Extending Cross Metathesis to Identify Selective HDAC Inhibitors: Synthesis, Biological Activities, and Modeling

Article abstract of DOI:10.1021/acsmedchemlett.8b00440

Dissymmetric cross metathesis of alkenes as a convergent and general synthetic strategy allowed for the preparation of a new small series of human histone deacetylases (HDAC) inhibitors. Alkenes bearing Boc-protected hydroxamic acid and benzamide and trityl-protected thiols were used to provide the zinc binding groups and were reacted with alkenes bearing aromatic cap groups. One compound was identified as a selective HDAC6 inhibitor lead. Additional biological evaluation in cancer cell lines demonstrated its ability to stimulate the expression of the epithelial marker E-cadherin and tumor suppressor genes like SEMA3F and p21, suggesting a potential use of this compound for lung cancer treatment. Molecular docking on all 11 HDAC isoforms was used to rationalize the observed biological results.

Full text of DOI:10.1021/acsmedchemlett.8b00440

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Letter
Extending cross metathesis to identify selective HDAC
inhibitors: synthesis, biological activities and modelling
Samuel Bouchet, Camille Linot, Dusan Ruzic, Danica D. Agbaba, Benoit Fouchaq,
Joëlle Roche, Katarina Nikolic, Christophe Blanquart, and Philippe Bertrand
ACS Med. Chem. Lett., Just Accepted Manuscript • DOI: 10.1021/acsmedchemlett.8b00440 • Publication Date (Web): 09 May 2019
Downloaded from http://pubs.acs.org on May 9, 2019
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Extending cross metathesis to identify selective HDAC inhibitors:
synthesis, biological activities and modelling.
Samuel Bouchet1, Camille Linot2, Dusan Ruzic3, Danica Agbaba3, Benoit Fouchaq4,5, Joëlle Roche5,6,
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Katarina Nikolic3, Christophe Blanquart2,5, Philippe Bertrand1,5*.
1 Institut de Chimie des Milieux et Matériaux de Poitiers, UMR CNRS 7285, 4 rue Michel Brunet, TSA 51106, B28, 86073,
Poitiers cedex 09, France.
2 CRCINA, INSERM, Université d’Angers, Université de Nantes, Nantes, France.
3 Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11000
Belgrade, Serbia.
4 Eurofins-Cerep, Le Bois l’Evêque, 86600 Celle – L’Evescault, France.
5 Réseau Epigénétique du Cancéropôle Grand Ouest. France.
6 Laboratoire EBI, University of Poitiers, UMR CNRS 7267, F-86073 Poitiers, France.
KEYWORDS: Cross metathesis, Histone deacetylases, lung cancer, epigenetics, molecular modeling.
ABSTRACT: Dissymmetric cross metathesis of alkenes as a convergent and general synthetic strategy allowed for the preparation
of a new small series of HDAC inhibitors. Alkenes bearing BOC-protected hydroxamic acid and benzamide and trityl-protected thiols
were used to provide the zinc binding groups and were reacted with alkenes bearing aromatic cap groups. One compound was
identified as a selective HDAC6 inhibitor lead. Additional biological evaluation in cancer cell lines demonstrated its ability to
stimulate the expression of the epithelial marker E-cadherin, and tumor suppressor genes like SEMA3F and p21, suggesting a
potential use of this compound for lung cancer treatment. Molecular docking on all eleven HDAC isoforms was used to rationalize
the observed biological results.
deacetylases. The over-expression of HDACs in cancer cell
Human histone deacetylases (HDAC) and their inhibitors
lines is correlated with the repressed expression of tumour
(HDACi) are part of the therapies used to treat human cancers,
suppressor genes (TSG),8,9,10 and HDACi are evaluated alone or
in combination.11
with four HDACi approved by FDA: SAHA 11 (suberoyl
anilide hydroxamic acid, Chart 1, vorinostat) for cutaneous T-
cell lymphomas (CTCL), belinostat 22 for relapsed or refractory
peripheral T-cell lymphoma (PTCL), panobinostat 3 for
multiple myeloma,3 and FK228 44 (romidepsin) for CTCL.
