Structure-based design leads to potent and orally bioavailable inverse

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Structure-based design leads to potent and orally bioavailable inverse agonists of ROR#t Frank Narjes, Yafeng Xue, Stefan von Berg, Jesper Malmberg, Antonio Llinas, Roine I. Olsson, Johan Jirholt, Hanna Grindebacke, Agnes Leffler, Nafizal Hossain, Matti Lepistö, Linda Thunberg, Hanna Leek, Anna Aagaard, Jane McPheat, Eva L. Hansson, Elisabeth Back, Stefan Tångefjord, Rongfeng Chen, Yao Xiong, Ge hongbin, and Thomas Hansson J. Med. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.jmedchem.8b00783 • Publication Date (Web): 10 Aug 2018 Downloaded from http://pubs.acs.org on August 10, 2018

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Journal of Medicinal Chemistry

Structure-based design leads to potent and orally bioavailable inverse agonists of RORγt Frank Narjes,*† Yafeng Xue,§ Stefan von Berg,† Jesper Malmberg,† Antonio Llinas,‡ Roine I. Olsson,† Johan Jirholt,ǂ Hanna Grindebacke,ǂ Agnes Leffler,ǂ Nafizal Hossain,† Matti Lepistö,† Linda Thunberg,≠ Hanna Leek,≠ Anna Aagaard,§ Jane McPheat,¶ Eva L. Hansson,¶ Elisabeth Bäck,¶ Stefan Tångefjord,§ Rongfeng Chen,^ Yao Xiong,^ Ge Hongbin,^ Thomas G. Hansson† †

Medicinal Chemistry, ‡DMPK and ǂBioscience, Respiratory, Inflammation and Autoimmunity,

IMED Biotech Unit, AstraZeneca, Gothenburg, SE-43183 Mölndal, Sweden. §

Structure, Biophysics &FBLG and ¶Mechanistic Biology and Profiling, Discovery Sciences,

IMED Biotech Unit, AstraZeneca, Gothenburg, SE-43183 Mölndal, Sweden. ≠

Early Product Development, Pharmaceutical Sciences, IMED Biotech Unit, AstraZeneca,

Gothenburg, SE-43183 Mölndal, Sweden. ^

Pharmaron Beijing Co., Ltd., Taihe Road BDA, Beijing, 100176, P.R. China

E-mail: [email protected]

ACS Paragon Plus Environment

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ABSTRACT: Retinoic acid receptor-related orphan receptor γt (RORγt), has been identified as the master regulator of TH17 cell function and development, making it an attractive target for the treatment of autoimmune diseases by a small molecule approach. Herein we describe our investigations on a series of 4-aryl-thienyl acetamides, which were guided by insights from Xray co-crystal structures. Efforts in targeting the co-factor recruitment site from the 4-aryl group on the thiophene led to a series of potent binders, with nanomolar activity in a primary human TH17 cell assay. The observation of a molecule of DMSO binding in a sub-pocket outside the LBD inspired the introduction of an acetamide into the benzylic position of these compounds. Hereby, a hydrogen bond interaction of the introduced acetamide oxygen with the backbone amide of Glu379 was established. This greatly enhanced the cellular activity of previously weakly cell active compounds. The best compounds combined potent inhibition of IL-17 release with favorable PK in rodents with compound 32 representing a promising starting point for future investigations.

