Discovery of phenoxyindazoles and phenylthioindazoles as RORγ inverse agonists

Discovery of phenoxyindazoles and phenylthioindazoles as RORγ inverse agonists

Bioorganic & Medicinal Chemistry Letters 26 (2016) 5802–5808 Contents lists available at ScienceDirect Bioorganic & Medicinal Chemistry Letters jour...

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Bioorganic & Medicinal Chemistry Letters 26 (2016) 5802–5808

Contents lists available at ScienceDirect

Bioorganic & Medicinal Chemistry Letters journal homepage: www.elsevier.com/locate/bmcl

Discovery of phenoxyindazoles and phenylthioindazoles as RORc inverse agonists Gilles Ouvry a,⇑, Claire Bouix-Peter a, Fabrice Ciesielski b, Laurent Chantalat a, Olivier Christin a, Catherine Comino a, Denis Duvert a, Christophe Feret a, Craig S. Harris a, Laurent Lamy a, Anne-Pascale Luzy a, Branislav Musicki a, Danielle Orfila a, Jonathan Pascau a, Véronique Parnet a, Agnès Perrin a, Romain Pierre a, Gaëlle Polge a, Catherine Raffin a, Yves Rival a, Nathalie Taquet a, Etienne Thoreau a, Laurent F. Hennequin a a b

Galderma R&D, Les Templiers 2400 Route des Colles, 06410 Biot, France NovAliX, Bld Sébastien Brant, Bioparc, 67405 Illkirch Cedex, France

a r t i c l e

i n f o

Article history: Received 20 September 2016 Revised 7 October 2016 Accepted 9 October 2016 Available online 12 October 2016 Keywords: ROR gamma Inverse agonists Phototoxicity Allosteric Topical administration

a b s t r a c t Targeting the IL17 pathway and more specifically the nuclear receptor RORc is thought to be beneficial in multiple skin disorders. The Letter describes the discovery of phenoxyindazoles and thiophenoxy indazoles as potent RORc inverse agonists. Optimization of the potency and efforts to mitigate the phototoxic liability of the series are presented. Finally, crystallization of the lead compound revealed that the series bound to an allosteric site of the nuclear receptor. Such compounds could be useful as tool compounds for understanding the impact of topical treatment on skin disease models. Ó 2016 Elsevier Ltd. All rights reserved.

The recent approval of Secukinumab1 for the treatment of moderate-to-severe psoriasis has firmly established the importance of the IL-17 axis in autoimmune disease and has vindicated the numerous approaches currently underway aimed at modulating this key inflammation pathway.2 Amongst these, modulating the Retinoic Acid Receptor-Related Orphan Receptor c (RORc, RORc or NR1F3) has generated a substantial interest from both academia and industry.3–5 Interested by the potential beneficial therapeutic impact of RORct inverse agonists6 on the treatment of skin diseases, including psoriasis,7 acne8 and atopic dermatitis,9 we embarked on a program aimed at discovering new RORct inverse agonists compatible with topical administration. At the time, only a few modulators had been described in the literature (Fig. 1).3d,10,11 Since then, an orally-administered and a topically-administered inverse agonist have now moved into Phase 2 clinical trials for the treatment of psoriasis.12 We were particularly interested by the series of indazoles disclosed by Merck.11,13,14 These relatively small inverse agonists (MW = 411 for compound 3, MW = 482 for 4; as opposed to

MW = 559 for 1) were all acidic, which could be seen as an interesting handle for future topical formulations. However, the heterocyclic amide linkage was seen as a potential liability from a formulation stability point of view. Indeed, ideally topical

Cl O S N Cl

SO2Et

O

http://dx.doi.org/10.1016/j.bmcl.2016.10.023 0960-894X/Ó 2016 Elsevier Ltd. All rights reserved.

OH

N H

N H

1

O

2 (TMP778) CO2H

CO2H

N

N Cl

N

N O

3 O Cl

⇑ Corresponding author.

O

O

N Cl

4 O Cl

Figure 1. Selection of RORct inverse agonists from the literature.

N

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G. Ouvry et al. / Bioorg. Med. Chem. Lett. 26 (2016) 5802–5808 CO2H

N R

formulations require months-long stability in solution and pH-sensitive groups can limit formulation options. We thus set out to find a suitable replacement for this part of the molecule. As part of our screening cascade, compounds were tested in a recombinant RORct/GAL4 transactivation cell-based assay as well as a RARc/GAL4 transactivation cell-based assay in order to get a first idea of their general nuclear receptor selectivity.15 ChromLogD at pH 6.5 was also determined for these compounds as a measure of lipophilicity.16

N

X R'

Figure 2. General structure of compounds presented in this manuscript.

