the compound 17 [2.55 g, 7.43 mmol, 70%, yellow oil].
2J ¼ 7.6 Hz), 2.29 (2H, m), 2.13 (3H, m), 2.05e1.55 (8H, m), 1.65 (1H,
m),1.45 (6H, s),1.13 (3H, d, 3J ¼ 6.3 Hz), 0.87 (3H, s), 0.85 (9H, s), 0.10
(6H, s). 13C RMN (100 MHz, CDCl3):
d 209.7, 87.4, 81.8, 67.1, 62.0,
56.0, 49.9, 41.1, 39.4, 35.8, 33.7, 27.9, 26.2, 26.1, 24.3, 19.7, 19.6, 17.4,
12.7, 0.0. MS (ESIþ) m/z: 413.3 ((MþNa)þ, 100).
4.1.7. Compound 12a
To a suspension of (bromomethyl)triphenylphosphonium bro-
mide (5.12 g, 11 mmol, 5 equiv.) in dry THF (9 mL) at ꢀ60 ꢁC, was
added dropwise a solution of NaHMDS in THF (1.84 mL, 3.68 mmol,
4.8 equiv.). The reaction mixture was stirred for 1 h, and a yellow
color was observed. A solution of ketone 11a (300 mg, 0.77 mmol,
4.8 equiv.) in THF (1.5 mL) was added dropwise. After 2 h of stirring,
the mixture became brown and cyclohexane was then added. The
mixture was filtered over a pad of silica (elution with cyclohexane)
and solvents were dried in vacuo. The crude residue was purified by
flash chromatography (cyclohexane) to give the compound 12a
[190 mg, 0.41 mmol, 53%, colorless oil].
Rf ¼ 0.46 (cyclohexane/AcOEt: 98/2). IR (film, cmꢀ1):
n 2954,
2929, 2856, 1687. RMN (400 MHz, CDCl3):
d
8.15 (1H, t, 4J ¼ 1.7 Hz,
H5), 7.85 (1H, dt, 3J ¼ 7.7 Hz, 4J ¼ 1.7 Hz), 7.75 (1H, dt, 3J ¼ 7.7 Hz,
4J ¼ 1.5 Hz), 7.25 (1H, dd, 3J ¼ 7.7 Hz, 3J ¼ 1.7 Hz), 4.00 (2H, t,
3J ¼ 6.4 Hz), 3.11 (2H, t, 3J ¼ 6.4 Hz), 0.80 (9H, s), 0.00 (6H, s). 13
C
RMN (100 MHz, CDCl3):
d 197.8, 139,1, 135.7, 131.2, 130.0, 126.6,
122.8, 59.1, 41.6, 25.7, 18.1, 0.0. MS (ESIþ) m/z: 365 ((MþNa)þ, 100),
208 (85).
Rf ¼ 0.75 (cyclohexane). 1H RMN (400 MHz, CD3COCD3):
d
5.45
4.1.11. Compound 18
(1H, bs), 2.65 (1H, dd, 3J ¼ 7.2 Hz, 2J ¼ 7.4 Hz, H7), 2.05e1.1 (14H, m),
1.25 (6H, s, H), 0.89 (3H, d, 3J ¼ 6.7 Hz), 0.68 (9H, s), 0.41 (3H, s), 0.0
To a solution of ketone 17 (1.2 g, 3.5 mmol) in 25 mL of a solution
of THF/MeOH (1/1, v/v) at 0 ꢁC, was added NaBH4 (530 mg,
13.5 mmol, 2.04 equiv.). The mixture was stirred during 12 h at r.t.
After hydrolysis, the aqueous phase was extracted with Et2O. The
organic phase was washed with a saturated solution of NaCl, dried
over Na2SO4, and evaporated. The residue was purified by flash
(6H, s). 13C RMN (100 MHz, CD3COCD3):
d 144.8, 97.1, 86.5, 81.1, 66.2,
55.5, 54.4, 45.1, 39.4, 35.4, 32.8, 30.6, 27.0, 25.2, 25.1, 22.2, 21.6, 18.7,
18.4, 11.7, ꢀ3.6. MS (ESIþ) m/z: 490.3 ((MþNa)þ, 100). Anal. Calcd
for [C25H43BrOSi]: C, 64.21, H, 9.27. Found: C, 64.08, H 9.12.

388
E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
chromatography (cyclohexane/AcOEt: 9/1) to give the compound
1.55 (3H, s). 13C RMN (100 MHz, CD3COCD3):
d 145.8, 129.9, 129.8,
18 [1.08 g, 3.1 mmol, 91%, colorless oil].
128.4, 124.4, 121.7, 96.2, 69.9, 59.3, 33.3, 29.6, 18.5.
Rf ¼ 0.33 (cyclohexane/AcOEt: 9/1). IR (film, cmꢀ1):
n
d
3417, 2953,
7.43 (1H, t,
2928, 2883, 2857, 1471, 1427. RMN (400 MHz, CDCl3):
4J ¼ 1.3 Hz), 7.29 (1H, dt, 3J ¼ 7.6 Hz, 4J ¼ 1.7 Hz), 7.18 (1H, dt,
3J ¼ 7.1 Hz, 4J ¼ 1.4 Hz), 7.10 (1H, dd, 3J ¼ 7.6 Hz, 3J ¼ 7.1 Hz), 4.82
(1H, t, 3J ¼ 6.2 Hz), 3.75 (2H, t, 3J ¼ 6.4 Hz), 1.82 (2H, t, 3J ¼ 6.3 Hz),
4.1.15. Compound 13c
To a solution of aryl bromide 13b (680 mg, 2.42 mmol, 1 equiv.)
in dry THF (13 mL), at ꢀ78 ꢁC, was added dropwise a solution of n-
BuLi (1.18 mL, 2.95 mmol, 1.2 equiv.). The yellow mixture was stir-
red 30 min and a solution of iodide (1.55 g, 6.12 mmol, 2.5 equiv.) in
dry THF (5 mL) was added dropwise. The reaction mixture was
stirred for 2 h at ꢀ78 ꢁC and for a night at r.t. After hydrolysis by
addition of a saturated solution of Na2S2O3 the aqueous phase was
extracted with AcOEt. The organic layer was washed with a solution
of saturated NaCl, dried over Na2SO4, and evaporated. The residue
was purified by flash chromatography (cyclohexane/AcOEt: 9/1) to
give the compound 13c [680 mg, 2.14 mmol, 87%, pale yellow oil].
0.81 (9H, s), 0.00 (6H, s). 13C RMN (100 MHz, CDCl3):
d 146.8, 130.1,
129.7, 128.7, 124.2, 122.4, 73.4, 61.9, 4.3, 25.7 (X3), 18.0, 0.0. MS
(ESIþ) m/z: 346 ((MþH)þ, 100).
4.1.12. Compound 19
To a solution of alcohol 18 (630 mg, 1.83 mmol, 1 equiv.), in
presence of a catalytic amount of DMAP (20 mg), in dry CH2Cl2 at
r.t., was added tert-butyldimethylsilyl chloride (551 mg, 3.66 mmol,
2 equiv.). The mixture was stirred for a night at r.t. After hydrolysis,
the mixture was extracted with CH2Cl2, washed with a solution of
saturated NaCl, dried over Na2SO4, and evaporated. The residue was
purified by flash chromatography (cyclohexane/AcOEt: 8/2) to give
the compound 19 [755 mg, 1.65 mmol, 90%, colorless oil].