Chidamide 5 (Tucidinostat) is approved only in China for
PTCL.5 Nevertheless, solid tumour treatments with epigenetic
compounds is still needed.6 HDACs participate in the regulation
of gene expression by epigenetic mechanisms affecting
chromatin structure and function.7 HDACs are a subgroup of
eleven zinc-dependent proteins that deacetylate lysine residues
of proteins including the core nucleosomal histones H3, H4,
H2A and H2B, leading in turn to the repression of gene
expression. Some HDAC deacetylate non-histone proteins, like
HDAC6 for tubulin. HDACs are grouped in three classes, class
I (HDAC1-3, 8), class II (IIa HDAC4, 5, 7, 9 and IIb
HDAC6,10) and class IV (HDAC11). The seven NAD-
dependent sirtuins (SIRT1-7) represent the class III
HDACi are composed of a zinc-binding group (ZBG) linked by
a carbon structure to a “cap” group, mostly aromatic,12 in
interaction with the HDACs external solvent accessible surface.
HDACi limitations’ are their pharmacokinetics, the side effects
at the effective dosing and resistance,13 possibly avoided by
systemic low dosing administration for a better renormalization
of cancer cells.6 Bulk substituents and the absence of amide
bonds may favour the plasma stability of hydroxamates14 in
various species. The lack of selectivity of clinically approved
HDACi limits their specific applications.15 The selectivity
against class I HDACs results from para-substituted benzamide
inhibitors,16 4-alkylaminomethylbenzhydroxamic acid scaffold,
as in tubastatin or nexturastat, gives HDAC6 selectivity,17
whereas the trifluoromethyloxadiazole TMP-195 has HDAC7
selectivity.
Chart 1. Some HDAC inhibitors illustrate cap/ZBGs selectivity profiles.
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O
N
O
O
O
O
H
H
O
nexturastat
O
N
OH
N
OH
O
NH NH2
N
OH
OH
N
N
H
N
NH
1
2
3
N
NH NH2
H
H
2
belinostat
S
H
O
HN
O
HN
tubstatin A
HDAC6
1
vorinostat (SAHA)
S
O
O
O
N
S
N
O
O
HN
NH
nBu
O
OH
N
O
O
N
H
N
O
F
5
HN
Ph
F3C
O
H
N
HN
4
chidamide
class I
CI-994
class I
O
N
N
N
H
O
TMP-195
HDAC7
H
4
romidepsin
3
panobinostat
5
6
7
8
9
Scheme 1. Preparation of cap- and ZBG-bearing alkenes, validation and use in cross metathesis reaction.a.
O
17
18
, R3 = BOC
, R3 = H
O
vi, 90%
vii, 36%
O
O
OBOC
O
OR3
O
N
8
ii, , 50%
BOC
COOR2
iv, 91%
BOCN
R3N
COOMe
14
5
6
BOC
OH
10, R2 = H
11
MeO
O
MeO
O
12
O
O
10
11
12
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iii,
90%
19
20
, R3 = BOC
, R3 = H
HN
, R2 = Me
ii, 39%
N
H
vi, 93%
vii, 83%
O
O
6
v, , 36%
HN
15
HN
BOC = COOtBu
Tr = C(Ph)3
BOC
Tr
MeO
O
MeO
O
NH
BOC
NHR3
O
O
ii, 86%
R1S
i,
Tr
S
5
ii, , 48%
COOMe
O
21
, R4 = Tr
22, R4 = H
vi, 84%
viii, 83%
O
2
O
9
7, R1 = H
8
, R1 = (CH2)3-CH=CH2
13
STr
16
92%
2
MeO
O
MeO
O
SR4
a: i) K2CO3, ACN. Br-(CH2)3-CH=CH2. ii) Grubbs 1st generation catalyst, DCM, reflux, 6+1h. iii) CH3OH, H2SO4. iv) K2CO3, DMF, Br-
(CH2)3-CH=CH2. v) 2nd generation catalyst, DCM, reflux. vi) H2, Pd/C, AcOEt. vii) TFA, DCM. viii) TFA:TES:DCM 1:0.1:1
Current compound design is focused on HDAC1-3, 4, 6 and 8
selective inhibitors due to a better biological knowledge. We
previously validated cross metathesis (CM) to prepare alkyl-
based hydroxamate and benzamide as HDACi.18 We present an
extension with various ZBG: hydroxamic acids, thiols and
benzamide as in SAHA, romidepsin and chidamide. Other ZBG
were not explored.19 We selected indole and naphthyl20 groups
found as caps in HDACi. Indoles are known to be reluctant in
