Structure-based design, synthesis and biological evaluation of a novel series of isoquinolone and pyrazolo[4,3-c]pyridine inhibitors of fascin 1 as potential anti-metastatic agents

Article abstract of DOI:10.1016/j.bmcl.2019.01.035

Fascin is an actin binding and bundling protein that is not expressed in normal epithelial tissues but overexpressed in a variety of invasive epithelial tumors. It has a critical role in cancer cell metastasis by promoting cell migration and invasion. Here we report the crystal structures of fascin in complex with a series of novel and potent inhibitors. Structure-based elaboration of these compounds enabled the development of a series with nanomolar affinities for fascin, good physicochemical properties and the ability to inhibit fascin-mediated bundling of filamentous actin. These compounds provide promising starting points for fascin-targeted anti-metastatic therapies.

Full text of DOI:10.1016/j.bmcl.2019.01.035

Accepted Manuscript
Structure-based design, synthesis and biological evaluation of a novel series of
isoquinolone and pyrazolo[4,3-c]pyridine inhibitors of fascin 1 as potential anti-
metastatic agents
Stuart Francis, Daniel Croft, Alexander W. Schüttelkopf, Charles Parry, Angelo
Pugliese, Ken Cameron, Sophie Claydon, Martin Drysdale, Claire Gardner,
Andrea Gohlke, Gillian Goodwin, Christopher H. Gray, Jennifer, Konczal,
Laura McDonald, Mokdad Mezna, Andrew Pannifer, Nikki Paul, Laura
Machesky, Heather McKinnon, Justin Bower
PII:
S0960-894X(19)30056-3
https://doi.org/10.1016/j.bmcl.2019.01.035
BMCL 26272
DOI:
Reference:
Bioorganic & Medicinal Chemistry Letters
To appear in:
Received Date:
Revised Date:
Accepted Date:
26 November 2018
24 January 2019
29 January 2019
Please cite this article as: Francis, S., Croft, D., Schüttelkopf, A.W., Parry, C., Pugliese, A., Cameron, K., Claydon,
S., Drysdale, M., Gardner, C., Gohlke, A., Goodwin, G., Gray, C.H., Jennifer, Konczal, McDonald, L., Mezna, M.,
Pannifer, A., Paul, N., Machesky, L., McKinnon, H., Bower, J., Structure-based design, synthesis and biological
evaluation of a novel series of isoquinolone and pyrazolo[4,3-c]pyridine inhibitors of fascin 1 as potential anti-
metastatic agents, Bioorganic & Medicinal Chemistry Letters (2019), doi: https://doi.org/10.1016/j.bmcl.
2019.01.035
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Structure-based design, synthesis and biological evaluation
of a novel series of isoquinolone and pyrazolo[4,3-c]pyridine
inhibitors of fascin 1 as potential anti-metastatic agents
Stuart Francisa, *, Daniel Crofta, Alexander W. Schüttelkopfa, Charles Parrya,
Angelo Pugliesea, Ken Camerona, Sophie Claydona, Martin Drysdalea, 1, Claire
Gardnera, Andrea Gohlkea, Gillian Goodwina, Christopher H. Graya, Jennifera
Konczala, Laura McDonalda, Mokdad Meznaa, Andrew Pannifera, 2, Nikki Paulb,
Laura Macheskyb, c, Heather McKinnona and Justin Bowera
a Drug Discovery Unit, CRUK Beatson Institute, Glasgow G61 1BD (UK)
b Cell Migration Laboratory, CRUK Beatson Institute, Glasgow G61 1BD (UK)
c Institute of Cancer Sciences, University of Glasgow, G61 1QH, Glasgow, UK
*Corresponding author at: Drug Discovery Unit, CRUK Beatson Institute,
Glasgow G61 1BD (UK). E-mail address: s.francis@beatson.gla.ac.uk
1 Current address: Broad Institute, Cambridge, MA 02142, US
2 Current address: Medicines Discovery Catapult, Mereside, Alderly Park,
Alderley Edge SK10 4TG, UK
Keywords: virtual screening, fragments, drug discovery, medicinal chemistry,
cancer