Rf ¼ 0.35 (cyclohexane/AcOEt: 9/1). IR (film, cmꢀ1):
n 2990,
2952, 2867, 1566, 1376, 1196, 1161, 1105, 969, 780, 694. 1H RMN
(400 MHz, CDCl3):
d
7.73 (1H, t, 4J ¼ 1.6 Hz), 7.60 (1H, dt, 3J ¼ 7.7 Hz,
4J ¼ 1.6 Hz), 7.34 (1H, dm, 3J ¼ 7.7 Hz), 7.07 (1H, t, 3J ¼ 7.8 Hz), 4.86
(1H, dd, 3J ¼ 3.1 Hz, 3J ¼ 11.5 Hz), 4.07 (2H, m),1.76 (2H, m),1.55 (3H,
Rf ¼ 0.23 (cyclohexane). IR (film, cmꢀ1):
n 2954, 2929, 2857,
s), 1.49 (3H, s). 13C RMN (100 MHz, CDCl3):
d 145.8, 136.1, 134.5,
1254. 1H RMN (400 MHz, CDCl3):
d 7.42 (1H, m), 7.30 (1H, dt,
3J7e8 ¼ 7.4 Hz, 4J ¼ 2.1 Hz), 7.20 (1H, m), 7.10 (1H, t, 3J ¼ 7.4 Hz), 4.75
(1H, dd, 3J ¼ 5.9 Hz, 3J ¼ 7.8 Hz), 3.75e3.40 (2H, m), 1.91e1.63 (2H,
m), 0.85 (9H, s), 0.80 (9H, s), 0.00 (12H, s). 13C RMN (100 MHz,
130.1, 125.0, 98.3, 96.8, 69.6, 59.4, 33.4, 29.6, 18.6. MS (ESIþ) m/z:
341 ((MþNa)þ, 100), 319 ((MþH)þ, 53).
CDCl3): d 148.0,129.8,129.5,128.9,124.3,122.1, 70.9, 59.1, 43.8, 25.8,
4.1.16. Compound 14b
25.7, 18.1, ꢀ4.7. MS (EI, 70 eV), m/z: 459 ([M]þ., 88), 443 (36),
To a solution of aryl bromide 14a (2.4 g, 5.4 mmol, 1 equiv.) in
dry THF (27 mL), at ꢀ78 ꢁC, was added dropwise a solution of n-
BuLi (2.58 mL, 6.43 mmol, 1.2 equiv.). The reaction mixture was
stirred 30 min and a solution of iodide (3.4 g, 13.5 mmol, 2.5 equiv.)
in dry THF (11 mL) was added dropwise. The reaction mixture was
stirred for 2 h at ꢀ78 ꢁC and for a night at r.t. After hydrolysis by
addition of a saturated solution of Na2S2O3, the aqueous phase was
extracted with AcOEt. The organic layer was washed with a solution
of saturated NaCl, dried over Na2SO4, and evaporated. The residue
was purified by flash chromatography (cyclohexane/AcOEt: 98/2)
to give the compound 14b [2.2 mg, 0.83 mmol, 83%, yellow solid].
Rf ¼ 0.7 (cyclohexane/AcOEt: 95/5). M.p. ¼ 36e37 ꢁC. IR (film,
205(35), 163 (35), 149 (100), 73 (46).
4.1.13. Compound 13a
To a solution of aryl bromide 19 (700 mg, 1.52 mmol, 1 equiv.) in
dry THF (10 mL), at ꢀ78 ꢁC, was added dropwise a solution of n-BuLi
ꢀ
(1.1 mL, 1.82 mmol, 1.2 eq.). The yellow mixture was stirred
30 min and a solution of iodide (967 mg, 3.8 mmol, 2.5 equiv.) in
dry THF (6 mL) was added dropwise. The reaction mixture was
stirred for 2 h at ꢀ78 ꢁC and for a night at r.t. After hydrolysis by
addition of a saturated solution of Na2S2O3, the aqueous phase was
extracted with AcOEt. The organic layer was washed with a solution
of saturated NaCl, dried over Na2SO4, and evaporated. The residue
was purified by flash chromatography (cyclohexane/CH2Cl2: 95/51)
to give the compound 13a [585 mg, 1.15 mmol, 76%, pale yellow oil].
cmꢀ1):
n 2954, 2929, 2885, 2856, 1471, 1254, 1130, 1068, 833, 814,
774. 1H RMN (400 MHz, CD3COCD3):
d 7.84 (1H, bs), 7.64 (1H, dd,
3J ¼ 8.1 Hz, 4J ¼ 1.8 Hz), 7.24 (1H, d, 3J ¼ 8.1 Hz), 4.81 (2H, s), 4.77
Rf ¼ 0.42 (cyclohexane/CH2Cl2: 90/10). IR (film, cmꢀ1):
n 2953,
(2H, s), 0.97 (9H, s), 0.95 (9H, s), 0.14 (6H, s), 0.12 (6H, s). 13C RMN
2928, 2885, 2857, 1471, 1253, 1089. 1H RMN (400 MHz, CDCl3):
(100 MHz, CD3COCD3):
d 140.9, 138.0, 135.6, 135.0, 128.5, 91.8, 61.8,
d
7.62 (1H, t, 4J ¼ 1.2 Hz), 7.52 (1H, dt, 3J ¼ 7.7 Hz, 4J ¼ 1.2 Hz), 7.21
61.5, 25.3, 17.8, ꢀ4.1. MS (ESIþ) m/z: 515.1 ((MþNa)þ, 100), 388.1
(1H, dm, 3J ¼ 7.7 Hz), 6.99 (1H, t, 3J ¼ 7.7 Hz), 4.75 (1H, dd,
3J ¼ 5.77 Hz, 3J ¼ 7.5 Hz), 3.76e3.41 (2H, m), 1.95e1.63 (2H, m), 0.87
(9H, s), 0.83 (9H, s), 0.00 (6H, s), ꢀ0.02 (3H, s), ꢀ0.18 (3H, s). 13C
(41).
RMN (100 MHz, CDCl3):
d
148.0, 135.8, 134.9, 129.7, 124.9, 93.9, 70.8,
4.1.17. Compound 15
59.1, 43.8, 25.8, 25.7, 18.1, ꢀ4.7. MS (ESIþ) m/z: 529 ((MþNa)þ, 100),
To a solution of phenol 25 (400 mg, 1.05 mmol, 1 equiv.) in dry
483 (18), 259 (40), 213 (5).
CH2Cl2 at 0 ꢁC, were added dropwise pyridine (835
mL, 10.5 mmol,
10 equiv.) triflic anhydride (195
mL, 1.15 mmol, 1.1 equiv.). The
4.1.14. Compound 13b
mixture was stirred for 2 h at 0 ꢁC, 1 h at t.a. and was hydrolyzed
with a saturated solution of ammonium chloride. The mixture was
extracted with AcOEt, washed with a solution of saturated NaCl,
dried over Na2SO4, and evaporated. The residue was purified by
flash chromatography on silica gel (cyclohexane/AcOEt: 97/3) to
give compound 15 [480 mg, 0.93 mmol, 89%, colorless oil].
To a solution of diol 20 (1.2 g, 5.2 mmol, 1 equiv.) in dry CH2Cl2
were added Amberlyst 15® (150 mg) and dimethoxypropane
(1.28 mL; 10 mmol; 2 equiv.). The reaction mixture was stirred for a
night at r.t., filtered over a pad of silica and solvent was remove by
evaporation in vacuo. The residue was purified by flash chroma-
tography (cyclohexane/AcOEt: 9/1) to give the compound 13b
[907 mg, 3.3 mmol, 63%, translucent oil].
