Know which enantiomer to test first.

ChiralCall predicts the favored eutomer from a SMILES string — a validated decision-support layer for chiral prioritization. 81.61% accuracy across 3,655 compounds with published eutomer data in 977 compound classes including kinase atropisomers and agrochemicals.

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Your SMILES never stored. Processed in memory only. No third-party AI/LLM APIs.

3,655

verified compounds from published literature

81.61%

accuracy (Wilson 95% CI: 80.3%–82.8%)

977

compound classes

Verified against 100% of compounds with published enantiomer activity data. Tier 1, Tier 2, and Tier 3 compound classes covering agrochemicals, oncology, and emerging areas.

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For CRO teams

Run a blinded benchmark on your own compounds.

Submit up to 150 chiral compounds where you already know the active enantiomer. Compare ChiralCall's predictions against your ground truth — your answers never leave your machine. Free for 60 days.

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The cost of testing both

What does “just test both enantiomers” actually cost?

Every chiral resolution costs $5,000–$15,000 in synthesis, separation, and assay time. ChiralCall tells you which enantiomer to prioritize — before you spend a dollar on the wrong one.

Chiral compounds per quarter

1050500

Cost per chiral resolution

$5K$8,000$15K

Correct first calls / quarter

50/50

at 99% accuracy

Saved per quarter

$400K

by skipping the wrong enantiomer first

Annual savings

$1.6M

across 4 quarters

Researcher-weeks saved / quarter

150

~3 weeks per skipped resolution

Researcher-weeks saved / year

600

12 FTE-years of lab time redirected

Assumes ChiralCall correctly prioritizes the active enantiomer, avoiding one unnecessary resolution per correct call. Time estimate assumes ~3 weeks per chiral resolution (synthesis, separation, assay). Actual savings depend on your workflow, resolution method, and team size.

Famous drugs ChiralCall correctly predicts — blind.

Leave-one-out cross-validation on ChEMBL 36. Each compound excluded from direction vote during validation.

S-Ibuprofen

NSAIDs

CC(C)Cc1ccc(cc1)[C@@H](C)C(=O)O

Predict this compound →

S-Naproxen

NSAIDs

COc1ccc2cc([C@@H](C)C(=O)O)ccc2c1

Predict this compound →

S-Amlodipine

CCBs

CCOC(=O)C1=C(COCCN)NC(C)=C([C@@H]1c1ccccc1Cl)C(=O)OC

Predict this compound →

S-Lisinopril

ACE inhibitors

NCCCC[C@H](N[C@@H](CCc1ccccc1)C(=O)O)C(=O)N1CCC[C@H]1C(=O)O

Predict this compound →

Esomeprazole

PPIs

COc1ccc2[nH]c([S@@](=O)Cc3ncc(C)c(OC)c3C)nc2c1

Predict this compound →

Adagrasib

Kinase inhibitors

CN1CCN(c2cccc(-c3cnn4ccc(C5(C#N)CC(F)(F)C5)nc34)c2F)CC1

Predict this compound →

Propranolol

β-Blockers

CC(C)NC[C@H](O)COc1cccc2ccccc12

Predict this compound →

Amisulpride

Antipsychotics

CCN1CCC[C@@H]1CNC(=O)c1cc(S(N)(=O)=O)ccc1OC

Predict this compound →

Levetiracetam

Anticonvulsants

CC[C@@H](C(=O)N)N1CCCC1=O

Predict this compound →

Morphine

Opioids

CN1CC[C@]23c4c5ccc(O)c4O[C@H]2[C@@H](O)C=C[C@H]3[C@H]1C5

Predict this compound →

Naltrexone

Opioids

C(C1CC1)N1CC[C@@]23c4c5ccc(O)c4O[C@H]2[C@@]3(O)CCC(=O)[C@H]1C5

Predict this compound →

Albuterol

β-Agonists

CC(C)(C)NCC(COc1ccc(cc1)C(C)C)O

Predict this compound →

We publish our wrong predictions.

672 out of 3,655+ validated compounds predicted incorrectly. Every wrong prediction is disclosed with a structural explanation. This is how we earn trust.

