Benzoxazolinone aryl sulfonamides as potent, selective Nav1.7 inhibitors with in vivo efficacy in a preclinical pain model

Article abstract of DOI:10.1016/j.bmcl.2017.04.040

Studies on human genetics have suggested that inhibitors of the Na_v1.7 voltage-gated sodium channel hold considerable promise as therapies for the treatment of chronic pain syndromes. Herein, we report novel, peripherally-restricted benzoxazoli

Full text of DOI:10.1016/j.bmcl.2017.04.040

Accepted Manuscript
Benzoxazolinone aryl sulfonamides as potent, selective Nav1.7 inhibitors with
in vivo efficacy in a preclinical pain model
Joseph E. Pero, Michael A. Rossi, Hannah D.G.F. Lehman, Michael J. Kelly III,
James J. Mulhearn, Scott E. Wolkenberg, Matthew J. Cato, Michelle K.
Clements, Christopher J. Daley, Tracey Filzen, Eleftheria N. Finger, Yun
Gregan, Darrell A. Henze, Aneta Jovanovska, Rebecca Klein, Richard L. Kraus,
Yuxing Li, Annie Liang, John M. Majercak, Jacqueline Panigel, Mark O. Urban,
Jixin Wang, Ying-Hong Wang, Andrea K. Houghton, Mark E. Layton
PII:
S0960-894X(17)30417-1
DOI:
http://dx.doi.org/10.1016/j.bmcl.2017.04.040
BMCL 24893
Reference:
Bioorganic & Medicinal Chemistry Letters
To appear in:
Received Date:
Revised Date:
Accepted Date:
31 January 2017
11 April 2017
12 April 2017
Please cite this article as: Pero, J.E., Rossi, M.A., D.G.F. Lehman, H., Kelly, M.J. III, Mulhearn, J.J., Wolkenberg,
S.E., Cato, M.J., Clements, M.K., Daley, C.J., Filzen, T., Finger, E.N., Gregan, Y., Henze, D.A., Jovanovska, A.,
Klein, R., Kraus, R.L., Li, Y., Liang, A., Majercak, J.M., Panigel, J., Urban, M.O., Wang, J., Wang, Y-H., Houghton,
A.K., Layton, M.E., Benzoxazolinone aryl sulfonamides as potent, selective Nav1.7 inhibitors with in vivo efficacy
in a preclinical pain model, Bioorganic & Medicinal Chemistry Letters (2017), doi: http://dx.doi.org/10.1016/j.bmcl.
2017.04.040
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Benzoxazolinone aryl sulfonamides as
potent, selective Nav1.7 inhibitors with in
vivo efficacy in a preclinical pain model
Leave this area blank for abstract info.
Joseph E. Peroa,∗, Michael A. Rossia, Hannah D.G.F. Lehmana, Michael J. Kelly IIIa, James J. Mulhearna, Scott
E. Wolkenberga, Matthew J. Catob, Michelle K. Clementsc, Christopher J. Daleyb, Tracey Filzenb, Eleftheria N.
Fingerb, Yun Greganb, Darrell A. Henzec, Aneta Jovanovskab, Rebecca Kleinc, Richard L. Krausb, Yuxing Lib,
Annie Liangd, John M. Majercakb, Jacqueline Panigelc, Mark O. Urband, Jixin Wangc, Ying-Hong Wange,
Andrea K. Houghtonb, and Mark E. Laytona

Bioorganic & Medicinal Chemistry Letters
journal homepage: www.els evier.com
Benzoxazolinone aryl sulfonamides as potent, selective Nav1.7 inhibitors with in
vivo efficacy in a preclinical pain model
Joseph E. Pero a,∗, Michael A. Rossia, Hannah D.G.F. Lehmana, Michael J. Kelly IIIa, James J. Mulhearna,
Scott E. Wolkenberga, Matthew J. Catob, Michelle K. Clementsc, Christopher J. Daleyb, Tracey Filzenb,
Eleftheria N. Fingerb, Yun Greganb, Darrell A. Henzec, Aneta Jovanovskab, Rebecca Kleinc, Richard L.