CM reaction but their presence reduce HDACi cardiac
toxicity.21 A naphtoxy group instead of a naphthylamide may
comply with better plasma stability. Despite its simplicity our
naphthyl series was unknown but similar to a “para” compound
used to develop HDAC8 inhibitors with large cap groups.22
Compounds 18, 20 and 22 were tested for global HDAC
inhibition using our BRET assays in living cells (Figure S1A-
C, BRET principle, supplementary material).23 SAHA (EC50
=
1.68µM) and CI-994 (EC50 = 3.81µM) were used as controls
(Table 1, Figure S2A supplementary material) and gave results
similar to previous studies. 23,24 Compounds 18 and 20 were able
to enter cells and to induce an increase of histone H3
acetylation, illustrated by an increase of the BRET signal. The
absence of activity for thiol 22 may be due to the formation of
a disulphide bridge as in psammaplins in the cellular
environment. These experiments gave for the hydroxamate 18
an EC50 of 7.84µM and for the benzamides 20 an EC50 of 8.14
µM. Comparison of HDACi-induced BRET max values,
obtained from dose-response experiments (Figure S2B,
supplementary material) showed that compound 18, SAHA and
CI-994 lead to similar maximal level of histone H3 acetylation
whereas compound 20 appeared significantly less active. The
best HDACi 18 was further studied with SAHA and CI-994 as
controls in a dose escalation experiments (Figure S3
supplementary material) for the simultaneous determination of
viability (Table 2) and toxicity towards the selected cancer
cells. These experiments demonstrated that all tested
compounds decreased cancer cell viability through induction of
toxicity (Figure S3 supplementary material). The IC50 obtained
for the various cancer cell lines used (Table 2) is coherent with
the EC50 obtained using BRET assay (Table 1). Compound 18
is less toxic than SAHA (about 4 fold) and A549 cells are the
less sensitive to this compound. We noticed a correlation
between induction of histone H3 acetylation and toxicity. For
compound 18, we determined HDAC and sirtuin selectively,
using a standardized in vitro assay (Table 3, Figure S4
supplementary material). At 10 M concentration compound 18
was able to partially inhibit HDAC classes I (HDAC1,2,3,8),
IIb (HDAC6,10) and IV (HDAC11), and no inhibition was
noticed for class IIa and class III. 100% inhibition was obtained
only for HDAC6 (class IIb). The dose-responses in vitro (Figure
S4, supplementary material) showed that compound 18 is
selective for HDAC6 (IC50 = 95 nM, Table 3), about tenfold less
active for HDAC3, and 17 to 37-fold less for the other isoforms.
The reference compound TSA was not selective, with better
activity against HDAC HDAC1-3,6 and 10 than for other
isoforms. The selective inhibition of HDAC6 prompted us to
The alkene 8 was prepared from thiol 7 (Scheme 1) to
complement our library ZBG-protected alkenes 5 and 6. A
general TFA deprotection of the BOC and trityl groups was
expected, with TES for the trityl one. The cap-bearing alkene
12 was prepared from naphthol 10. The CM reactivity of
alkenes 8 and 12 was verified and gave compounds 9 and 13
respectively in moderate to good yields. The CM between the
ester 12 and the alkenes 5, 6 and 8 gave access respectively to
three alkenes 14-16 in good isolated yields with our continuous
injection protocol of Grubbs 1st generation catalyst. The Grubbs
2nd generation catalyst was used for the benzamide 15. The
possible dimers formed in each case were separated.