3,655+

Verified compounds from published literature

81.61%

Validated accuracy across 977 compound classes

672

Wrong predictions — each one explained →

672 wrong predictions explained →Full methodology →

Wilson 95% CI: 80.3%–82.8% · Tier 1, Tier 2, and Tier 3 compound classes ·3,655 verified compounds from published active enantiomer data

The only tool that predicts kinase inhibitor chirality blind.

Axial atropisomers and point-chiral kinase inhibitors — all Tier 1, all 100% accuracy. From 2D SMILES alone.

Axial atropisomers — 21/21 = 100%

Adagrasib

Belvarafenib

BMS-986142

Zanubrutinib

Tirabrutinib

BINAP

BINOL

Gossypol

Point-chiral kinase compound classes — all Tier 1

PI3K inhibitors

100%

N=16 compounds

Idelalisib, copanlisib

JAK inhibitors

100%

N=24 compounds

Tofacitinib, ruxolitinib, baricitinib

ALK inhibitors

100%

N=11 compounds

Crizotinib, ceritinib, alectinib

PARP inhibitors

100%

N=16 compounds

Olaparib, niraparib

How axial chirality prediction works →

Will it work on my compound?

ChiralCall covers 977 compound classes across pharmaceuticals and agrochemicals. Compounds outside all classes return an explicit out-of-scope response.

Showing 53 of 53 compound classes

Arylpropionic acid NSAIDs

100%

N=44 compoundsTier 1

Ibuprofen, naproxen, ketoprofen, flurbiprofen, carprofen, fenoprofen

Aryl-ethanolamine β-agonists

98.7%

N=77 compoundsTier 1

Salbutamol, terbutaline, formoterol, salmeterol, levalbuterol

Aryloxy-propanolamine β-blockers

100%

N=83 compoundsTier 1

Propranolol, metoprolol, atenolol, timolol, nadolol

Amino-alcohol (modular)

95.4%

N=195 compoundsTier 1

Diverse amino-alcohol scaffolds — consolidated modular class

Morphinan opioid agonists

100%

N=18 compoundsTier 1

Morphine, codeine, oxycodone, hydromorphone, buprenorphine

Morphinan opioid antagonists

100%

N=69 compoundsTier 1

Naloxone, naltrexone, nalmefene, nalorphine

DHP CCB (C4 ring-chiral)

100%

N=18 compoundsTier 1

Amlodipine, felodipine, isradipine, nisoldipine (C4 stereocenter)

DHP CCB (ester side chain)

100%

N=16 compoundsTier 1

Benidipine, manidipine, barnidipine (ester side chain chiral)

DHP CCB (C4 symmetric-ester)

100%

N=3 compoundsTier 3

Isradipine, nimodipine, nitrendipine (symmetric esters, R-active)

Limited validation (N=3) — fewer than 6 compounds verified

Benzamide antipsychotics

100%

N=70 compoundsTier 1

Amisulpride, sulpiride, tiapride, raclopride

Catecholamine (3,4-diol)

92.9%

N=84 compoundsTier 1

Dihydrobenzofuran / chroman catechol aminoalcohols

Catecholamine amino acid

100%

N=6 compoundsTier 2

Levodopa, methyldopa, droxidopa (amino acid catecholamines)

Pyrrolidinone SV2A ligands

100%

N=25 compoundsTier 1

Levetiracetam, brivaracetam, α-ethyl/propyl/isobutyl analogues

8-Aminoquinoline antimalarials

100%

N=20 compoundsTier 1

Primaquine, tafenoquine (5-unsubstituted)

ACE inhibitors

100%

N=25 compoundsTier 1

Captopril, enalapril, lisinopril, ramipril, benazepril, quinapril, fosinopril

Proton pump inhibitors

100%

N=17 compoundsTier 1

Omeprazole, esomeprazole, pantoprazole, lansoprazole, rabeprazole

Axial biaryl atropisomers

100%

N=21 compoundsTier 1

BINAP/BINOL/gossypol + belvarafenib, adagrasib, zanubrutinib

Tert-carbinol triazole antifungals

98.6%

N=73 compoundsTier 1

Voriconazole, posaconazole, itraconazole — multi-stereocenter

Coumarin anticoagulants

100%

N=16 compoundsTier 1

Warfarin, acenocoumarol, phenprocoumon

Pyrimidine nucleoside analogs

100%

N=18 compoundsTier 1

Sofosbuvir, capecitabine, gemcitabine (uracil/thymine class)