Krausb, Yuxing Lib, Annie Liangd, John M. Majercakb, Jacqueline Panigelc, Mark O. Urband, Jixin Wangc,
Ying-Hong Wange, Andrea K. Houghtonb, and Mark E. Laytona
aDepartments of aMedicinal chemistry, bIn vitro pharmacology, cNeuroscience, dIn vivo pharmacology,eDrug metabolism and pharmacokinetics
Merck & Co., Inc., West Point, PA 19486, USA
ARTICLE INFO
ABSTRACT
Article history:
Received
Studies on human genetics have suggested that inhibitors of the Nav1.7 voltage-gated sodium
channel hold considerable promise as therapies for the treatment of chronic pain syndromes.
Herein, we report novel, peripherally-restricted benzoxazolinone aryl sulfonamides as potent
Nav1.7 inhibitors with excellent selectivity against the Nav1.5 isoform, which is expressed in the
heart muscle. Elaboration of initial lead compound 3d afforded exemplar 13, which featured
attractive physicochemical properties, outstanding lipophilic ligand efficiency and
pharmacological selectivity against Nav1.5 exceeding 1,000-fold. Key structure-activity
relationships associated with oral bioavailability were leveraged to discover compound 17,
which exhibited a comparable potency/selectivity profile as well as full efficacy following oral
administration in a preclinical model indicative of antinociceptive behavior.
Revised
Accepted
Available online
Keywords:
chronic pain
voltage-gated sodium channel
NaV1.7 inhibition
pharmacological selectivity
oral bioavailability
2017 Elsevier Ltd. All rights reserved
.
———
∗ Corresponding author. e-mail: joseph.e.pero@gsk.com; tel.: +1-610-270-6515; fax: +1-610-270-4074; current address: 709 Swedeland Road,
UW 2412, King of Prussia, PA 19406, USA.

Despite many years of intense research, the development of
safe and effective therapeutics for the treatment of chronic pain
remains an unmet medical need. Recent epidemiological studies
have found that 10-55% of people in various countries suffer
from chronic pain.1 In the United States alone, approximately
35% of the population lives with chronic pain syndromes, with
roughly 50 million Americans experiencing partial or total
disability as a consequence. Furthermore, chronic pain is
associated with an increased prevalence of other disorders such
as depression, anxiety, insomnia and weight gain.2,3 In addition,
severe chronic pain has been linked to elevated mortality rates,
particularly from heart and respiratory diseases.4
considerable interest from the pharmaceutical industry. To this
end, Pfizer has disclosed a series of arylsulfonamide Nav1.7
inhibitors exemplified by PF-05089771 (1a, Figure 1)14 with
high (>1,000-fold) pharmacological selectivity over Nav1.5. The
binding site of this structural class (voltage-sensor domain 4,
transmembrane segments S2-S3) is distinct from the homologous
pore region in which the local anesthetics reside and most likely
confers the observed pharmacological selectivity.15
In addition to this pioneering work, other scientists have
designed compounds to exploit this novel binding site.
Genentech16 and Amgen17 have recently disclosed structurally
distinct aryl sulfonamides exemplified by compounds 1b and 1c,
respectively. In addition, potent and selective acyl sulfonamides
have been reported by Amgen (i.e. compound 2)18, Pfizer19 and
Merck,20 with competitive binding studies suggesting a similar
binding mode to the aryl sulfonamides.
Pharmacological treatments for chronic pain have historically
included opioids (i.e. morphine, oxycodone)5, non-steroidal anti-
inflammatory drugs (NSAIDs, i.e. naproxen, ibuprofen)6, anti-
convulsants (i.e. pregabalin, gabapentin)7 and serotonin-
norepinephrine reuptake inhibitors (SNRIs, i.e. duloxetine,
venlafaxine).8 While each of these modalities can be effective,
complete and sustained relief from pain syndromes is
unfortunately rare. Furthermore, utility is limited due to a
multitude of adverse side effects including addiction (opioids),
insomnia (SNRIs), sexual dysfunction (SNRIs) and
gastrointestinal issues (NSAIDs).