Abstract
Fascin is an actin binding and bundling protein that is not expressed in normal
epithelial tissues but overexpressed in a variety of invasive epithelial tumors.
It has a critical role in cancer cell metastasis by promoting cell migration and
invasion. Here we report the crystal structures of fascin in complex with a
series of novel and potent inhibitors. Subsequent structure-based elaboration
of this and related compounds enabled the development of a series with
nanomolar affinities for fascin, good physicochemical properties and the ability
to inhibit fascin-mediated bundling of filamentous actin. These compounds
provide promising starting points for fascin-targeted anti-metastatic therapies.
Fascin 1 (hereafter termed fascin) is an evolutionarily conserved actin binding
protein that cross-links filamentous actin (F-actin) into tightly packed parallel
bundles driving the formation of various cell surface protrusions, such as
filopodia and invadopodia, that promote cell migration and invasion.1 It’s
expression is highly restricted in adult human tissues.2 Fascin is either absent
or shows low expression in normal epithelial tissues but is overexpressed in a
number of cancers, with expression levels correlating with overall cancer
aggressiveness and predicting poor clinical outcome.3, 4 Conversely, genetic
knockdown of fascin decreases tumor cell invasion both in vitro and in vivo,5, 6
suggesting that fascin may be a viable target for anticancer/antimetastatic
drugs. Huang et al. have disclosed compounds which bind to fascin and
inhibit actin bundling.7-9 However, in our hands a number of these compounds
bound with modest (10–100 µM) affinity and suffered from poor solubility.
2

In order to identify novel fascin compounds, with favourable properties, we
undertook a surface plasmon resonance (SPR) screen using our collection of
1050 fragments and identified 53 hits (hit rate 5%). Follow-up protein
crystallography yielded a range of fragments binding to multiple sites on the
protein.
Figure 1. Fascin structure and fragment 1 binding. A) Chemical structure of
compound 1. B) Overall structure of fascin represented as a cartoon with the
four β-trefoil domains colored differently and labelled. The bound compound 1
is shown as cyan spheres (PDB id 6I0Z). C) The interface between domains 1
and 2 in apo-fascin (PDB id 3P53)10. Domains are delineated by separate
surfaces colored as in B) and labelled. Residues at the interface are shown as
grey sticks and labelled with single-letter amino acid codes and residue
numbers. D) Compound 1 bound to fascin, representation and view as in C)
with the compound shown as cyan sticks. The structures were superimposed
on domain 1 only. E) Detailed view of the binding site shown as a semi-
transparent surface with surrounding protein residues drawn as sticks colored
and labelled. Hydrogen bonds are shown as dashed pale green lines, other
conventions as for D).
3

The N-phenylacetamide 1 (Figure 1A) binds efficiently (SPR Kd = 92 μM;
ligand efficiency 0.43)11 in a buried pocket between the first and second β-
trefoil domain (Figure 1B) and was therefore selected for further development.
4

Binding of compound 1 induces a hydrophobic pocket in domain 1, mainly by
displacing Trp101. In addition, domain 1 pivots by ≈15°, reorienting residues
on either side of the domain interface and creating a narrow channel to the
protein surface (Figures 1C and 1D). The dichlorophenyl moiety of 1 fills the
hydrophobic pocket, while the acetamide engages in hydrophilic interactions
with domain 2, with its carbonyl accepting a hydrogen bond from the
backbone of Leu214 (Figure 1E). While the completely enclosed binding site
makes compound 1 a highly efficient ligand, it hampered attempts to develop
this series.
Figure 2. Fascin undergoes a significant conformational change upon binding
of compounds 2 and 3. A) Chemical structures of 2 and 3. B) Apo-fascin
(PDB id 3P53, red) and the fascin·2 complex (PDB id 6I10, purple)
superimposed on the relatively rigid domains 2–4 (grey; RMSD = 1.1 Å for
348 Cα atoms), viewed along the domain 1 rotation axis. C) Compound 2
bound to fascin oriented as Figures 1C/D (proteins superimposed on domain
1). D) Detail view of the fascin·2 complex. Conventions as in Figure 1E, the
red sphere represents a bound water molecule. E) Detailed view of the
fascin·3 complex (PDB id 6I11).
5

