Synthesis and biological evaluation of solubilized sulfonamide analogues of the phosphatidylinositol 3-kinase inhibitor ZSTK474

Article abstract of DOI:10.1016/j.bmc.2019.02.050

Replacing one of the morpholine groups of the phosphatidylinositol 3-kinase (PI3K) inhibitor ZSTK474 with a variety of sulfonamide-linked solubilizing substituents produced a new class of active and potent PI3Kα inhibitors, with several derivatives demonstrating high PI3Kα enzyme potency and good cellular potency in two human derived cell lines. The overall results suggest a preference for linear and somewhat flexible solubilizing functions. From this series, compound 16, also known as SN32976, was selected for advanced preclinical evaluation.

Full text of DOI:10.1016/j.bmc.2019.02.050

Accepted Manuscript
Synthesis and biological evaluation of solubilized sulfonamide analogues of the
phosphatidylinositol 3-kinase inhibitor ZSTK474
Anna C. Giddens, Swarna A. Gamage, Jackie D. Kendall, Woo-Jeong Lee,
Bruce C. Baguley, Christina M. Buchanan, Stephen M.F. Jamieson, James M.J.
Dickson, Peter R. Shepherd, William A. Denny, Gordon W. Rewcastle
PII:
S0968-0896(18)32045-5
https://doi.org/10.1016/j.bmc.2019.02.050
BMC 14786
DOI:
Reference:
Bioorganic & Medicinal Chemistry
To appear in:
Received Date:
Revised Date:
Accepted Date:
5 December 2018
17 February 2019
24 February 2019
Please cite this article as: Giddens, A.C., Gamage, S.A., Kendall, J.D., Lee, W-J., Baguley, B.C., Buchanan, C.M.,
Jamieson, S.M.F., Dickson, J.M.J., Shepherd, P.R., Denny, W.A., Rewcastle, G.W., Synthesis and biological
evaluation of solubilized sulfonamide analogues of the phosphatidylinositol 3-kinase inhibitor ZSTK474,
Bioorganic & Medicinal Chemistry (2019), doi: https://doi.org/10.1016/j.bmc.2019.02.050
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Synthesis and biological evaluation of solubilized sulfonamide analogues of
the phosphatidylinositol 3-kinase inhibitor ZSTK474
Anna C. Giddensa, Swarna A. Gamagea Jackie D. Kendalla,b, Woo-Jeong Leec, Bruce C.
,
Baguleya,b, Christina M. Buchananb,c, Stephen M. F. Jamiesona,b, James M.J. Dicksonb,d Peter
R. Shepherda,b,c, William A. Dennya,b, Gordon W. Rewcastlea,b,*
aAuckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The
University of Auckland, Private Bag 92019, Auckland 1142, New Zealand, bMaurice Wilkins
Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019,
Auckland 1142, New Zealand, cDepartment of Molecular Medicine and Pathology, Faculty of
Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland
1142, New Zealand, and School of Biological Sciences, Faculty of Science, The University of
Auckland, Private Bag 92019, Auckland 1142, New Zealand.
*Corresponding author.
E-mail address: g.rewcastle@auckland.ac.nz
Phone: +64-9-9236147
Fax: +64-9-3737502
Keywords: Phosphatidylinositol 3-kinase, PI3K, p110α, ZSTK474, SN32976
Abstract
Replacing one of the morpholine groups of the phosphatidylinositol 3-kinase (PI3K) inhibitor
ZSTK474 with a variety of sulfonamide-linked solubilizing substituents produced a new class
of active and potent PI3Kα inhibitors, with several derivatives demonstrating high PI3Kα
enzyme potency and good cellular potency in two human derived cell lines. The overall results
suggest a preference for linear and somewhat flexible solubilizing functions. From this series,
compound 16, also known as SN32976, was selected for advanced preclinical evaluation.
1. Introduction
Phosphatidylinositol 3-kinases (PI3Ks) are a family of three distinct classes (I, II and

III) of lipid kinases that play key roles in cell and tissue physiology.1-4 The three class-Ia PI3Ks
(PI3Kα/β/δ) and the sole class-Ib PI3K (PI3Kγ) couple growth factor receptors and G-protein
coupled receptors respectively to a wide range of downstream pathways.5-6 These enzymes
have different mechanisms of activation and different kinetic properties,7 but all use
phosphatidylinositol-4,5-bisphosphate (PIP2) to produce phosphatidylinositol-3,4,5-trisphos-
phate (PIP3). The cellular levels of PIP3 are tightly controlled by phosphatases including PTEN
which dephosphorylates PIP3 back to PIP2.8,9 The importance of this pathway in cancer is
highlighted by the fact that defects in both the kinase and phosphatase activities are commonly
observed in tumours, and there is now increasing evidence that a high proportion of human
cancers depend strongly on PI3Kα for their survival and resistance to therapy.8-15 Selective
PI3Kα inhibition also appears to be less immunosuppressive in vivo compared with PI3Kδ or
pan-class I inhibition.16 Therefore the targeting of PI3K, and more specifically the p110α
isoform, with small molecule inhibitors has been widely explored and a number of programs
to develop PI3K inhibitors are currently in progress,5, 17- 25 with two p110α-specific inhibitors
in clinical trial.26-28
2-(Difluoromethyl)-1-[4,6-di(4-morpholinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole
(ZSTK474) (1) (Fig. 1) is a potent ATP-competitive pan-class I PI3K inhibitor, with high
selectivity over other classes of PI3K and protein kinases,29-31 that demonstrated antitumour
activity in vivo against human tumour xenografts.29, 31 A crystal structure of ZSTK474 bound
in the p110δ active site has shown that it binds in the same way as other morpholine-containing
inhibitors,32 with one of the morpholine oxygen atoms making a critical H-bond to the hinge
region Val828 residue, and the benzimidazole N-3 making another H-bond to Lys779. The
important CHF2 group forms a hydrogen bond contact to Pro758 in the hydrophobic affinity
pocket, while the second morpholino group adopts a somewhat twisted chair conformation and
projects out of the ATP-binding pocket towards solvent. 32

Fig. 1. Structures of compounds 1-3.
We performed a structure activity relationship (SAR) study of this compound, and showed
that the addition of a methoxy group at the 4-position of the benzimidazole resulted in
improved selectivity for the p110α isoform of PI3K over the other isoforms, relative to 1.33
Also, since only one of the morpholine substituents of 1 is involved in binding to the various
p110 isoforms (Val828 in p110δ is equivalent to Val851 in p110α and Val854 in p110β), we
found that the second (solvent-oriented) morpholine could be replaced by sulfonamide
derivatives, such as the piperazine 2.34 This compound, and a number of related analogues,
showed good potency against the p110α isoform of PI3K, and good selectivity over the
p110β and p110δ isoforms, confirming piperazine-sulfonamide groups as good alternatives
for the second morpholine of 1.34 It is noted that a piperazine-sulfonamide unit has also
recently been incorporated in an example of a bifunctional MEK1/PI3K inhibitor that was
derived from 1.35 Unfortunately, compounds like 2 did not possess good bioavailability, due
to limited aqueous solubility (similar to 1 itself), leading us to investigate more soluble
derivatives.
Previously we had shown that derivatives of 1, substituted by solubilizing groups at the
4-position of the benzimidazole, such as 3, had good aqueous solubility, and displayed
moderate in vivo activity in a U87MG xenograft model,36 so we began by targeting compound
11 (Scheme 1), which represents a combination of 2 and 3.
2.
2.1. Chemistry
For the synthesis of 11 (Scheme 1), the use of a benzyl protecting group for the 4-
Results and discussion
oxygen atom of the benzimidazole was found to give superior results to the TBDMS or TIPS
protecting groups that had been employed earlier.33 Thus, reaction of 4, readily prepared from
known precursors,37 with 2,4-dichloro-6-(4-morpholinyl)-1,3,5-triazine gave 5, which was
combined with Boc-piperazine to give 6, which was then converted to phenol 7 by
hydrogenation over palladium on carbon. Successive reaction of 7 with 3-bromo-1-propanol,
methanesulfonyl chloride, and aqueous dimethylamine then gave amine 9, which was readily
converted to sulfonamide 11, by standard procedures.34

Scheme 1. Reagents and conditions: (i) 2,4-dichloro-6-(4-morpholinyl)-1,3,5-triazine, K2CO3,
acetone, rt; (ii) 4-Boc-piperazine, DIPEA, THF, rt; (iii) H2, Pd/C, THF-MeOH; (iv) 3-bromo-
1-propanol, K2CO3, DMF, rt; (v) MsCl, Et3N, THF, 0 °C, then aq. Me2NH, rt; (vi) TFA, CH2Cl2
rt, then aq. NH3; (vii) MsCl, K2CO3, CH2Cl2, 0 °C then rt.
Compounds 14-28 (Scheme 2) and 32 and 33 (Scheme 3) represent derivatives of 2,
with the methyl group replaced by aminoalkyl substituents. Aminoethyl derivatives 14-28 were
prepared via the vinyl sulfone 13, prepared by reaction of piperazine 1234 with 2-
chloroethanesulfonyl chloride. Michael addition of the appropriate amines to 13 then gave the
compounds of Scheme 2, with the exception of sulfone 24, which was prepared by KMnO4
oxidation of sulfide 22. Aminopropyl derivatives 32 and 33 were readily prepared by direct
reaction of the preformed sulfonylpiperazines 30 and 3138 with chloride 2933 (Scheme 3).

Scheme 2. Reagents and conditions: (i) Cl(CH2)2SO2Cl, DIPEA, CH2Cl2, -15 °C, then 0 °C;
(ii) (for 14-23 and 25-28) RH, THF or dioxane, rt, or 80 °C, or 100 °C; (iii) (for 24) aq. KMnO4,
acetone, AcOH, rt.
Scheme 3. Reagents and conditions: (i) DIPEA, THF or DMSO, rt.
Pyridyl-sulfonyl piperazine derivatives 34-36 (Scheme 4) were prepared by reaction of
the appropriate sulfonyl chlorides with 12, while heterocyclic ring variants 49-54 (Scheme 5)
were prepared by reaction of the respective vinylsulfones with aqueous dimethylamine, using
procedures similar to those of Scheme 2.

Scheme 4. Reagents and conditions: (i) (for 34) 3-pyridinesufonyl chloride, DIPEA, CH2Cl2,
rt; (ii) (for 35) 2-[2-(chlorosulfonyl)ethyl]pyridine hydrochloride, DIPEA, CH2Cl2, rt; (iii) (for
36) 4-[2-(chlorosulfonyl)ethyl]pyridine hydrochloride, DIPEA, CH2Cl2, rt.
Scheme 5. Reagents and conditions: (i) Cl(CH2)2SO2Cl, DIPEA, CH2Cl2, 0 °C; (ii) aq.
Me2NH, THF, rt.
The compounds of Schemes 6, 7, and 8 represent examples where a solubilizing
aminopropyl substituent is attached to either the sulfonamide nitrogen (compounds 57 and 58),
or another nitrogen atom in the molecule (compounds 64-66, 71 and 72). Thus, alkylation of
sulfonamide 5534 with 3-bromo-1-propanol gave alcohol 56, which was then converted to
products 57 and 58 via in situ reaction of a mesylate intermediate with the appropriate amines
(Scheme 6). In the case of intermediates 60 and 68 (Schemes 7 and 8 respectively), the N-
propanol substituents were introduced via preformed intermediates 5939 and 67, by reaction
with compound 29. As with alcohol 56, in situ reaction of mesylate intermediates gave amines
61-63, 69 and 70, which were then converted to the product sulfonamides 64-66, 71 and 72 by

standard procedures.34
Scheme 6. Reagents and conditions: (i) 3-bromo-1-propanol, K2CO3, DMF, rt; (ii) MsCl, Et3N,
THF, 0 °C, then aq. Me2NH, rt; (iii) MsCl, Et3N, THF, 0 °C, then morpholine, rt.
Scheme 7. Reagents and conditions: (i) 29, DIPEA, DMF, rt; (ii) MsCl, Et3N, THF, 0 °C, then
aq. Me2NH, rt; (iii) MsCl, Et3N, THF, 0 °C, then morpholine, rt; (iv) MsCl, Et3N, THF, 0 °C,
then Boc-piperazine, rt. (v) TFA, CH2Cl2, rt, then aq NH3; (vi) MsCl, DIPEA, CH2Cl2, 0 °C,
then rt.

