discovery & optimisation of novel agonists of gpr119discovery & optimisation of novel...

Discovery & Optimisation of

Novel Agonists of GPR119:

James S. Scott

AstraZeneca

Alderley Park, UK

[email protected]

17th RSC/SCI Medicinal Chemistry

Symposium

R&D | CVGI | AP Jamie Scott| 04 2012

Outline of talk

• Introduction to target and start point

• Cyanopyridyl as a replacement for sulphone

• Improving solubility

• Seizure assay and a return to the sulphone…..

• A hERG beating methylene

• Summary and learning


• Enhanced incretin (GLP-1) secretion and direct effect on pancreas

• ‘Oral GLP-1’ concept – combination opportunity with DPPIV inhibitors

GPR119 as a target for diabetes

• Class A GPCR (deorphanised)

• Expression reported in pancreas, gut, (brain)

• Targeting an Agonist

[Shah, U. RSC Drug Discovery

Series, 2012, Chapter 7]


When something is too good to be true....

N

N

O

F3C

S

O O

N

N

OS

O O

F

S

N

Stop Series

hGPR119 pEC50 6.3 (42%)* hGPR119 pEC50 7.6 (44%)

hERG IC50 2.5 mM hERG IC50 16 mM

logD 2.9 logD 2.1

• Robust Glucose lowering

• But also in GPR119 knock-out mice.....

• Off target activity

*cAMP potency EC50 with intrinsic activity (% effect) relative to 50 mM oleoylethanol amide (OEA; endogenous ligand)

[Bioorg. Med. Chem. Lett. 2011, 21, 7310.]


ON

N

NN

O

O S

OO

pEC50 7.2 (83%)*

Sol 0.03 mM [c]

logD 3.2

hERG >33 mM

Potency in mouse similar

pEC50 7.3 (99%)

No hERG and on target efficacy

3x

1000x

A) Sulphone

increase

needed

Plan B - A second series.....

*cAMP potency EC50 with intrinsic activity (% effect) relative to 50 mM oleoylethanol amide (OEA; endogenous ligand)


ON

N

N

N

NO

O

ON

N

NN

O

O S

OO

pEC50 7.2 (83%)

Sol 0.03 mM [c]

logD 3.2

hERG >33 mM

Potency in mouse similar

pEC50 7.3 (99%)

Key issues to address: Solubility / Potency / logD / Boc group

No hERG and on target efficacy

pEC50 6.2 (71%)

Sol 23 mM [c]

logD 3.4

hERG >33 mM

3x

1000x

Pyridyl N acting as acceptor

(but less optimal than SO2Me)

A) Sulphone B) Pyridine

• Pharmacophoric elements are lipophile (often carbamate) and acceptor

• Struggled to move from neutrals and retain potency

increase

needed 30x

3x

increase

needed

Plan B - A second series.....


ON

N

NN

O

O S

OO

Sol 0.03 mM [c]

logD 3.2

• Molecules pack – end to end via

sulphone – sulphone interactions

And in ladder interactions

• Seen in 1/4 of sulphones in CSD

A) Understanding the insolubility of the sulphone

End-End 18%

Ladder 18%

Both 23%

None 41%


Acceptor SAR – around pyridyl

O

ON ON

N

N

N

R

• Summary of pyridine SAR with lines of

constant pEC50-logD

Ligand Lipophilic Efficiency (LLE)

Sized by intrinsic activity (10-155%)

• CN represents a breakthrough!

pEC50 6.2 (71%)

Sol 23 [c]

logD 3.4

LLE 2.8

N

pEC50 <5.7

Sol 66 [c]

logD 3.7

N

pEC50 7.1(101%)

Sol 4 [c]

logD 3.8

LLE 3.3

N • 2-substitution potency

• 3-substitution potency

B) Optimisation of pyridine

GP

R11

9 p

EC

50

logD

ON

N

N

N

NO

O

LLE=2

LLE=3

LLE=4 LLE=5


ON

N

N

N

NO

O

pEC50 6.2 (71%)

Sol 23 mM

logD 3.4

LLE 2.8

ON

N

N

N

NO

O

N

pEC50 7.7 (155%)

Sol 32 mM

logD 2.8

LLE 4.9

ON

N

N

N

NO

O

pEC50 6.7 (68%)

Sol 45 mM

logD 3.8

LLE 2.9

Me adds potency (& logD)

CN adds potency (& lowers logD)

Bringing it all together


ON

N

N

N

NO

O

pEC50 6.2 (71%)