The importance of this fragment binding site was highlighted when we
determined the crystal structure of compound 2 (Figure 2A) previously
identified by Huang et al. to inhibit fascin-mediated actin bundling.12 To
6

accommodate the larger compound 2, domain 1 undergoes a more dramatic
conformational change, rotating 35° around an axis almost parallel to a line
connecting the first two β-trefoil domains (Figure 2B). For the compound
binding site (Figure 2C) this almost pure rotation results in a 6 Å ‘drop’ of
domain 2 relative to domain 1, so that the Phe216 side chain, which in the
fascin·compound 1 complex lines the channel, now extends the hydrophobic
pocket (cf. Figures 1D and 2C) where the compound’s dichlorobenzyl moiety
binds. More importantly, the conformational change opens up the channel so
that it can accommodate the rest of the compound. The pyrazolopyrimidinone
core rests on a relatively flat surface created by the salt-bridged side chains of
Glu215 and Arg217. Additionally, compound 2 accepts a hydrogen bond from
Phe216 and makes a relatively weak water-bridged interaction with the side
chain of Glu215 (Figure 2D). The induced conformational changes provide 2
with access to the protein surface creating opportunities for structure-driven
compound elaboration. Notably, the recently disclosed structure of fascin in
complex with an unrelated small molecule bound in the same site9 shows
fascin adopting a similar conformation (RMSD < 1.3 Å for 483 Cα atoms).
To identify compounds which could potentially fill these additional areas a
hybrid virtual screen was carried out. The first method was structure-based:
809 commercial analogues of compound 2 and ≈2.7 million lead-like
molecules from our in-house virtual library were docked13 in the enclosed site.
To prioritize the docked compounds, a multi-parameter optimization was
performed using Pareto efficiency14 as the ranking technique with calculated
free energy of binding (from docking), QED15 and interaction pattern similarity
7

(based on compound 2 interaction fingerprints)16 as the parameters to
optimize. The second method was ligand-based using shape-similarity17 to
find analogues of compound 2 in our in-house library. Combining the results,
110 commercial compounds were tested by SPR at a screening concentration
of 100 µM. The resulting binders were validated by co-crystallization and SPR
dose-response experiments. Eighteen compounds were confirmed to bind in
the same site as 2, and three yielded Kd values <100 μM. Of these three, we
decided to progress the isoquinolinone 3 (SPR Kd = 29.3 ± 5.8 µM; Figures
2A and 2E), which maintains affinity similar to 2 despite substituent
truncations from both the benzyl and the core ring system. The pyrazolamide
moiety forms an edge-to-face aromatic interaction with the Trp101 side chain.
It also moves the bridging water seen in the fascin·compound 2 complex
structure deeper into the binding site. This water now hydrogen-bonds to the
Thr213 side chain, the Leu214 backbone carbonyl and the ligand amide in
addition to the Glu215 side chain, which ‘follows’ it by adopting a different
rotamer (Figures 2D and 2E). Analysis of this water with MOE 3D-RISM18
suggests it is relatively tightly bound (ΔG = -3.9 kJ/mol) and that displacing it
would likely be energetically unfavorable.
In order to measure the effect of these compounds on fascin activity we
developed a robust and highly reproducible in vitro F-actin bundling assay,
based on a previously published method.19 Unlike compound 1, both 2 and 3
inhibit fascin in this bundling assay. Compound 3 inhibits actin bundling with
an IC50 of 67.9 ± 3.5μM, giving an approximately two-fold fall-off from SPR
binding affinity. A similar fall-off is seen for other compounds in this series.
8

Considering that both 1 and 2 place a substituted phenyl into the hydrophobic
pocket, it seemed plausible that the plain benzyl of 3 is not optimal for filling
the available space. Additionally, given that this induced pocket is likely to
show some plasticity, it may be possible to open it up further by extending the
compound. To investigate this, we synthesized a series of benzyl derivatives
of 3 (Table 1). Introduction of a para-halo substituent (compounds 4 and 5)
increased binding affinity ≈14-fold compared to 3. The crystal structure of 5
bound to fascin shows a binding mode without substantial changes in either
ligand or protein conformation compared to the fascin·3 complex (Figure
S1A). A single meta-fluoro substituent (6) is equipotent while m-chloro
substitution (7) improved affinity, though less so than 4 or 5. This may be
partly explained by the slight differences in binding mode for meta substituted
compounds compared to 3, in which the benzyl moiety is rotated to line up the
m-substituent with a pocket indentation (Figure S1B). In light of this
conformational divergence, it is not surprising that m,p-dihalo compounds
exhibit sub-additive affinity gains, though both 8 and 9 showed improved
binding over mono- or unsubstituted analogues with SPR Kd values of 1.2 and
1.5 μM respectively. The structure of the fascin·9 complex shows the
compound adopts a conformation with the phenyl rotated to an intermediate
position compared to the meta and para analogues (Figure S1C). Larger meta
or para substituents (e.g. 10 and 11; Figure S1D) are tolerated by expanding
the hydrophobic pocket. However, the associated conformational penalty
consistently makes these compounds less potent. Introduction of an ortho
substituent decreases potency both in combination with a para substituent
9