Scheme 8. Reagents and conditions: (i) 29, DIPEA, DMF, rt; (ii) MsCl, Et3N, THF, 0 °C, then
aq. Me2NH, rt; (iii) MsCl, Et3N, THF, 0 °C, then morpholine, rt; (iv) TFA, CH2Cl2, rt, then aq
NH3; (v) MsCl, K2CO3, CH2Cl2, 0 °C, then rt.
Finally, the reversed sulfonamide derivatives 77 and 78 were prepared by reaction of
preformed intermediates 75 and 76 with compound 29 (Scheme 9).
Scheme 9. Reagents and conditions: (i) Me2NCH2CH2NH2, CH2Cl2, 0 °C, then rt; (ii) H2, Pd/C,
MeOH; (iii) 29, DIPEA, THF, rt.
For biological evaluation, the prepared compounds (Table 1) were normally converted to their
hydrochloride or methanesulfonate salts, with the latter routinely displaying greater aqueous
solubility. Hydrochlorides were usually sufficiently soluble with aliphatic amines, but with
heterocyclic and heteroaromatic amines, methanesulfonates were preferred.
2.2
Enzyme Data
The compounds in Table 1 were tested for their inhibitory activity against the p110α,

p110β, and p110δ isoforms of PI3K using Homogeneous Time Resolved Fluorescence
(HTRF) assays. Compounds were generally more selective for the p110α isoform over p110β
and p110δ, and apart from compounds 11, 51, 53, 57, 71 and 72, did not show a significant
loss in p110α potency compared to the non-solubilized 2. Since compound 11, with the
solubilizing substituent on the benzimidazole 4-position, did not show the desired p110α
potency, we did not investigate this class of compound further, and all subsequent
compounds contain a 4-methoxy substituent, with the solubilizing substituent being
positioned elsewhere in the molecule.
Piperazine derivatives 14-28 and 32-33 showed that a variety of aliphatic amino
substituents and chain lengths were acceptable, while compounds 28 and 34-36 showed that
heteroaromatic amines were also acceptable. Compound 49 showed that removal of one of
the piperazine nitrogen atoms from 16 was acceptable in terms of p110α activity, although
selectivity over p110β and p110δ was significantly reduced. Compounds 50-54 showed that
good results were achievable with heterocyclic substituents other than piperazine, although
interestingly the N-methyl azetidine 51 and the N-methyl piperidine 53 were significantly less
potent than the analogous des-methyl compounds 50 and 52 respectively, indicating either a
favorable hydrogen bonding interaction of the sulfonamide NH for compounds 50 and 52, or else
an unfavorable conformational rigidity or steric interaction for compounds 51 and 53.
Compounds 57 and 58 investigated moving the aminoalkyl substituent from the
sulfonamide carbon to the sulfonamide nitrogen, while compounds 64-66, and 71 and 72
investigated moving the aminoalkyl substituent even further, to a nitrogen atom separate from
the sulfonamide group. All of these compounds were slightly less potent than the majority of
the earlier compounds, with the 3-N-alkylated piperidines 71 and 72, being even less potent
than the isomeric 4-N-alkylated piperidines 57 and 58. This is probably due to steric factors.
Finally, the pyrrolidine reversed sulfonamide 77 displayed good p110α potency while
the piperidine analogue 78 was slightly less potent against p110α, but more potent against
p110β and p110δ, especially when compared to the isomeric sulfonamide 52. This is possibly
due to a more favourable H-bonding arrangement for 78 in the p110β and p110δ binding
sites.
2.3. Cellular Data
The compounds were evaluated in cellular assays against two early passage human
cancer cell lines as described previously.34 These were NZB5, a brain (medulloblastoma) cell

line which contains the wild-type gene for p110α, and NZOV9, a poorly differentiated
ovarian (endometrioid) adenocarcinoma that is wild-type for expression of p53 protein but
contains a mutant p110α enzyme with a single amino acid substitution (Y1021C) in the
kinase domain leading to activation of the PI3K enzyme.
The compounds covered a broad range of IC50 values from 52 to 4,300 nM. The IC50 values
for the two cell lines were highly correlated with each other (p = 2 x 10-6, Spearman rank test,
SigmaPlot) but were nevertheless different; the IC50 ratios for the two cell lines covered a
range from 0.23 to 7.2. These ratios were weakly correlated with the IC50 values for the
NZB5 and NZOV9 lines (r < 0.01 in each case), suggesting that more potent compounds had
greater selectivity for the mutant enzyme. Weak correlations were found between the IC50
values for the NZB5 and NZOV9 cell lines and that for PI3K p110 (p = 0.002 and 0.005,
respectively). The corresponding correlations for the p110α and p110β isoforms were not
statistically significant. A striking result was the gain in potency, with both cell lines, in
going from an amino substituent in compound 14, to a methylamino substituent in compound
15, to a dimethylamino substituent in compound 16. This is probably related to lower
hydrogen bonding for 16 leading to greater permeability into cells. Pyridyl compounds 34–36
displayed even better cellular potency, presumably as a result of their pKa allowing for a
greater proportion of uncharged form at physiological pH, thus allowing for a faster diffusion
rate into cells (greater membrane permeability), compared to the more highly charged
aliphatic amines. Unfortunately this also comes at a cost of lower solubility at physiological
pH.
2.4. In vivo Data
Based on the enzyme and cellular potency data, 16 (hydrochloride) was evaluated in
vivo to investigate its anticancer efficacy in a U-87 xenograft model, alongside the equipotent
but insoluble 2, and the slightly less potent 20 (hydrochloride), all tested at their maximum
tolerated dose levels. Treatment with 16 resulted in a substantial reduction in tumor volume
that was significantly different from all other treatments at the completion of dosing (P<0.0001
vs control and 2, P<0.05 vs 20; one-way ANOVA) (Fig. 2). 20 also significantly reduced tumor
growth compared to control (P<0.05), while 2 had similar activity to control. All treatments
were well tolerated with no greater than 2% bodyweight loss on average during the treatment
period.

2 0 0 0
1 5 0 0
1 0 0 0
5 0 0
0
C o n t r o l
2
1 6
2 0
0
5
1 0
1 5
2 0
2 5
T i m e ( d a y s )
Fig. 2: In vivo antitumor efficacy of 2, 16 and 20 following daily treatment at 80 mg/kg, 60
mg/kg and 80 mg/kg, respectively in a U-87 MG human glioblastoma xenograft model.
3.
Conclusions
We have investigated a variety of different solubilizing positions for ZSTK474 (1)
based sulfonamide derivatives, and identified amino substitution on the sulfonamide carbon
portion of the molecule as being the most optimum. Dimethylamino substituents were superior
to methylamino, or primary amino, and as an example of this type, compound 16 (SN32976)
demonstrated potent biochemical, cellular and in vivo activity as the hydrochloride salt
(aqueous solubility 24 μg/mL). On the basis of this data, 16 was selected for advanced
evaluation as the more soluble methanesulfonate salt (aqueous solubility >59 μg/mL), the
results of which are published elsewhere.40 This work identified compound 15 as the major in
vivo metabolite of 16, while compounds 13 and 14 were also detected, although at much
lower concentrations.40
4.
4.1. Chemistry
Elemental analyses were performed by the Microchemical Laboratory, University of
Experimental
Otago, Dunedin, New Zealand. Melting points were determined on an Electrothermal IA9100
melting point apparatus and are as read. Proton NMR spectra were obtained on a Bruker
Avance-400 spectrometer at 400 MHz and are referenced to Me4Si. Low-resolution

atmospheric pressure chemical ionization (APCI) mass spectra were measured for organic
solutions on a ThermoFinnigan Surveyor MSQ mass spectrometer, connected to a Gilson
autosampler. High-resolution electron impact (HREIMS) and fast atom
bombardment (HRFABMS) mass spectra were determined on a Varian VG-70SE mass
spectrometer at nominal 5000 resolution. Thin-layer chromatography was carried out on
aluminium-backed silica gel plates (Merck 60 F254), with visualization of components by UV
light (254 nm). Column chromatography was carried out on silica gel, (Merck 230 - 400 mesh)
unless otherwise stated. Tested compounds were >95% purity, as determined by combustion
analysis, or by HPLC conducted on an Agilent 1100 system, using a reversed-phase C8 column
with diode array detection.
4.1.1. 3-[[2-(Difluoromethyl)-1-[4-[4-(methylsulfonyl)-1-piperazinyl]-6-(4-morpholinyl)-1,3,
5-triazin-2-yl]-1H-benzimidazol-4-yl]oxy]-N,N-dimethyl-1-propanamine (11)
A solution of 2-benzyloxy-6-nitroaniline37 (4.89 g, 20 mmol) in MeOH was
hydrogenated over Pt on carbon at 50 psi. After filtration through celite, the methanol was
removed under vacuum and the residue was dissolved in 2,2-difluoroacetic acid. The solution
was heated at 70 °C for 4 h, and the solvent was removed under vacuum. The residue was
treated with aq. K2CO3, extracted with EtOAc, and dried (Na2SO4). The solvent was
removed, and the residue was dissolved in hot i-Pr2O, decolourized with activated charcoal,
and filtered through celite. Removal of the solvent gave 4-(benzyloxy)-2-(difluoromethyl)-
1H-benzimidazole (4) (3.83 g, 70%): mp (i-Pr2O/hexanes) 152-154 °C; 1H NMR (DMSO-d6)
δ 13.42 (br s, 1H), 7.53 (br d, J = 7.3 Hz, 2H), 7.41 (br t, J = 7.3 Hz, 2H), 7.34 (br t, J = 7.3
Hz, 1H), 7.23 (t, JHF = 54.2 Hz, 2H), 6.90 (br s, 1H), 5.32 (s, 2H), MS (APCI) m/z: 275.2
(M+H+); Anal. Calcd. for C15H12F2N2O: C, 65.7; H, 4.4; N, 10.2; Found: C, 65.9; H, 4.4; N,
10.3%.
A mixture of 4 (1.05 g, 3.8 mmoL), 2,4-dichloro-6-(4-morpholinyl)-1,3,5-triazine (0.90
g, 3.8 mmol), and powdered K2CO3 (2.1 g, 15 mmol.) in acetone (30 mL) was stirred at room
temperature overnight. The mixture was diluted with water, and the solid was collected and
washed successively with water and MeOH, to give 4-(benzyloxy)-1-[4-chloro-6-(4-
morpholinyl)-1,3,5-triazin-2-yl]-2-(difluoromethyl)-1H-benzimidazole (5) (1.71 g, 95%): mp
(MeOH) 233-234 °C; 1H NMR (CDCl3) δ 7.99 (d, J = 8.4 Hz, 1H), 7.51 (t, JHF = 51.6 Hz,
1H), 7.50 (br d, J = 7.4 Hz, 2H), 7.37 (br t, J = 7.3 Hz, 2H), 7.33-7.28 (m, 2H), 6.86 (d, J =
8.0 Hz, 1H), 5.43 (s, 2H), 4.00-3.94 (m, 4H), 3.84-3.78 (m, 4H); MS (APCI) m/z: 473.2
(M+H+); Anal. Calcd. for C22H19ClF2N6O2: C, 55.9; H, 4.05; N, 17.8; Found: C, 55.9; H, 4.0;