Classical 4-AQ antimalarials

100%

N=49 compoundsTier 1

Chloroquine, hydroxychloroquine aminopropyl class

JAK inhibitors

100%

N=24 compoundsTier 1

Pyrrolo[2,3-d]pyrimidine JAK inhibitors (R-active)

SNRI antidepressants

100%

N=19 compoundsTier 1

Duloxetine, venlafaxine, desvenlafaxine

Propylamine antihistamines

100%

N=16 compoundsTier 1

Cetirizine, chlorphenamine, brompheniramine class

Cyclic-amine antihistamines

100%

N=11 compoundsTier 2

Levocetirizine, piperazine/piperidine antihistamines

PARP inhibitors

100%

N=16 compoundsTier 1

Chiral amine PARP inhibitors (olaparib, niraparib class)

ACCase herbicides

100%

N=17 compoundsTier 1Agro

Fluazifop-P, quizalofop-P, haloxyfop, mecoprop-P, dichlorprop-P

Amino acid sulfoxides

100%

N=8 compoundsTier 2

Methionine-class sulfoxides

Pipecoloxylidide anesthetics (N≥C3)

100%

N=10 compoundsTier 2

Bupivacaine, ropivacaine, levobupivacaine

PI3K inhibitors

100%

N=16 compoundsTier 1

Purine/pyrazolopyrimidine PI3K inhibitors (S-active)

Cephalosporin antibiotics

100%

N=10 compoundsTier 2

β-Lactam cephalosporins (6R,7R-active)

Carbapenem antibiotics

100%

N=8 compoundsTier 2

β-Lactam carbapenems (5R,6S-active)

Arylcyclohexylamine dissociatives

100%

N=11 compoundsTier 2

Ketamine, PCP, esketamine class

ALK inhibitors

100%

N=11 compoundsTier 2

Chiral amine ALK inhibitors (crizotinib class)

Oxazolidinone antibiotics

100%

N=10 compoundsTier 2

Linezolid, tedizolid (C5-chiral oxazolidinones)

Fluoroquinolone antibiotics

100%

N=8 compoundsTier 2

Levofloxacin, moxifloxacin (chiral quinolones)

3-OH benzodiazepines

100%

N=6 compoundsTier 2

Oxazepam, lorazepam, temazepam (3-hydroxy-1,4-benzodiazepine)

Pyrethroid insecticides

100%

N=9 compoundsTier 2Agro

Permethrin, cypermethrin, deltamethrin (cyclopropane 1R-active)

Triazole fungicides (open-chain)

100%

N=7 compoundsTier 2Agro

Open-chain carbinol triazole fungicides

Triazole fungicides (dioxolane)

100%

N=7 compoundsTier 2Agro

1,3-Dioxolane-core triazole fungicides

Triazole fungicides (fused ring)

100%

N=6 compoundsTier 2Agro

Fused ring / epoxide triazole fungicides

α-Carbon triazole fungicides

100%

N=6 compoundsTier 2Agro

α-Carbon triazole fungicides

Thienopyridine antiplatelets

100%

N=3 compoundsTier 3

Clopidogrel, prasugrel class

Limited validation (N=3) — fewer than 6 compounds verified

Benzothiazepine CCBs

100%

N=2 compoundsTier 3

Diltiazem class 1,5-benzothiazepine calcium channel blockers

Limited validation (N=2) — fewer than 6 compounds verified

Pipecoloxylidide (N-methyl)

N=1 compoundsTier 3

Mepivacaine sub-class (N-methyl pipecoloxylidides)

Only 1 compound tested, 0% accuracy — insufficient data

Non-classical 4-AQ

N/A

N=0 compoundsTier 3

Non-classical 4-aminoquinoline research compounds

No validated compounds yet — scaffold coverage only

Methoxyacetyl acylalanine fungicides

100%

N=4 compoundsTier 3Agro

Metalaxyl class acylalanine fungicides