Compounds 14-16 were reduced to compounds 17, 19 and 21
respectively, and deprotection gave the hydroxamate 18,
benzamide 20 and the thiol 22. The direct CM with free NH
indole remains difficult (Scheme S1, supporting information)
and was partly solved by the methylation of the amide 23 to
give 24, still poor substrate for CM, even with the Grubbs 2nd
generation catalyst, whatever the alkene used. In this series only
the reduction of compound 27 to 29 worked and the
deprotection of 29 did not allow recovery of the expected
benzamide. The conversion of compound 24 to
a
butenylcarboline may be evaluated in the future in CM. These
difficulties with the indole series prompted us to focus on the
naphthyl series for biological testing. As a summary, Grubbs I
catalyst is well suited for thioalkenes and N,O diBOC
hydroxamates. The Grubbs II catalyst must be preferred for the
benzamide derivatives, or other more reactive catalysts. The cap
group should be apolar (supplementary information, table S1).
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and sustained histone H3 acetylation. The changes in histone
examine histone H3 and -tubulin acetylation in malignant
pleural mesothelioma (MPM, meso 163) and lung
adenocarcinoma (ADCA, A549) cells by western-blot. SAHA
was used as a control for the induction of histone H3 and -
tubulin acetylation and CI-994 for the only induction of histone
H3 acetylation. In meso 163 cells (Figure 2A upper panels),
SAHA and compound 18 induced a rapid and transitory histone
H3 acetylation whereas the benzamide CI-994 induced rapid
Table 1. EC50 for the induction of histone acetylation measured
by BRET assay in Met-5A pleural mesothelial cells.
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H3 acetylation modulate the expression of a wide range of
genes. In this study, we measured the mRNA level of E-
cadherin, an ‘epitheloid status’ marker of epithelial to
mesenchymal transition (EMT)25 and the expression of two
TSG was evaluated: Semaphorin-3F (Sema-3F) which reduces
tumor angiogenesis and progression and which is lost or
reduced in lung cancers,26 and p21 involved in cell cycle.27
Table 3. Inhibition profile and isoform selectivity of compound
18 compared to reference compounds.
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10
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IC50 (M)
Cpd.
18
20
SAHA
CI-994
% inhibition
18, 10 µM
Target
Ref.
18
3.5
3.4
1.0
na
Ref.
0.011
0.016
0.010
2.5
7.84 ± 0.18 8.14 ± 0.32 1.68 ± 0.19 3.81 ± 0.17
EC50 (M)
HDAC1
HDAC2
HDAC3
HDAC4
HDAC5
HDAC6
HDAC7
HDAC8
HDAC9
HDAC10
HDAC11
sirtuin1
sirtuin2
sirtuin3
sirtuin6
84,7
67,1
87,9
-4,8
TSA
TSA
TSA
TSA
TSA
TSA
TSA
TSA
TSA
TSA
B
EC50 values were determined using GraphPad Prism, Prism 6 for
Windows, by curve fitting using a sigmoidal dose-response model.
Values represent means ± standard error of at least three
independent experiments.
Table 2. IC50 (µM) values for viability of Meso 163 and 13,
A549 and ADCA72 cell lines treated with 18, SAHA and CI-
994 (72h).
2,8
na
1.6
104,1
-16,3
93,1
-14,3
82,3
57,2
-2,6
0.095
na
0.022
0.98
0.79
5.1
Cpd.
Meso 13
Meso 163
A549
ADCA 72
1.6
na
SAHA 3.79 ± 0.18 3.67 ± 0.17 4.12 ± 0.18 3.95 ± 0.23
CI-994 7.83 ± 0.19 15.77 ± 0.19 15.96 ± 0.19 3.90 ± 0.18
1.6
6.6
Nd
Nd
Nd
0.040
5.2
18
15.62 ± 0.12 15.86 ± 0.14 62.36 ± 0.18 15.72 ± 0.16
IC50 values were determined using GraphPad Prism, Prism 6 for
Windows, by curve fitting using a sigmoidal dose-response model.
Values represent means ± standard error of at least three
independent experiments.
c
6.7
-11,8
-8,2
c
17
d
36
-13,4
EX527
Figure 2. Effect of compound 18 (20 µM), SAHA (2.5 µM) and
CI-994 (10 µM) on A) histone H3 and -tubulin acetylation in
MPM and lung ADCA cells. Meso 163 and A549 cells were treated
with the compounds for 6 or 20h. Histone H3 and -tubulin
acetylation were analysed using western-blot. Left column
indicates the molecular weight; and on B) E-cadherin, Sema-3F and
P21 expression in MPM and lung ADCA cells. Meso 163 and A549
cells were treated with the compounds for 24h. mRNA expression
of E-cadherin, Sema-3F and p21 was measured using real-time
PCR. Results are means ± S.E.M. of four independent experiments.