N, 17.8%.
Reaction of 5 (0.166 g, 0.35 mmol) with tert-butyl 1-piperazinecarboxylate (78 mg,
0.43 mmol) and DIPEA (68 mg, 0.53 mmol) in THF at room temperature for 2 h, followed by
dilution with 1% aqueous acetic acid gave a quantitative yield of tert-butyl 4-[4-[4-
(benzyloxy)-2-(difluoromethyl)-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,5-triazin-2-
yl]piperazine-1-carboxylate (6), as a white solid: mp (MeOH) 215-217 °C; 1H NMR (CDCl3)
δ 7.87 (d, J = 8.4 Hz, 1H), 7.51 (br d, J = 7.0 Hz, 2H), 7.49 (t, JHF = 53.5 Hz, 1H), 7.39-
7.34(m, 5H), 6.80 (d, J = 8.0 Hz, 1H), 3.85 (m, 8H), 3.77 (m, 4H), 3.53 (m, 4H), 1.50 (s, 9H);
MS (APCI) m/z: 623.0 (M+H+); Anal. Calcd. for C31H36F2N8O4: C, 59.8; H, 5.8; N, 18.0;
Found: C, 59.7; H, 6.0; N, 18.0%.
Hydrogenation of 6 with 10% Pd on carbon in MeOH/THF gave a quantitative yield of
tert-butyl 4-[4-[2-(difluoromethyl)-4-hydroxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]piperazine-1-carboxylate (7): mp (MeOH) 228-230 °C; 1H NMR (CDCl3) δ
7.81 (d, J = 8.4 Hz, 1H), 7.55 (t, JHF = 53.6 Hz, 1H), 7.32 (t, J = 8.2 Hz, 1H), 6.90 (d, J = 8.0
Hz, 1H), 3.90 - 3.84 (m, 8H), 3.80 - 3.76 (m, 4H), 3.55 – 3.51 (m, 4H), 1.50 (s, 9H); MS
(APCI) m/z: 533.3 (M+H+); Anal. Calcd. for C24H30F2N8O4: C, 54.1; H, 5.7; N, 21.0; Found:
C, 54.15; H, 5.8; N, 21.3%.
A mixture of 7 (0.60 g, 1.1 mmol), 3-bromo-1-propanol (0.47 g, 3.3 mmol), and
powdered K2CO3 (0.80 g, 5.5 mmol) in dry DMF (20 mL) was stirred at room temperature
for 8 h. Dilution with water gave tert-butyl 4-[4-[2-(difluoromethyl)-4-(3-hydroxypropoxy)-
1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-1-piperazinecarboxylate (8)
(0.66 g, 99% yield): 1H NMR (CDCl3) δ 7.94 (dd, J = 8.4. 0.7 Hz, 1H), 7.49 (t, JHF = 53.4
Hz, 1H), 7.34 (t, J = 8.1 Hz, 1H), 6.92 (dd, J = 8.0, 0.6 Hz, 1H), 4.47 (t, J = 5.9 Hz, 2H),
3.98 (t, J = 5.4 Hz, 2H), 3.87 (m, 8H), 3.79 (m, 4H), 3.54 (m, 4H), 3.30 (m, exchangeable
with D2O, 1H), 2.14 (pentet, J = 5.8 Hz, 2H), 1.50 (s, 9H).
A mixture of 8 and Et3N (0.34 g, 3.3 mmol) in THF (20 mL) was cooled to 0 °C and
methanesulfonyl chloride (0.32 g, 2.8 mmol) was added dropwise. After 1 h, 40% aqueous
Me2NH (6 mL) was added, and the resulting mixture was stirred at room temperature for 36
h. The volatiles were removed under vacuum, and the residue was diluted with water, and
extracted into CH2Cl2. Drying and removal of the solvent gave tert-butyl 4-[4-[2-
(difluoromethyl)-4-[3-(dimethylamino)propoxy]-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-1-piperazinecarboxylate (9) as an oil: 1H NMR (CDCl3) δ 7.87 (dd, J =
8.4. 0.6 Hz, 1H), 7.48 (t, JHF = 53.5 Hz, 1H), 7.33 (t, J = 8.2 Hz, 1H), 6.85 (d, J = 7.8 Hz,
1H), 4.31 (t, J = 6.7 Hz, 2H), 3.87 (m, 8H), 3.79 (m, 4H), 3.53 (m, 4H), 2.51 (t, J = 7.2 Hz,

2H), 2.26 (s, 6H), 2.13 (pentet, J = 7.0 Hz, 2H), 1.50 (s, 9H).
A solution of 9 in CH2Cl2 (10 mL) was treated with with TFA (5 mL) and the mixture
was stirred at room temperature for 3 h. The solution was poured onto ice and the mixture
was made basic with aq. NH3. The organic layer was dried, and removed under vacuum to
give N-[3-[[2-(difluoromethyl)-1-[4-(4-morpholinyl)-6-(1-piperazinyl)-1,3,5-triazin-2-yl]-
1H-benzimidazol-4-yl]oxy)propyl]-N,N-dimethylamine (10) as a solid: 1H NMR (CDCl3) δ
7.89 (dd, J = 8.4. 0.7 Hz, 1H), 7.50 (t, JHF = 53.5 Hz, 1H), 7.31 (t, J = 8.2 Hz, 1H), 6.84 (d, J
= 8.0 Hz, 1H), 4.32 (t, J = 6.8 Hz, 2H), 3.86 (m, 8H), 3.78 (m, 4H), 2.95 (m, 4H), 2.53 (t, J =
7.2 Hz, 2H), 2.27 (s, 6H), 2.13 (pentet, J = 6.9 Hz, 2H).
A stirred mixture of 10 (297 mg, 0.57 mmol) and powdered K2CO3 (1 g) in CH2Cl2 was
cooled to 0 °C, and methanesulphonyl chloride (0.4 g) was added. The mixture was allowed
to warm to room temperature and, after 2 h, it was diluted with water, and the organic layer
was separated and dried. Chromatography on alumina, eluting first with CH2Cl2/EtOAc (1:1)
and then with EtOAc gave 11 (200 mg, 59% yield): 1H NMR (CDCl3) δ 7.84 (dd, J = 8.4. 0.6
Hz, 1H), 7.43 (t, JHF = 53.5 Hz, 1H), 7.33 (t, J = 8.2 Hz, 1H), 6.86 (d, J = 7.7 Hz, 1H), 4.32
(t, J = 6.8 Hz, 2H), 4.02 (m, 4H), 3.88 (m, 4H), 3.78 (m, 4H), 3.33 (m, 4H), 2.81 (s, 3H),
2.54 (t, J = 7.2 Hz, 2H), 2.28 (s, 6H), 2.14 (pentet, J = 7.0 Hz, 2H); MS (APCI) m/z: 596.0
(M+H+).
Hydrochloride: mp (EtOH) 243-247 °C; 1H NMR (DMSO-d6) δ 10.26 (br s, 1H,
exchangeable with D2O), 7.92 (d, J = 8.3 Hz, 1H), 7.70 (t, JHF = 52.8 Hz, 1H), 7.42 (t, J =
8.2 Hz, 1H), 6.99 (d, J = 7.9 Hz, 1H), 4.33 (t, J = 6.1 Hz, 2H), 3.97-3.92 (m, 4H), 3.84-3.79
(m, 4H), 3.72-3.67 (m, 4H), 3.30-3.22 (m, 6H), 2.91 (s, 3H), 2.81 (s, 6H), 2.29-2.21 (tt, J =
12.2, 6.1 Hz, 2H); Anal. Calcd. for C25H36ClF2N9O4S.1.5H2O: C, 45.6; H, 6.0; Cl, 5.4, N,
19.1; Found: C, 45.5; H, 6.1; Cl, 5.2; N, 19.2%.
4.1.2. 2-[[4-[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-1-piperazinyl]sulfonyl]ethanamine (14)
A mixture of 2-(difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(1-piperazinyl)-
1,3,5-triazin-2-yl]-1H-benzimidazole (12)34 (1.0 g, 2.2 mmol) and DIPEA (0.72 g, 5.5 mmol)
in CH2Cl2 (150 mL) was cooled to -15 °C and 2-chloroethanesulfonyl chloride (0.54 g, 3.3
mmol) was added dropwise over 5 min. The mixture was stirred at 0 °C for 2 h and water was
added. The mixture was filtered to remove a white precipitate, and the CH2Cl2 solution was
dried (Na2SO4), concentrated, and eluted on to a column of silica. Elution with
CH2Cl2/EtOAc (9:1) gave 2-(difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-[4-

(vinylsulfonyl)-1-piperazinyl]-1,3,5-triazin-2-yl]-1H-benzimidazole (13) (0.84 g, 70% yield):
mp (MeOH) 242-244 °C; 1H NMR (CDCl3) δ 7.85 (dd, J = 8.4, 0.7 Hz, 1H), 7.43 (t, JHF =
53.5 Hz, 1H), 7.35 (t, J = 8.2 Hz, 1H), 6.82 (d, J = 7.7 Hz, 1H), 6.43 (dd, J = 16.6, 9.8 Hz,
1H), 6.29 (d, J = 16.6 Hz, 1H), 6.07 (d, J = 9.8 Hz, 1H), 4.05 (s, 3H), 4.01 (m, 4H), 3.87 (m,
4H), 3.78 (m, 4H), 3.26 (m, 4H); MS (APCI) m/z: 536.9 (M+H+); Anal. Calcd. for
C22H26F2N8O4S: C, 49.25; H, 4.9; N, 20.9; Found: C, 49.1; H, 5.0; N, 20.4%.
A mixture of 13 (107 mg, 0.2 mmol) and conc. aqueous NH3 (2 mL) in THF (20 mL)
was heated at 100 °C in a sealed tube for 2 h. The solvents were removed under vacuum and
the resulting residue was recrystallized from MeOH to give 14 (106 mg, 96%): mp 244-
246 °C; 1H NMR (DMSO-d6) δ 7.89 (d, J = 7.9 Hz, 1H), 7.69 (t, JHF = 52.8 Hz, 1H), 7.41 (t,
J = 8.2 Hz, 1H), 6.96 (d, J = 7.8 Hz, 1H), 3.98 (s, 3H), 3.93-3.91 (m, 4H), 3.83-3.80 (m, 4H),
3.71-3.68 (m, 4H), 3.28-3.21 (m, 4H ), 3.14 (t, J = 6.8 Hz, 2H), 2.91 (t, J = 6.8 Hz, 2H); MS
(APCI) m/z: 553.9 (M+H+); Anal. Calcd. for C22H29F2N9O4S.0.06CH2Cl2: C, 47.4; H, 5.25;
N, 22.6; Found: C, 47.3; H, 5.25; N, 22.7%.
4.1.3. 2-[[4-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,
5-triazin-2-yl]-1-piperazinyl]sulfonyl]-N-methylethanamine (15)
A mixture of compound 13 (272 mg, 0.51 mmol) and 40% aq. methylamine (5 mL) in
THF (20 mL) was stirred at 20 °C for 20 h. The mixture was evaporated to dryness and the
residue was chromatographed on SiO2, eluting with CH2Cl2/EtOAc to give 15 (290 mg,
90%). Treatment of a methanolic solution of 15 with methanesulfonic acid gave the
methanesulfonate: mp (MeOH/EtOAc) 236-239 °C; 1H NMR (DMSO-d6) δ 8.45 (br s, 2H),
7.89 (d, J = 8.04 Hz, 1H), 7.70 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d, J =
7.9 Hz, 1H), 3.97 (s, 3H), 3.95 (m, 4H), 3.83 (m, 4H), 3.70 (m, 4H), 3.49-3.45 (m, 2H), 3.53-
3.17 (m, 5H), 2.62 (s, 3H), 2.31 (s, 3H); MS (APCI) m/z: 567.9 (M+H+); Anal. Calcd. for
C24H35F2N9O7S2: C, 43.4; H, 5.32; N, 19.0; Found: C, 43.3; H, 5.3; N, 19.3%.
4.1.4. 2-[[4-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,
5-triazin-2-yl]-1-piperazinyl]sulfonyl]-N,N-dimethylethanamine (16)
A mixture of 13 (0.536 g, 1 mmol) and 40 % aqueous dimethylamine (10 mL) in THF
(200 mL) was warmed gently until a clear solution was obtained. After 15 min the THF was
removed under vacuum, and the residue was diluted with water to give 16 (0.51 g, 83 %
yield): 1H NMR (CDCl3) δ 7.86 (dd, J = 8.4, 0.6 Hz, 1H), 7.45 (t, JHF = 53.5 Hz, 1H), 7.36 (t,
J = 8.2 Hz, 1H), 6.82 (d, J = 7.8 Hz, 1H), 4.05 (s, 3H), 4.00 (m, 4H), 3.89 (m, 4H), 3.79 (m,

