Chemistry Agent

Expert agent for molecular operations, SMILES handling, and cheminformatics tasks.

Table of Contents

Overview

The Chemistry Agent specializes in molecular informatics operations. It handles SMILES notation, molecular property calculations, functional group identification, and chemical nomenclature conversions.

Expertise Areas

  • SMILES notation and molecular representations
  • Molecular similarity and structure analysis
  • Functional group identification
  • Chemical nomenclature (IUPAC, common names)
  • Molecular properties (molecular weight, formula)
  • Structure visualization

MCP Server

The Chemistry Agent connects to the OHMind-Chem MCP server for tool access.

Capabilities

Capability Description
SMILES Validation Check and canonicalize SMILES strings
Name Conversion Convert between IUPAC names, common names, and SMILES
Property Calculation Compute molecular weight, formula, atom counts
Similarity Analysis Calculate Tanimoto similarity between molecules
Functional Groups Identify functional groups in molecules
Structure Visualization Generate 2D structure images
Molecule Captioning Generate natural language descriptions

Available Tools

MoleculeWeight

Compute exact molecular weight from a SMILES string.

Parameters:

  • smiles (str): Input SMILES string

Returns: Molecular weight in g/mol

Example:

# Input: "CC(=O)OC1=CC=CC=C1C(=O)O"
# Output: 180.16 g/mol (Aspirin)

MoleculeAtomCount

Count atoms of each element in a molecule.

Parameters:

  • smiles (str): Input SMILES string

Returns: Dictionary of element counts

MoleculeSimilarity

Calculate Tanimoto similarity between two molecules.

Parameters:

  • smiles1 (str): First molecule SMILES
  • smiles2 (str): Second molecule SMILES

Returns: Similarity score (0-1) and qualitative description

FunctionalGroups

Detect common functional groups from SMILES.

Parameters:

  • smiles (str): Input SMILES string

Returns: List of identified functional groups (alcohol, amide, sulfonate, etc.)

SmilesCanonicalization

Canonicalize a SMILES string.

Parameters:

  • smiles (str): Input SMILES string
  • isomeric (bool): Include stereochemistry information
  • atom_maps (bool): Preserve atom mapping

Returns: Canonical SMILES string

MoleculeSmilesCheck

Validate a molecular SMILES string and explain syntax issues.

Parameters:

  • smiles (str): Input SMILES string

Returns: Validation result with error details if invalid

ReactionSmilesCheck

Validate reaction SMILES (reactants>reagents>products).

Parameters:

  • reaction_smiles (str): Reaction SMILES string

Returns: Validation result

Iupac2Smiles

Convert IUPAC name to SMILES (via PubChem).

Parameters:

  • iupac_name (str): IUPAC chemical name

Returns: SMILES string

Smiles2Iupac

Convert SMILES to IUPAC name.

Parameters:

  • smiles (str): Input SMILES string

Returns: IUPAC name

Smiles2Formula

Get molecular formula from SMILES.

Parameters:

  • smiles (str): Input SMILES string

Returns: Molecular formula (e.g., C9H8O4)

Name2Smiles

Convert common/brand/chemical name to SMILES.

Parameters:

  • name (str): Chemical name

Returns: SMILES string

Selfies2Smiles

Convert SELFIES to SMILES.

Parameters:

  • selfies (str): SELFIES string

Returns: SMILES string

Smiles2Selfies

Convert SMILES to SELFIES.

Parameters:

  • smiles (str): Input SMILES string

Returns: SELFIES string

Smiles2Cas

Look up approximate CAS number from SMILES (via PubChem).

Parameters:

  • smiles (str): Input SMILES string

Returns: CAS registry number

Smiles2Image

Render a 2D structure image from SMILES.

Parameters:

  • smiles (str): Input SMILES string
  • width (int): Image width in pixels
  • height (int): Image height in pixels

Returns: Path to generated image file

WebSearch

Chemistry-aware web/RAG search (Tavily-backed).

Parameters:

  • query (str): Search query

Returns: Search results with relevant chemistry information

MoleculeCaptioner

Generate natural-language caption/description of a molecule (MolT5 model).

Parameters:

  • smiles (str): Input SMILES string

Returns: Natural language description of the molecule

Example Prompts

Property and Functional Group Analysis

Using your OHMind-Chem MCP tools, analyze this molecule with SMILES 
`CC(=O)OC1=CC=CC=C1C(=O)O`.

1) Check that the SMILES is valid.
2) Report its molecular weight and formula.
3) List the functional groups and briefly explain what each group 
   typically does chemically.

Name to SMILES to Image Workflow

With your OHMind-Chem tools, convert the IUPAC name "2-propanol" to SMILES, 
verify the SMILES is valid, and then generate a small 300×300 structure image.

Return the SMILES, a short caption describing the molecule, and a link or 
reference to the generated image file.

Similarity and RAG-Assisted Design

Use your Chem MCP tools to compare lidocaine and procaine by SMILES.

1) Compute their structural similarity.
2) Use your web-search tool to summarize key differences in their 
   pharmacological profiles.
3) Propose a new candidate local anesthetic scaffold and justify it.

Molecular Weight Calculation

What is the molecular weight of the compound with SMILES CN+(C)C1=CC=CC=C1?

SMILES Validation

Check if this SMILES is valid: CC(C)(C)c1ccc(cc1)C(O)c2ccccc2
If valid, provide the canonical form.

Configuration

Environment Variables

Variable Purpose Default
TAVILY_API_KEY API key for web search Required for WebSearch
RDKIT_QUIET Suppress RDKit warnings 1

Tool Iteration

The Chemistry Agent supports iterative tool calling (up to 3 iterations) to handle complex queries that require multiple tool invocations.

Fallback Response

If the LLM returns an empty response after tool execution, the agent generates a formatted response from the collected tool results:

# Fallback formatting
if 'cal_molecular_weight' in collected_tool_results:
    result_parts.append(f"**Molecular Weight:** {mw_result}")
if 'identify_functional_groups' in collected_tool_results:
    result_parts.append(f"**Functional Groups:** {fg_result}")

See Also


Last updated: 2025-12-22 | OHMind v1.0.0


PolyAI Team
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