Table 1 SAR of linker exploration CO2 H

N R5

N Cl

X Cl

a b c d

Compd

Linker (X)

R5

RORc GAL4 IC50 nMa

RARc GAL4 IC50 nMa

ChromLogD6.5 b/LipE

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

n/a n/a n/a n/a NH NH N-Me S S S(@O) S(@O) SO2 SO2 O O CH2

n/a n/a n/a n/a H CONMe2 H H CONMe2 H CONMe2 H CONMe2 H CONMe2 H

80 44 60 54 2500 3600 >10,000 2500 590 6200 >10,000 4800 >10,000 140 300 1800

>10,000 >10,000 1300 >10,000 >10,000 >10,000 —c 4400 >10,000 5600 >10,000 8400 >10,000 1400 >10,000 6800

5.2/1.9 4.7/2.6 2.4/4.8 1.3/6.0 1.9/3.7 0.9/4.5 2.6/– 2.9/2.7 1.6/4.6 1.2/4.0 0.4/– 1.8/3.5 0.9/– 2.8/4.0 1.5/5.0 2.8/3.0

d

See Supplementary Material for assay description.15 Geomean of at least 2 determinations. As determined by HPLC chromatography.16 Not tested. LipE: Lipophilic efficiency is determined by pIC50-ChromLogD.

O H N O

N

i)

R

17

O

ii) N

I

O

O

O

O

N

N

N

I

O

O

19

N

I

18a R=H 18b R=Me

O

N

Rb Ra

N O

22 (a-i)

iii)

OH

O

iii), iv)

O

O

OH

v), vi), iv) N Cl

S Cl

N HO O

N N Cl

S

21

Cl

N O

N

S

20 (a-h) Rc

Scheme 1. Synthesis of thioether analogs 20 and 22: (i) 4-Fluoro-benzoic acid tert-butyl ester, Cs2CO3, NMP, 120 °C (26%(18a), 20% (18b)); (ii) TBTU, Et3N, THF and HNMe2, room temperature (59%); (iii) substituted benzenethiol, phosphazene P2-Et, CuI, toluene, 110 °C (10–35%); (iv) TFA, DCM (80–95%); (v) pentafluorophenol, EDCI, DCM (99%); (vi) amine, DCM (40–85%).

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Table 2 SAR of R3 exploration CO2H

N N O

Compd

R3

N

R3

RORc GAL4 IC50 nMa

RARc GAL4 IC50 nMa

ChromLogD6.5b/LipE

590

>10,000

1.6/4.6

c

Cl

9

S Cl

20a

S

370

>10,000

1.6/4.8

20b

S

>10,000

3500

1.0/–

20c

S

>10,000

>10,000

1.4/–

20d

S

5000

>10,000

1.4/3.9

2700

>10,000

2.1/3.5

5900

>10,000

2.1/3.1

>10,000

>10,000

2.2/–

4300

>10,000

1.9/3.5

F

Cl

20e

S

20f

S

20g

S

Cl

Cl

Cl Cl Cl

20h

S Cl

a b c

See Supplementary Material for assay description.15 Geomean of at least 2 determinations. As determined by HPLC chromatography.16 LipE: Lipophilic efficiency is determined by pIC50-ChromLogD.

We started our approach by surveying different linkers on a reverse indazole scaffold (Fig. 2), which would abrogate the potential stability issue (Table 1). Compared to the indazole 3, anilinebased linkers showed reduced activity (5 and 6) while methylating the linking nitrogen (7) led to a loss of activity. Sulfur-based linkers were also explored and the thioether linker (8 and 9) gave the most consistent results, whereas sulfoxide (10 and 11) and sulfone linkers (12 and 13) tended to lose activity depending on indazole substitution. The ether linker gave the most potent analogs (14 and 15) with minimum added lipophilicity.17 While maintaining some activity, the carbon linker (16) was not pursued at the time due mainly to synthetic tractability. The dimethylamide subtituent in compound 4 from the original acylindazole series, was particularly interesting as it not only maintained a high level of potency with a significant reduction of lipophilicity (hence a boost in LipE), but also reduced RARc modulation. We were pleased to see that this could be fairly well reproduced on our inverse indazoles (compounds 9 and 15 in particular). The impact on broader nuclear receptor selectivity sug-