4H), 3.39 (m, 4H), 3.11 (dd, J = 8.1, 6.4 Hz, 2H), 2.78 (dd, J = 8.1, 6.4 Hz, 2H), 2.26 (s, 6H).
MS (APCI) m/z: 582.0 (M+H+).
Hydrochloride: mp (MeOH/EtOAc) 222-224 °C; Anal. Calcd. for C24H34ClF2N9O4S: C,
46.6; H, 5.5; N, 20.4; Cl, 5.7; Found: C, 46.3; H, 5.7; N, 20.0; Cl, 5.7%.
Methanesulfonate: mp (MeOH/EtOAc) 211-213 °C; Anal. Calcd. for C25H37F2N9O7S2:
C, 44.3; H, 5.5; N, 18.6; Found: C, 44.5; H, 5.5; N, 18.6%.
4.1.5. 2-[[4-[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-1-piperazinyl]sulfonyl]-N,N-diethylethanamine (17)
A mixture of 13 (107 mg, 0.2 mmol) and N,N-diethylamine (0.4 mL, 4 mmol) in THF
(20 mL) was heated at 100 °C in a sealed tube for 2 h. The clear solution was cooled to room
temperature and the solvent was removed under vacuum. The residue was diluted with water
and extracted with CH2Cl2. The organic layer was dried (Na2SO4), and concentrated under
vacuum. Chromatography on silica, eluting with CH2Cl2/MeOH (100:0 to 98:2), gave 17 (54
mg, 53%).
Methanesulfonate: mp 148-151 ○C; 1H NMR (DMSO-d6) δ 9.32 (br s, 1H), 7.89 (d, J =
8.1 Hz, 1H), 7.70 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d, J = 7.8 Hz, 1H),
3.98 (s, 3H), 3.98-3.95 (m, 4H), 3.84-3.81 (m, 4H), 3.70 (m, 4H), 3.59 (dd, J = 10.0, 5.5 Hz,
2H), 3.44 (m, 2H), 3.36 (m, 4H), 3.22-3.16 (m, 4H), 2.31 (s, 3H), 1.19 (t, J = 7.2 Hz, 6H);
.
MS (APCI) m/z: 610.0 (M+H+); Anal. Calcd. for C27H41F2N9O7S2 0.4H2O: C, 45.5; H, 5.9; N,
17.7; Found: C, 45.5; H, 5.9; N, 17.6%.
4.1.6. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-[[2-(1-pyrrolidinyl)-
ethyl]sulfonyl]-1-piperazinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (18)
A mixture of 13 (150 mg, 0.280 mmol) and pyrrolidine (0.23 mL, 2.80 mmol) in
dioxane (20 mL) was refluxed for 3 h, and the solvent was removed under vacuum. The
residue was diluted with water, and the resulting precipitate was collected and dried.
Chromatography on silica eluting with CH2Cl2/MeOH (98:2), followed by recrystallization
from CH2Cl2/hexanes gave 18 (137 mg, 81%): mp 186-188 ○C; 1H NMR (CDCl3)  7.86 (dd,
J = 8.4, 0.6 Hz, 1H), 7.44 (t, JHF = 53.5 Hz, 1H), 7.35 (t, J = 8.2 Hz, 1H), 6.82 (d, J = 7.6 Hz,
1H), 4.05 (s, 3H), 3.99 (m, 4H), 3.88 (m, 4H), 3.80-3.77 (m, 4H), 3.39 (t, J = 5.0 Hz, 4H),
3.18-3.15 (m, 2H), 2.94-2.91 (m, 2H), 2.54-2.51 (m, 4H), 1.80-1.73 (m, 4H); MS (APCI) m/z:
607.9 (M+H+); Anal. Calcd. for C26H35F2N9O4S: C, 51.4; H, 5.8; N, 20.7; Found: C, 51.3; H,
5.9; N, 20.5%.

4.1.7. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-[[2-(1-piperidinyl)-
ethyl]sulfonyl]-1-piperazinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (19)
A mixture of 13 (150 mg, 0.280 mmol) and piperidine (0.14 mL, 1.42 mmol) in
dioxane (20 mL) was refluxed for 18 h. After cooling to room temperature, the solvents were
removed under vacuum. The residue was partitioned between CH2Cl2 and H2O, and after
drying (Na2SO4), the organic solvent was removed under vacuum. Chromatography on
silica, eluting with CH2Cl2/MeOH (100:0 to 98:2) gave 19 (147 mg, 84%).
Methanesulfonate: mp 250-252 ○C; 1H NMR (DMSO-d6) δ 9.21 (br s, 1H), 7.89 (d, J =
7.9, 1H), 7.70 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d, J = 7.8, 1H), 3.98 (s,
3H), 3.96 (m, 4H), 3.84-3.81 (m, 4H), 3.70 (m, 4H), 3.59 (m, 2H), 3.51-3.43 (m, 4H), 3.35
(m, 4H), 2.97-2.89 (m, 2H), 2.31 (s, 3H), 1.84-1.81 (m, 2H), 1.70-1.54 (m, 3H), 1.38-1.29
(m, 1H); MS (APCI) m/z: 622.0 (M+H+); Anal. Calcd. for C28H41F2N9O7S2: C, 46.85; H, 5.8;
N, 17.6; Found: C, 46.85; H, 5.9; N, 17.3%.
4.1.8. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-[[2-(4-morpholinyl)-
ethyl]sulfonyl]-1-piperazinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (20)
A mixture of 13 (0.536 g, 1 mmol) and morpholine (10 mL) in THF (150 mL) was
heated under reflux for 2 h. The solvent was removed under vacuum and the residue was
diluted with water, to give a solid which was collected by filtration. Drying at 100 °C under
vacuum gave 20 (0.605 g, 97% yield): 1H NMR (CDCl3) δ 7.86 (d, J = 7.9 Hz, 1H), 7.44 (t,
JHF = 53.5 Hz, 1H), 7.36 (t, J = 8.2 Hz, 1H), 6.83 (d, J = 7.8 Hz, 1H), 4.05 (s, 3H), 4.00 (m,
4H), 3.89 (m, 4H), 3.79 (m, 4H), 3.37 (m, 4H) 3.39 (m, 4H), 3.14 (dd, J = 8.3, 6.4 Hz, 2H),
2.84 (dd, J = 8.3, 6.3 Hz, 2H), 2.48 (m, 4H); MS (APCI) m/z: 623.2 (M+H+). Hydrochloride:
mp (MeOH/EtOAc) 209-212 °C; 1H NMR (DMSO-d6) δ 11.49 (br, 1H), 7.89 (d, J = 8.08 Hz,
1H), 7.70 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d, J = 7.88 Hz, 1H), 3.98 (s,
3H), 3.98-3.93 (m, 4H), 3.85-3.79 (m, 4H), 3.78-3.67 (m, 8H), 3.53-3.41 (m, 2H), 3.40-3.30
(m, 8H), 3.19-3.05 (m, 2H). Anal. Calcd. for C26H36ClF2N9O5S.1.2H2O: C, 45.8; H, 5.7; N,
18.5; Cl, 5.2; Found: C, 45.8; H, 5.7; N, 18.3; Cl, 5.2%.
4.1.9. 3-[2-[[4-[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-1-piperazinyl]sulfonyl)ethyl]-8-oxa-3-azabicyclo[3.2.1]octane (21)
A mixture of 13 (150 mg, 0.280 mmol), 8-oxa-3-azabicyclo[3.2.1]octane hydrochloride
(293 mg, 1.96 mmol), and DIPEA (0.49 mL, 2.80 mmol) in dioxane was heated under reflux
for 12 h. The solvent was removed under vacuum, and the residue was diluted with water.

The resulting precipitate was dissolved in CH2Cl2 and dried (Na2SO4). Chromatography on
silica, eluting with CH2Cl2/MeOH (98:2), followed by recrystallization from CH2Cl2/hexanes
to give 21 (118 mg, 87%): mp 219-221 ○C; 1H NMR (CDCl3)  7.85 (dd, J = 8.4, 0.5 Hz,
1H), 7.43 (t, JHF = 53.5 Hz, 1H), 7.36 (t, J = 8.2 Hz, 1H), 6.82 (d, J = 7.7 Hz, 1H), 4.27-4.26
(m, 2H), 4.05 (s, 3H), 4.01 (m, 4H), 3.88 (m, 4H), 3.80-3.77 (m, 4H), 3.38 (t, J = 5.0 Hz, 4H),
3.07 (dd, J = 8.1, 6.3 Hz, 2H), 2.79 (dd, J = 8.1, 6.3 Hz, 2H), 2.55 (d, J = 10.6 Hz, 2H), 2.38
(dd, J = 10.9, 2.0 Hz, 2H), 1.89-1.77 (m, 4H); MS (APCI) m/z: 650.0 (M+H+); Anal. Calcd.
for C28H37F2N9O5S: C, 51.8; H, 5.7; N, 19.4; Found: C, 51.8; H, 5.9; N, 19.3%.
4.1.10. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-[[2-(4-thiomorpholin-
yl)ethyl]sulfonyl]-1-piperazinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (22)
A mixture of 13 (268 mg, 0.5 mmol), thiomorpholine (0.52 g, 5 mmol), and dioxane
(30 mL) was heated under reflux for 2 h. The solvent was removed under vacuum and the
residue was diluted with water. The resulting precipitate was collected, washed with water,
and dried. Chromatography on silica, eluting with CH2Cl2/EtOAc (4:1), gave 22 (0.23 g,
72% yield): mp (CH2Cl2/hexanes) 210-212 ○C; 1H NMR (CDCl3)  7.86 (dd, J = 8.3, 0.5 Hz,
1H), 7.43 (t, JHF = 53.5 Hz, 1H), 7.36 (t, J = 8.2 Hz, 1H), 6.82 (d, J = 7.7 Hz, 1H), 4.05 (s,
3H), 4.00 (br s, 4H), 3.89 (br s, 4H), 3.79 (m, 4H), 3.38 (t, J = 5.1 Hz, 4H), 3.11 (dd, J = 8.3,
6.1 Hz, 2H), 2.87 (dd, J = 8.3, 6.1 Hz, 2H), 2.73 (dd, J = 6.1, 3.8 Hz, 4H), 2.63 (m, 4H); MS
.
(APCI) m/z: 640.3 (M+H+); Anal. Calcd. for C26H35F2N9O4S2 0.5H2O: C, 48.1; H, 5.6; N,
19.4; Found: C, 48.2; H, 5.4; N, 19.3%.
4.1.11. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-[[2-(1-oxido-4-
thiomorpholinyl)ethyl]sulfonyl]-1-piperazinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (23)
A mixture of 13 (200 mg, 0.373 mmol), thiomorpholine 1-oxide trifluoroacetate41 (403
mg, 1.87 mmol), and DIPEA (0.9 mL, 5.22 mmol) was refluxed in dioxane (60 mL) for 2
days. The solvent was removed under vacuum, the residue was diluted with water, and the
resulting precipitate was collected and dried. Chromatography on silica, eluting with
CH2Cl2/MeOH (95:5), followed by recrystallization from CH2Cl2/hexane gave 23 (138 mg,
56% yield): mp 229-231 ○C; 1H NMR (CDCl3)  7.85 (d, J = 8.0 Hz, 1H), 7.43 (t, JHF = 53.5
Hz, 1H), 7.36 (t, J = 8.2 Hz, 1H), 6.82 (d, J = 7.9 Hz, 1H), 4.05 (s, 3H), 4.01 (m, 4H), 3.89
(m, 4H), 3.80-3.78 (m, 4H), 3.38 (t, J = 5.0 Hz, 4H), 3.19-3.10 (m, 4H), 2.99 (dd, J = 8.8, 5.4,
2H), 2.89-2.68 (m, 6H); MS (APCI) m/z: 655.9 (M+H+); Anal. Calcd. for
.
C26H35F2N9O5S2 0.2H2O: C, 47.4; H, 5.4; N, 19.1; Found: C, 47.3; H, 5.5; N, 18.7.