Introduction The nuclear receptor retinoic acid receptor-related orphan receptor gamma(RORγ, NR1F3, RORc) exists in two isoforms, with one isoform (RORγ, RORc1) widely expressed in a variety of tissues, and the expression of the second isoform (RORγt, RORc2) restricted to the thymus and cells of the immune system.1 RORγt is the key transcription factor for function and development of CD4+ T-helper 17 (TH17) cells and related IL-17 producing immune cells such as innate lymphoid 3 cells and γδ T cells.1-5 TH17 cells are characterized by the production of the cytokines IL-17A, IL-17F and IL-22 and play a key role in host defence against extracellular pathogens.6-7 Dysregulation of the TH17 pathway has been implicated in the pathology of a


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variety of autoimmune disorders such as psoriasis, Crohn’s disease, multiple sclerosis and rheumatoid arthritis.7-12 Antibodies targeting IL-17, its receptor IL-17RA, or the cytokines involved in the inflammatory pathway such as IL-23, have shown clinical efficacy in psoriasis and related autoimmune disorders.13-16 Nuclear receptors are ligand-inducible transcription factors, whose function can be modulated by binding of small molecules to the ligand-binding domain (LBD) of the receptor, thereby inducing conformational changes to the co-factor recruitment binding site, ultimately affecting gene transcription.17-19 RORγt has been shown to be active in the absence of ligands, but sterol derivatives were described to affect receptor function, and to control TH17 differentiation.20-23. The crystal structures of two sterol derivatives, agonist 25-hydroxychesterol and inverse agonist digoxin, provided insights into the molecular mechanisms leading to the different functional effects.24-25 Efforts to discover orally bioavailable inverse agonists of RORγt, as an alternative to antibody treatment, has generated a variety of different structural classes.26-29 Compounds affecting the receptor by binding to the LBD are not expected to exhibit isoform selectivity, since the two isoforms of RORγ differ only at their N-terminus, and share the same DNA and ligand binding domains.30-40 Recent clinical candidates from these efforts include GNE-3500,41 GSK805,42-43 GSK298127830 and VTP-4374244 (Figure 1). GSK2981278, whose structure has not been disclosed, was developed for the topical treatment of psoriasis, but failed to show efficacy in a phase 1 study,45 whereas Vitae Pharmaceuticals recently reported positive results for VTP-43742 from a Phase 2a study for the same indication. Oral administration of over four weeks was found to be safe and efficacious, resulting in a 24% reduction in Psoriasis Area Severity Index.46


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GNE-3500

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VTP-43742

GSK805

Figure 1. Selection of published inverse agonists of RORγt. We have recently disclosed a series of benzoxazepine based modulators, which we eventually abandoned due to metabolic instability of the compounds.39 The hit identification approaches we conducted to find new starting points included X-ray based fragment screening47 and the characterization of compounds from the literature. Among these were derivatives 1 and 2, previously described by scientists from GSK.48-49

Table 1. Profile of compounds 1-3. Cl O Cl

S X

O

SO2Et

Cl

S

N H

N H

1 (X = N) 2 (X = CH)

3

IC50 SPAa

IC50 FRETb

IC50 IL-17 Cellc

[µM]

[µM] (% eff.)

[µM] (% eff.)

1

0.009

0.022 (-87)

2

0.002

3

0.11

Cmpd

a

SO2Et

O

logDd

clogP

LLEe

0.18 (-75)

>4.2

5.5

2.6

0.023 (-82)

0.006 (-85)

4.5

6.0

2.6

0.18 (-96)

>3

>4.1

4.0

3.0

Displacement of tritiated ligand from human RORγt LBD (geometric mean n ≥ 2). bInhibition or activation of the

recruitment of SRC1-derived coactivator peptide (NCOA1 aa 677-700) to human RORγt LBD (geometric mean n ≥ 2); negative % efficacy (% eff.) values denote inverse agonism. cInhibition of IL-17 production from human primary TH17 cells (geometric mean of n ≥ 3); negative values of % efficacy signify inhibition of IL-17 production.


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d

Distribution coefficient between 1-octanol and aqueous phosphate buffer at pH 7.4. eLigand lipophilic efficiency

defined as SPA pIC50 – clogP.