We were interested in developing a unique class of
conformationally-restricted, bicyclic aryl sulfonamides in hopes
of bringing structural novelty to the field with potential
improvements in pharmacokinetic and/or physicochemical
properties. Targeting scaffolds of generic structure 3, a series of
(6,5)- and (6,6)-frameworks were explored with an emphasis on
maximizing ligand efficiency (LE)21, lipophilic ligand efficiency
(LLE)22 and selectivity against Nav1.5 (Table 1). The in vitro
An alternative therapy for the treatment of chronic pain
involves the use of local anesthetics. In particular, lidocaine has
been widely leveraged for the rapid relief of pain in both
injectable and topical (Lidoderm®) formats.9 Its putative mode of
action involves the non-selective blockade of Nav1 voltage-gated
sodium channels (VGSCs), which are key regulators of electrical
signaling pathways. As such, VGSCs are responsible for the
rising phase of action potentials in excitatory cells such as
sensory neurons in response to changes in membrane potential.10
The nine reported VGSCs have varying tissue distribution
patterns and pharmacology.11 Nav1.1 and Nav1.2 are localized in
the central nervous system (CNS) whereas Nav1.3 is
embryonically expressed. Nav1.4 and 1.5 are largely localized in
skeletal muscle and cardiac myocytes, respectively. While
Nav1.6 is expressed in both the CNS and peripheral nervous
system (PNS), Nav1.7, 1.8 and 1.9 are primarily localized in the
PNS.
profiling of compounds leveraged
a
PatchXpress® (PX)
automated patch clamp system with a protocol tuned to assess
inhibition of channels in their inactivated states.23 From an initial
investigation of structure-activity relationships (SAR),
thiazolinone 3b, dihydro-benzoxazinone 3c and benzoxazolinone
3d were each inactive against Nav1.5 (IC50 > 30 µM). Among
these encouraging bicyclic scaffolds, benzoxazolinone 3d
emerged with the most promise due to its superior Nav1.7 activity
(IC50 = 486 nM), LE (0.33) and LLE (4.7).24,25
Table 1. Bicyclic aryl sulfonamide structure-activity relationshipsa
N
O
O
N
S
S
N
H
X
X
X
3a-d
Nav1.7 IC50 (nM) Nav1.5 sel
cLogP26
Cmpd
Bicycle
O
LE
LLE
3.0
Studies on human genetics suggest that the Nav1.7 isoform
may be a principle driver of pain signaling. In particular, loss-of-
function (LOF) mutations in Nav1.7 lead to channelopathy-
associated indifference to pain12 while gain-of-function (GOF)
mutations elicit debilitating pain syndromes such as
erythromelalgia.13 While inhibition of Nav1.7 may contribute to
the efficacy of local anesthetics, the CNS and cardiovascular side
effects associated with their systemic exposure may be attributed
to a lack of pharmacological selectivity with respect to the
Nav1.1/Nav1.2 and Nav1.5 channels, respectively.
O
S
N
H
3a
3026
6x
2.5
0.30
N
N
O
O
S
N
H
3b
970
>31x
2.5
0.30
3.5
N
O
S
O
O
S
S
N
H
3c
815
486
>37x
>62x
1.7
1.6
0.32
0.33
4.4
4.7
N
O
O
O
O
N
H
3d
N
O
O
aNav1.7 and Nav1.5 in vitro activity measured by PatchXpress®23 protocols;
Nav1.5 sel = selectivity against Nav1.5; LE = ligand efficiency; LLE =
lipophilic ligand efficiency.
The synthesis of benzoxazolinone 3d and related analogs (11-
13, 15-17) utilized the general sequence detailed in Scheme 1.24
Lithiation of amino-heterocycle 4 with sulfonyl chloride 5
provided intermediate 6. Mitsunobu coupling with an alcohol
building block mediated by diethyl azodicarboxylate (DEAD)
and triphenylphosphine gave the ultimate intermediate, which
subsequently underwent a global deprotection with trifluoroacetic
acid (TFA) to afford the described compounds.