Rf ¼ 0.86 (cyclohexane/AcOEt: 95/5). IR (film, cmꢀ1):
n 2955,
2931, 2858,1461,1423,1252,1212,1141,1067, 915, 833, 775. 1H RMN
Rf ¼ 0.17 (cyclohexane/AcOEt: 9/1). IR (film, cmꢀ1):
n
3064, 2991,
(400 MHz, CD3COCD3):
d
7.72 (1H, d, 3J ¼ 7.8 Hz), 7.54 (1H, t,
2953, 2869, 2717, 2017, 1596, 1570, 1476, 1424, 1377, 1196, 1161,
3J ¼ 7.8 Hz), 7.31 (1H, d, 3J ¼ 7.8 Hz), 5.04 (2H, s), 4.88 (2H, s), 0.98
1099, 969, 844, 781, 696. 1H RMN (400 MHz, CD3COCD3):
d
7.71 (1H,
(9H, s), 0.92 (9H, s), 0.15 (12H, s). 13C RMN (100 MHz, CD3COCD3):
t, 4J ¼ 1.8 Hz), 7.63 (1H, dt, 3J ¼ 7.6 Hz, 4J ¼ 1.8 Hz), 7.34 (1H, dm,
3J ¼ 7.6 Hz), 7.31 (1H, t, 3J ¼ 7.6 Hz), 5.22 (1H, dd, 3J ¼ 3.6 Hz,
3J ¼ 11.2 Hz), 4.32 (1H, m), 4.03 (1H, m), 1.91 (2H, m), 1.73 (3H, s),
d 147.3, 145.4, 130.5, 127.5, 122.6, 120.5, 62.4, 56.8, 26.3, 26.1,
17.9, ꢀ5.4, ꢀ5.2. 19F RMN (CD3COCD3):
d
104.4. MS (ESIþ) m/z: 537.2
((MþNa)þ, 100).

E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
389
4.1.18. Compound 22
solution of t-BuLi in pentane (1.45 mL, 2.2 mmol, 3.7 equiv.). The
mixture was stirred for 15 min and 6 mL of a solution of zinc
dibromide in dry THF (294 mg, 1.31 mmol, 2.2 equiv.) were added
dropwise. The mixture is then stirred for 1 h 30 min at ꢀ10 ꢁC. In a
second flask, a solution of 14a (300 mg, 0.59 mmol, 1 equiv.) and
tetrakis (triphenylphosphine) palladium (34 mg, 0.03 mmol,
0.05 equiv.) in 6 mL of dry THF was stirred for 15 min and was
added to the mixture at ꢀ78 ꢁC. The mixture was then stirred for a
night at r.t. and was hydrolyzed by addition of a saturated solution
of ammonium chloride. The mixture was extracted with CH2Cl2,
washed with a saturated solution of NaCl, dried over Na2SO4, and
evaporated. The residue was purified by flash chromatography on
silica gel (cyclohexane/CH2Cl2: 95/5) to give the compound 26a
[310 mg, 0.48 mmol, 82%, colorless oil].
To a suspension of LiAlH4 (1.85 g, 0.049 mmol, 4 equiv.) in dry
THF (70 mL) at ꢀ78 ꢁC, was added dropwise, a solution of 4-
Hydroxisoben-zofuran-1,3-dione (2 g, 12 mmol, 1 equiv.) in dry
THF (18 mL). The reaction mixture was stirred 1 h at ꢀ78 ꢁC, 2 h at
r.t., and a night under reflux and was hydrolyzed with HCl 1 M). The
mixture was stirred for a night at r.t. After hydrolysis, the mixture
was extracted with AcOEt, washed with a solution of saturated
NaCl, dried over Na2SO4, and evaporated. The solid was recrystal-
lized in AcOEt to give the compound 22 [1.6 g, 0.01 mmol, 86%,
white crystals].
Rf ¼ 0.31 (cyclohexane/CH2Cl2: 9/1). m.p. (AcOEt) ¼ 82e84 ꢁC. IR
(film, cmꢀ1):
n 3535, 3261, 3082, 2937, 2886, 1588, 1467, 1277, 1165,
980, 961, 786. 1H RMN (400 MHz, CD3COCD3):
d 8.65 (1H, bs), 7.07
(1H, t, 3J ¼ 7.8 Hz), 6.85 (1H, dd, 3J ¼ 6.5 Hz, 4J ¼ 1.1 Hz), 6.78 (1H, dd,
Rf ¼ 0.28 (cyclohexane/CH2Cl2: 95/5). IR (film, cmꢀ1):
n 2953,
3J ¼ 8.1 Hz, 4J ¼ 1.1 Hz), 4.88 (2H, s), 4.64 (2H, s). 13C RMN (100 MHz,
2929, 2858, 2360, 2343, 1971, 1715, 1605, 1464, 1438, 1257, 1087,
CD3COCD3):
d
153.8, 141.2, 127.9, 123.3, 119.7, 115.1, 62.5, 56.8. MS
1027, 837, 724, 264. 1H RMN (400 MHz, CD3COCD3):
d 7.24 (1H, t,
(ESIþ) m/z: 177.1 ((MþNa)þ, 100).
3J ¼ 7.7 Hz), 7.14 (1H, m), 7.11 (1H, d, 3J ¼ 7.7 Hz), 7.06 (1H, d,
3J ¼ 7.7 Hz), 6.07 (1H, s), 4.82 (1H, dd, 3J ¼ 4.7 Hz, 3J ¼ 7.9 Hz), 3.73
(1H, m), 3.58 (1H, m), 2.89 (1H, dd, 3J ¼ 6.7 Hz, 3J ¼ 7 Hz), 2.10 (1H,
m), 2.05 (1H, m), 1.78 (2H, m), 1.74 (1H, m), 1.53 (1H, m), 1.68e1.51
(4H, m), 1.41 (2H, m), 1.35 (1H, m), 1.34 (1H, m), 1.33 (2H, m), 1.16
(2H, m), 1.15 (2H, m), 1.04 (1H, m), 0.96 (3H, d, 3J ¼ 6.2 Hz),
0.92e0.88 (6H, d, 3J ¼ 6.5 Hz), 0.92e0.88 (18H, s), 0.65 (3H, s), 0.04
4.1.19. Compound 23
To a solution of phenol 22 (800 mg, 5.19 mmol, 1 equiv.) in
acetone (50 mL) were added K2CO3 (1.43 g, 10.4 mmol, 2 equiv.),
and KI (86 mg, 0.5 mmol, 0.1 equiv.). The reaction mixture was
ꢀ
heated to reflux and allyl bromide (545 mL, 6.2 mmol, 1.2 eq.) was
added dropwise. The reaction mixture was stirred for 3 h at 60 ꢁC
and was hydrolyzed. The mixture was extracted with EtO2, washed
with a solution of saturated NaCl, dried over Na2SO4, and evapo-
rated. The residue was purified by flash chromatography on silica
gel (cyclohexane/AcOEt: 2/8) to give compound 23 [715 mg,
3.68 mmol, 71%, white crystals].
(12H, s). 13C RMN (100 MHz, CD3COCD3):
d 145.2, 142.7, 138.1,
127.53, 127.4, 126.4, 123.2, 120.8, 71.7, 59.5, 56.6, 56.1, 45.7, 43.9,
40.5, 39.4, 36.1, 36.0, 29.5, 27.9, 27.6, 25.8, 25.7, 23.8, 23.5, 22.7, 22.4,
22.3,18.8,18.1,11.9, ꢀ4.7. MS (ESIþ) m/z: 663 ((MþNa)þ, 5), 557 (13),
507 (96), 377 (90), 279 (100).
Rf ¼ 0.37 (cyclohexane/AcOEt: 2/8). m.p. (AcOEt) ¼ 100e102 ꢁC.