Sol 23 mM

logD 3.4

LLE 2.8

ON

N

N

N

NO

O

N

ON

N

N

N

NO

O

N

pEC50 7.7 (155%)

Sol 32 mM

logD 2.8

LLE 4.9

ON

N

N

N

NO

O

pEC50 6.7 (68%)

Sol 45 mM

logD 3.8

LLE 2.9

pEC50 8.2 (171%)

Sol 21 mM

logD 3.3

LLE 4.9

Me adds potency (& logD)

CN adds potency (& lowers logD)

100x potency improvement

LogD neutral

Solubility maintained


Bringing it all together


ON

N

N

N

NO

O

N


NO

NON

N

N

N

N

N

F3C

pEC50 8.2 (171%)

Sol 21 mM

logD 3.3

LLE 4.9

pEC50 8.7 (243%)

Sol 3 mM

logD 4.0

LLE 4.7

Oxadiazole as an isostere for Boc

• Compound is active in vivo

in wild-type BUT NOT knock-out mouse

• Glucose & GLP-1 endpoints

On target efficacy

NO

NON

N

N

N

N

N

pEC50 8.1 (199%)

Sol 7uM

logD 3.3

LLE 4.8


Improving Solubility #1 - An alternative to Boc.


ON

N

N

N

NO

O

N

pEC50 8.2 (171%)

Sol 21 mM

logD 3.3

LLE 4.9

pEC50 7.7 (171%)

Sol 110uM

logD 2.5

LLE 5.2

ON

N

N

N

NO

O

N

O

CF3ON

N

N

N

NO

O

N

O

pEC50 5.9 (95%)

Sol 690uM [c]

logD 1.9

LLE 4.0

Strong ether acceptor not

satisfied by any H-bond donors


Improving Solubility #2 - Not all oxadiazoles are equal...

Acceptor scales - logKb

[Abraham et al. J. Chem. Soc., Perkin Trans. 2, 1989, 1355.]

Subsequently shown to correlate with electrostatic potential by

[Kenny, P.; J. Chem. Soc., Perkin Trans. 2, 1994, 199.]

NO

OPh

2.1

NO

NN

F3C

0.4

-0.8

ON

NN

F3C

0.2

0.4

NN

ON

F3C

1.4 1.0


NO

NON

N

N

N

N

N

F3C

pEC50 8.7 (243%)

Sol 3 mM

logD 4.0

LLE 4.7

NN

OON

N

N

N

N

N

F3C

pEC50 7.6 (220%)

Sol 120 mM

logD 2.7

LLE 4.9

[Boström, J et al J. Med. Chem., 2011, 1817]

pEC50 8.3 (236%)

Sol 5uM

logD 3.1

LLE 5.2

ON

NON

N

N

N

N

N

F3C

R&D | CVGI | AP Jamie Scott| 04 2012 14

Riding the line of LLE down to improve properties

ON

N

N

N

N

N

F3C

Hu

EC50

(uM) LogD

LLE

pEC50

-logD

Mouse

PPB

(%)

hERG

IC50

(uM)

Sol

(uM)

0.002 4.0 4.7 1.2 7 3.1 [c]

0.005 3.1 5.2 3.8 6 4.8 [c]

0.026 2.7 4.9 11 18 120 [c]

N

NO

NF

3C

N

ON

NF

3C

N

NN

OF

3C

1

2

3

GP

R11

9 p

EC

50

logD

LLE=5

• Control of lipophilicity by oxadiazole isomer

• Big impact in terms of solubility

• Benefits in terms of hERG

• Loss in potency offset by increased free levels

Potency vs logD

[MedChemCommun., 2013, 4, 95]


Problems seen in mouse toxicity studies

Clonic convulsions in 2 mice (day 10 @ 300mpk) whilst undergoing an IRWIN assessment

NO

NON

N

N

N

N

N

• Seizure: synchronized abnormal neuronal activity that may result in a number of behavioral

symptoms including tonic-clonic convulsion

• Convulsion: the behavioral consequence of a seizure – typically muscle rigidity followed by rhythmic

jerking movements

• Convulsion ≠ seizure

• Abnormal motor events, syncopal events, etc. may be incorrectly mistaken for convulsions

How can we find a back-up compound?