Figure 1. Aryl sulfonamide Nav1.7 inhibitors from Pfizer (1a), Genentech
(1b) and Amgen (1c). Acyl sulfonamide Nav1.7 inhibitor from Amgen (2).
The significant therapeutic potential of pharmacologically-
selective, peripherally-restricted Nav1.7 blockers has attracted

Scheme 1. Synthetic strategy for benzoxazolinones 3d, 11-13, 15-17a
which positioned the phenyl ring into a more bioactive
orientation.
R
R
O
O
R
O
O
N
O
O
S
Het
Het
S
Het
S
N
HN
a
Cl
b, c
H
R'
+
Gratifyingly, these potency enhancements were found to be
the
N
O
HN
O
HN
O
O
additive.
Exemplar
13,
incorporating
both
O
O
MeO
OMe
MeO
OMe
R''
5
4
6
3d 11-13 15-17
, ,
tetrahydroisoquinoline and methyl groups, featured a Nav1.7 IC50
of 21 nM and a 1.6-unit increase in LLE relative to initial lead
compound 3d. Furthermore, its Nav1.5 selectivity exceeded
1,000-fold and was thus comparable with previously-reported
aryl sulfonamides (Figure 1).
aReagents and conditions: (a) LHMDS, THF, -78 °C to RT, 18 h, 23-79%; (b)
alcohol, DEAD, Ph3P, THF, 0 °C - RT, 3 h, 43-65%; (c) TFA, DCM, RT, 30
min, 48-90%.
The synthesis of compound 14 leveraged a complimentary
sequence featuring the sulfonamide formation as the penultimate
step (Scheme 2). This strategy facilitated the investigation of an
array of heteroaryl sulfonamides and greatly aided our
understanding of the underlying SAR.27 Here, palladium-
catalyzed cross coupling of 6-bromo-5-fluorobenzo[d]oxazol-
2(3H)-one (7) with benzyl mercaptan afforded versatile
intermediate 8. The preparation of compound 14 required a
Mitsunobu coupling with (S)-tert-butyl 8-(1-hydroxyethyl)-3,4-
dihydroisoquinoline-2(1H)-carboxylate to provide 9. Oxidation
with 1,3-dichloro-5,5-dimethylimidazolidine-2,4-dione gave
sulfonyl chloride 10, which was then subjected to standard
The in vitro activity of compound 13 was also assessed by
investigating the inhibition of tetrodotoxin (TTX)-sensitive Nav
current in freshly-harvested neurons of the dorsal root ganglion
(DRG).28 Nav potency measured for human in this format (IC50
=
31 nM) was consistent with that exhibited in the recombinant
Nav1.7 PatchXpress® protocol (PX IC50 = 21 nM). The activity of
compound 13 in mouse DRG’s (IC50 = 82 nM) was comparable
to that of human. This contrasted sharply with rat, however, as
the inhibition of TTX-sensitive sodium current in rat DRG’s
featured an IC50 of 2371 nM. This species-dependent in vitro
activity is consistent with previously-reported aryl sulfonamides
and may be due to specific amino acid differences in domain 4 of
the voltage-sensor region (VSD4).15
sulfonamide
formation
conditions
and acid-mediated
deprotection to afford 14.27
Scheme 2. Synthesis of benzoxazolinone 14a
In probing its ancillary profile, benzoxazolinone 13 was
inactive against CYP’s, PXR, hERG (IKr) and Cav1.2.
Unfortunately, it was non-selective against the Nav1.2 channel
(PX IC50 = 29 nM). However, the brain/plasma and CSF/plasma
ratios in rat were found to be 1% and 0%, respectively.
Considering that Nav1.2 is localized in the CNS, this peripheral
restriction helped mitigate our concerns with respect to the
observed Nav1.2 activity.