4.1.22. Compound 26c
IR (film, cmꢀ1):
n
3274, 3010, 2928, 2871, 1581, 1459, 1423, 1267,
To a suspension of vinyl bromide 5 (120 mg, 0.25 mmol,1 equiv.)
1256, 1075, 993, 781, 733, 660. 1H RMN (400 MHz, CD3COCD3):
in dry THF (3 mL) at ꢀ78 ꢁC, was added dropwise a solution of t-
d
7.04 (1H, t, 3J ¼ 8.2 Hz), 6.75 (1H, dd, 3J ¼ 8.2 Hz, 4J ¼ 1.1 Hz), 6.68
BuLi in pentane (315 mL, 0.53 mmol, 2.1 equiv.). The mixture was
(1H, dd, 3J ¼ 8.2 Hz, 4J ¼ 1.1 Hz), 5.89 (1H, m), 5.21 (1H, dq,
3J ¼ 17.3 Hz, 4J ¼ 1.5 Hz, 2J ¼ 1.6 Hz), 5.10 (1H, dq, 3J ¼ 10.5 Hz,
4J ¼ 1.5 Hz, 2J ¼ 1.6 Hz), 4.62 (2H, s), 4.46 (2H, s), 4.37 (2H, dt,
stirred for 15 min and 1.5 mL of a solution of zinc dibromide in dry
THF (86 mg, 0.38 mmol, 2.1 equiv.) was added dropwise. The
mixture is then stirred for 1 h 30 at ꢀ10 ꢁC. In a second flask, a
solution of 13c (121 mg, 0.38 mmol, 1.5 equiv.) and tetrakis (tri-
phenylphosphine) palladium (29 mg, 0.025 mmol, 0.1 equiv.) in
2 mL of dry THF was stirred for 15 min and was added to the
mixture at ꢀ78 ꢁC. The mixture was then stirred for a night at r.t.
and was hydrolyzed by addition of a saturated solution of ammo-
nium chloride. The mixture was extracted with CH2Cl2, washed
with a saturated solution of NaCl, dried over Na2SO4, and evapo-
rated. The residue was purified by flash chromatography on silica
gel (cyclohexane/AcOEt: 98/2) to give the compound 26c [89 mg,
0.15 mmol, 61%, colorless oil].
3J ¼ 5.1 Hz, 4J ¼ 1.5 Hz). 13C RMN (100 MHz, CD3COCD3):
d 152.2,
141.2, 133.1, 128.9, 128.3, 121.9, 117.4, 112.2, 69.3, 63.7, 56.0. MS
(ESIþ) m/z: 217.1 ((MþNa)þ, 100).
4.1.20. Compound 24
To a solution of diol 23 (400 mg, 2.1 mmol, 1 equiv.) in dry
CH2Cl2 (10 mL) were added imidazole (1.1 g, 16.8 mmol, 8 equiv.),
DMAP (30 mg, 0.2 mmol, 0.1 equiv.) and tert-butyldimethylsilyl
chloride (1.24 g, 8.4 mmol 4 equiv.). The reaction mixture was
stirred at r.t. for 24 h and was hydrolyzed. The mixture was
extracted with CH2Cl2, washed with H2O, dried over Na2SO4, and
evaporated. The residue was purified by flash chromatography on
silica gel (cyclohexane/AcOEt: 95/5) to give the compound 24
[800 mg, 1.89 mmol, 92%, colorless oil].
Rf
¼
0.52 (cyclohexane/AcOEt: 9/1). 1H RMN (400 MHz,
CD3COCD3):
d
7.14 (1H, t, 3J ¼ 7.4 Hz), 7.10 (1H, s), 7.04 (1H, d,
3J ¼ 7.4 Hz), 6.97 (1H, d, 3J ¼ 7.4 Hz), 5.97 (1H, s), 4.82 (1H, dd,
3J ¼ 3.2 Hz, 3J ¼ 8.1 Hz), 4.0 (1H, m), 3.7 (1H, m), 2.8 (1H, d,
3J ¼ 14.0 Hz), 2.0e1.0 (19H, m), 1.51 (1H, m), 1.39 (3H, s), 1.25 (3H, s),
1.10 (6H, s), 0.87 (3H, d, 3J ¼ 6.2 Hz), 0.85 (9H, t, 3J ¼ 7.3 Hz), 0.55
(3H, s), 0.49 (6H, q, 3J ¼ 7.3 Hz). 13C RMN (100 MHz, CD3COCD3):
Rf ¼ 0.73 (cyclohexane/AcOEt: 9/1). IR (film, cmꢀ1):
n 2954,
2929, 2857, 1588, 1471, 1253, 1055, 1005, 832, 773. 1H RMN
(400 MHz, CD3COCD3):
d
7.05 (1H, t, 3J ¼ 8.1 Hz), 6.79 (1H, dd,
3J ¼ 8.1 Hz, 4J6e4 ¼ 1.0 Hz), 6.72 (1H, dd, 3J ¼ 8.1 Hz, 4J ¼ 1.0 Hz), 5.93
(1H, m), 5.29 (1H, dq, 3J ¼ 17.0 Hz, 4J ¼ 1.8 Hz, 2J ¼ 1.4 Hz), 5.05 (1H,
dq, 3J ¼ 10.5 Hz, 4J ¼ 1.8 Hz, 2J ¼ 1.4 Hz), 4.78 (2H, s), 4.68 (2H, s),
4.39 (2H, dt, 3J ¼ 5.1 Hz, 4J ¼ 1.8 Hz), 1.21 (9H, s), 0.93 (9H, s), 0.10
d 142.9, 142.4, 138.2, 127.6, 127.5, 126.2, 123.7, 120.8, 98.1, 73.2, 70.7,
59.5, 56.5, 55.9, 45.5, 45.3, 40.3, 36.3, 35.9, 33.5, 29.7, 29.5, 29.2,
27.5, 27.4, 23.3, 22.1, 20.5, 18.5, 18.3, 11.4, 6.5. MS (ESIþ) m/z: 605.4
((MþNa)þ, 100), 563.4 (37).
(6H, s), 0.08 (6H, s). 13C RMN (100 MHz, CD3COCD3):
d 154.8, 139.7,
133.8, 128,2,124.7, 118.8,116.1,110.8, 68.9, 62.1, 55.2, 25.3,17.9, ꢀ3.8.
4.1.23. Compound 27b
MS (ESIþ) m/z: 445.2 ((MþNa)þ, 100).
To a suspension of vinyl bromide 12b (300 mg, 0.69 mmol,
1 equiv.) in dry THF (6 mL) at ꢀ78 ꢁC, was added dropwise a so-
4.1.21. Compound 26a
lution of t-BuLi in pentane (84 mL, 1.44 mmol, 2.1 equiv.). The
To a suspension of vinyl bromide 4 (304 mg, 0.89 mmol,
mixture was stirred for 15 min and 5 mL of a solution of zinc
dibromide in dry THF (232 mg, 1.03 mmol, 1.5 equiv.) were added
1.5 equiv.) in dry THF (9 mL) at ꢀ78 ꢁC, was added dropwise a

390
E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
dropwise. The mixture is then stirred for 1 h 30 min at ꢀ10 ꢁC. In a
second flask, a solution of 13c (327 mg, 1.03 mmol, 1.5 equiv.) and
tetrakis (triphenylphosphine) palladium (79 mg, 0.069 mmol,
0.1 equiv.) in 5 mL of dry THF was stirred for 15 min and was added
to the mixture at ꢀ78 ꢁC. The mixture was then stirred for a night at
r.t. and was hydrolyzed by addition of a saturated solution of
ammonium chloride. The mixture was extracted with CH2Cl2,
washed with a saturated solution of NaCl, dried over Na2SO4, and
evaporated. The residue was purified by flash chromatography on
silica gel (cyclohexane/AcOEt: 95/5) to give the compound 27b
[253 mg, 0.46 mmol, 67%, colorless oil].
evaporated. The residue was purified by flash chromatography on
silica gel (cyclohexane/AcOEt: 95/5) to give the compound 29
[300 mg, 0.41 mmol, 91%, translucent oil].