• Evoked population spike: Summated firing of CA1

pyramidal neurones (measure of cell excitability and

underlying synaptic activity)

• Potentially seizurogenic compounds can induce

excitatory effect by variety of potential mechanisms

In vitro Brain Slice

[Easter A. et al., J Pharmacol Toxicol Methods. 2007, 56, 223]


• Evoked population spike: Summated firing of CA1

pyramidal neurones (measure of cell excitability and

underlying synaptic activity)

• Potentially seizurogenic compounds can induce

excitatory effect by variety of potential mechanisms

In vitro Brain Slice

[Easter A. et al., J Pharmacol Toxicol Methods. 2007, 56, 223]

Compound caused a

concentration-dependent

increase in excitability,

consistent with a

convulsant compound


Results from Brain Slice Assay

NO

NON

N

N

N

N

N

NN

OON

N

N

N

N

N

F3C

+ve Brain slice

logD 3.3

+ve Brain slice

logD 2.7

NO

NON

N

N

N

N

N

F3C

+ve Brain slice

logD 4.0

Matched Pair

S

OO

NN

OON

N

NN

F3C

F

-ve Brain slice

logD 3.0

• Future compounds should not contain a CN pyridyl to avoid this issue

• Impact is that achieving high solubility will be challenging.....

• & compounds may have a hERG issue.....

pEC50 7.6 (220%)

logD 2.7

Sol 140uM

hERG 18uM

pEC50 7.6 (121%)

logD 3.0

Sol 1uM

hERG 7uM


hERG can be circumvented – the CH2SO2Me!

pEC50 7.6 (121%)

logD 3.0

hERG 7uM

NN

OF3C

ON

N

NN

S

OO

F

‘Unlucky’ here – can we fix it?

hERG can be difficult to predict

- Structure driven rather than logD

- Small changes can have a big effect

Circumventing hERG GPR119 hERG



pEC50 7.6 (121%)

logD 3.0

hERG 7uM

NN

OF3C

ON

N

NN

S

OO

F

pEC50 7.6 (100%)

logD 2.9

hERG >33uM

SO O

NN

OF3C

ON

N

NN

F

pEC50 8.4 (89%)

logD 3.6

hERG 4uM

ON

NF3C

ON

N

NN

S

OO

F

CH2 spacer to polar sulphone

removes hERG liability

(potency and logD neutral)

Oxadiazole isomer

raises logD (increases

potency & hERG)







SO O

ON

NF3C

ON

N

NN

F


pEC50 7.6 (121%)

logD 3.0

hERG 7uM

NN

OF3C

ON

N

NN

S

OO

F

pEC50 8.1 (84%)

logD 3.4

hERG >33uM

pEC50 7.6 (100%)

logD 2.9

hERG >33uM

SO O

NN

OF3C

ON

N

NN

F

pEC50 8.4 (89%)

logD 3.6

hERG 4uM

ON

NF3C

ON

N

NN

S

OO

F

CH2 spacer to polar sulphone

removes hERG liability

(potency and logD neutral)

Oxadiazole isomer

raises logD (increases

potency & hERG)

Combination gives

good potency & hERG







Further results from Brain Slice Assay

NO

NON

N

N

N

N

N

NN

OON

N

N

N

N

N

F3C

+ve Brain slice

logD 3.3

+ve Brain slice

logD 2.7

NO

NON

N

N

N

N

N

F3C

+ve Brain slice

logD 4.0

Matched Pairs

S

OO

NN

OON

N

NN

F3C

F

-ve Brain slice

logD 3.0

• CH2sulphone also clean in brain slice assay

O

OON

N

NN

SO O

F

O

CF3

-ve Brain slice

logD 2.9

NN

OON

N

NN

F3C

SO O

F

-ve Brain slice

logD 2.9

SO O

ON

NF3C

ON

N

NN

F

-ve Brain slice

logD 3.4

Sol 1.8 uM


Sol 1.8 mM [c]

logD 3.4

• End to end interaction is absent

• Ladder interactions observed

(Both a-CH interacting with O)

Understanding the solubility of the CH2 sulphone

SO O

ON

NF3C

ON

N

NN

F

SO O

O

F

ON

NF3C

N

N

NN H

H

SO O

O

F

ON

NF3C

N

N

NN H

H


Overall Profile looks good

SO O

ON

NF3C

ON

N

NN

F

Good Suspension PK (m,r,d) with dose linearity On-target, glucose lowering & GLP-1 release

Hu pEC50 8.1 (84%)

Mu pEC50 7.2 (71%)

logD 3.4

LLE 4.7

Clean in Brain Slice assay

-8

-6

-4

-2

0

2

0 10 20 30 40 50

vo

lta

ge

(m

V)

time (ms)