4.1.12. 2-(Difluoromethyl)-1-[4-(4-[[2-(1,1-dioxido-4-thiomorpholinyl)ethyl]sulfonyl]-1-
piperazinyl)-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-4-methoxy-1H-benzimidazole (24)
A solution of KMnO4 (88 mg, 0.559 mmol) in water (6 mL) was added dropwise to a
stirred solution of 22 (170 mg, 0.266 mmol) in acetone (50 mL) and acetic acid (7.5 mL) at
room temperature. After 2.5 h the reaction was diluted with water, decolourized with
Na2SO3, and the acetone was removed under vacuum. The mixture was neutralized with
conc. aq. NH3 to give a precipitate, which was collected and dried. Chromatography on silica,
eluting with CH2Cl2/MeOH (98.5:1.5) gave 24 (117 mg, 65% yield): mp 258-261 °C; 1H
NMR (CDCl3)  7.85 (d, J = 8.3 Hz, 1H), 7.42 (t, JHF = 53.5 Hz, 1H), 7.35 (t, J = 8.2 Hz,
1H), 6.82 (d, J = 8.0 Hz, 1H), 4.05 (s, 3H), 4.01 (m, 4H), 3.88 (m, 4H), 3.80-3.78 (m, 4H),
3.37 (t, J = 5.0 Hz, 4H), 3.09-3.06 (m, 4H), 3.05 (s, 8H); HRMS Calcd. for C26H36F2N9O6S2:
(M+H+) m/z 672.2198; Found: m/z 672.2184.
4.1.13. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-[[2-(4-methyl-1-piperazinyl)ethyl]sulfonyl]-1-
piperazinyl)-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (25)
A mixture of 13 (150 mg, 0.280 mmol) and 1-methylpiperazine (0.32 mL, 2.88 mmol)
in dioxane (20 mL) was heated under reflux for 20 h. The solvent was removed under
vacuum, and the residue was diluted with water, and extracted twice with CH2Cl2.
Chromatography on silica eluting with CH2Cl2/MeOH (100:0 to 95:5) followed by
recrystallization from CH2Cl2/hexanes gave 25 (116 mg, 65%).
Bismethanesulfonate: mp (MeOH/EtOAc) 198-201 ○C; 1H NMR (DMSO-d6) δ 9.52 (br
s, 1H), 7.89 (d, J = 8.1 Hz, 1H), 7.69 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d,
J = 7.9 Hz, 1H), 3.98 (s, 3H), 3.94-3.92 (m, 4H), 3.83-3.81 (m, 4H), 3.70 (m, 4H), 3.44-3.18
(m, 12H), 3.05-2.97 (m, 4H), 2.79 (s, 3H), 2.35 (s, 6H); MS (APCI) m/z: 637.0 (M+H+);
Anal. Calcd. for C29H46F2N10O10S3: C, 42.0; H, 5.6; N, 16.9; Found: C, 42.3; H, 5.6; N,
16.6%.
4.1.14. 2-[4-[2-[[4-[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-
morpholinyl)-1,3,5-triazin-2-yl]-1-piperazinyl]sulfonyl]ethyl]-1-piperazinyl]-1-ethanol (26)
A mixture of 13 (150 mg, 0.280 mmol) and N-(2-hydroxyethyl)piperazine (360 mg,
2.77 mmol) in 1,4-dioxane (15 mL) was refluxed for 3 h. The solvent was removed under
vacuum and the residue was partitioned between CH2Cl2 and H2O. The organic phase was
dried (Na2SO4), and the solvent was removed under vacuum. Recrystallization from
CH2Cl2/hexanes gave 26 (134 mg, 72%).

Bismethanesulfonate: mp (MeOH/EtOAc) 236-238 ○C; 1H NMR (DMSO-d6) δ 9.46 (br
s, 1H), 7.89 (d, J = 8.1 Hz, 1H), 7.69 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d,
J = 7.9 Hz, 1H), 3.98 (s, 3H), 3.95-3.92 (m, 4H), 3.83-3.81 (m, 4H), 3.73-3.70 (m 4H), 3.70-
3.66 (m, 4H), 3.40-3.32 (m, 6H), 3.18 (t, J = 4.9 Hz, 4H), 3.08-2.99 (m, 4H), 2.67 (m, 2H),
.
2.34 (s, 6H); MS (APCI) m/z: 666.9 (M+H+); Anal. Calcd. for C30H48F2N10O11S3 1.5H2O: C,
40.7; H, 5.8; N, 15.8; Found: C, 40.3; H, 5.6; N, 15.8%.
4.1.15. 2-(Difluoromethyl)-4-methoxy-1-[4-[4-[[2-[4-(methylsulfonyl)-1-piperazinyl]ethyl]-
sulfonyl]-1-piperazinyl]-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (27)
A mixture of 13 (0.20 g, 0.37 mmol) and 1-(methylsulfonyl)piperazine (0.31 g, 1.9
mmol) in THF (100 mL) was refluxed for 2 days. The solvent was removed under vacuum,
and the residue was diluted with water to give a white solid, which was collected and dried.
Chromatography on alumina eluting with CH2Cl2/EtOAc (9:1) gave 27 (0.22 g, 84% yield):
1H NMR (CDCl3) δ 7.86 (dd, J = 8.4, 0.6 Hz, 1H), 7.43 (t, JHF = 53.5 Hz, 1H), 7.35 (t, J =
8.2 Hz, 1H), 6.82 (d, J = 7.7 Hz, 1H), 4.05 (s, 3H), 4.01 (m, 4H), 3.88 (m, 4H), 3.79 (m, 4H),
3.38 (m, 4H) 3.23 (m, 4H), 3.11 (dd, J = 8.5, 6.0 Hz, 2H), 2.92 (dd, J = 8.4, 6.0 Hz, 2H),
2.75 (s, 3H), 2.60 (m, 4H).
Methanesulfonate: mp (MeOH/EtOAc) 232-235 °C; 1H NMR (DMSO-d6) δ 9.88 (br,
1H), 7.89 (d, J = 8.0 Hz, 1H), 7.70 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d, J
= 7.96 Hz, 1H), 3.98 (s, 3H), 3.98-3.94 (m, 4H), 3.84-3.89 (m, 4H), 3.73-3.67 (m, 4H), 3.62-
3.41 (m, 12H), 3.39-3.33 (m, 4H), 2.99 (s, 3H), 2.34 (s, 3H). MS (APCI) m/z: 700.9 (M+H+);
.
Anal. Calcd. for C28H42F2N10O9S3 0.5H2O: C, 41.7; H, 5.4; N, 17.4; Found: C, 41.7; H, 5.3;
N, 17.2%.
4.1.16. 2-(Difluoromethyl)-1-[4-(4-[[2-(1H-imidazol-1-yl)ethyl]sulfonyl]-1-piperazinyl)-6-(4-
morpholinyl)-1,3,5-triazin-2-yl]-4-methoxy-1H-benzimidazole (28)
A mixture of 13 (150 mg, 0.280 mmol), imidazole (38 mg, 0.558 mmol), and pyridine
(2 drops) in DMSO (5 mL) was heated at 135-140 ○C for 5 days. The mixture was poured
over ice and extracted with CH2Cl2. The organic extracts were washed with H2O, dried
(Na2SO4), and concentrated. Chromatography on silica, eluting with CH2Cl2/MeOH (100:0 to
95:5), followed by recrystallization from CH2Cl2/hexanes gave 28 (45 mg, 27%): mp 188-191
○C; 1H NMR (CDCl3) δ 7.84 (dd, J = 8.4, 0.6 Hz, 1H), 7.55 (s, 1H), 7.41 (t, JHF = 53.5 Hz,
1H), 7.35 (t, J = 8.2 Hz, 1H), 7.10 (t, J = 1.0 Hz, 1H), 6.96 (t, J = 1.3 Hz, 1H), 6.82 (d, J =
7.7 Hz, 1H), 4.46 (t, J = 7.0 Hz, 2H), 4.05 (s, 3H), 3.94 (m, 4H), 3.87 (m, 4H), 3.79-3.77 (m,