gested by the lack of activity on RARc prompted us to focus on amide-substituted compounds. Although slightly less potent then the ether-linked analogs, compound 9 was preferred as the starting point from a synthesis point of view, allowing a rapid exploration of the thiophenyl and the amide vectors. Using the following approach (Scheme 1), we were able to quickly map out SAR around this series. A synthesis was developed starting from methyl 3-iodo-1Hindazole-5-carboxylate 17 to prepare analogs 20 (a–h) and 22 (a-i).18 An SNAr on tert-butyl 4-fluorobenzoate using cesium carbonate in N-methylpyrrolidinone afforded a separable mixture of acid 18a and ester 18b. Amide formation from the acid gave dimethylamide intermediate 19. Copper-catalyzed thiophenol coupling was followed by tert-butyl deprotection to yield analogs 20 (a–h).19 Thioether 21 was obtained by copper-catalyzed thiophenol coupling on ester 18b,19 accompanied with concomitant saponification in situ. Synthesis and isolation of the pentafluoroester derivative provided an ideal intermediate for straightforward amide formation followed by tert-butyl ester deprotection.

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G. Ouvry et al. / Bioorg. Med. Chem. Lett. 26 (2016) 5802–5808 Table 3 SAR of R5 exploration CO2H

N R5

N Cl

S Cl

Compd

R5 N

9

RORc GAL4 IC50 nMa

RARc GAL4 IC50 nMa

ChromLogD6.5b/LipE

590

>10,000

1.6/4.6

>10,000

2700

1.2/–

6500

>10,000

1.9/3.3

>10,000

>10,000

0.8/–

>10,000

>10,000

2.9/–

2600

>10,000

1.9/3.7

1200

4100

1.7/4.2

720

>10,000

2.3/3.8

6000

4200

1.5/3.7

9200

7700

1.0/4.0

c

O H N

22a

O

N

22b

O

22c

N

HO

O N

22d

O N

22e

O

N

22f

O

F

F N

22g

O O N

22h

O N

22i

N O

a b c

See supplementary material for assay description.15 Geomean of at least 2 determinations. As determined by HPLC chromatography.16 LipE: Lipophilic efficiency is determined by pIC50-ChromLogD.

Key compounds with representative R3 variations are featured in Table 2. The bis-chloro substitution could be replaced by a bis methyl (20a) substitution with no significant change in potency or lipophilicity. Non-substituted thiophenol (20b) as well as mono-ortho substituted thiophenol (20c) lead to a drastic loss of potency. Replacing one of the chlorine atoms with a smaller fluorine atom (20d) also lead to a drop in potency. Exploring the other positions with either methyl groups or chlorine atoms (20e, 20f, 20g, 20h) further highlighted the preference for bis-ortho substitution in this series. The perpendicular orientation of the phenol ring induced by this di-substitution was confirmed as the bioactive conformation in the X-ray structure presented below. Similar results were reported by scientists at Genentech on a closely related series.11l Compounds with representative R5 variations are depicted in Table 3. Moving from the tertiary amide to the secondary amide (22a), had a deleterious effect on potency. Close analogs of the dimethyl amide with slightly bulkier groups (22b), hydrophilic groups (22c) or aromatic groups (22d) were not tolerated. Potency

was regained with cyclic analogs, with the smaller azetidine (22f) being preferred. The difluoroazetidine analog (22g) gave comparable potency to the dimethylamide starting point, albeit with an increase in lipophilicity. Polar cyclic amines like morpholine (22h) or piperazine (22i) led to a decreased activity. Results from the exploration of the thioether series suggested the dimethyl amide was optimal in the R5 position. The focus was shifted to the optimization of the ortho substitutents on the phenol group. Synthesis of two analogs is described in the scheme below (Scheme 2).18 A double SNAr approach was developed, allowing the rapid construction of the carbon skeleton of the desired molecules (intermediate 24). Reduction of nitro followed by saponification yielded aniline intermediate 25. Sandmeyer transformation followed by tert-butyl ester deprotection afforded methyl and trifluoromethyl analogs 26 and 27. We were pleased to see that both compounds displayed good potency, with 27 being more potent (Table 4). Activity in the transactivation assay translated quite well to an IL17 inhibition assay in

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G. Ouvry et al. / Bioorg. Med. Chem. Lett. 26 (2016) 5802–5808