(12) or as a single substituent (data not shown). Taken together the SAR
suggests that m,p-dichloro substitution (9) is close to optimal in this series.
Table 1. Variation of benzyl substituents
Kd ± SDa (µM)
Compound
IC50 ± SDb (µM)
3
4
5
6
7
8
29.3 ± 5.8
2.7 ± 0.1
2.7 ± 0.1
29.2 ± 0.9
7.6 ± 2.5
1.2 ± 0.1
1.5 ± 0.1
6.6 ± 2.0
46 ± 1.7
67.9 ± 3.5
nd
4.6 ± 0.3
nd
11.4 ± 4.2
2.1 ± 0.8
1.3 ± 0.2
8.6 ± 4.2
nd
9
10
12
a Kd: SPR binding affinity, values are mean ± standard deviation from n=2-10 separate experiments; b IC50:
compound concentration that reduces actin bundling by 50%, values are mean ± standard deviation
We next investigated altering the bicyclic scaffold of 3 (Table 2), taking care to
retain the pyridinone moiety, which we found to be essential for binding.
Complete deletion of the outer ring (13) led to a significant loss of affinity,
which can be partly recovered with the addition of a 3-amino substituent (14),
10

which donates an additional hydrogen bond to the Phe216 backbone
carbonyl. The naphthyridinones 16 and 17 maintain binding affinities similar to
the parent isoquinolinone, while placement of the naphthyridinone nitrogen
next to the amide (15) results in the formation of an intramolecular hydrogen
bond stabilising a conformation that is not optimal for fascin binding (Figure
S2A), and thus a decrease in binding affinity. For comparison, a matched
pyrazolopyridinone 19 shows 7-fold weaker binding.
11

Table 2. Variation of the bicyclic scaffold
Kd ± SDa (µM)
Compound
IC50 ± SDb
(µM)
X
Y
9
1.5 ± 1
1.3 ± 0.2
13
>100
nd
14
15
Y
X
21 ± 4.2
>100
nd
>100
16
17
18
19
X
X
X
X
1.6 ± 0.1
1.3 ± 0.1
>100
5.3 ± 0.8
3.8 ± 0.3
nd
10.0 ± 1.4
10.4 ± 0.2
X, R=Me; Y, R=3-pyrolidine;
a Kd: SPR binding affinity, values are mean ± standard
deviation from n=2-10 separate experiments; b IC50:
compound concentration that reduces actin bundling by
50%, values are mean ± standard deviation from n=2-4
separate experiments; nd: not determined.
12

Considering their improved physicochemical properties and chemical
tractability, we decided to progress a naphthyridinone, initially by adding
substituents to replicate the space filling of the cyclic sulphone of 2. A binding
mode comparison (Figure S2B) suggested that substitution from C5 would
provide the best-matched vector, though 6-substituents should be able to
access the same space. Due to concerns about the potential clash between a
5-substituent and the pyrazoloamide preventing the compound from adopting
the preferred fascin-binding conformation, we opted to elaborate 17 through
substitution from the 6-chloro derivative (Table 3). The introduction of simple
Table 3. 6-substitution of the napthyridinone core
Kd ± SDa (µM)
Compound
IC50 ± SDb (µM)
H
17
20
21
22
23
24
1.3 ± 0.1
1.1 ± 0.2
3.8 ± 0.3
nd
2.0 ± 0.1
nd
1.03 ± 0.03
0.58 ± 0.02
0.25 ± 0.1
nd
0.63 ± 0.09
0.51 ± 0.07
a Kd: SPR binding affinity, values are mean ± standard
deviation from n=2-10 separate experiments; b IC50:
compound concentration that reduces actin bundling by
50%, values are mean ± standard deviation from n=2-4
separate experiments; nd: not determined.
13

