GenMol quickstart
Step-by-step guide to generating your first molecules with GenMol on the platform.
You want to generate novel drug-like molecules with GenMol; this walks you through your first run in five steps — select a mode, set the parameters, submit, and review the output. Start in de novo mode to see the full pipeline without needing any input molecules.
Quick molecule generation with .bloom* platform
GenMol uses NVIDIA's masked discrete diffusion model on SAFE molecular representations to generate novel drug-like molecules. This guide walks through your first generation run, from selecting a mode to interpreting the output molecules.
Step-by-step generation workflow
Access the GenMol tool
Navigate to GenMol in the .bloom* tool selector, or ask Ivy directly:
- "Generate 100 drug-like molecules with GenMol"
- "Run GenMol in de novo mode"
Select a generation mode
GenMol supports nine run modes. Choose the one that matches your workflow:
| Mode | When to use | Required input |
|---|---|---|
| de novo | Explore novel chemical space without constraints | None |
| lead optimization | Create analogs of a known hit | Seed SMILES + similarity threshold |
| scaffold decoration | Attach fragments to a core scaffold | Scaffold SMILES with attachment points |
| linker design | Connect two fragment hits | Two fragment SMILES |
| motif extension | Grow a pharmacophore motif into a full molecule | Motif SMILES |
| PMO | Optimize toward a scoring oracle | Oracle name (qed, gsk3b, etc.) |
| fragment constrained | Fix specific fragments, generate the rest | SAFE-encoded fixed fragments |
For your first run, start with de novo mode to see the full pipeline without needing input molecules.
Configure generation parameters
Basic settings (recommended for first run):
- Mode: de novo
- Number of molecules: 100 (good balance of speed and diversity)
- Quality filter: Enabled (filters out invalid and non-drug-like molecules)
- Job name: Enter a descriptive name or leave blank for auto-generation
Advanced settings (via gear icon):
- num_steps: Diffusion steps per molecule (default is fine for most runs)
- temperature: Controls diversity vs. quality tradeoff (default: 1.0; lower = more conservative, higher = more diverse)
- seed: Set for reproducible results
Submit and monitor the job
- Click Generate Molecules to start the job
- .bloom* shows real-time progress with live ETA
- Typical completion: 30 seconds to 2 minutes for 100 molecules
- Job status updates appear in the job panel and as notifications
Review and analyze results
Canvas visualization:
- A result card appears on the canvas showing a 2D molecule grid
- Each molecule displays its structure, QED score, and SA score
- Property histograms show the distribution of molecular weight, logP, and TPSA across all generated molecules
- SAFE fragment decomposition view shows how molecules break down into reusable fragments
Quality metrics panel:
- Validity rate: percentage of chemically valid molecules generated. Invalid ones are removed from the returned set unless you turn
enforce_validityoff - Uniqueness rate: percentage of unique (non-duplicate) molecules
- QED mean: average RDKit drug-likeness estimate across the set
- Diversity index: mean pairwise Tanimoto distance across the generated set
None of these is a measurement. They describe the structures, not any property anyone observed — see how GenMol results compare to the bench.
Download options:
- CSV: SMILES, SAFE notation, and all computed property scores
- SDF: 3D coordinates for downstream docking or visualization
- JSON: Full structured results with metadata
Common generation scenarios
De novo exploration
- Select "de novo" mode with 500-1,000 molecules
- Enable drug-likeness filter for a cleaner output set
- Sort results by QED or diversity score
- Pick top candidates for ADMET screening or docking
Lead optimization
- Enter the SMILES of your lead compound (e.g.,
CC(=O)Oc1ccccc1C(=O)Ofor aspirin) - Set similarity threshold to 0.6-0.8 (lower = more diverse analogs)
- Generate 200-500 analogs
- Compare analogs side-by-side in the canvas grid
- Feed top hits to ADMET-AI for property profiling
Scaffold decoration
- Enter your scaffold SMILES with SAFE attachment points
- Generate 100-300 decorated molecules
- Review the R-group variations in the molecule grid
- Export decorated scaffolds for retrosynthetic analysis with AiZynthFinder
Fragment linking
- Provide two fragment SMILES from your fragment screening campaign
- Generate 100-200 linked molecules
- Filter for drug-likeness and synthetic accessibility
- Dock top linkers against the target protein with DiffDock
Quality control checklist
Before submission
- Correct generation mode selected for your use case
- Seed SMILES is valid (check with PubChem or RDKit)
- Similarity threshold is reasonable (0.5-0.8 for lead optimization)
- Molecule count is appropriate (100 for quick exploration, 1,000+ for campaigns)
- Quality filters enabled if you want drug-like output
After generation
- Validity rate is >90% (if lower, check seed SMILES or constraints)
- Uniqueness rate is >80% (low uniqueness may indicate constrained generation)
- You have read the
quality_filtersblock to see how many molecules the filters removed - Generated molecules are structurally reasonable (spot-check 2D structures; this catches what no metric reports)
- Property distributions match your target profile
- You are treating the set as a hypothesis pool, not as candidates that have been shown to be makeable or active
Next steps after generation
Property screening:
- Run ADMET-AI or ADMETLab3 on generated molecules for absorption, distribution, metabolism, excretion, and toxicity predictions
- Use ProTox-3 for toxicity endpoint estimation
- Apply DeepChem for custom property prediction
Synthetic feasibility:
- Run AiZynthFinder on top candidates for retrosynthetic analysis — this is the only makeability check available here
- Check ZINC for purchasable building blocks
- Have a chemist read the structures before anything is ordered. Treat
sa_scoreas a within-series ranking hint, not a makeability verdict
Structural validation:
- Dock generated molecules against target proteins using DiffDock
- Minimize docked poses with MM-GBSA, which reports complex energies rather than a binding free energy
- Build a Compound Passport for comprehensive drug-likeness assessment
Iterative optimization:
- Use top-scoring molecules as seeds for a second round of lead optimization
- Extract promising fragments and use them as constraints for fragment-constrained generation
- Run PMO mode targeting specific property improvements
Read next
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How GenMol results compare to the bench
What a GenMol-generated molecule has been shown to agree with experimentally, and why every published figure is an in silico benchmark graded by an oracle.
GenMol troubleshooting
Fix GenMol invalid SMILES, low validity or diversity through temperature and num_steps — plus the known defect that min_qed and max_sa_score never apply.