* p < 0.05; ** p < 0.01; **p < 0.001.
TSA: (S)-trichostatin A. b: scriptaid. c: suramin. d: niacinamide.
na: not active. Nd: not determined. Ref = reference compound.
Figure 2B shows that compound 18, SAHA and CI-994 induced
the expression of E-cadherin and of both TSGs suggesting a
beneficial effect on MPM and lung cancer cells. Like SAHA,
compound 18 induced a sustained -tubulin acetylation
demonstrating its inhibitory effect on cytoplasmic HDAC6,
coherent with its high HDAC6 inhibition activity.28 As
expected, CI-994 did not increase -tubulin acetylation
according to the specific activity of benzamide on nuclear
HDAC.29 In A549 cells (Figure 2A lower panels), similar
results were obtained. The only difference with meso 163 cells
was the sustained activity of SAHA and compound 18 on
histone H3 acetylation over time.
Insight into the ligand positioning and binding modes of
compound 18 into eleven metal-dependant HDAC isoforms
was performed by molecular docking study. Docking
simulations were able to reproduce the co-crystal inhibitor
binding modes with RMSD values below 1.5 Å for each isoform
and took into account the important interactions between
hydroxamic acid derivatives in the active center of HDAC
isoforms.30,31 The method was additionally validated by
comparing the ChemScore Fitness Function (CSFF) calculated
for (S)-TSA and compound 18 with their experimentally
obtained IC50 values within the each isoform.32
catalytic sites in HDAC1 homology model (A), crystal structure of human HDAC6 second catalytic domain
Figure 3. Comparative
presentation of
hydrophobic rim of the
(B), and first catalytic domain (C) with compound 18.
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methodology should be applicable in combinatorial strategies.
GOLD CSFF values calculated for ligand-specific HDAC were
in good agreement with the experimental inhibitory profile of
(S)-TSA and compound 18 compared within the same isoform
(Figures s5-s8 and Table s2, supplementary material). The
compound 18 chelates with the Zn2+ ion inside the HDAC
binding pockets, except for the isoforms which belong to the
HDAC class IIa (HDAC5/HDAC7 and HDAC9). The binding
modes of compound 18 into active pockets of HDAC1 and both
catalytic domains of HDA6 are presented in Figure 3 (other
HDACs in Figures s9-s20 and Table s2, supplementary
material). HDAC6 CDII has a wider hydrophobic rim of the
catalytic site (14.015 Ǻ) comparing to the hydrophobic rim of
HDAC1 (9.765 Ǻ). Furthermore, the second argument for more
favourable interaction of compound 18 with HDAC6 is a deeper
active channel, which is less restricted for inhibitor access.32
The naphthalene moiety of compound 18 forms favourable π-π
interaction with aromatic residue of Phe680 in HDAC6 CDII.
In addition, π-Sulphur interactions are formed between Met682
and naphthalene ring (Figure S14, supplementary material). A
bidentate binding mode was inspected for compound 18 inside
the binding pocket of HDAC6, whereas the monodentate
coordination was observed for the same compound in the active
site of HDAC1. The high HDAC6 inhibitory potency of this
compound could be explained by favourable interactions of the
naphthalene CAP group with the side chains located in the outer
rim of HDAC6 enzyme, as well as bidentate coordination with
Zn2+ ion. Additionally, the higher HDAC6 potency of
compound 18 may be also explained by the differences in the
length of the active pockets. It is previously shown that the
compounds with six carbon-spacer possess optimal distance
between hydroxamic acid and CAP group for HDAC1
inhibitory activity.33 When the spacer of the HDAC1 inhibitor
is longer than six carbons, it is less favourable to make the
hydrophobic interactions to the solvent exposed entrance of the
catalytic site. Compound 18 has aliphatic linker constructed of
eight carbon atoms, which may explain its selective HDAC6
inhibitory profile and less pronounced interactions with the side
chains in the outer rim of class I HDACs. Domain-selective
HDAC6 inhibitors studies30 prompted us to examine possible
domain selective affinity for compound 18. We observed
slightly different CSFF values calculated for (S)-TSA and
compound 18 between HDAC6 catalytic domains (higher CSFF
for CDI). To define whether the compound 18 possesses higher
affinity for CDI of HDAC6 isoform, advanced structure based
in silico and crystallographic studies should be performed, for
the more precise determination of the ligand’s domain
selectivity.