O

O

Table 4 Lead ether compounds HO

H N O

NH

N N O

23

24

N R

N

O

N

N N O

26 R=Me 27 R=CF 3

O Cl

N N

O

OH

O

N N

N R

O

O

25

H2N

Scheme 2. Synthesis of ether analogs 26 and 27: (i) LiOH, THF, H2O (86%) (ii) Pentafluorophenol, EDCI, DMF, followed by Me2NH (2.0 M in THF) (98%); (iii) tertbutyl 4-fluoro-benzoate, Cs2CO3, NMP, 110 °C (54%); (iv) Substituted chloronitrobenzene, K2CO3, NMP, 110 °C (20–35%); (v) AcOH, Fe, 70 °C (98%); (vi) CuCl2, isoamylnitrite, acetontrile, 0 °C (10–25%); (vii) TFA, DCM (95%).

CD4 cells.15 Selectivity against RARc was maintained and good to excellent selectivity was achieved with 27 against an in-house panel of nuclear hormone receptors. Intrinsic clearance in human hepatocytes was high. The compounds were also unstable in rat microsomes. This is considered a benefit from a topical design perspective as the pharmacological effect would be confined to the skin and not due to a systemic contribution. These compounds would therefore be good tool compounds to document local effect after topical application. Pleasingly, 27 was found to be completely stable after 3 months at 40 °C in a PG:EtOH 96 (7/3) mixture. To our disappointment, with phototoxic irritancy factors above 5, both compounds turned out to be positive in our phototoxicity assay.15,20,21Although a positive result should not be regarded as a final assessment of a compound’s phototoxic liability in the clinic, it would warrant further investigation in vivo.20 Further investigation was performed on this class of compounds and it was discovered that the vast majority of compounds tested, were positive in this assay regardless of linker, aromatic phenol or thiophenol substitution and amide.22 At this stage we decided to tackle the phototoxicity liability by thoroughly exploring the electronics and the degree of conjugation of the p-system of our molecules (Table 5).23 Methyl groups or fluorines (28a, 28b, 28c, 28d) were introduced at R4 and R7 positions in order to impact the conformation of these compounds. Although fluorines turned out to be interesting from a potency point of view, none of these changes affected the phototoxic nature of this series. Switching the amide to the R6 position (28e) or replacing the amide by a nitrile (28f) or a sulfone (28g) had no impact on the phototoxicity while having a deleterious effect on potency. meta-Substitution (28h, 28i)17 and disubtitution (28j) on the benzoic acid ring was tolerated in terms of activity but still showed no effect on phototoxicity. We next turned our attention to the introduction of sp2-nitrogens to document their possible impact. 7-Azaindazoles (29) and 4-azaindazoles (30) maintained a reasonable level of potency accompanied by an expected drop in lipophilicity. Unfortunately, the impact on phototoxicity remained minimal. The same could be said for pyridine versions of the benzoic acid part of the mole-

RORc GAL4 IC50 nMa Hu CD4 IL17 nMa RARc GAL4 IC50 nMa RORa GAL4 IC50 nMa LXRb Kdapp nMa VDR Kdapp nMa PPARc Kdapp nMa ChromLogD6.5b LipEe Fu (Hu)a Hu Hep Clint (lL/ min/1e6 cells)a Stability in PG/ EtOH96 (3/7)f Phototoxic irritation factora,d

N Cl

O

O

F3 C

26

v)

vi), vii) N R

N Cl

O

O

O 2N

O

O

i), ii), iii), iv)

O

O

HO

O

27

120

31

150 >10,000

40 7200

>10,000

>10,000

—c —c —c 1.5 5.5 2.4% 54

>10,000 >10,000 4000 1.6 5.9 1.5% 30

—c

>98%

36

21

a See Supplementary Material for assay description.15 Geomean of at least 2 determinations. b As determined by HPLC chromatography.16 c Not tested. d PIF (phototoxic irritation factor) is determined as a the ratio between IC50 with UV/IC50 without UV.15,20,21 e LipE: Lipophilic efficiency is determined by pIC50-ChromLogD. f % compound remaining after 3 months at 40 °C at 0.01% w/v.