Both compounds were potent binders in a radioligand binding assay (SPA) and behaved as inverse agonists in a FRET assay, showing functional suppression of the recruitment of a coactivator peptide derived from steroid receptor coactivator 1 (SRC1) to the RORγt LBD. The activity of 2 observed in the FRET assay was about 10-fold lower compared to the binding assay, which we ascribed to the conditions of the FRET assay, placing a limit on the lowest IC50 that can be determined at around 0.02 µM. They efficiently suppressed IL-17A production from primary human TH17 cells, with thiophene 2 being 30-fold more potent. Compound 2 is highly lipophilic, and pharmacokinetic properties in mouse were characterized by high plasma clearance and low oral bioavailability.49 Compound 3 was prepared as part of an early effort to understand the SAR and reduce lipophilicity. It was about 60-fold less active in the SPA assay, but we were intrigued by the observation, that despite the lack of the benzoate moiety, 3 behaved as an inverse agonist in the FRET assay. Even though 3 exhibited sub-micromolar binding potency, and efficacy in the FRET assay, it was not able to suppress IL-17 release from primary human TH17 cells. In this paper we describe our SAR efforts around 3, which were guided by insights from X-ray crystal structures on the binding mode of compounds as the series evolved. These resulted in a class of compounds, which efficiently suppressed IL-17 production in primary human cells and had favorable PK properties in rodent species.

Results and Discussion We succeeded in soaking compound 1 into the apo-crystals of RORγt-LBD, tethered to an SRC2 derived peptide, representing the agonist state of the receptor (Figure 2).24, 39 Recently, the


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co-crystal structures of 1 and of a closely related agonist, were published.50-52 Despite the different crystallization conditions, the key interactions of the compounds inside the ligand binding domain are very similar. These include the key hydrogen bond interaction of the sulfone oxygens with Arg367 and Gln286, and the amide moiety with the backbone carbonyl of Phe377. The amide bond is co-planar with the thiazole ring, with a stabilizing 1,5-O···S interaction.53 The meta-chloro substituent of the 4-aryl residue points to Ser404 (3.5 Å), and the side chain of Met365 has moved significantly (about 3.5 Å) with respect to the apo-structure.

Figure 2. a) X-ray structure of 1 (green) binding inside the RORγt LBD (gray) (2.30 Å, PDB: 5NI5). Compound 1 and key residues of the RORγt LBD are shown as sticks. b) Overlay of 1 (green) and 25-hydroxycholesterol (25-HC, grey), showing the interaction of 25-HC with the water molecule (dotted sphere) and the Tyr-His-lock. An overlay with 25-hydroxycholesterol (Figure 2b) shows that benzoyl group at the 5-position of the thiazole fills the hydrophobic pocket near helix 12 only partially, and does not interact with the so-called Tyr-His-lock, composed of His479 on helix 11 and Tyr502 on helix 12. These two residues which form part of the activation function 2 domain (AF2), the interaction site for


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co-regulatory proteins. We observed a conserved water near Trp317 and the His-Tyr-lock, which in the structure of the agonist 25-hydroxycholesterol interacts with the 25-hydroxy group, and stabilizes the agonist conformation.24 Stabilization of the AF2 domain by hydrophobic interactions was suggested as an explanation for the agonism of thiazole amides and keto amides.50, 52 For the inverse agonism of 1, a ‘water-trapping mechanism’ was proposed, whereby the release of the water molecule trapped at the AF2 domain in the hydrophobic environment is energetically favorable, leading to destabilization of helix 12.51 The X-ray structures described above were not published when we started our work, but the results in Table 1 pointed to a key role of the lipophilic benzoyl group for potency and activity in the cell assay. Assuming that the binding mode of 3 would closely resemble that of 1, we hypothesized that it should be possible to combine cell potency and achieve drug-like properties by using appropriate substituents appended to the thiophene-linked aryl group of 3. A focused library of compounds around the aryl substituent in the 4-position of the thiophene was prepared (Table 2). Addition of a cyano group in the 5-position of the 4-aryl group of 3 resulted in a 2-fold gain in potency. Moving the chlorine to the 2-position gave equipotent 5, which exhibited a lower partition coefficient compared to 4, whereas compound 6, with the cyano group into the 4-position, was less active. Trisubstituted derivative 7, bearing a methoxy group in place of the chlorine, gained another 2-fold in potency. Removal of the fluorine was tolerated, leading to 8, with an improved LLE value compared to 3. Another set of interesting data were provided by the ortho-substituted pyridyl analogues 9 and 10. Methoxy derivative 9 exhibited diminished binding activity with respect to 3, but maintained functional activity. A bulkier benzyl ether as in 10 led to a 20-fold gain in binding affinity, however 10 behaved as an agonist in the FRET assay, efficiently enhancing recruitment of the