Rf ¼ 0.65 (cyclohexane/AcOEt: 95/5). IR (film, cmꢀ1):
n 2930,
2856, 1651, 1462, 1378, 1361, 1253, 1125, 1074, 986, 835, 775. 1H
RMN (400 MHz, CD3COCD3):
d
7.37 (1H, d, 3J ¼ 8.1 Hz), 7.35 (1H, s),
7.09 (1H, d, 3J ¼ 8.1 Hz), 6.10 (1H, s), 5.16 (1H, m), 4.83 (2H, s), 4.80
(2H, s), 3.88 (1H, m), 3.45 (1H, m), 2.96 (1H, m), 2.17 (1H, m),
2.2e1.2 (12H, m), 2.06 (1H, m), 1.76 (1H, m), 1.67 (1H, m), 1.64 (1H,
m), 1.56 (1H, m), 1.51 (1H, m), 1.43 (6H, s), 1.40 (1H, m), 1.12 (3H, d,
3J ¼ 6.3 Hz), 0.94 (18H, s), 0.68 (3H, s), 0.11 (12H, s). 13C RMN
Rf ¼ 0.36 (cyclohexane/AcOEt:9/1). IR (film, cmꢀ1):
n
2991, 2953,
(100 MHz, CD3COCD3): d 143.1, 139.1, 138.1, 136.7, 128.1, 127.9, 127.5,
2869, 2245, 1566, 1377, 1196, 1161, 1095, 969, 854, 731, 694. 1H RMN
121.8, 96.3, 84.8, 83.5, 71.9, 63.4, 62.9, 56.9, 56.3, 46.5, 41.2, 36.5,
32.8, 30.7, 30.6, 29.1, 28.1, 26.4, 26.3, 24.4, 24.4, 23.1, 19.6, 18.9 (x2),
17.9, 12.5, ꢀ4.3. MS (ESIþ) m/z: 745.6 ((MþNa)þ, 5), 381.3 (100).
(400 MHz, CDCl3):
d
7.27 (1H, t, 3J ¼ 7.5 Hz), 7.19 (1H, s), 7.17 (1H, d,
3J ¼ 7.5 Hz), 7.11 (1H, d, 3J ¼ 7.5 Hz), 6.06 (1H, s), 5.08 (1H, bs), 4.89
(1H, dd, 3J ¼ 2.4 Hz, 3J ¼ 11.6 Hz), 4.1 (1H, m), 3.95 (2H, m), 3.49 (1H,
m), 2.89 (1H, d, 3J ¼ 12,9 Hz), 2.20e1.40 (21H, m), 1.62 (1H, m), 1.56
(3H, s), 1.51 (3H, s), 1.48 (6H, s), 1.09 (3H, d, 3J ¼ 5.4 Hz), 0.64 (3H, s).
4.1.26. Compound 30
To a suspension of vinyl bromide 4 (220 mg, 0.65 mmol,
1.5 equiv.) in dry THF (6 mL) at ꢀ78 ꢁC, was added dropwise a so-
lution of t-BuLi in pentane (1.06 mL, 1.59 mmol, 3.7 equiv.). The
mixture was stirred for 15 min and 4.5 mL of a solution of zinc
dibromide in dry THF (213 mg, 0.95 mmol, 2.2 equiv.) were added
dropwise. The mixture is then stirred for 1 h 30 min at ꢀ10 ꢁC. In a
second flask, a solution of 15a (222 mg, 0.43 mmol, 1 equiv.) and
tetrakis (triphenylphosphine) palladium (25 mg, 0.02 mmol,
0.05 equiv.) in 4.5 mL of dry THF was stirred for 15 min and was
added to the mixture at ꢀ78 ꢁC. The mixture was then stirred for a
night at r.t. and was hydrolyzed by addition of a saturated solution
of ammonium chloride. The mixture was extracted with CH2Cl2,
washed with a saturated solution of NaCl, dried over Na2SO4, and
evaporated. The residue was purified by flash chromatography on
silica gel (cyclohexane/CH2Cl2: 95/5) to give the compound 30
[140 mg, 0.22 mmol, 52%, colorless oil].
13C RMN (100 MHz, CDCl3):
d 142.6, 142.1, 138.5, 128.0, 127.9, 126.4,
123.3, 120.8, 98.6, 96.1, 83.8, 82.8, 71.6, 71.3, 63.3, 60.0, 56.0, 55.5,
45.6, 40.3, 35.7, 33.4, 32.0, 30.9, 30.1, 29.9, 29.4, 27.3, 25.7, 25.3, 23.4,
22.2, 20.6, 19.1 (x2), 12.0.
4.1.24. Compound 28
To a suspension of vinyl bromide 4 (250 mg, 0.73 mmol,
1.5 equiv.) in dry THF (7 mL) at ꢀ78 ꢁC, was added dropwise a so-
lution of t-BuLi in pentane (1.2
mL, 1.8 mmol, 3.7 equiv.). The
mixture was stirred for 15 min and 5 mL of a solution of zinc
dibromide in dry THF (242 mg, 1.07 mmol, 2.2 equiv.) were added
dropwise. The mixture is then stirred for 1 h 30 min at ꢀ10 ꢁC. In a
second flask, a solution of 14b (240 mg, 0.49 mmol, 1 equiv.) and
tetrakis (triphenylphosphine) palladium (56 mg, 0.048 mmol,
0.05 equiv.) in 5 mL of dry THF was stirred for 15 min and was
added to the mixture at ꢀ78 ꢁC. The mixture was then stirred for a
night at r.t. and was hydrolyzed by addition of a saturated solution
of ammonium chloride. The mixture was extracted with CH2Cl2,
washed with a saturated solution of NaCl, dried over Na2SO4, and
evaporated. The residue was purified by flash chromatography on
silica gel (cyclohexane/CH2Cl2: 9/1) to give the compound 28
[280 mg, 0.45 mmol, 91%, colorless oil].
Rf ¼ 0.31 (cyclohexane/CH2Cl2: 95/5). IR (film, cmꢀ1):
n 2952,
2928, 2856, 1463, 1377, 1253, 1126, 1066, 834, 774. 1H RMN
(400 MHz, CDCl3):
d
7.56 (1H, d, 3J ¼ 7.7 Hz), 7.37 (1H, t, 3J ¼ 7.7 Hz),
7.14 (1H, d, 3J ¼ 7.7 Hz), 6.09 (1H, s), 4.58 (2H, s), 4.31 (2H, s), 2.41
(1H, m), 2.12e1.02 (19H, m), 0.82 (9H, s), 0.77 (9H, s), 0.76 (3H, d,
3J ¼ 5.8 Hz), 0.73 (6H, d, 3J ¼ 6.6 Hz), 0.44 (3H, s), 0.01 (6H, s), 0.00
(6H, s). 13C RMN (100 MHz, CDCl3):
d 142.3,138.7,138.4,136.4,130.4,
Rf ¼ 0.31 (cyclohexane/CH2Cl2: 9/1). IR (film, cmꢀ1):
n
2952,
128.3, 127.5, 118.9, 63.8, 59.6, 56.9, 55.8, 46.2, 40.7, 39.3, 36.3, 36.1,
29.9, 27.2, 26.6, 25.8, 23.3, 23.6, 22.9, 22.5, 21.8,18.6,18.3,12.2, ꢀ4.8.