cule (31 and 32). Pyrazole 33 maintained some activity considering the drop in lipophilicity. Unfortunately, this did not lead to a change in the phototoxic nature of this series. Inactive intermediate 34, with the benzoic acid moiety removed altogether, was screened and found to be not phototoxic. With this in mind, compounds 35 and 36 were synthesized. Unfortunately, the non-phototoxic nature observed for 34 did not carry over to the saturated analogs. Scientists at LEO Pharma have recently highlighted a photo-instability of some unrelated indazole compounds.24 Further work would be required to validate this hypothesis on our series. It is unknown if recent compounds from closely related RORc modulators published by scientists at Glenmark, Genentech, Advinus, Daichi and Merck containing different bicyclic cores and/or 4-carboxyl piperidines would behave differently in similar phototoxicity assays.13 In parallel to this work on the phototoxicity of our series, we were able to get a crystal structure of our lead compound 27.25 This yielded an unexpected result. Indeed, the compound bound the receptor in a different manner from known RORc modulators at the time. Compound 27 induces its own binding pocket, located between Helixes 3, 4 and 11. The other faces are delimited on one side by the orthosteric site and on the opposite side by Helix12 which folds back against the core of the LBD in a fixed antagonist pose, different from the agonist conformation and not compatible with co-activator binding. No overlap between the orthosteric site and this allosteric site is observed. Merck scientists have since published the crystal structure of close analogs of 3 with similar binding modes (without the amide substituent) confirming the allosteric nature of these modulators.12

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G. Ouvry et al. / Bioorg. Med. Chem. Lett. 26 (2016) 5802–5808 Table 5 Ether indazole scaffold exploration CO2H R

R

7

R6

CO2H

CO2H

R5 4

CO2H

CO2H

CO2H

CO2H

N

1'

R N

R

CO2H

1"

N N

N Cl

N

O

N N Cl

O

Cl

N

N Cl

O

Cl

28 (a-j)

N

O

Cl

29

N Cl

Cl

30

31 0

Compd

R4

R5

R6

R7

R1

14 28a 28b 28c 28d 28e 28f 28g 28h 28i 28j 29 30 31 32 33 34 35 36

— Me H F H H H H H H H — — — — — — — —

— H H H H H CN SO2Me H H H — — — — — — — —

— H H H H C(O)NMe2 H H H H H — — — — — — — —

— H Me H F H H H H H H — — — — — — — —

— H H H H H H H Me F F — — — — — — — —

00

N

N N Cl

O

O Cl

32

H N

N

N Cl

O

N N

Cl

33

34

N

N Cl

O Cl

35

N

N Cl

O Cl

36

R1

RORc GAL4 IC50 nMa

RARc GAL4 IC50 nMa

ChromLogD6.5 b/LipEe

Phototoxic irritation factord

— H H H H H H H H H F — — — — — — — —

140 820 >10,000 260 88 >10,000 >10,000 >10,000 3600 240 310 2100 1200 1100 >10,000 4800 >10,000 >10,000 >10,000

1400 1100 >10,000 800 7600 >10,000 1400 4500 6200 >10,000 >10,000 6800 3800 1900 >10,000 9100 5700 >10,000 >10,000

2.8/4.0 3.6/2.5 2.6/– 2.8/3.8 2.8/4.3 1.8/– 2.6/– 1.7/– 3.0/2.4 2.8/3.8 2.9/3.6 1.3/4.4 2.3/3.6 2.9/3.1 3.7/— 1.6/3.7 4.9/– 3.4/– 3.1/–

>62 19 c >90 30 18 138 87 41 32 16 11 190 90 30 121 1.6 108 41

a

See Supplementary Material for assay description.15 Geomean of at least 2 determinations. As determined by HPLC chromatography.16 c Not tested. d PIF (phototoxic irritation factor) is determined as a the ratio between IC50 with UV/IC50 without UV.19 e LipE: Lipophilic efficiency is determined by pIC50-ChromLogD. b

Figure 4. Non-bonding interaction between amide nitrogen and Lys354.

Figure 3. X-ray structure of compound 27 (orange) with RORg (green) (PDB code: 5LWP). The pink surface delineates the extent of the orthosteric site calculated from an agonist co-crystal structure PDB:4NIE).

Figure 3 depicts key interactions compound 27 makes with the receptor. The carboxylate makes three hydrogen bonds with the backbone nitrogens of Phe 498 and Ala 497 from Helix12 and the side chain of Gln 329 from Helix3. Pi–Pi stacking is observed between the phenoxy ring and Phe506. This interaction is strengthened by the edge to face contact made between the ben-

zoic acid and Tyr 502 from Helix12. The dimethylamide carbonyl makes a hydrogen bond with backbone NH of Met 358 at the hinge between Helix4 and Helix5. One unusual interaction was found between the carbonyl of Lys354 and the nitrogen atom of the dimethyl amide. It appears as if the HOMO of the ligand’s amide nitrogen interacts with the LUMO of Lys 354’s carbonyl (Fig. 4). Intrigued, we data-mined the CSD and were able to find similar interactions.26 Somewhat related halogen bond interactions implicating the HOMO of an amide’s nitrogen have been described recently.27