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Molecular docking rationalized the inhibition profile of
compound 18, introducing for the first time analysis of both
CD1 and CD2 domains of HDAC6. The biological interest of
compound 18 was demonstrated, with an increased acetylation
of histones and tubulin, associated with the stimulation of the
expression of E-cadherin, and TSGs such as SEMA3F and p21.
Experimental section
All biologically tested compounds were 95%+ pure as
determined by HPLC. Typical synthetic sequence illustrated for
compound 18. DCM, dichloromethane; TFA, trifluoroacetic
acid; TES: triethylsilane; EA, ethyl acetate; PE, petroleum
ether; TEA, trimethylamine; ACN: acetonitrile.
Methyl
(Z/E)-1-((8-((tert-butoxycarbonyl)((tert-
butoxycarbonyl)oxy)amino)-8-oxooct-4-en-1-yl)oxy)-2-
naphthoate 14. Grubbs catalyst (50 mg) in DCM (3mL) was
added over 6h (0,5mL/h rate) to a boiling solution of 5 (89mg,
0,33mmol) and 12 (208mg, 0,66mmol) in DCM (3mL) and
refluxed 1h more. After cooling the solvent was removed
(vacuum) and purification (flash chromatography silica,
PE/EA/TEA 99.5/0/0.5, 250mL, 97/2.5/0.5, 1L, 94.5/5/0.5, 1L
followed by preparative thin layer chromatography PE/EA:
1
97.5/2.5 and 95/5) gave 14 (88mg, 48%) as an orange oil. H
NMR (CDCl3) δ ppm: 1.53 (4s, 18H), 2.02 (m, 2H), 2.34 (m,
4H), 2.92 (m, 2H), 3.95 (3s, 3H), 4.12 (dt, 2H, J=1.0, 6.6 Hz),
5.55 (m, 2H), 7.58 (m, 3H), 7.84 (m, 2H), 8.27 (dd, 1H, J=6.49,
7.33Hz). 13C NMR (CDCl3) δ ppm: 23.9, 27.4, 27.5, 27.9, 28.0,
29.05, 29.1, 30.1, 30.3, 30.4, 36.8, 52.2, 85.2, 86.0, 119.2,
123.4, 123.7, 126.4, 126.7, 127.8, 128.3, 128.8, 129.7, 130.2,
130.8, 136.7, 157.4, 166.9, 170.2. HRMS Cald. for
C30H39NNaO9 [M+Na]+: 580,2517, Found: 580.2524.
Methyl 1-((8-(hydroxyamino)-8-oxooctyl)oxy)-2-naphthoate
18. TFA (0.33mL, 4mmol) was added to a solution of 17 (84mg,
0.15mmol) in DCM and the solution stirred for 3h. The crude
mixture was diluted with EA and washed (saturated aqueous
NaCl 3x5mL). The combined aqueous extracts were neutralized
(saturated aqueous NaHCO3, pH7) and extracted (EA,
3x20mL). The combined organic layers were dried (MgSO4)
and concentrated under vacuum to yield 18 (20mg, 36%) as an
orange oil.1H NMR (CDCl3) δ ppm: 1.33 (m, 4H), 1.52 (m, 4H),
1.85 (t, 2H, J=7.4Hz), 1.96 (t, 2H, J=7.3Hz), 3.89 (s, 3H), 4.05
(t, 2H, J=6.5Hz), 7.66 (m, 2H), 7.75 (s, 2H), 7.99 (dd, 1H, J=6.1,
7.1Hz), 8.19 (dd, 1H, J=6.3, 7,2Hz), 8.69 (s, 1H), 10.37(s, 1H).
13C NMR (CDCl3) δ ppm: 25.6, 25.9, 29.0, 29.1, 30.2, 32.7,
52.7, 76.4, 119.8, 123.5, 123.9, 126.7, 127.4, 128.5, 128.5,
129.0, 136.5, 156.6, 166.8, 169.6. HRMS Cald. for
C20H25NNaO5 [M+Na]+: 382.1625, Found: 382.1626.