MS (ESIþ) m/z: 649.6 ((MþNa)þ, 100).
2928, 2856, 1653, 1463, 1377, 1253, 1159, 1066, 834, 814, 774. 1H
RMN (400 MHz, CDCl3):
d
7.35 (1H, d, 3J ¼ 7.9 Hz), 7.30 (1H, s), 7.10
(1H, d, 3J ¼ 7.9 Hz), 5.98 (1H, s), 4.67 (2H, s), 4.64 (2H, s), 2.93 (1H,
m), 2.15e1.0 (18H, m), 1.41 (1H, m), 0.96 (18H, s), 0.94 (3H, d,
4.1.27. Compound 31
3J ¼ 6.0 Hz), 0.89 (6H, d, 3J ¼ 6.2 Hz), 0.66 (3H, s), 0.10 (12H, s). 13
C
To a suspension of vinyl bromide 12b (330 mg, 0.75 mmol,
1.5 equiv.) in dry THF (8 mL) at ꢀ78 ꢁC, was added dropwise a so-
lution of t-BuLi in pentane (1.23 mL, 1.85 mmol, 3.7 equiv.). The
mixture was stirred for 15 min and 5 mL of a solution of zinc
dibromide in dry THF (248 mg, 0.95 mmol, 2.2 equiv.) were added
dropwise. The mixture is then stirred for 1 h 30 min at ꢀ10 ꢁC. In a
second flask, a solution of 15 (257 mg, 0.5 mmol, 1 equiv.) and
tetrakis (triphenylphosphine) palladium (58 mg, 0.05 mmol,
0.1 equiv.) in 5 mL of dry THF was stirred for 15 min and was added
to the mixture at ꢀ78 ꢁC. The mixture was then stirred for a night at
r.t. and was hydrolyzed by addition of a saturated solution of
ammonium chloride. The mixture was extracted with AcOEt,
washed with a saturated solution of NaCl, dried over Na2SO4, and
evaporated. The residue was purified by flash chromatography on
silica gel (cyclohexane/AcOEt: 95/5) to give the compound 31
[199 mg, 0.27 mmol, 55%, colorless oil].
RMN (100 MHz, CDCl3):
d 142.7, 137.9, 137.4, 136.4, 127.4, 127.2,
126.5, 120.8, 62.9, 62.8, 56.8, 56.3, 45.9, 40.6, 39.5, 36.2, 36.1, 29.5,
28.0, 27.7, 25.9, 23.6, 23.2, 22.8, 22.6, 22.4, 19.2, 18.9, 11.9, ꢀ5.2. MS
(ESIþ) m/z: 650.2 ((MþNa)þ, 100), 535.1 (27).
4.1.25. Compound 29
To a suspension of vinyl bromide 12b (300 mg, 0.69 mmol,
1.5 equiv.) in dry THF (7 mL) at ꢀ78 ꢁC, was added dropwise a so-
lution of t-BuLi in pentane (1.13 mL, 1.69 mmol, 3.7 equiv.). The
mixture was stirred for 15 min and 5 mL of a solution of zinc
dibromide in dry THF (226 mg, 1 mmol, 2.2 equiv.) were added
dropwise. The mixture is then stirred for 1 h 30 min at ꢀ10 ꢁC. In a
second flask, a solution of 14b (225 mg, 0.46 mmol, 1 equiv.) and
tetrakis (triphenylphosphine) palladium (53 mg, 0.046 mmol,
0.1 equiv.) in 5 mL of dry THF was stirred for 15 min and was added
to the mixture at ꢀ78 ꢁC. The mixture was then stirred for a night at
r.t. and was hydrolyzed by addition of a saturated solution of
ammonium chloride. The mixture was extracted with CH2Cl2,
washed with a saturated solution of NaCl, dried over Na2SO4, and
Rf ¼ 0.39 (cyclohexane/AcOEt: 95/5). 1H RMN (400 MHz,
CD3COCD3):
d
7.55 (1H, d, 3J ¼ 7.8 Hz), 7.41 (1H, t, 3J ¼ 7.8 Hz), 7.19
(1H, d, 3J ¼ 7.8 Hz), 6.11 (1H, s), 5.01 (1H, m), 4.61 (2H, s), 4.33 (2H,
s), 3.75 (1H, m), 3.31 (1H, m), 2.18 (1H, m), 2.2e1.2 (18H, m), 2.07

E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
391
(1H, m), 1.62 (1H, m), 1.34 (6H, s), 1.01 (3H, d, 3J ¼ 6.2 Hz), 0.84 (9H,
s), 0.78 (9H, s), 0.47 (3H, s), 0.02 (12H, s). 13C RMN (100 MHz,
CD3COCD3): 142.3, 138.5, 136.6, 134.8, 130.7, 129.3, 127.9, 121.4, 97.4,
85.2, 84.5, 72.9, 63.9 (x2), 61.9, 57.1, 56.6, 46.7, 41.9, 37.5, 33.8, 32.7,
31.7, 29.1, 27.4, 27.2, 25.6, 23.9, 22.6, 21.9, 20.1, 18, 17.6, 13.3, ꢀ2.8.
MS (ESIþ) m/z: 745.5 ((MþNa)þ, 100), 630.4 (63), 515.3 (25).
chromatography (Cyclohexane/AcOEt: 1/1) to give the compound
34 [92 mg, 0.21 mmol, 80%, amorphous solid].
25
Rf ¼ 0.14 (Cyclohexane/AcOEt: 1/1), [
(film, cmꢀ1):
1240, 1163, 1049, 947, 708. 1H RMN (400 MHz, CDCl3):
a
]
82.6 (c 0.1, CHCl3). IR
D
n
3352, 2944, 2871, 2232, 1723, 1653, 1602, 1433, 1376,
7.25 (1H, t,
d
3J ¼ 7.3 Hz), 7.16 (1H, s), 7.14 (1H, d, 3J ¼ 8.6 Hz), 7.09 (1H, d,
3J ¼ 7.5 Hz), 6.04 (1H, s), 4.89 (1H, dd, 3J ¼ 3.7 Hz, 3J ¼ 12.2 Hz), 3.80
(2H, t, 3J ¼ 4.8 Hz), 2.86 (1H, d, 3J ¼ 12.7 Hz), 2.09 (1H, m), 2.16 (1H,
m), 1.98 (2H, m), 1.93 (1H, m), 1.91 (1H, m), 1.73 (1H, m), 1.59 (2H,
m), 1.58 (1H, m), 1.57 (2H, m), 1.49 (6H, s), 1.41 (1H, m), 1.36 (1H, m),
1.31 (1H, m), 1.07 (3H, d, 3J ¼ 6.5 Hz), 0.62 (3H, s). 13C RMN
4.1.28. Compound 32
To a solution of disilylether 26a (310 mg, 0.48 mmol, 1 equiv.) in
dry THF (20 mL) was added a solution of TBAF in THF (5.81 mL,
5.81 mmol, 12 equiv.). The yellow and translucent reaction mixture
was stirred at room temperature for 24 h. A saturated solution of
sodium bicarbonate was added (20 mL). The aqueous phase was
extracted with AcOEt (x4). The combined organic phase was dried,
filtered, and concentrated in vacuo. The residue was purified by a
flash chromatography (Cyclohexane/AcOEt: 6/4) and HPLC (column
deltapack® C18, CH3CN/H2O 85/15) to give the compound 32
(100 MHz, CDCl3):
d 144.0, 142.8, 138.6, 128.0, 127.9, 126.1, 123.0,
120.8, 86.2, 81.1, 73.9, 65.2, 61.0, 56.0, 55.7, 45.6, 40.4, 40.2, 35.9,
31.7, 29.3, 27.3, 25.6, 23.4, 22.3, 19.1, 12.0. MS (ESIþ) m/z 470.3
((Mþ2Na)þ, 27), 447.3 ((MþNa)þ, 100). Anal. Calcd for [C36H52O4]:
C, 79.20, H, 9.50. Found: C, 75.89, H, 9.45. HPLC: Column Deltapack®
C18, Absorbance: 300 nm, (Eluant:CH3CN/H2O 8/2). Concentration:
10 mg/mL, r.T. ¼ 15.9 min.