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co-activator peptide. This indicated that our initial hypothesis of being able to modulate receptor function by proper substitution from the aryl group was at least partly correct. Attempts to further increase polarity of 9 as in pyrimidine 11 resulted in a significant loss in potency. Compound 12 combined the potency enhancing nitrile moiety with the methoxy group and similar to 8.

Table 2. Initial SAR around the 4-aryl group.

Cmpd

Ar

IC50 SPAa [µM]

IC50 FRETb [µM] (% eff.)

logDc / LLEd

3

3-Cl-Ph

0.11

0.18 (-96)

>4.1 / 4 / 4 / 3.3 67 3 (40%)

efficacy signify inhibition of IL-17 production; positive values a potentiation under the assay conditions. Effect of compound on cell viability or proliferation was assessed in the same assay with Cell-Titer-Glo® (CTG) measuring total ATP levels. bPermeability measured in Caco2 cells at pH=7.4/7.4. cPermeability measured in Caco2 cells incubated at pH=6.5 with a cocktail of inhibitors of common transporters. dBinding to human plasma protein determined by equilibrium dialysis. eDetermined from DMSO stock solutions in aqueous buffer at pH 7.4.


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We could obtain X-ray co-crystal structures of the inverse agonist 8 and agonist 10 by soaking the compounds into the apo crystals of RORγt-LBD (Figures 4), proving that the compounds bind to the receptor and are genuine modulators of RORγt.

Figure 4. Overlay of 1 and 8 (2.45 Å, PDB: 5NI7), 8 and 10 (1.94 Å, PDB: 5NI8), respectively, with key interactions to the RORγt-LBD. a) Compounds 1 (green), 8 (cyan) and key residues of the RORγ LBD are shown as sticks. b) Compounds 8 (cyan) and 10 (magenta) and key residues of the RORγt LBD are shown as sticks.

Both compounds showed an almost perfect overlap for the sulfone head group and the core heterocycle. The same key interactions as described above for 1, were established. For compound 8, the nitrile on the aryl moiety pointed towards the side-chain oxygen of Ser404, indicative of a rather long hydrogen-bond interaction of 3.2 Å, similar to the meta-Cl of the 4arylygroup of 1. The 2-methoxy group is too short to interact with the AF2 domain, whereas the benzyl group in agonist 10 filled the pocket around the His-Tyr lock, replacing the conserved water observed in the structures of 1 and 8. This hydrophobic interaction is thought to stabilize


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the agonist conformation of the AF2 domain and similar observations were published recently for other RORγ agonists.39, 50, 52, 57, 58 Based on the X-ray structure of 10, we expected that increasing the size of the alkoxy group would eventually lead to a clash with the His-Tyr-lock, and therefore to inverse agonism. Increasing the size of the alkoxy substituent from methoxy as in 9 to ethoxy as in 17 and subsequently to phenoxy as in 19 resulted in an increase in binding affinity and a gradual switch in function from inverse agonism to agonism in the FRET assay (Table 5), with 19 behaving like benzyl ether 10. Pushing the phenyl group out further by chain elongation of 10 did not lead to inverse agonism, but derivatives 20 and 21 behaved as agonists. We hypothesized that the flexibility of these substituents allowed them to be accommodated in the binding pocket, avoiding the steric clash with the AF2 domain. Rigidifying the propyl linker of 21 with a double bond supported this hypothesis, since cinnamyl ether 22 was a potent inverse agonist in the FRET assay. Introduction of a substituent to the para-position of the benzyl group of 10 led to the expected change in the mode of action. Ester 23 as well as benzonitrile 24 behaved as inverse agonists. Moving the cyano residue to the meta-position of the phenyl ring as in 25 led to a switch to agonistic behavior in the FRET assay. Table 5.