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In conclusion, we have identified phenoxyindazoles and phenylthioindazoles as potent, allosteric, inverse agonists of RORc. These compounds were optimized to yield potent analogs 26 and 27. Compound 27 displayed a good profile for a topically applied tool compound. It was also found that this series of compounds carried a phototoxic flag, which we were unable to address despite considerable efforts. This would warrant further investigation in vivo. A crystal structure of this series of modulators (compound 27) was obtained and showed these bound to an allosteric site in RORc.

11. 12. 13.

Acknowledgments We thank Grégoire Mouis and Michèle Aurelly for analytical support. Supplementary data Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.bmcl.2016.10. 023. These data include MOL files and InChiKeys of the most important compounds described in this article. References and notes 1. http://www.accessdata.fda.gov/drugsatfda_docs/nda/2015/125504Orig1s000 MedR.pdf. 2. General reviews (a) Kojetin, D. J.; Burris, T. P. Nat. Rev. Drug Disc. 2014, 13, 197; (b) Kamenecka, T. M.; Lyda, B.; Chang, M. R.; Griffin, P. R. Med. Chem. Commun. 2013, 4, 764. 3. (a) Banerjee, D.; Zhao, L.; Wu, L.; Palanichamy, A.; Ergun, A.; Peng, L.; Quigley, C.; Hamann, S.; Dunstan, R.; Cullen, P.; Allaire, N.; Guertin, K.; Wang, T.; Chao, J.; Loh, C.; Fontenot, J. Immunology 2016, 147, 399; (b) Skepner, J.; Trocha, M.; Ramesh, R.; Qu, X. A.; Schmidt, D.; Baloglu, E.; Lobera, M.; Davis, S.; Nolan, M. A.; Carlson, T. J.; Hill, J.; Ghosh, S.; Sundrud, M. S.; Yang, J. Immunology 2015, 145, 347; (c) Xiao, S.; Yosef, N.; Yang, J.; Wang, Y.; Zhou, L.; Zhu, C.; Wu, C.; Baloglu, E.; Schmidt, D.; Ramesh, R.; Lobera, M.; Sundrud, M. S.; Tsai, P. Y.; Xiang, Z.; Wang, J.; Xu, Y.; Lin, X.; Kretschmer, K.; Rahl, P. B.; Young, R. A.; Zhong, Z.; Hafler, D. A.; Regev, A.; Ghosh, S.; Marson, A.; Kuchroo, V. K. Immunity 2014, 40, 477; (d) Skepner, J.; Ramesh, R.; Trocha, M.; Schmidt, D.; Baloglu, E.; Lobera, M.; Carlson, T.; Hill, J.; Orband-Miller, L. A.; Barnes, A.; Boudjelal, M.; Sundrud, M.; Ghosh, S.; Yang, J. J. Immunol. 2014, 192, 2564. 4. Representative references (a) Chao, J.; Enyedy, I.; Van Vloten, K.; Marcotte, D.; Guertin, K.; Hutchings, R.; Powell, N.; Jones, H.; Bohnert, T.; Peng, C.-C.; Silvian, L.; Hong, V. S.; Little, K.; Banerjee, D.; Peng, L.; Taveras, A.; Viney, J. L.; Fontenot, J. Bioorg. Med. Chem. Lett. 2015, 25, 2991; (b) Wang, T.; Banerjee, D.; Bohnert, T.; Chao, J.; Enyedy, I.; Fontenot, J.; Guertin, K.; Jones, H.; Lin, E. Y.; Marcotte, D.; Talreja, T.; Van Vloten, K. Bioorg. Med. Chem. Lett. 2015, 25, 2985; (c) Muegge, I.; Collin, D.; Cook, B.; Hill-Drzewi, M.; Horan, J.; Kugler, S.; Labadia, M.; Li, X.; Smith, L.; Zhang, Y. Bioorg. Med. Chem. Lett. 1892, 2015, 25; (d) Fauber, B. P.; René, O.; Deng, Y.; DeVoss, J.; Eidenschenk, C.; Everett, C.; Ganguli, A.; Gobbi, A.; Hawkins, J.; Johnson, A. R.; La, H.; Lesch, J.; Lockey, P.; Norman, M.; Ouyang, W.; Summerhill, S.; Wong, H. J. Med. Chem. 2015, 58, 5308. 5. For general reviews on ROR c inverse agonist, see: (a) Cyr, P.; Bronner, S. M.; Crawford, J. J. Bioorg. Med. Chem. Lett. 2016, 26, 4387; (b) Fauber, B. P.; Magnusson, S. J. Med. Chem. 2014, 57, 5871. 6. The compounds in this manuscript are described as inverse agonist. To our knowledge, the endogenous RORc ligand is unknown. Thus it is unclear if RORc is constitutively active in our assay (in which case we would measure inverse agonism) or not (in which case we would measure antagonism). Both terms are found in the literature to describe RORc modulators. 7. Smith, S. H.; Peredo, C. E.; Takeda, Y.; Bui, T.; Neil, J.; Rickard, D.; Millerman, E.; Therrien, J.-P.; Nicodeme, E.; Brusq, J.-M.; Birault, V.; Viviani, F.; Hofland, H.; Jetten, A. M.; Cote-Sierra, J. PLoS One 11, e0147979, doi: http://dx.doi.org/10. 1371/journal.pone.0147979. 8. Kelhälä, H. L.; Palatsi, R.; Fyhrquist, N.; Lehtimäki, S.; Väyrynen, J. P.; Kallioinen, M.; Kubin, M. E.; Greco, D.; Tasanen, K.; Alenius, H.; Bertino, B.; Carlavan, I.; Mehul, B.; Déret, S.; Reiniche, P.; Martel, P.; Marty, C.; Blume-Peytavi, U.; Voegel, J.J.; Lauerma, A. PLoS One 9, e105238, doi: http://dx.doi.org/10.1371/ journal.pone.0105238. 9. Koga, C.; Kabashima, K.; Shiraishi, N.; Kobayashi, M.; Tokura, Y. J. Invest. Dermatol. 2008, 128, 2625. 10. (a) Wang, Y.; Cai, W.; Zhang, G.; Yang, T.; Liu, Q.; Cheng, Y.; Zhou, L.; Ma, Y.; Cheng, Z.; Lu, S.; Zhao, Y.-G.; Zhang, W.; Xiang, Z.; Wang, S.; Yang, L.; Wu, Q.;

