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Aspirin: Molecular Property Analysis

Small Molecule Chemistry RDKit
Calculate molecular properties of aspirin (acetylsalicylic acid) using RDKit chemistry tools. Analyze drug-likeness via Lipinski's Rule of Five, compute TPSA for membrane permeability, and convert to InChI for database searching. Aspirin: MW 180.16 g/mol, LogP 1.31, TPSA 63.60 Ų, 0/4 Lipinski violations - fully drug-like.

Chat Dialogs

Calculate molecular weight

PROMPT: What is the molecular weight of aspirin?
CONTEXT: Aspirin (acetylsalicylic acid) is one of the most widely used drugs. SMILES: CC(=O)Oc1ccccc1C(=O)O. CAS: 50-78-2.
THINKING: I'll use calculate_molecular_weight with the aspirin SMILES.
RESULT:

Molecular weight of CC(=O)Oc1ccccc1C(=O)O: 180.16 g/mol
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Get molecular formula

PROMPT: What is the molecular formula of aspirin?
THINKING: I'll use get_molecular_formula to derive the formula from SMILES.
RESULT:

Molecular formula of CC(=O)Oc1ccccc1C(=O)O: C₉H₈O₄
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Check Lipinski's Rule of Five

PROMPT: Is aspirin drug-like according to Lipinski's rules?
CONTEXT: Lipinski's Rule of Five predicts oral bioavailability based on: MW ≤500, LogP ≤5, H-bond donors ≤5, H-bond acceptors ≤10. Violations ≤1 indicates drug-likeness.
THINKING: I'll run check_lipinski_ro5 to evaluate all four criteria.
RESULT:

Lipinski Ro5 Analysis for Aspirin:

| Property | Value | Limit | Status |
|----------|-------|-------|--------|
| Molecular Weight | 180.16 | ≤500 | PASS |
| LogP | 1.31 | ≤5 | PASS |
| H-Bond Donors | 1 | ≤5 | PASS |
| H-Bond Acceptors | 3 | ≤10 | PASS |

Violations: 0/4 - Drug-like
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Calculate TPSA

PROMPT: What is the topological polar surface area of aspirin?
CONTEXT: TPSA is important for predicting membrane permeability. Drugs with TPSA < 140 Ų tend to have good oral absorption. TPSA < 90 Ų indicates CNS penetration.
THINKING: I'll use calculate_tpsa to compute the polar surface area.
RESULT:

TPSA of CC(=O)Oc1ccccc1C(=O)O: 63.60 Ų

Interpretation: TPSA < 90 Ų suggests good intestinal absorption and potential CNS penetration.
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Convert to InChI

PROMPT: Generate the InChI identifier for aspirin.
CONTEXT: InChI (International Chemical Identifier) is a machine-readable string that uniquely identifies chemical substances for database searching.
THINKING: I'll convert the SMILES to InChI using smiles_to_inchi.
RESULT:

InChI=1S/C9H8O4/c1-6(10)13-8-5-3-2-4-7(8)9(11)12/h2-5H,1H3,(H,11,12)
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Technical Details

Molecular Weight Calculation

TOOL: calculate_molecular_weight
{ "smiles": "CC(=O)Oc1ccccc1C(=O)O" }
OUTPUT:
Molecular weight of CC(=O)Oc1ccccc1C(=O)O: 180.16 g/mol

Molecular Formula

TOOL: get_molecular_formula
{ "smiles": "CC(=O)Oc1ccccc1C(=O)O" }
OUTPUT:
Molecular formula of CC(=O)Oc1ccccc1C(=O)O: C9H8O4

Lipinski Rule of Five

TOOL: check_lipinski_ro5
{ "smiles": "CC(=O)Oc1ccccc1C(=O)O" }
OUTPUT:
Lipinski Ro5 for CC(=O)Oc1ccccc1C(=O)O: ✓ MW: 180.16 (≤500) ✓ LogP: 1.31 (≤5) ✓ HBD: 1 (≤5) ✓ HBA: 3 (≤10) Violations: 0/4 - Drug-like ✓

Topological Polar Surface Area

TOOL: calculate_tpsa
{ "smiles": "CC(=O)Oc1ccccc1C(=O)O" }
OUTPUT:
TPSA of CC(=O)Oc1ccccc1C(=O)O: 63.60 Ų

InChI Conversion

TOOL: smiles_to_inchi
{ "smiles": "CC(=O)Oc1ccccc1C(=O)O" }
OUTPUT:
InChI: InChI=1S/C9H8O4/c1-6(10)13-8-5-3-2-4-7(8)9(11)12/h2-5H,1H3,(H,11,12)

Property Summary

Property Value
Molecule Aspirin (Acetylsalicylic acid)
SMILES CC(=O)Oc1ccccc1C(=O)O
Formula C₉H₈O₄
Molecular Weight 180.16 g/mol
LogP 1.31
TPSA 63.60 Ų
H-Bond Donors 1
H-Bond Acceptors 3
Lipinski Violations 0/4 - Drug-like

Tools Used

calculate_molecular_weight get_molecular_formula check_lipinski_ro5 calculate_tpsa smiles_to_inchi

Outcomes

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