Cmpd

R1

R2

IC50 SPA[a] [µM]

IC50 FRET[b] [µM] (% eff.)

IC50 IL-17 Cell[c] [µM] (% eff.)

CTG [µM] (% eff)

RH Clint[d]

9

OMe

H

0.41

0.11 (-82)

n.t.

n.t.

13

10

OBn

H

0.020

+95% @ 3.3 µM

+38% @ 3.3 µM

>3 (30%)

128


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17

OEt

H

0.15

0.08 (-72)

-47% @ 1 µM

>10

28

18

OPr

H

0.059

-13% @ 3.3 µM

n.a.

3 (40)

80

19

OPh

H

0.046

+42% @ 3.3 µM

n.a.

3 (50)

196

20

O(CH2)2Ph

H

0.029

+84% @ 3.3 µM

+26% @ 1µM

3 (70)

125

21

O(CH2)3Ph

H

0.017

+17% @ 3.3 µM

>3.3 µM

3 (30)

104

22

OCH2CH=CHPh

H

0.011

0.029 (-90%)

0.025 (-78)

3 (40)

45

23

OCH2Ph-4-CO2Me

H

0.014

0.021 (-98)

0.035 (-92)

>10

>300

24

OCH2Ph-4-CN

H

0.01

0.03 (-57)

0.10 ± 0.08

>1 (50)

286

25

OCH2Ph-3-CN

H

0.019

+112% @ 3.3 µM

+5% @ 1 µM

0.3 (50)

281

26

OPh-4-CN

H

0.088

-18% @ 3.3 µM

0.19 ± 0.13 (-79)

>10

28

27

OCH2Ph-4-OCF3

H

0.007

0.03 (-68)

0.025 ± 0.09 (-68)

3 (40%)

40

28

OPh-4-OCF3

H

0.033

-19% @ 3.3 µM

0.144 ± 0.12 (-65)

>10

20

29

OCH2CF3

H

0.018

0.05 (-44)

0.10 ± 0.0 (-64%)

>10

17

OCH2CF3

CN

0.002

0.03 (-49%)

0.065 ± 0.03 (-66%)

>10

7.5

30 a

b

Displacement of tritiated ligand from human RORγt LBD (geometric mean n ≥ 2). Inhibition or activation of the

recruitment of SRC1-derived coactivator peptide (NCOA1 aa 677-700) to human RORγ LBD (geometric mean n ≥ 2); negative % efficacy (% eff.) values denote inverse agonism; positive values denote agonism and were determined at a single concentration. cInhibition of IL-17 production from human primary TH17 cells (geometric mean of n ≥ 3); negative values of % efficacy signify inhibition of IL-17 production; positive values a potentiation under the assay conditions. Effect of compound on cell viability or proliferation was assessed in the same assay with Cell-Titer-Glo® measuring total ATP levels; n.a.: not active at 3.3 µM; n.t.: not tested. dRat hepatocyte (µL min−1 (million cells)−1) metabolic intrinsic clearance.