The pharmacokinetic properties of compound 13 in rat
featured an unbound clearance (CLu,p)29 of 360 mL/min/kg
(fraction unbound (fu) = 0.133 in rat) and a half-life (T1/2) of 0.8 h
following iv dosing (2 mpk). Disappointingly, the compound
exhibited poor oral bioavailability (F = 2% following 10 mpk po
dose), possibly due to a lack of cell permeability (Papp < 2 x 10-6
aReagents and conditions: (a) benzyl mercaptan, Pd2(dba)3, Xantphos,
DIPEA, THF, 120 °C, 2 h, 52%; (b) (S)-tert-butyl 8-(1-hydroxyethyl)-3,4-
dihydroiso-quinoline-2(1H)-carboxylate, DEAD, n-Bu3P, THF, 0 °C, 2 h,
43%; (c) 1,3-dichloro-5,5-dimethylimidazolidine-2,4-dione, AcOH, THF,
H2O, 0 °C, 5 min, 52%; (d) 4-chloro-N-(2,4-dimethoxybenzyl)pyridin-2-
amine, DCM, pyridine, RT, 12 h, then TFA, DCM, RT.
Figure 2. Combination of two potency-enhancers to give 13.
N
N
O
O
O
O
N
N
S
S
aryl substitution
S
S
N
N
H
H
N
H
2
N
O
N
O
O
O
3
3d
11
Nav1.7 IC50 = 486 nM
Nav1.5 sel > 62x
Nav1.7 IC50 = 190 nM
Nav1.5 sel > 158x
cLogP = 1.6, LLE = 4.7
cLogP = 1.1, LLE = 5.7
methylation
methylation
N
N
O
O
O
O
N
N
S
S
aryl substitution
S
S
N
N
H
N
Me
Me
H
H
N
O
N
O
cm/sec).
O
O
12
13
Figure 3. %Inhibition of formalin-induced nociceptive behavior compared to
vehicle-treated mice after subcutaneous (sc) administration (10/30/100 mpk,
90 min pre-treatment time to align with Tmax measured in pharmacokinetic
studies) of compound 13. Compound 13 significantly attenuated Phase 2
responses after the 30 and 100 mpk doses (ANOVA followed by Dunnett’s
multiple comparison test; * P< 0.05, ** P<0.01). Exposures were measured
for compound 13 at 3 h post-administration.
Nav1.7 IC50 = 74 nM
Nav1.5 sel = 287x
cLogP = 1.9, LLE = 5.2
Nav1.7 IC50 = 21 nM
Nav1.5 sel = 1381x
cLogP = 1.4, LLE = 6.3
Early lead optimization efforts involving the benzoxazolinone
structural class revealed two distinct potency-enhancers. For one,
incorporation of polar substituents at the 2- or 3-positions of the
phenyl group was generally found to increase Nav1.7 activity
while lowering cLogP. In a key example, tetrahydroisoquinoline
11 featured a potency increase exceeding two-fold relative to
parent compound 3d (Figure 2). With a cLogP of 1.1, its LLE
(5.7) also increased significantly. Importantly, this modification
did not increase activity with respect to Nav1.5 (IC50 > 30 µM).
An additional potency enhancement was found by incorporating
a methyl group at the benzyl carbon, providing (R)-eutomer 12.
This resulted in nearly a seven-fold improvement in Nav1.7
activity relative to 3d, potentially by providing a gearing effect
Utilizing subcutaneous (sc) administration, the in vivo activity
of compound 13 was assessed in a mouse formalin paw assay,
which has been frequently leveraged as a preclinical indicator of
antinociceptive behavior.30 In this experiment, formalin was
injected into the hind paw of a mouse, resulting in a number of
nociceptive behaviors including licking, biting and flinching. The
total time spent exhibiting nociceptive behaviors was recorded in

5 min intervals for a maximum of 60 min. The 0 – 5 min period
post formalin injection (Phase 1) is generally indicative of direct
activation of nociceptors while the 25 – 30 min period following
administration (Phase 2) is characteristic of a more complex
response involving inflammation, injured afferents and central
sensitization. Data was normalized and expressed as %inhibition
compared to the amount of nociceptive behavior observed in
vehicle-treated mice. A 100 mpk sc dose of compound 13
administered 90 min prior to the formalin injection significantly
attenuated this behavior for both time intervals (Figure 3). Full
efficacy was observed for Phase 2, and subsequent analysis of the
terminal exposure provided an IC50 of 23 µM. With a fraction
unbound (fu) of 0.065 in mice, the unbound efficacious drug
exposure (IC50,u) for 13 was 1.5 µM, which is approximately 50-
fold above its mouse PX IC50 (30 nM). This is consistent with
previously-reported aryl sulfonamide PK/PD relationships in
preclinical pain models.16,17
acidity (pKa = 5.3) than the thiadiazole sulfonamide of exemplar
13 (pKa = 3.5), thus reducing the relative zwitterionic character
(∆pKa) of the compound (Table 3). Gratifyingly, the oral
bioavailability of 16 in rat was 30% (10 mpk po dose),
constituting a significant improvement over benzoxazolinone 13.