alkylamine substituents (20, 22) had no significant effect on fascin binding.
The sulphonamide (21) aiming to more closely replicate the sulphone of
compound 2 also failed to improve affinity. The piperazine 23 gave slightly
improved fascin binding, despite ostensibly placing a partial positive charge
close to the guanidine group of Arg217 (cf. Figure 2E). The piperidine
analogue (24) shows further improved fascin binding and inhibition. The
crystal structure of the fascin·compound 24 complex shows the compound
binding broadly as expected (Figures S3A and S3B). The naphthyridinone
makes an additional water-bridged interaction with the Phe216 backbone
carbonyl. The piperidine orients to fill the space between Ala58 and Arg217
(Figure S3C), but does not make any specific interactions, as its amine points
towards bulk solvent. Comparing the binding modes of 24 and 9 reveals that
the core ring system of 24 is rotated slightly (Figure S3D), possibly to optimize
the fit of the piperidine. This small rotation has an amplified effect on the
position of the pyrazoloamide, bringing the pyrazole closer to Trp101 and
Arg225 while at the same time improving the hydrogen bond from the amide
to the bridging water. The displacement observed for 24 suggests that
naphthyridinones with bulky 6-substituents may be sterically restricted from
adopting an optimal core binding mode. In light of this we chose to revisit the
pyrazolo series, where we had previously observed that the equally bulky
cyclic sulphone substituent of 2 was compatible with the ‘standard’ core
orientation (Figure S2B). The truncated compound 25 showed diminished
binding (Table 4), revealing that addition of either the pyrazoloamide in the 7-
position (to obtain 19) or the cyclic sulphone at N1 (to obtain 2) to this
compound improves fascin affinity more than 50-fold and 23-fold, respectively.
14

Combining these key features into one compound gave 26, with an SPR Kd of
0.6 μM, suggesting near-additive gains in binding affinity compared to 24 and
almost closing the potency gap to our best naphthyridinones.
We next investigated changes to the heteroaromatic amide. In line with the
predicted importance of the bridging water discussed above, any changes to
the amide (N-alkylation, carbonyl deletion) abolish fascin binding (not shown).
On the other hand, the methylpyrazole interacts with the protein through
stacking with the indole of Trp101. A number of compounds with alternative
heterocycles were made to probe this interaction, focusing on five- and six-
membered nitrogen-containing heterocycles. Of these the pyridin-4-yl 27
yielded the largest, albeit still modest, improvement over 26 in terms of both
affinity and inhibition. QM calculations (Figure S4) suggest that at least for
(hetero)aryl derivatives improved stacking with Trp101 may be a major factor
in this increase in potency.
Table 4. Further substitutions of the pyrazolopyridinone scaffold
Kd ± SDa (µM)
Compound
R1-group
R2-group
IC50 ± SDb (µM)
25
2
N
N
H
>500
nd
29.5 ± 8.3
0.60 ± 0.05
67.6 ± 2.4
0.63 ± 0.15
26
15

27
28
0.27 ± 0.04
0.09 ± 0.02
0.33 ± 0.06
0.24 ± 0.01
a Kd: SPR binding affinity, values are mean ± standard
deviation from n=2-10 separate experiments; b IC50:
compound concentration that reduces actin bundling by
50%, values are mean ± standard deviation from n=2-4
separate experiments; nd: not determined.
Given the success of 24 and to alleviate concerns about chemical stability of
the cyclic sulphone substituent, we opted to replace it with a 1-piperidin-4-yl.
Scheme 1. Reagents and conditions: (a) N, N-dimethylformamide dimethyl
acetal, ethanol r.t, (75%); (b) 4 tert-butyl 4-hydrazinopiperidine-1-carboxylate,
ethanol, reflux., (27%); (c-e) Bredereck’s, toluene reflux; 3,4-
dichlorophenyl)methanamine, acetic acid, toluene; sodium ethoxide, ethanol
16