In conclusion CM was successfully used to prepare rapidly with
a generic method a series of alkyl-based HDAC inhibitors
bearing the most common ZBGs and one of them is in vitro a
nanomolar selective HDAC6 inhibitor. The method can be
adapted to inhibitors of other relevant biological targets. The
ASSOCIATED CONTENT
Supporting Information. Synthesis, characterizations for all
1
compounds, H/13C NMR spectra and HPLC data for compounds
18, 20 and 22, biological experiments, docking methods, Figures
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ACS Medicinal Chemistry Letters
13. Robey, R. W.; Chakraborty, A. R.; Basseville, A.; Luchenko, V.;
S1-S20. Authors will release the PDB files upon article publication.
The Supporting Information is available free of charge on the ACS
Publications website.
Bahr, J.; Zhan, Z.; Bates, S. E. Histone Deacetylase Inhibitors:
Emerging Mechanisms of Resistance. Mol. Pharm. 2011, 8, 2021–
2031.
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AUTHOR INFORMATION
14. Hermant, P.; Bosc, D.; Piveteau, C.; Gealageas, R.; Lam, B.; Ronco,
C.; Roignant, M.; Tolojanahary, H.; Jean, L.; Renard, P.-Y.; Lemdani,
M.; Bourotte, M.; Herledan, A.; Bedart, C.; Biela, A.; Leroux, F.;
Deprez, B.; Deprez-Poulain, R. Controlling Plasma Stability of
Hydroxamic Acids: A MedChem Toolbox. J. Med. Chem. 2017, 60,
9067–9089.
15. Witt, O.; Deubzer, H. E.; Milde, T.; Oehme, I. HDAC Family: What
Are the Cancer Relevant Targets? Cancer Lett. 2009, 277, 8–21.
16. Bressi, J. C.; Jennings, A. J.; Skene, R.; Wu, Y.; Melkus, R.; Jong,
R. D.; O’Connell, S.; Grimshaw, C. E.; Navre, M.; Gangloff, A. R.
Exploration of the HDAC2 Foot Pocket: Synthesis and {SAR} of
Substituted N-(2-Aminophenyl)Benzamides. Bioorg. Med. Chem. Lett.
2010, 20, 3142 – 3145.
17. Estiu, G.; Greenberg, E.; Harrison, C. B.; Kwiatkowski, N. P.;
Mazitschek, R.; Bradner, J. E.; Wiest, O. Structural Origin of
Selectivity in Class II-Selective Histone Deacetylase Inhibitors. J. Med.
Chem. 2008, 51, 2898–2906.
18. Zwick, V.; Nurisso, A.; Simões-Pires, C.; Bouchet, S.; Martinet, N.;
Lehotzky, A.; Ovadi, J.; Cuendet, M.; Blanquart, C.; Bertrand, P. Cross
Metathesis with Hydroxamate and Benzamide BOC-Protected Alkenes
to Access {HDAC} Inhibitors and Their Biological Evaluation
Highlighted Intrinsic Activity of BOC-Protected Dihydroxamates.
Bioorg. Med. Chem. Lett. 2016, 26, 154–159.
Corresponding Author. *Dr. Philippe BERTRAND,
Philippe.bertrand@univ-poitiers.fr.
Author Contributions. The manuscript was written through
contributions of all authors.
Funding Sources. Regions Nouvelle Aquitaine and Pays de la
Loire, Ligue Contre le Cancer: committees of Vendée and
Charente-Maritime, D.A., K.N., and D.R. acknowledge the
project (contract no. 172033) supported by the Ministry of
Education, Science, and Technological Development of the
Republic of Serbia.
ACKNOWLEDGMENT
Authors thank the Centre National de la Recherche Scientifique,
University of Poitiers, COST Action CM1406, Professor Olaf
Wiest group for providing us homology models of eleven HDAC
isoforms (HDAC1-HDAC11) used for molecular docking study.
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in vitro
HDAC6: 95 nM
HDAC1-3,8: 1-3.5 M
HDAC10: 1.6 M
HDAC11: 6.6 M
HDAC4-7,9: not active
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