Functional behavior in the FRET assay was mirrored in the cell assay, but the observed activity on IL-17A secretion was again obstructed by effects on cell viability for several compounds. Exceptions were cinnamyl ether 22 and ester 23 were at least a 100-fold window between cell activity and toxicity was observed. The added lipophilicity, compounds 17-25 have measured logD7.4 of around 4 or greater, came at the price of decreased metabolic stability, as the data from rat hepatocytes demonstrated. Removal of the metabolically labile methylene in benzyl ether 24 led to phenylether 26 with a


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lower logD7.4 value (3.6) and improved stability compared to either 19 or 24. Compound 26 behaved as an inverse agonist in the cell assay, where it exhibited an IC50 of 190 nM and no sign of cytotoxicity. Further SAR around the 4-phenyl substituent eventually identified the trifluoromethoxy group as an optimal group in the para-position. Benzylether 27 combined potent inhibition of IL-17A production with a 100-fold window over cytotoxicity and reasonable stability in rat hepatocytes. The corresponding phenylether 28 showed a further improvement in metabolic stability. It behaved like a weak partial inverse agonist in the FRET assay, as 26, but suppressed IL-17A secretion with an IC50 of 144 nM in the cell assay, with no effect on cell viability. We were also able to identify an inverse agonist with a short alkoxy side-chain by converting the ethoxy group of 17 to a bulkier trifluoroethoxy group. Compound 29 was a potent inhibitor of IL-17 production with no sign of cytotoxicity. Adding the nitrile group to the 5-position resulted in 30, showing a 10-fold increase in binding potency, an improvement in metabolic stability and a slight increase in cell potency. The maximum achievable inhibition in the cell assay reached a plateau at 66%, and most compounds in this series, apart from ester 23, did not completely abolish IL-17A production. We succeeded in soaking agonist 25 into the apo-crystal (Figure 5), and the only difference with respect to 10 concerned the orientation of the benzyl moiety. In compound 25, the phenyl ring was tilted in comparison to 10, filling a space between helices 11 and 7 and stabilizing the agonist form. Structurally related inverse agonists such as 23, 24 or 27 would be expected to push against the AF2-domain in either conformation, which was confirmed by the co-crystal structure of 23, described below. The sidechain of 30 is too short to interact directly with the


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helix 11/12 interface, but it seemed to disturb the conserved water, when we modelled it into the structure. Release of this water might destabilize the AF2 domain, as recently described for 1.51

Figure 5. Ligand interaction near the His-Tyr lock based on the structure of 25 (1.82 Å, PDB: 5NIB). Compounds 10 (magenta), 25 (yellow) and 30 (grey, modelled based on 8) and key residues of the His-Tyr lock of RORγt LBD are shown as sticks. The ligands are only shown partially for clarity. The conserved water position is shown as dotted sphere in red, and the position of the CF3 in 30 is shown as dotted sphere in cyan.

The co-crystal structure of 23 with the native RORγt construct in the absence of co-activator peptide,39 showed that the major interactions of 23 were the same as illustrated for 10 and 25, except for the benzoate ester group. In the agonist form, this group would clash with His479, as hypothesized above and indicated in Figure 6a. Consequently, part of helix 11 and the entire helix 12 are disordered and are missing from the electron density in the structure.


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Figure 6. Ligand interaction compound 23 in RORγt-LBD (2.37 Å, PDB: 6FGQ). a) Overlay of agonists 10 (magenta) and 25 (yellow) with inverse agonist 23 (orange). Key residues of the HisTyr lock of RORγt LBD are shown as sticks. The ligands are only shown partially for clarity. The conserved water position is shown as a dotted sphere in red. Helix 12 and part of helix 11 are disordered (indicated in the dashed circle) when compound 23 is bound. The putative steric clash between 23 and the side chain of His479 (based on 10 and 25) is shown as a red star (~1.4Å in between). b) Overlay of RORγt complexes of digoxin (PDB 3B0W, blue), 10 (magenta), and 23 (orange).