0.1% DMSO

1 µM AZ13457680

3 µM AZ13457680

10 µM AZ13457680

30 µM AZ13457680

100 µM 4-AP80

90

100

110

120

130

140

0.1 1 10 100

PS

l are

a (

% v

eh

icle

)

[AZ13457680] μM

hERG >33uM

Sol 1.8 uM


Synthesis – Oxadiazole isomers from N-CN

N N

N

N

ORNO

NX

N N

N

N

ORN

NH N

N

N

OR

N N

N

N

ORON

NX

N N

N

N

ORNN

OX

i) NaN3, Et3N.HCl, toluene, D;

ii) (iPr)2NEt, (XCO)2O,

Chlorobenzene, D

CNBr, NaHCO3,

CH2Cl2/H2O, 59%

i) NH2OH.HCl, Na2CO3, DMF;

ii) (XCO)2O, pyridine, toluene, D

i) XC(=NOH)NH2, ZnCl2,

THF/EtOAc;

ii) HCl, EtOH, D

• All 3 isomers available from common building block

• Chemistry works on phenol (R=H) or with protection (R=Bn)


Synthesis II

ON

N

CF3

CF3

N

ON

NN N

N

N

BrCF

3

OH

F

SO

O

O

O

ON

NN N

CF3

O

O

NH NO

O

N NN

N

N

BrCl

ON

NN N

N

N

OCF

3

SO O

F

ON

NN NH

CF3

ON

NN N

N

N

OHCF

3

F

SO

O

O

MeOF

BrO

MeO

F

O

MeO

F

O

OH

• CH2SO2Me building block introduced as last step

• NaSO2Me displacement of bromo avoids need for S-oxidation

• Pd catalysed Br to OH conversion works in presence of heterocycle

Convergent synthesis of 10 steps.

Longest linear sequence 6 steps

Run on >100g scale


Summary ON

N

NN

O

O S

OO

pEC50 7.2 (83%)

Sol 0.03 mM [c]

logD 3.2

hERG >33 mM

NO

NON

N

N

N

N

N

pEC50 8.1 (199%)

Sol 7uM

logD 3.3

LLE 4.8

NN

OON

N

N

N

N

N

F3C

pEC50 7.6 (220%)

Sol 120 mM

logD 2.7

LLE 4.9

pEC50 7.6 (121%)

Sol 1uM

logD 3.0

hERG 7uM

NN

OF3C

ON

N

NN

S

OO

F

SO O

ON

NF3C

ON

N

NN

F

pEC50 8.1 (84%)

Sol 1.8uM

logD 3.4

hERG >33 mM


Conclusions & Learning

Oxadiazoles - Not all bio-isosteres are equal!

- Subtle changes have big impact

Startpoint - Biggest difference to where you end up!

- Potency lead

- Solubility lead

confidence that contradiction

could be resolved

LLE - pEC50-logD

- good guide to progress (cpd quality)

- keeps phys props at the forefront

- Use with caution (agonists)

‘CH2’ - a small group makes a big difference

- solved hERG

X-ray structures - Can really assist design teams

- “Beauty is truth, truth beauty”


Acknowledgements Lead Generation (Mö)

Anders Broo

Öjvind Davidsson

Udo Bauer

Linda Sundström

Birgitta Svalstedt Karlsson

Walter Lindberg

Ann-Charlotte Egnell

Chemistry

Roger Butlin

Jamie Scott

Paul Schofield

David Clarke

Jules Hudson

Sam Groombridge

Kristen Goldberg

Alan Birch

Ruth Poultney

Sue Bowker

Phys / Comp Chem

Andrew Leach

Matt Wood

Phil MacFaul

DMPK

Charles O’Donnell

Hayley Brown

Pablo Morentin Gutierrez

Teresa Collins

Pharmaceutical Development

Claire Patterson

Project Leader

Darren McKerrecher

Legal

Tom Miller

Large Scale Chemistry

Neil Hawkins

David Rudge

Pete McLachlan

Informatics

Jasen Chooramun

Statistics

Liz Mills

Bioscience

Katy Brocklehurst

Carina Ämmälä

Joanne Teague

David Laber

David Baker

Rob Garcia

Simon Poucher

Steve Bloor

Animal Science & Welfare

Bill Brown

Neil Reavey

Diane Tibbs

Ruth Storer

Adrienne Sanders

Paul Sheridan

Lisa Shawcross

John Burton

Gary Slade

Laura Hayward

X-Ray

Per Svensson

Anne Ertan

discovery & optimisation of novel agonists of gpr119discovery & optimisation of novel...

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