Surprisingly, despite the reduction in PSA and zwitterionic
character, compound 16 featured a Papp of only 2.5 x 10-6 cm/sec.
With high permeability not required for oral bioavailability, this
suggested that active transport may have been a driving factor in
the observed oral exposure. Notably, compound 16 also featured
improvements in unbound clearance and half-life in comparison
to exemplar 13.
In an effort to more effectively balance Nav1.7 activity,
selectivity and desirable pharmacokinetic properties, the
structure-activity relationships of the N-benzoxazolinone
substituent were re-examined with the 6-fluoropyridyl
sulfonamide in place. This culminated in the discovery of
benzylamine 17 (Figure 4a), which featured four-fold
improvements in Nav1.7 activity (IC50 = 39 nM) and selectivity
against Nav1.5 (850x) in relation to compound 16. Furthermore,
benzoxazolinone 17 exhibited reduced unbound clearance (CLu,p
= 170 mL/min/kg; fu (rat) = 0.133), an extended half-life (T1/2 = 3
h) and 50% oral bioavailability in rat, which may be attributed to
a slight improvement in permeability (Papp = 4 x 10-6 cm/sec).
Importantly, following oral administration, 17 demonstrated
robust in vivo efficacy in the mouse formalin paw test with a
Phase 2 interval IC50 of 7.4 µM (Figure 4b,c). The corresponding
unbound drug level (IC50,u = 1.1 µM; fu (mouse) = 0.145) is 100-
In order to further progress the benzoxazolinone structural
class, the lack of oral bioavailability of compounds such as 13
needed to be addressed. One component of our strategy to
enhance oral exposure centered on reducing polar surface area
(PSA) through modification of the aryl sulfonamide moiety
(Table 2). In particular, replacing the thiadiazole with substituted
pyridines was most effective at modulating PSA while
maintaining acceptable physicochemical properties (i.e. cLogP <
4). While these modifications each proceeded with significant
erosion of Nav1.7 potency, a portion of this activity was
recovered through the installation of a potency-enhancing fluoro-
substituent on the benzoxazolinone scaffold (R = F, Scheme 1).
Ultimately, of the initial set of compounds investigated, 6-
fluoropyridyl sulfonamide 16 featured the most attractive balance
of Nav1.7 potency (150 nM), Nav1.5 selectivity (210x) and LLE
fold above the mouse PX potency (IC50 = 11 nM) and thereby
comparable to the in vitro/in vivo relationship of 13.
(4.2) while lowering PSA (106) relative to compound 13.
Figure 4. (a) Profile of compound 17. (b) %Inhibition (* P< 0.05, ** P<0.01)
of formalin-induced nociceptive behavior compared to vehicle-treated mice
after oral (po) administration (20/40/60 mpk, 60 min pre-treatment time) of
17. (c) Phase 2 exposure-response (IC50 = 7.4 µM) of 17.
Table 2. Adjusting PSA through modification of aryl sulfonamidea
aHet = heterocycle; Nav1.7 and Nav1.5 in vitro activity measured by
In summary, novel, conformationally-restricted aryl
sulfonamides have been discovered with high potency against
Nav1.7 and excellent pharmacological selectivity against Nav1.5.