[192 mg, 0.46 mmol, 96%, colorless oil].
25
Rf ¼ 0.2 (cyclohexane/AcOEt: 1/1). [
a
]
¼ þ68ꢁ (both enantio-
D
mers, c 0.11, CHCl3). IR (film, cmꢀ1):
n
3368, 2951, 2932, 2869, 1704,
4.1.31. Compound 35
1602, 1466, 1376, 1240, 1048, 707, 649. 1H RMN (400 MHz, CDCl3):
To a solution of disilylether 28 (250 mg, 0.4 mmol, 1 equiv.) in
dry THF (20 mL) was added a solution of TBAF in THF (4.8 mL,
4.8 mmol, 12 equiv.). The yellow and translucent reaction mixture
was stirred at room temperature for 24 h. The crude product was
filtered over a pad of silica (elution with Cyclohexane/EtOAc 1/1).
After concentration in vacuo, the residue was purified by a first
flash chromatography (Cyclohexane/AcOEt: 1/1) and a second one
(CH2Cl2/AcOEt: 8/2) to give the diol 35 [120 mg, 0.3 mmol, 75%,
d
7.25 (1H, t, 3J ¼ 7.6 Hz), 7.14 (1H, s), 7.11 (1H, d, 3J7e6 ¼ 7.6 Hz), 7.06
3
(1H, d, J5e6 ¼ 7.6 Hz), 6.05 (1H, s), 4.88 (1H, dd, 3J ¼ 3.2 Hz,
3J ¼ 8.4 Hz), 3.81 (2H, t, 3J ¼ 4.7 Hz), 2.88 (1H, d, 3J ¼ 12.5 Hz), 2.11
(1H, m), 2.0 (1H, m), 1.94 (2H, m), 1.76 (1H, m), 1.61 (2H, m), 1.55
(1H, m), 1.41 (2H, m), 1.38 (2H, m), 1.36 (1H, m), 1.35 (1H, m), 1.33
(2H, m), 1.17 (2H, m), 1.12 (2H, m), 1.04 (1H, m), 0.94 (3H, d,
3J ¼ 6.1 Hz), 0.87 (6H, d, 3J ¼ 6.4 Hz), 0.63 (3H, s). 13C RMN
(100 MHz, CDCl3):
d
143.9, 143.3, 138.7, 128.1, 128.1, 126.2, 122.9,
amorphous solid].
D
120.5, 74.2, 61.3, 56.6, 56.11, 45.7, 40.4 (x2), 39.4, 36.1, 36.0, 29.4,
27.9, 27.5, 23.8, 23.6, 22.7, 22.5, 22.3, 18.8, 11.9. MS (ESIþ) m/z 431
((MþNH4)þ, 30), 391 (100), 242 (18). Anal. Calcd for [C28H44O2]: C,
81.55, H, 10.68. Found: C, 81.37, H, 10.53. HPLC: Column Deltapack®
C18, Absorbance: 300 nm, (Eluant: CH3CN/H2O 85/15). Concentra-
tion: 10 mg/mL, r.T. ¼ 17.39 min.
Rf ¼ 0.2 (cyclohexane/AcOEt 1/1). [
a
]
25
¼ þ12.3ꢁ (c ¼ 0.31
CHCl3). IR (film, cmꢀ1):
n
2953, 2929, 2857, 2360, 2255, 2176, 2156,
2071, 2010, 1994, 1496, 1405, 1255, 1214, 1068, 837, 809, 730. 1H
RMN (400 MHz, CDCl3):
d
7.26 (1H, d, 3J ¼ 7.3 Hz), 7.19 (1H, s),7.16
(1H, d, 3J ¼ 7.3 Hz), 6.06 (1H, s), 4.68 (2H, s), 4.67 (2H, s), 2.89 (1H,
m), 2.12 (1H, m), 2.06 (1H, m), 1.94 (2H, m), 1.76 (1H, m), 1.65 (2H,
m), 1.61 (2H, m), 1.59 (2H, m), 1.41 (1H, m), 1.39 (2H, m), 1.36 (1H,
m), 1.34 (1H, m), 1.33 (1H, m), 1.27 (2H, m), 0.96 (3H, d, 3J ¼ 6.1 Hz),
0.90 (6H, d, 3J ¼ 6.6 Hz), 0.65 (3H, s). 13C RMN (100 MHz, CDCl3):
4.1.29. Compound 33
To a solution of 26c (80 mg, 0.14 mmol, 1 equiv.) in dry MeOH
(5 mL) was added resin Dowex 50WX2 (200 mg). The reaction
mixture was heated at 60 ꢁC. After being stirred for 2 h, the crude
product was filtered over a pad of silica (elution with EtOAc). After
concentration in vacuo, the residue was purified by flash chroma-
tography (Cyclohexane/AcOEt: 1/1) to give the compound 33
[48 mg, 0.11 mmol, 82%, amorphous solid].
d
143.7, 138.9, 138.7, 136.6, 130.2, 129.4, 128.7, 119.9, 64.2, 63.7, 56.6;
56.1, 45.7, 40.3, 39.4, 36.0, 35.9, 29.4, 27.9, 27.5, 23.8, 23.5, 22.7, 22.4,
22.3, 18.8, 11.9. MS (ESIþ) m/z 421.3 ((MþNa)þ, 100). Anal. Calcd for
[C27H42O2]: C, 81.35, H, 10.62. Found: C, 81.31, H, 10.58. HPLC: Col-
umn Deltapack® C18, Absorbance: 300 nm, (Eluant: CH3CN/H2O:
85/15). Concentration: 10 mg/mL, r.T. ¼ 15.18 min.
Rf ¼ 0.14 (Cyclohexane/AcOEt 1/1). [
a
]
25 þ53.1 (c 0.05, CHCl3). 1H
D
RMN (400 MHz, CDCl3):
d
7.29 (1H, t, 3J ¼ 7.6 Hz), 7.20 (1H, s), 7.18
4.1.32. Compound 36
(1H, d, 3J ¼ 7.6 Hz), 7.13 (1H, d, 3J ¼ 7.5 Hz), 6.07 (1H, s), 4.93 (1H, dd,
3J ¼ 3.6 Hz, 3J ¼ 8.2 Hz), 3.85 (2H, t, 3J ¼ 3.8 Hz), 2.89 (1H, d,
3J ¼ 12.4 Hz), 2.10 (1H, m), 2.08 (1H, m), 2.0 (2H, m), 1.98 (2H, m),
1.78 (1H, m), 1.59 (2H, m), 1.58 (2H, m), 1.46 (1H, m), 1.43 (2H, m),
1.41 (1H, m), 1.38 (1H, m), 1.25 (2H, m), 1.23 (6H, s), 1.10 (2H, m),
0.97 (3H, d, 3J ¼ 6.3 Hz), 0.65 (3H, s). 13C RMN (100 MHz, CDCl3):
To a solution of 29 (300 mg, 0.41 mmol, 1 equiv.) in dry MeOH
(19 mL) was added resin Dowex 50WX2 (770 mg). The reaction
mixture was heated at 60 ꢁC. After being stirred for 2 h, the crude
product was filtered over a pad of silica (elution with EtOAc). After
concentration in vacuo, the residue was purified by flash chroma-
tography (Cyclohexane/AcOEt: 1/1) to give the compound 36
d
144.0, 143.2, 138.9, 128.1, 128.0, 126.2, 123.0, 120.6, 74.3, 71.2, 61.4,
[136 mg, 0.33 mmol, 81%, amorphous solid].