4H), 3.35 (t, J = 7.1 Hz, 2H), 3.29 (m, 4H); MS (APCI) m/z: 604.9 (M+H+); Anal. Calcd. for
C25H30F2N10O4S: C, 49.7; H, 5.0; N, 23.2; Found: C, 49.3; H, 4.9; N, 23.2%.
4.1.17. 3-[[4-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,
3,5-triazin-2-yl]-1-piperazinyl]sulfonyl]-N,N-dimethyl-1-propanamine (32)
A mixture of 4-(4-chloro-6-(2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl)-
1,3,5-triazin-2-yl)morpholine (29)33 (150 mg, 0.378 mmol), N,N-dimethyl-3-(1-
piperazinylsulfonyl)-1-propanamine dihydrochloride (30)38 (151 mg, 0.491 mmol), and
DIPEA (0.40 mL, 2.27 mmol) in DMSO was stirred at room temperature for 30 minutes. The
reaction mixture was diluted with water; and the resulting precipitate was collected and dried.
Chromatography on silica eluting with CH2Cl2/MeOH (95:5), followed by additional
chromatography on silica eluting with CH2Cl2/MeOH (96:4) gave 32 (91 mg, 40%).
Hydrochloride: mp (MeOH/EtOAc) 209-211 ○C; 1H NMR (DMSO-d6)  10.16 (br s,
1H), 7.89 (d, J = 8.4 Hz, 1H), 7.69 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d, J
= 7.8 Hz, 1H), 3.98 (s, 3H), 3.94 (m, 4H), 3.82 (m, 4H), 3.70 (br s, 4H), 3.33 (m, 4H), 3.23
(dd, J = 9.3, 5.8 Hz, 2H), 3.12 (m, 2H), 2.75 (s, 6H), 2.08 (td, J = 15.4, 7.8 Hz, 2H); MS
(APCI) m/z: 596.0 (M+H+); Anal. Calcd. for C25H36ClF2N9O4S.0.5H2O: C, 46.8; H, 5.8; N,
19.7; Found: C, 46.9; H, 5.8; N, 19.4%.
4.1.18. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-[[3-(4-morpholinyl)propyl]-
sulfonyl]-1-piperazinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (33)
A mixture of 29 (150 mg, 0.378 mmol), 4-[3-(1-piperazinylsulfonyl)propyl]morpholine
dihydrochloride (31)38 (172 mg, 0.491 mmol) and DIPEA (0.40 mL, 2.27 mmol) in THF was
stirred at room temperature for 17 h. The solvent was removed under vacuum, and the
residue was diluted with water and extracted with CH2Cl2. Chromatography on silica, eluting
with CH2Cl2/MeOH (98:2) followed by recrystallization from CH2Cl2/hexanes gave 33 (188
mg, 78%).
Methanesulfonate: mp (MeOH/EtOAc) 216-218 ○C; 1H NMR (DMSO-d6)  9.50 (br s,
1H), 7.89 (d, J = 8.2 Hz, 1H), 7.69 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d, J
= 7.8 Hz, 1H), 4.01-3.93 (m, 6H), 3.98 (s, 3H), 3.82 (m, 4H), 3.70 (m, 4H), 3.63 (t, J = 12.1
Hz, 2H), 3.45 (d, J = 12.6 Hz, 2H), 3.32 (m, 4H), 3.21 (t, J = 7.1 Hz, 4H), 3.13-3.06 (m, 2H),
2.30 (s, 3H), 2.14-2.06 (m, 2H); MS (APCI) m/z: 638.0 (M+H+); Anal. Calcd for
C28H41F2N9O8S2: C, 45.8; H, 5.6; N, 17.2; Found: C, 45.7; H, 5.6; N, 17.2%.

4.1.19. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-[4-(3-pyridinylsulfonyl)-1-
piperazinyl]-1,3,5-triazin-2-yl]-1H-benzimidazole (34)
DIPEA (0.78 mL, 4.48 mmol) was added to a mixture of 12 (200 mg, 0.449 mmol) and
3-pyridinesulfonyl chloride (159 mg, 0.859 mmol) in CH2Cl2 (12 mL), and the reaction
mixture was stirred at room temperature overnight under nitrogen. Water was added, and the
organic phase was separated and dried (Na2SO4). Chromatography on silica, eluting with
CH2Cl2/MeOH (99:1) gave 34 (227 mg, 86%).
Methanesulfonate: mp (MeOH/EtOAc) 243-246 ○C; 1H NMR (DMSO-d6) δ 8.94 (dd, J
= 2.2, 0.5 Hz, 1H), 8.88 (dd, J = 4.8, 1.6 Hz, 1H), 8.19 (ddd, J = 8.1, 2.3, 1.7 Hz, 1H), 7.84
(dd, J = 8.4, 0.4 Hz, 1H), 7.68 (ddd, J = 8.1, 4.8, 0.7 Hz, 1H), 7.63 (t, JHF = 52.8 Hz, 1H),
7.39 (t, J = 8.2 Hz, 1H), 6.94 (d, J = 7.8 Hz, 1H), 3.96 (s, 3H), 3.94-3.92 (m, 4H), 3.78-3.76
(m, 4H), 3.66 (m, 4H), 3.11 (m, 4H), 2.33 (s, 3H); MS (APCI) m/z: 587.9 (M+H+); Anal.
Calcd, for C26H31F2N9O7S2: C, 45.7; H, 4.6; N, 18.4; Found: C, 45.6; H, 4.6; N, 18.3%.
4.1.20. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-[[2-(2-pyridinyl)ethyl]-
sulfonyl]-1-piperazinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (35)
DIPEA (0.29 mL, 1.66 mmol) was added to a suspension of 12 (150 mg, 0.336 mmol)
and 2-[2-(chlorosulfonyl)ethyl]pyridine hydrochloride (165 mg, 0.67 mmol) in CH2Cl2 (10
mL) at room temperature under nitrogen, and the mixture was stirred for 24 h. Water was
added and the and the organic phase was separated and dried (Na2SO4). Chromatography on
silica, eluting with CH2Cl2/MeOH (100:0 to 98.5:1.5), gave 35 (148 mg, 71%).
Methanesulfonate: mp (MeOH/EtOAc) 154-157○C; 1H NMR (DMSO-d6) δ 8.64 (d, J =
4.8 Hz, 1H), 8.07 (t, J = 6.9 Hz, 1H), 7.88 (d, J = 8.0 Hz, 1H), 7.69 (t, JHF = 52.9 Hz, 1H),
7.67-7.52 (m, 2H), 7.41 (t, J = 8.2 Hz, 1H), 6.96 (d, J = 7.8 Hz, 1H), 3.98 (s, 3H), 3.92-3.90
(m, 4H), 3.83-3.80 (m, 4H), 3.70 (m, 4H), 3.59 (dd, J = 9.0, 6.7 Hz, 2H), 3.30-3.27 (m, 6H),
.
2.31 (s, 3H); MS (APCI) m/z: 615.9 (M+H+); Anal. Calcd. for C28H35F2N9O7S2 0.7H2O: C,
46.4; H, 5.1; N, 17.4; Found: C, 46.4; H, 5.2; N, 17.6%.
4.1.21. 2-(Difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-[[2-(4-pyridinyl)ethyl]-
sulfonyl]-1-piperazinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole (36)
DIPEA (0.29 mL, 1.66 mmol) was added to a suspension of 12 (150 mg, 0.336 mmol)
and 4-[2-(chlorosulfonyl)ethyl]pyridine hydrochloride (165 mg, 0.67 mmol) in CH2Cl2 (10
mL) at room temperature under nitrogen, and the mixture was stirred for 24 h. Water was
added, and the organic phase was separated and dried (Na2SO4). Chromatography on silica

eluting with CH2Cl2/MeOH (100:0 to 98:2) followed by recrystallization from CH2Cl2/MeOH
gave 36 (134 mg, 65%).
Methanesulfonate: mp (MeOH/EtOAc) 290-293 ○C; 1H NMR (DMSO-d6) δ 8.76 (dd, J
= 5.4, 1.1 Hz, 2H), 7.89-7.87 (m, 3H), 7.69 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H),
6.96 (d, J = 7.8 Hz, 1H), 3.98 (s, 3H), 3.94-3.91 (m, 4H), 3.83-3.81 (m, 4H), 3.70 (m, 4H),
3.59 (dd, J = 8.8, 6.8 Hz, 2H), 3.30-3.23 (m, 6H), 2.31 (s, 3H); MS (APCI) m/z: 615.9
(M+H+); Anal. Calcd. for C28H35F2N9O7S2: C, 47.25; H, 5.0; N, 17.7; Found: C, 47.1; H, 5.0;
N, 17.6%.
4.1.22. 2-[[4-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,
3,5-triazin-2-yl]-1-piperidinyl]sulfonyl]-N,N-dimethylethanamine (49)
To a mixture of 2-(difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-piperidinyl)-
1,3,5-triazin-2-yl]-1H-benzimidazole (37)34 (0.891 mg, 2 mmol) and DIPEA (0.77 g, 6
mmol) in CH2Cl2 (100 mL) was added dropwise 2-chloroethanesulfonyl chloride (0.49 g, 3
mmol) at 0 °C, and the reaction mixture was stirred at that temperature for an additional 2 h.
The reaction mixture was quenched with water (100 mL), and the organic layer was washed
successively with aq. HOAc (1%, 100 mL) and aqueous NH3, and dried. Chromatography on
silica eluting with CH2Cl2/EtOAc (9:1) gave 2-(difluoromethyl)-4-methoxy-1-[4-(4-
morpholinyl)-6-[1-(vinylsulfonyl)-4-piperidinyl]-1,3,5-triazin-2-yl]-1H-benzimidazole (43)
(0.589 g, 55% yield): mp (MeOH) 229-232 °C; 1H NMR (CDCl3) δ 7.99 (dd, J = 8.4, 0.7 Hz,
1H), 7.54 (t, JHF = 53.6 Hz, 1H), 7.39 (t, J = 8.3 Hz, 1H), 6.85 (d, J = 7.6 Hz, 1H), 6.47 (dd,
J = 16.6, 9.9 Hz, 1H), 6.27 (d, J = 16.6 Hz, 1H), 6.05 (d, J = 9.9 Hz, 1H), 4.06 (s, 3H), 4.00-
3.97 (m, 4H), 3.89-3.79 (m, 6H), 2.78 (m, 3H), 2.17 (br dd, J = 13.6, 3.0 Hz, 2H), 2.01 (ddd,
J = 25.2, 11.7, 4.1 Hz, 2H); MS (APCI) m/z: 536.2 (M+H+); Anal. Calcd. for
C23H27F2N7O4S: C, 51.6; H, 5.1; N, 18.3; Found: C, 51.7; H, 5.2; N, 18.25%.
A mixture of 43 (59 mg, 0.11 mmol) and 40% aqueous dimethylamine (5 mL) in THF
(25 mL) was stirred at room temperature for 15 min. The solvent was removed under vacuum
and the residue was diluted with water, to give 49 (63 mg, 99% yield): 1H NMR (CDCl3) δ
7.99 (d, J = 7.9 Hz, 1H), 7.55 (t, JHF = 53.6 Hz, 1H), 7.39 (t, J = 8.3 Hz, 1H), 6.85 (d, J =
7.9 Hz, 1H), 4.06 (s, 3H), 4.02 - 3.89 (m, 6H), 3.85 - 3.78 (m, 4H), 3.14-3.11 (m, 2H), 2.97
(dt, J = 12.2, 2.6 Hz, 2H), 2.84-2.77 (m, 3H), 2.28 (s, 6H), 2.17 (br dd, J = 13.2, 2.6 Hz, 2H),
2.00 (ddd, J = 25.1, 11.8, 4.1 Hz, 2H).
Hydrochloride: mp (MeOH/EtOAc) 243-245 °C; MS (APCI) m/z: 580.9 (M+H+); Anal.
Calcd. for C25H35ClF2N8O4S: C, 48.7; H, 5.7; N, 18.2; Cl, 5.7; Found: C, 48.7; H,5.7; N,