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WO2014/028597, 2014; (c) Barr, K. J.; Beinstock, C.; Maclean, J.; Zhang, H.; Beresis, R. T.; WO2014/028591, 2014; (d) Barr, K. J.; Beinstock, C.; Maclean, J.; Zhang, H.; Beresis, R. T.; Zhang, D. WO2014/028589, 2014; (e) Barr, K. J.; Maclean, J.; Zhang, H.; Beresis, R. T.; WO2014/026330, 2014; (f) Barr, K. J.; Beinstock, C.; Maclean, J.; Zhang, H.; Beresis, R. T.; WO2014/026329, 2014; (g) Barr, K. J.; Maclean, J.; Zhang, H.; Beresis, R. T.; Zhang, D. WO2014/026328, 2014; (h) Barr, K. J.; Beinstock, C.; Maclean, J.; Zhang, H.; Beresis, R. T.; Zhang, D. WO2014/026327, 2014 (i) Das, S.; Thomas, A.; Khairatkar-Joshi, N.; Shah, D. M.; Bajpai, M. WO2015/052675, 2015; (j) Chaudhari, S. S.; Thomas, A.; Shone, S. V.; Khairatkar-Joshi, N.; Bajpai, M. WO2015/008234, 2015; (k) Das, S.; Chaudhari, S. S.; Thomas, A.; Pardeshi, S. R.; Deshmukh, V. G.; Wadekar, P. D.; Khairatkar-Joshi, N.; Shah, D. M.; Bajpai, M. WO2015/087234, 2015; (l) Fauber, B. P.; Gobbi, A.; Robarge, K.; Zhou, A.; Barnard, A.; Cao, J.; Deng, Y.; Eidenschenk, C.; Everett, C.; Ganguli, A.; Hawkins, J.; Johnson, A. R.; La, H.; Norman, M.; Salmon, S.; Ouyang, W.; Tang, W.; Wong, H. Bioorg. Med. Chem. Lett. 2015, 25, 2907; (m) Fauber, B. P.; Gobbi, A. WO2015/ 036411, 2015 (n) Hai; X.; Yu, F.; Ma, T.;Cha, M. Y. WO2015/139621, 2015; (o) McCarthy, C.; Went, N. WO2016/063080, 2016; (p) McCarthy, C.; Went, N. WO2016/063081, 2016; (q) Mukhopadhyay, P.; Munot, Y.; Shaikh, N.; Kulkarni, B. A.; Mookhtiar, K. WO2016/110821, 2016; (r) Shaikh, N.; Mukhopadhyay, P.; Munot, Y.; Kulkarni, B. A.; mookhtiar, K. WO2016/128908, 2016; (s) Nagamochi, M.; Furusawa, Y.; Inagaki, H.; Gotanda, T.; Noguchi, S.; Torihata, M.; Yoshino, T.; Isobe, T. JP2016/141632, August 8, 2016; (t) Lapointe, B. T.; Fuller, P. H.; Gunaydin, H.; Liu, K.; Sciammetta, N.; Trotter, B. W.; Zhang, H.; Barr, K. J.; Maclean, J. K. F.; Molinari, D. F.; Simov, V. WO2016/130818, 2016. Scheepstra, M.; Leysen, S.; van Almen, G. C.; Miller, J. R.; Piesvaux, J.; Kutilek, V.; van Eenennaam, H.; Zhang, H.; Barr, K.; Nagpal, S.; Soisson, S. M.; Kornienko, M.; Wiley, K.; Elsen, N.; Sharma, S.; Correll, C. C.; Trotter, B. W.; van der Stelt, M.; Ouvrie, A.; Ottmann, C.; Parthasarathy, G.; Brunsveld, L. Nat. Commun. 