(3 steps 85%) (f) Sodium hydroxide, ethanol r.t. (84%), (g) HATU, N,N-
diisopropylethylamine, DMF, r.t., (83%), (h) TFA, DCM r.t. (52%).
Synthesis of this was achieved starting from the commercially available
diethyl beta-ketoglutarate (29) and reacting with N,N-dimethylformamide
dimethyl acetal (Scheme 1).20 Addition of tert-butyl 4-hydrazinopiperidine-1-
carboxylate led to the pyrazole (31), which was further functionalised by
refluxing with Bredereck’s reagent followed by the addition of
dichlorobenzylamine. Partial cyclisation was observed at this stage, however,
the crude product was fully cyclised with sodium ethoxide. This gave
intermediate pyrazlopyridinone (32) in good yield over the three steps.
Saponifaction of the ester, coupling of the 4-amino pyridyl and removal of the
Boc protecting group furnished BDP-13176 (28). BDP-13176 further improved
fascin affinity, giving us the best fascin binder (SPR Kd = 85 ± 0.02 nM, LE =
0.29, ITC Kd = 50 nM; Figures 3A and 3B) and actin bundling inhibitor (IC50 =
240 ± 0.01 nM; Figures 3C and 3D).
Figure 3. Comparison of SPR binding affinity, ITC binding parameters and
functional bundling assay potency for BDP-13176. A) Multi-cycle kinetic curve
for BDP-13176 binding to immobilised (His8)2-fascin. Data were fitted using a
1:1 kinetic binding model. B) ITC titration thermogram and referenced
isotherm (first point removed) of BDP-13176 (150 µM in syringe) binding to
fascin (15 µM in cell). Fitting of the isotherm to a 1:1 binding model resulted in
the following binding parameters: N = 1.05 ± 0.01, Kd = (45 ± 7) nM, ΔH = (-
2400 ± 200) cal mol-1, ΔS = -45.9 cal mol-1 K-1. C) Inhibition of fascin bundling
17

activity by BDP-13176. Inhibition of bundling activity can be seen as fascin
and F-actin move from the pellet (P) to the supernatant (S) with increasing
concentrations of BDP-13176. D) Concentration-response curve for bundling
assay data shown in C).
The crystal structure of fascin in complex with BDP-13176 shows the
compound adopting the expected overall binding mode (Figure 4), but with a
slight core rotation in the opposite direction from that observed for 24 (Figure
S5). The compound`s in vitro physicochemical and DMPK properties (Table
18

S1) are within acceptable limits with low lipophilicity (LogD7.4=1.8) and
reasonable kinetic solubility (midpoint = 65µM). The compound was also
moderately stable in both human and mouse liver microsomes (Human Clint-
=6.4, Mouse Clint=11.8, µL/min/mg protein). However, the compound has low
Caco-2 permeability (A-B Papp=0.15x10-6 cm/s) and high efflux (efflux
ratio=37.8).
Figure 4. Binding of BDP-13176 to fascin. A) Crystal structure of the
fascin·BDP-13176 complex (PDB id 6I18). The bridging water seen in earlier
complexes is replaced by two ordered waters that together make the same
contacts as the single bound water. B) Interaction plot for BDP-13176 bound
to fascin.
19

A
L103
A95
A58
I93
L62
V60
L16
L48
W101
F14
R217
V134
F216
E215
T213
L214
B
In conclusion, fragment screening coupled with crystallography and
computational approaches allowed identification of a cryptic pocket within
fascin. Using compound 2 (Kd = 29.5 ± 8.3 µM)12 as a starting point combined
with virtual screening and structure-based design allowed us to develop
potent and functionally active fascin binders. Crystal structures reveal the
20

compounds bind with a hydrophobic ‘hook’ in an induced pocket between the
first two β-trefoil domains of fascin and from there extend towards the protein
surface, effecting a substantial conformational change in domain 1. While the
mechanism by which our compounds inhibit bundling remains unclear, it is
worth noting that fascin’s two major proposed actin binding regions involve
domain 1 and cross a domain boundary. The ligand-induced conformational
change would deform both these regions and thereby disrupt actin binding
(Figure S6). We anticipate these compounds to be a useful foundation to
further probe fascin’s potential role in tumor invasion and metastasis.
Acknowledgements
This research was supported by funding from CRUK (grants A17196 and
A17096) and the Pancreatic Cancer Research Fund. We would like to thank
Diamond Light Source for beamtime (proposals mx6683, mx8659 and
mx11651) and the staff of beamlines i02, i03 and i04 for their assistance. We
also thank David Sumpton and Gillian McKay for mass spectrometric
analyses, and Daniel James for informatics support.
Experimental Section
Experimental details can be found within the supplementary data file provided.
21

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Structure-based design, synthesis and biological evaluation
of a novel series of isoquinolone and pyrazolo[4,3-c]pyridine
inhibitors of fascin 1 as potential anti-metastatic agents
24