18.0; Cl, 5.7%.
4.1.23. N-[1-[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-3-azetidinyl]-2-(dimethylamino)ethanesulfonamide (50)
To a solution of 1-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-
morpholinyl)-1,3,5-triazin-2-yl]-3-azetidinamine (38)34 (1.04 g, 2.42 mmol) and DIPEA
(0.85 mL, 9.7 mmol) in CH2Cl2 (30 mL) at -10 °C was added 2-chloroethanesulfonyl chloride
(0.5 mL, excess). The stirred mixture was allowed to warm to 20 °C and then diluted with
water. The organic layer was separated and the aqueous layer was further extracted with
CH2Cl2. The combined organic fractions were washed with aq. HOAc and then with aq.
K2CO3, and dried (Na2SO4). Evaporation of the solvents and the chromatography of the
residue on SiO2, eluting with CH2Cl2/EtOAc (0-30%) gave N-[1-[4-[2-(difluoromethyl)-4-
methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-3-
azetidinyl]ethenesulfonamide (44) (123 mg, 9.7% yield): mp (CH2Cl2/MeOH) 250-252 °C;
1H NMR (DMSO-d6) δ 8.20 (br, 1H), 7.96 (dd, J = 7.9, 0.6 Hz, 1H), 7.72 (t, JHF = 53.0 Hz,
1H), 7.40 (t, J = 8.2 Hz, 1H), 6.95 (d, J = 7.8 Hz, 1H), 6.82 (dd, J = 16.5, 10.0 Hz, 1H), 6.08
(dd, J = 26.8, 13.2 Hz, 2H), 4.47 (t, J = 7.6 Hz, 1H), 4.37 (t, J = 8.1 Hz, 1H), 4.26-4.20 (m,
1H), 4.04-3.97 (m, 2H), 3.97 (s, 3H), 3.80-3.77 (m, 4H), 3.68 (m, 4H); MS (APCI) m/z: 523.2
(M+H+); Anal. Calcd. for C21H24F2N8O4S; C, 48.3; H, 4.6; N, 21.4; Found: C, 48.4; H, 4.7;
N, 21.6%.
A mixture of 44 (110 mg, 0.21 mmol) and 40% aqueous dimethylamine (3 mL) in
THF (15 mL) was stirred overnight at 20 °C. The reaction mixture was evaporated to dryness
and the residue was triturated with water to give 50 (112 mg, 93% yield).
Hydrochloride: mp (MeOH) 214-216 °C; 1H NMR (DMSO-d6) δ 10.25 (br s, 1H,
exchangeable with D2O), 8.45 (d, J = 7.40 Hz, 1H), 7.98 (d, J = 8.41 Hz, 1H), 7.74 (t, JHF =
53.0 Hz, 1H), 7.40 (t, J = 8.2 Hz, 1H), 6.95 (d, J = 7.7 Hz, 1H), 4.55-4.36 (m, 3H), 4.15-4.00
(m, 2H), 3.97 (s, 3H), 3.97-3.98 (m, 4H), 3.69 (m, 4H), 3.62-3.59 (m, 2H), 3.41-3.38 (m, 2H),
2.80 (s, 6H); MS (APCI) m/z: 568.0 (M+H+); Anal. Calcd. for C23H32ClF2N9O4S.0.25H2O: C,
45.4; H, 5.4; Cl, 6.2; N, 20.7; Found: C, 45.4; H, 5.2; Cl; 6.0; N, 20.8%.
4.1.24. N-[1-[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-3-azetidinyl]-2-(dimethylamino)-N-methylethanesulfonamide (51)
To a solution of of tert-butyl 1-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-

1-yl]-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-3-azetidinylcarbamate34 (842 mg, 1.58 mmol) in
DMF (5 mL) at 0 °C was added NaH (76 mg, 3.17 mmol), and the mixture was stirred for 30
min. MeI (0.5 mL, excess) was added and the mixture was stirred for an additional 1h, before
being diluted with water. The resulting precipitate was collected by filtration, washed with
water and dried. Chromatography on SiO2, eluting with CH2Cl2/EtOAc (0-15%) gave tert-
butyl 1-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,5-
triazin-2-yl]-3-azetidinyl(methyl)carbamate (823 mg, 95%): mp (CH2Cl2/MeOH) 186-
188 °C; 1H NMR (DMSO-d6) δ 8.00 (d, J = 8.3 Hz, 1H), 7.75 (t, JHF = 53.0 Hz, 1H), 7.39 (t,
J = 8.2 Hz, 1H), 6.95 (d, J = 8.0 Hz, 1H), 4.88 (br, 1H), 4.40-4.15 (m, 4H), 3.97 (s, 3H),
3.80-3.78 (m, 4H), 3.69 (m, 4H), 2.89 (s, 3H), 1.41 (s, 9H); Anal. Calcd. for C25H32F2N8O4:
C, 54.9; H, 5.9; N, 20.5; Found: C, 55.1; H, 5.9; N, 20.6%.
A solution of the above carbamate (760 mg, 1.39 mmol) in CH2Cl2 (10 mL) was
treated with TFA (10 mL) and stirred at 20 °C for 1h. The solvent and excess TFA were
remoced under vacuum, and the resulting residue was stirred with aq NH3. The solid was
collected by filtration, washed with water, and dried, to give 1-[4-[2-(difluoromethyl)-4-
methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-N-methyl-3-
azetidinamine (39) in 96% yield: mp (CH2Cl2/hexanes) 199-201°C; 1H NMR (DMSO-d6) δ
7.99 (dd, J = 8.4, 0.5 Hz, 1H), 7.75 (t, JHF = 53.1Hz, 1H), 7.40 (t, J = 8.2 Hz, 1H), 6.95 (d, J
= 7.8 Hz, 1H), 4.30-4.20 (m, 2H), 3.97 (s, 3H), 3.89-3.85 (m, 1H), 3.80-3.77 (m, 5H), 3.70-
3.68 (m, 4H), 3.64-3.58 (m, 1H), 2.26 (s, 3H).
To a solution of 39 (580 mg, 1.3 mmol) and DIPEA (0.8 mL) in CH2Cl2 (10 mL) at -
10 °C was added 2-chloroethanesulfonyl chloride (0.6 mL, excess) and the reaction mixture
was stirred for an additional 1h, with warming to 20 °C. Dilution with water, and removal of
the CH2Cl2 gave a soild which was collected by filtration, washed with water, and died.
Chromatography on SiO2, eluting with CH2Cl2/EtOAc (0-12.5%) gave N-[1-[4-[2-
(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-3-
azetidinyl]-N-methylethenesulfonamide (45) (305 mg, 44%): mp (CH2Cl2/MeOH) 244-
246 °C; 1H NMR (DMSO-d6) δ 7.98 (d, J = 8.4 Hz, 1H), 7.74 (t, JHF = 53.0 Hz, 1H), 7.40 (t,
J = 8.2 Hz, 1H), 6.95 (d, J = 7.8 Hz, 1H), 6.86 (dd, J = 16.5, 10.0 Hz, 1H), 6.17 (dd, J =
13.2, 7.7 Hz, 2H), 4.74-4.67 (m, 1H), 4,22-4.20 (m, 4H), 3.98 (s, 3H), 3.80-3.78 (m, 4H),
3.68 (m, 4H), 2.86 (s, 3H); MS (APCI) m/z: 537.2 (M+H+); Anal. Calcd. for C22H26F2N8O4S:
C, 49.3; H, 4.9; N, 20.9; Found: C, 49.3; H, 4.9; 20.9%.
To a suspension of 45 (280 mg, 0.52 mmol) in THF (20 mL) was added 40% aqueous
dimethylamine (5 mL) and the mixture was heated at 70 °C for 1h, and cooled to 20 °C. The

volatiles were removed, and the residue was diluted with water. The resulting precipitate was
collected by filtration, washed with water and dried. Chromatography on SiO2, eluting with
CH2Cl2/EtOAc (0-20%) gave 51 (309 mg, 88%).
Methanesulfonate: mp (CH2Cl2/MeOH/EtOAc) 239-242°C; 1H NMR (DMSO-d6) δ
9.44 (br, 1H, exchangeable with D2O), 7.99 (dd, J = 8.4, 0.5 Hz, 1H), 7.75 (t, JHF = 53.0 Hz,
1H), 7.40 (t, J = 8.2 Hz, 1H), 6.96 (d, J = 7.7 Hz, 1H), 4.88-4.81 (m, 1H), 4.49-4.29 (m, 4H),
3.98 (s, 3H), 3.82-3.79 (m, 4H), 3.69 (m, 4H), 3.60-3.56 (m, 2H), 3.46-3.43 (m, 2H), 3.01 (s,
3H), 2.86 (s, 6H), 2.30 (s, 3H); MS (APCI) m/z: 581.9 (M+H+); Anal. Calcd. for
.
C25H37F2N9O7S2 0.75H2O: C, 43.4; H, 5.6; N, 18.2; Found: C, 43.4; H, 5.5; N, 17.9%.
4.1.25. N-[1-[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-4-piperidinyl]-2-(dimethylamino)ethanesulfonamide (52)
Reaction of 1-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-
morpholinyl)-1,3,5-triazin-2-yl]-4-piperidinamine (40)34 with 2-chloroethanesulfonyl
chloride, as in previous examples, gave N-[1-[4-[2-(difluoromethyl)-4-methoxy-1H-
benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-4-piperidinyl]ethenesulfonamide
(46) in 42% yield: mp (CH2Cl2/MeOH) 221-224 °C; 1H NMR (DMSO-d6) δ 7.87 (dd, J = 7.9,
0.6 Hz, 1H), 7.68 (t, JHF = 52.9 Hz, 1H), 7.45 (br s, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.95 (d, J =
7.8 Hz, 1H), 6.79 (dd, J = 16.5, 9.9 Hz, 1H), 6.07 (d, J = 16.5 Hz, 1H), 5.96 (d, J = 9.9 Hz,
1H), 4.46 (t, J = 17.0 Hz, 1H), 9.98 (s, 3H), 3.81-3.78 (m, 4H), 3.70-3.69 (m, 4H), 3.41-3.32
(m, 4H), 1.92 (br s, 2H), 1.44-1.42 (m, 2H); MS (APCI) m/z: 551.2 (M+H+); Anal. Calcd. for
C23H28F2N8O4S: C, 50.2; H, 5.1; N, 20.3; Found: C, 50.3; H, 5.1; N, 20.5%.
A solution of 46 (251 mg, 0.46 mmol) in THF (15 mL) was treated with 40% aqueous
dimethylamine (5 mL, excess) and the mixture was stirred at 20 °C for 1 h. After dilution
with water the volatiles were removed, and the resulting precipitate was collected, washed
with water, and dried. Chromatography on SiO2, eluting with CH2Cl2/EtOAc (0-20%), then
CH2Cl2/MeOH (3%) gave 52 (188 mg, 65%).
Hydrochloride: mp (MeOH) 236-239 °C; 1H NMR (DMSO-d6) δ 10.31 (br s, 1H), 7.88
(dd, J = 8.4, 0.4 Hz, 1H), 7.69 (t, JHF = 52.9 Hz, 1H), 7.65 (d, J = 7.5 Hz, 1H), 7.41 (t, J =
8.2 Hz, 1H), 6.95 (d, J = 7.8 Hz, 1H), 4.52 (t, J = 16.8 Hz, 2H), 3.98 (s, 3H), 3.82-3.79 (m,
4H), 3.71-3.69 (m, 4H), 3.62-3.49 (m, 3H), 3.40-3.36 (m, 2H), 3.25-3.24 (m, 2H), 2.81 (s,
6H), 2.00 (br, 2H), 1.50-1.45 (m, 2H); MS (APCI) m/z: 596.0 (M+H+); Anal. Calcd. for
C21H36ClF2N9O4S: C, 47.5; H, 5.7; N. 19.9; Cl, 5.6; Found: C, 47.6; H, 5.8; N, 20.1; Cl,
5.9%.