Initial SAR investigations unearthed two distinct potency
enhancers which, when combined, led to compound 13 with
outstanding lipophilic ligand efficiency, exquisite selectivity
against Nav1.5, limited CNS penetration and dose-dependent in
vivo efficacy. Tractability with respect to improving oral
bioavailability was established with relatively minor structural
modification, leading to exemplar 17 (F = 50% in rat) which
exhibited comparable potency, selectivity and in vivo activity
relative to benzoxazolinone 13. Efforts to leverage these small
PatchXpress®23 protocols; Nav1.5 sel = selectivity against Nav1.5; PSA =
polar surface area; LLE = lipophilic ligand efficiency.
Table 3. Physicochemical and rat pharmacokinetic properties of 13 and 16a
a∆pKa = pKa difference between conjugate acid of tetrahydroisoquinoline
(8.9) and aryl sulfonamide; PSA = polar surface area; Papp = permeability
coefficient; CLu,p = unbound clearance; T1/2 = half-life.
Further inspection of the properties of benzoxazolinone 16
revealed that the 2-fluoropyridyl sulfonamide exhibited lower

molecules to further probe the viability of Nav1.7 as a pain target
for drug discovery remain in progress.
N.A.; Storer, R.I.; Stupple, P.A.; Castle, N.A.; Hounshell, J.A.; Rivara,
M.; Randall, A.; Dib-Hajj, S.D.; Krafte, D.; Waxman, S.G.; Patel, M.K.;
Butt, R.P.; Stevens, E.B. PLoS One 2016, 11, e0152405 and references
cited therein.
Acknowledgements
15. McCormack, K.; Santos, S.; Chapman, M. L.; Krafte, D. S.; Marron, B.
E.; West, C. W.; Krambis, M. J.; Antonio, B. M.; Zellmer, S. G.;
Printzenhoff, D.; Padilla, K. M.; Lin, Z.; Wagoner, P. K.; Swain, N. A.;
Stupple, P. A.; de Groot, M.; Butt, R. P.; Castle, N. A. Proc. Nat. Acad.
Sci. 2013, 110, E2724-E2732.
The authors would like to thank Dr. Charles Ross III and Mr.
Vincent Van Nostrand for HR-MS analysis and Mr. Andrew
Danzinger for in vivo data analysis.
A. Supplementary data
16. (a) Ahuja, S.; Mukund, S.; Deng, L.; Khakh, K.; Chang, E.; Ho, H.;
Shriver, S.; Young, C.; Lin, S.; Johnson, Jr., J.P.; Wu, P.; Li, J.; Coons,
M.; Tam, C.; Brillantes, B.; Sampang, H.; Mortara, K.; Bowman, K.K.;
Clark, K.R.; Estevez, A.; Xie, Z.; Verschoof, H.; Grimwood, M.;
Dehnhardt, C.; Andrez, J.-C.; Focken, T.; Sutherlin, D.P.; Safina, B.S.;
Starovasnik, M.A.; Ortwine, D.F.; Franke, Y.; Cohen, C.J.; Hackos,
D.H.; Koth, C.M.; Payandeh, J. S. Science 2015, 350, 1491-1500. (b)
Focken, T.; Liu, S.; Chahal, N.; Dauphinais, M.; Grimwood, M.E.;
Chowdhury, S.; Hemeon, I.; Bichler, P.; Bogucki, D.; Waldbrook, M.;
Bankar, G.; Sojo, L.E.; Young, C.; Lin, S.; Shuart, N.; Kwan, R.; Pang,
J.; Chang, J.H.; Safina, B.S.; Sutherlin, D.P.; Johnson, Jr., J.P.;
Dehnhardt, C.M.; Mansour, T.S.; Oballa, R.M.; Cohen, C.J.; Robinette,
C.L. ACS Med. Chem. Lett. 2016, 7, 277-282; (c) Sun, S.; Jia, Q.;
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M. E.; Chowdhury, S.; Young, C.; Cohen, C. J.; Oballa, R. Bioorg.
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Supplementary data associated with this article can be found
in the online version, at http://xxx
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29. Unbound clearance (CLu,p) is defined as: CLu,p = CL/fu, where CL =
total plasma clearance (mL/min/kg) and fu = fraction unbound.
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