An overlay with the inverse agonist structure of digoxin showed a steric clash of ester 23 with His479, which in the digoxin structure is pulled in by the ligand, establishing a hydrogen-bond to one of its sugar hydroxy groups.25 This in turn “pushes” away part of helix 11 and all downstream residues. Overall, 23 seems to achieve the inverse agonist effect in a similar way, but without pulling in His479. Although we were not able to obtain a structure, we believe that phenylethers 26 and 28 exert their mode of action by a related mechanism. In summary, cell active agonists and two different types of inverse agonists can be obtained from the same


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template by the introduction of relatively minor structural changes to the alkoxy substituent. Similar results have been reported for a variety of diverse RORγ modulators.39, 52, 57-59

Figure 7: Structure overlay of RORγt in complex with compound 8 and PDB 5G45 (fragment bound). a): Compound 8 is shown as sticks with carbons in cyan, and the bound fragment and DMSO are shown with carbons in blue (DMSO depicted as sticks and spheres). b): surface view to illustrate the channel (“entrance”) to the LBP. The tethered SRC2 peptide is shown as a grey helix.

At this point, we had identified compounds 27-30, which demonstrated potent inhibition of IL17A release in primary human cells and showed good metabolic stability. However, they were still rather lipophilic, and attempts to introduce further polarity had failed. Fortunately, we were able to capitalize on a finding from our X-ray fragment screen.47 In a number of structures we had noted the presence of a DMSO site, which was near a conserved water position. The binding of DMSO occurred in a sub-pocket (a channel or “entrance” to the pocket) and its oxygen atom


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formed a hydrogen bond to the backbone NH of Glu379 (Figure 7). We saw this as an opportunity to endow our inhibitors with polar functionality. Modeling indicated that the carbonyl oxygen atom of an acetamide attached to the benzylic position of the phenylacetamide moiety would be able to mimic that interaction. We incorporated the acetamide into a set of compounds containing diverse 4-aryl residues, and found that this change was tolerated in all compounds investigated, leading to similar activity in SPA and FRET assays with respect to the parent compounds (Table 6). A reduction in lipophilicity was also achieved, accompanied by a higher stability in rat hepatocytes. To our surprise we found that compounds 31 and 32, the analogues of 12 and 7, respectively, also acquired activity in the cell assay, efficiently suppressing IL-17 production without an effect on cell viability. Compound 32 was about one order of magnitude more active than 31, with an IC50 of 57 nM. The unsubstituted amine 33 was significantly less potent in the binding and the cell assay, indicating that the acetyl residue in 32 had formed the desired interaction.

Table 6. Incorporation of an acetamide residue in 4-aryl-thienyl acetamides.

Cmpd

31

32

33

Ar *

*

*

R

IC50 SPA[a] [µM]

IC50 FRET[b] [µM] (% eff.)

IC50 IL-17 Cell[c] [µM] (% eff.)

Clint[d] RH

LogD /LLE[e]

NHAc

0.014

0.067 (-53)

0.99 (-55)

4

3.3 / 4.8

NHAc

0.009

0.063 (-72)

0.057 (-80)

5

3.3 / 4.8

NH2

0.075

0.452 (-62)

1.69 (-62)

11

3.2 / 3.9


20

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34

NHAc

0.066

0.055 (-52)

0.64 (-57)

10.4

3.4 / 3.7

NHAc

0.006

0.075 (-60)

0.032 (-77)

9.1

4.6 / 3.7

NHAc

0.007

0.072 (-60)

0.049 (-66)

4 / 33 / >33

nd

>33 / 19

>33 / >33

>33 / 9.4

>33 / 6.2

>33 / 0.6

RORβ IC50 [µM] [c]

nd

nd

>10

>10

>10

nd

>10

hERG (% inhib. @ 11 µM)

14

43

13

0

8

47

3

Cmpd Mw PSA (Å2) clogP /LLE [b]


24

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Solubility [µM] [d]

2.5

0.6

200

0.7

0.3

0.2

3.6

hPPB [%free][e]

Structure-based design leads to potent and orally bioavailable inverse

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