2015, 7, 8833. A detailed description of all of the assays is available in the supplementary material. ChromLogD6.5 was calculated from an HPLC measured Chromatographic Hydrophobicity Index at pH 6.5 using the following equation: ChromLogD6.5 = 0.086*CHI6.5–3.5. pH 6.5 is used to mimick the more acidic nature of skin. For additional references on CHI, see: Young, R. J.; Green, D. V. S.; Luscombe, C. N.; Hill, A. P. Drug Discovery Today 2011, 16, 822. As we were working on this series, compounds 14 and 28i were disclosed in the following patent application: Das, S.; Chaudhari, S. S.; Thomas, A.; Pardeshi, S. R.; Deshmukh, V. G.; Wadekar, P. D.; Khairatkar-Joshi, N.; Shah, D. M.; Bajpai, M. WO2015/087234, 2015. A detailed description of the syntheses of all the compounds described here is available in the Supporting information. Palomo, C.; Oiarbide, M.; Lόpez, R.; Gόmez-Bengoa, E. Tetrahedron Lett. 2000, 41, 1283. For FDA guidelines regarding phototoxicity see: http://www.fda.gov/ downloads/drugs/guidancecomplianceregulatoryinformation/guidances/ucm3 37572.pdf. Based on https://ntp.niehs.nih.gov/iccvam/suppdocs/feddocs/oecd/oecdtg432508.pdf, a test substance with a PIF <2 predicts: ‘no phototoxicity’. A PIF >2 and <5 predicts: ‘probable phototoxicity’ and a PIF >5: ‘phototoxicity’. See Supplementary material for more details. Compounds 3, 8, 9, 11, 13, 20a, 20d, 20f and 20g tested all positive in the phototoxic assay. For reference on models to predict risks of phototoxicity, see: (a) Ringeissen, S.; Marrot, L.; Note, R.; Labarussiat, A.; Imbert, S.; Todorov, M.; Mekenyan, O.; Meunier, J.-R. Toxicol. In Vitro 2011, 25, 324; (b) Peukert, S.; Nunez, J.; He, F.; Dai, M.; Yusuff, N.; DiPesa, A.; Miller-Moslin, K.; Karki, R.; Lagu, B.; Harwell, C.; Zhang, Y.; Bauer, D.; Kelleher, J. F.; Egan, W. MedChemComm 2011, 2, 973. A recent publication describes phototoxicity associated with indazoles Ritzén, A.; Sørensen, M. D.; Dack, K. N.; Greve, D. R.; Jerre, A.; Carnerup, M. A.; Rytved, K. A.; Bagger-Bahnsen, J. ACS Med. Chem. Lett. 2016, 7, 641. Experimental data associated with compound 27 co-crystallised with ROR c are described in the Supplementary data. PDB code: 5LWP. Datamining the CSD for this type of interaction yielded 219 hits, where the carbonyl oxygen and the amide nitrogen are within contact distance of each other. See Supplementary material for more information. Zimmermann, M. O.; Boeckler, F. M. MedChemComm 2016, 7, 500.