25
56.6, 56.2, 45.8, 44.4, 40.4, 36.4, 36.1, 30.1, 29.5, 29.3, 29.1, 27.6, 26.8,
23.6, 22.4, 18.8, 11.9. MS (ESIþ) m/z: 451.3 ((MþNa)þ, 100). Anal.
Calcd for [C36H52O4]: C, 78.46, H, 10.35. Found: C, 78.35, H 10.26.
HPLC: Column Deltapack® C18, Absorbance: 300 nm,
(Eluant:CH3CN/H2O 8/2). Concentration: 10 mg/mL, r.T. ¼ 16.8 min.
Rf ¼ 0.2 (cyclohexane/AcOEt: 1/1). [
a
]
D
¼ þ33.1ꢁ (c 0.13, MeOH).
IR (film, cmꢀ1): 3317, 2930, 2870, 2234, 1739, 1724,1447, 1375, 1239,
1163, 1013, 947, 858. 1H RMN (400 MHz, CDCl3):
d 7.32 (1H, d,
3J ¼ 7.9 Hz), 7.25 (1H, s), 7.13 (1H, d, 3J ¼ 7.9 Hz), 6.08 (1H, s), 4.67
(4H, bs), 2.92 (1H, d, 3J ¼ 12.3 Hz), 2.23 (1H, m), 2.14 (1H, m), 2.05
(2H, m), 1.97 (1H, m), 1.76 (1H, m), 1.61 (2H, m), 1.57 (1H, m), 1.56
(2H, m), 1.49 (1H, m), 1.43 (6H, s), 1.39 (1H, m), 1.35 (1H, m), 1.10
4.1.30. Compound 34
To a solution of 27b (150 mg, 0.27 mmol, 1 equiv.) in dry MeOH
(10 mL) was added resin Dowex 50WX2 (400 mg). The reaction
mixture was heated at 60 ꢁC. After being stirred for 2 h, the crude
product was filtered over a pad of silica (elution with EtOAc). After
concentration in vacuo, the residue was purified by flash
(3H, d, 3J ¼ 6.3 Hz), 0.63 (3H, s). 13C RMN (100 MHz, CDCl3):
d 143.2,
140.5, 138.3 (x2), 129.5, 128.6, 128.4, 121.6, 88.2, 80.2, 64.8, 63.2,
62.9, 56.8, 56.4, 46.4, 41.1, 36.8, 32.5 (x2), 30.1, 28.1, 26.2, 24.2, 23.1,
19.6, 12.5. MS (ESIþ) m/z 433.3 ((MþNa)þ, 100). Anal. Calcd for
[C27H38O3]: C, 78.98, H, 9.33. Found: C, 78.89, H, 9.22.

392
E. Thomas et al. / European Journal of Medicinal Chemistry 86 (2014) 381e393
4.1.33. Compound 37
4.2.2. Induction of HL-60 cell differentiation
To a solution of disilylether 30 (100 mg, 0.16 mmol, 1 equiv.) in
dry THF (5 mL) was added a solution of TBAF in THF (1.92 mL,
1.92 mmol, 12 equiv.). The yellow and translucent reaction mixture
was stirred at room temperature for 24 h. The crude product was
filtered over a pad of silica (elution with Cyclohexane/EtOAc 1/1).
After concentration in vacuo, the residue was purified by a first
flash chromatography (Cyclohexane/AcOEt: 1/1) and a second one
(CH2Cl2/AcOEt:8/2) to give the diol 37 [48 mg, 0.12 mmol, 76%,
amorphous solid].
The analogues compounds were incubated with HL-60 cells at
37 ꢁC for 144 h. Cells were then incubated for 4 h with Wst-1 re-
agent and the absorbency was measured in each well at 450 nM
and 620 nM, following the Marcinkowska procedure[53]. Two in-
dependent experiments were performed and the results are pre-
sented as the concentration of test substances allowing a 50%
inhibition of proliferation (IC50). The experiments were carried out
in duplicate. All assays were performed by CELLIS Pharma in the
study number CP-2004061.1.
Rf ¼ 0.22 (cyclohexane/AcOEt:1/1). IR (film, cmꢀ1):
n 3317, 2949,
2928, 2868, 1656, 1590, 1465, 1377, 1330, 1188, 997, 799, 768, 735.
Acknowledgments
D
[
a]
¼ þ78.2ꢁ (c ¼ 0,31 CHCl3). 1H RMN (400 MHz, CDCl3):
d 7.23
25
(2H, m), 7.14 (1H, d, 3J ¼ 6.8 Hz), 6.21 (1H, s), 4.77 (2H, s, H), 4.73
(2H, s), 3.16 (2H, bs), 2.48 (1H, m), 2.13 (1H, m), 2.05 (1H, m), 1.97
(2H, m), 1.66 (1H, m), 1.64 (2H, m), 1.60 (2H, m), 1.57 (2H, m), 1.40
(1H, m), 1.38 (2H, m), 1.36 (1H, m), 1.35 (1H, m), 1.33 (1H, m), 1.25
(2H, m), 0.97 (3H, d, 3J ¼ 5.3 Hz), 0.90 (6H, d, 3J ¼ 6.3 Hz), 0.69 (3H,
Dr. C. Harpey, Dr. A. Le Ridant and Les Laboratoires Servier are
gratefully acknowledged for financial support and for a doctoral
fellowship to E. Thomas.
s). 13C RMN (100 MHz, CDCl3):
d 144.2, 139.9, 139.0, 137.4, 130.5,
Appendix A. Supplementary data
128.1, 127.8, 118.7, 64.7, 59.9, 56.7, 55.9, 45.8, 40.4, 39.5, 36.1, 36.0,
29.7, 27.9, 27.6, 23.9, 23.5, 22.8, 22.5, 22.4, 18.8, 12.0. MS (ESIþ) m/z
451.3 ((MþNa)þ, 100). Anal. Calcd for [C36H52O4]: C, 78.46, H, 10.35.
Found: C, 78.35, H 10.26. HPLC: Column Deltapack® C18, Absor-
bance: 300 nm, (CH3CN/H2O: 85/15). Concentration: 10 mg/mL,
r.T. ¼ 16.32 min.
Supplementary data related to this article can be found at http://
dx.doi.org/10.1016/j.ejmech.2014.07.037.
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n 3312, 2933,
2860, 2231, 1725, 1443, 1375, 1236, 1165, 1013, 947, 756. 1H RMN
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7.36 (1H, d, 3J ¼ 7.4 Hz), 7.19 (1H, t, 3J ¼ 7.4 Hz),
7.15 (1H, d, 3J ¼ 7.4 Hz), 6.12 (1H, s), 4.69 (2H, s), 4.67 (2H, s), 2.43
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d 143.9, 139.7,
138.8, 137.3, 130.4, 129.0, 128.1, 121.2, 88.6, 88.2, 64.6, 63.4, 63.2,
56.1, 55.6, 45.6, 40.1, 35.8, 31.7 (x2), 29.5, 27.3, 25.6, 23.3, 22.2, 19.1,
12.0. MS (ESIþ) m/z 433.2 ((MþNa)þ, 100). Anal. Calcd for
[C27H38O3]: C, 78.98, H, 9.33. Found: C, 78.52, H, 9.15.
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