4.1.26. N-[1-[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-4-piperidinyl]-2-(dimethylamino)-N-methylethanesulfonamide (53)
A mixture of 29 (873 mg, 2.2 mmol), tert-butyl methyl(4-piperidinyl)carbamate (566
mg, 2.64 mmol), and DIPEA (1.1 mL, 4.2 mmol) in THF (25 mL) was stirred at 20 °C for 20
h. The solvent was removed under vacuum and the residue was stirred in aq. HOAc, resulting
in a precipitate which was collected, washed with water, and dried. Recrystallization from
CH2Cl2/MeOH gave tert-butyl 1-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-
6-(4-morpholinyl)-1,3,5-triazin-2-yl]-4-piperidinyl(methyl)carbamate (1.18 g, 93%): mp
(CH2Cl2/MeOH) 182-184 °C; 1H NMR (DMSO-d6) δ 7.89 (d, J = 7.9 Hz, 1H), 7.69 (t, JHF =
52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.95 (d, J = 7.8 Hz, 1H), 4.83-4.72 (m, 2H), 4.09 (br,
1H), 3,98 (s, 3H), 3.81-3.79 (m, 4H), 3,70-3.69 (m, 4H), 3.07-2.93 (m, 2H), 2.66 (s, 3H), 1.66
(m, 4H), 1.41 (s, 9H); Anal. Calcd. for C27H36F2N8O4: C, 56.4; H, 6.3; N, 19.7; Found: C,
56.6; H, 6.3; N, 19.8%.
A solution of the above carbamate (1.1 g, 1.91 mmol) in CH2Cl2 (20 mL) was treated
with TFA (10 mL) and stirred for 2 h. The reaction mixture was carefully poured into a
mixture of ice/aq NH3, and stirred for 10 min. The organic layer was separated, washed with
water, and dried (Na2SO4), to give 1-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-
yl]-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-N-methyl-4-piperidinamine (41) (677 mg, 65%) in
96% yield: 1H NMR (DMSO-d6) δ 7.89 (dd, J = 8.3, 0.5 Hz, 1H), 7.68 (t, JHF = 52.9 Hz, 1H),
7.40 (t, J = 8.2 Hz, 1H), 6.94 (d, J = 7.7 Hz, 1H), 4.42 (t, J = 14.2 Hz, 1H), 3.98 (s, 3H),
3.80-3.78 (m, 4H), 3.70-3.69 (m, 4H), 3.36-3.18 (m, 2H), 2.62-2.54 (m, 1H), 2.30 (s,
3H),1.89 (br, 2H), 1.64 (br, 1H), 1.24 (br, 2H).
A solution of 41 (875 mg, 1.84 mmol) and DIPEA (0.64 mL, 3.68 mmol) in CH2Cl2
(30 mL) at -10°C was treated with chloroethanesulfonyl chloride (1 mL, excess). The
reaction mixture was stirred for 1h, and allowed to warm to 20 °C. After dilution with water
(50 mL), the organic layer was seperated, and the aq layer was futher extracted with CH2Cl2.
The combined organic fractions were dried (Na2SO4), and the solvent was removed.
Chromatography on SiO2, eluting with CH2Cl2/EtOAc (0-10%) gave
N-[1-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-1,3,5-
triazin-2-yl]-4-piperidinyl]-N-methylethenesulfonamide (47) (677 mg, 65%): mp
(CH2Cl2/MeOH) 223-225 °C; 1H NMR (DMSO-d6) δ 7.88 (d, J = 8.0 Hz, 1H), 7.68 (t, JHF =
52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.95 (d, J = 7.9 Hz, 1H), 6.85 (dd, J = 16.4, 10.0 Hz,
1H), 6.07 (dd, J = 15.2, 13.2 Hz, 2H), 4.82-4.70 (m, 2H), 3.98 (s, 3H), 3.95-3.88 (m, 1H),
3.81-3.79 (m, 4H), 3.70-3.69 (m, 4H), 3.10-2.97 (m, 2H), 2.62 (s, 3H), 1.72 (m, 4H); MS

(APCI) m/z: 565.2 (M+H+); Anal. Calcd. for C24H30F2N8O4S: C, 51.1; H, 5.4; N, 19.9;
Found: C, 50.8; H, 5.3; N, 19.9%.
A solution of 47 (336 mg, 0.59 mmol) in THF (15 mL) was treated with 40% aqueous
dimethylamine (5 mL, excess) and the reaction mixture was stirred for 2h at 20 °C. The
volatiles were removed, and the resulting precipitate was collected, washed with water, and
diried. Chromatography on SiO2, eluting with CH2Cl2/EtOAc (0-20%), followed by
CH2Cl2/MeOH (3%) gave 53 (356 mg, 93%).
Hydrochloride: mp (MeOH) 242-245 °C; 1H NMR (DMSO-d6) δ 10.47 (br, 1H, N+H),
7.89 (d, J = 8.0 Hz, 1H), 7.69 (t, JHF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.95 (d, J =
7.8 Hz, 1H), 4.84-4.74 (m, 2H), 3.98 (s, 3H), 3.98-3.91 (m, 1H), 3.82-3.80 (m, 4H), 3.70-3.63
(m, 6H), 3.40-3.36 (m, 2H), 3.14-3.00 (m, 2H), 2.81(s. 6H), 2.75 (s, 3H), 1.78 (m, 4H); MS
(APCI) m/z: 610.0 (M+H+); Anal. Calcd. for C26H38ClF2N9O4S.0.25H2O: C, 48.0; H, 6.0; Cl,
5.5; N, 19.4; Found: C; 48.0; H, 6.1; Cl. 5.7; N, 19.5%.
4.1.27. 2-[[4-[[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]oxy]-1-piperidinyl]sulfonyl]-N,N-dimethylethanamine (54)
To a solution of 2-(difluoromethyl)-4-methoxy-1-[4-(4-morpholinyl)-6-(4-
piperidinyloxy)-1,3,5-triazin-2-yl]-1H-benzimidazole (42)34 (1.52 g, 3.29 mmol) and DIPEA
(2.3 ml, 4 eq.) in CH2Cl2 (30 mL) at 0 °C was added 2-chloroethanesulfonyl chloride (1 mL,
excess). The reaction mixture was stirred at 20 °C for 20 h and diluted with water (50 mL).
The organic fraction was washed successively with aq. HOAc, aq. K2CO3, and water, and
dried (MgSO4). Chromatography on silica, eluting with CH2Cl2/EtOAc (9:1) gave 2-
(difluoromethyl)-4-methoxy-1-(4-(4-morpholinyl)-6-[[1-(vinylsulfonyl)-4-piperidinyl]oxy]-
1,3,5-triazin-2-yl)-1H-benzimidazole (48) (1.17 g, 65% yield): mp (CH2Cl2/MeOH) 266-
269 °C; 1H NMR (DMSO-d6)  7.95 (d, J = 7.9 Hz, 1H), 7.70 (t, J HF = 52.8 Hz, 1H), 7.44 (t,
J = 8.2 Hz, 1H), 6.98 (d, J = 7.8 Hz, 1H), 6.88 (dd, J = 16.5, 10.0 Hz, 1H), 6.19 (d, J = 10.0
Hz, 1H), 6.15 (d, J = 16.5 Hz, 1H), 5.26-5.20 (m, 1H), 3.98 (s, 3H), 3.84 (m, 4H), 3.74-3.32
(m, 4H), 3.39-3.32 (m, 2H), 3.14-3.08 (m, 2H), 2.14-2.09 (m, 2H), 1.90-1.18 (m, 2H); Anal.
Calcd. for C23H27F2N7O5S.0.5CH2Cl2: C, 47.7; H, 4.7; N, 16.5; Found: C, 47.8; H, 4.7; N,
16.8%.
To a suspension of 48 (207 mg, 0.38 mmol) in THF (25 mL) was added 40% aq.
dimethylamine (5 mL, excess) and the reaction mixture was stirred at 20 °C for 20 h. The
solvent was evaporated and the residue was diluted with H2O (50 mL), to give a precipitate
which was collected and dried. Chromatography on silica, eluting with CH2Cl2/MeOH (97:3)

gave 54 (210 mg, 97% yield).
Hydrochloride: mp (MeOH), 264-268 °C; 1H NMR (DMSO-d6)  10.20 (br s, 1H), 7.96
(d, J = 7.9 Hz, 1H), 7.72 (t, J HF = 52.8 Hz, 1H), 7.45 (t, J = 8.3 Hz, 1H), 6.99 (d, J = 7.8 Hz,
1H), 5.30-5.24 (m, 1H), 3.90 (s, 3H), 3.86-3.83 (m, 4H), 3.74-3.71 (m, 4H), 3.64-3.60 (m,
2H), 3.54-3.49 (m, 2H), 3.42-3.39 (m, 2H), 3.32-3.24 (m, 2H), 2.80 (s, 6H), 2.16-2.09 (m.
2H), 1.92-1.84 (m, 2H); MS (APCI) m/z: 597.0 (M+H+); Anal. Calcd. for C25H35ClF2N8O5S:
C, 47.3; H, 5.6; N, 17.7; Cl, 5.6; Found: C, 47.4; H, 5.7; N, 17.8; Cl, 5.7%.
4.1.28. N-[1-[4-[2-(Difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-4-piperidinyl]-N-[3-(dimethylamino)propyl]methanesulfonamide (57)
To a mixture of N-[1-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-
morpholinyl)-1,3,5-triazin-2-yl]-4-piperidinyl]methanesulfonamide (55)34 (1.95 g, 3.62
mmol) and K2CO3 (6 g, excess) in DMF ( 20 mL) was added 3-bromo-1-propanol (4 mL,
excess). The reaction mixture was stirred at 20 °C for 7 days and diluted with water. The
resulting sticky material was extracted into CH2Cl2 and dried (Na2SO4). Chromatography on
silica, eluting with a gradient of CH2Cl2/EtOAc (0-20%) followed by CH2Cl2/MeOH (97:3)
gave N-[1-[4-[2-(difluoromethyl)-4-methoxy-1H-benzimidazol-1-yl]-6-(4-morpholinyl)-
1,3,5-triazin-2-yl]-4-piperidinyl]-N-(3-hydroxypropyl)methanesulfonamide (56) (1.04 g,
49%): mp (CH2Cl2/MeOH) 219-221 °C; 1H NMR (DMSO-d6)  7.89 (d, J = 8.2 Hz, 1H),
7.69 (t, J HF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.95 (d, J = 7.9 Hz, 1H), 4.73 (d, J =
12.8 Hz, 1H), 4.82 (d, J = 12.3 Hz, 1H), 4.44 (t, J = 5.1 Hz, 1H), 3.97 (S, 3H), 3.92-3.83 (m,
1H), 3.80-3.79 (m, 4H), 3.69 (m, 4H), 3.40-3.32 (m, 2H), 3.14-2.96 (m, 4H), 3.96 (s, 3H),
1.87-1.80 (m, 2H), 1.74-1.64 (m, 4H); MS (APCI) m/z: 597.3 (M+H+); Anal Calcd. for
C25H34F2N8O5S :C, 50.33; H, 5.74; N, 18.78; Found: C, 50.2; H, 5.9; N, 18.5%.
A solution of 56 (305 mg, 0.51 mmol) and Et3N (0.3 mL) in CH2Cl2 (15 mL) at 0 °C
was treated with methanesulfonyl chloride (0.2 mL, 2.5 mmol). The reaction mixture was
stirred at 0 °C for 45 min and a solution of 40% aqueous dimethylamine (5 mL) was then
added. Stirring was continued for 2 days at 20 °C, and the CH2Cl2 was evaporated. The
residue was diluted with water, and the resulting precipitate was collected and dried.
Chromatography on neutral alumina, eluting with CH2Cl2/MeOH (98:2), followed by
chromatography on silica, eluting with CH2Cl2/MeOH/aq. NH3 (96:3:1) gave 57 (200 mg,
63%).
Hydrochloride: mp (MeOH/i-PrOH) 187-191 °C; 1H NMR (DMSO-d6)  9.83 (br s,
1H), 7.89 (d, J = 8.0 Hz, 1H), 7.70 (t, J HF = 52.9 Hz, 1H), 7.41 (t, J = 8.2 Hz, 1H), 6.95 (d, J