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ForwardSynthesis (do_forward_synthesis)

Reaction Reaction Prediction Neural Networks APIs SMILES
Table of Contents
Version: 0.1.0 Last Update: 2025/06/05 MCP Support Python Calling Support
Given reactants and reagents, predict the product(s) of a chemical reaction.

Example

Input:

reactants_and_reagents_smiles: 'CCN.CN1C=CC=C1C=O'

Text Input (used for the run_text function in the Python calling mode):

reactants_and_reagents_smiles: 'CCN.CN1C=CC=C1C=O'

Output:

'CCNCc1cccn1C'

Usage

The tool supports both MCP mode and Python calling mode.

Environment Variables

This tool requires the following environment variables:

  • RXN4CHEM_API_KEY: The API key for IBM RXN4Chem.

MCP Mode

Configure your MCP client following its instructions with something like:

{
    "command": "/ABSTRACT/PATH/TO/uv",  // Use `which uv` to get its path
    "args": ["--directory", "/ABSTRACT/PATH/TO/ChemMCP", "run", "--tools", "ForwardSynthesis"],
    "toolCallTimeoutMillis": 300000,
    "env": {
        "RXN4CHEM_API_KEY": "VALUE_TO_BE_SET"
    }
}

Python Calling Mode

import os
from chemmcp.tools import ForwardSynthesis

# Set the environment variables
os.environ['RXN4CHEM_API_KEY'] = 'VALUE_TO_BE_SET'

# Initialize the tool
tool = ForwardSynthesis()

# The tool has two alternative ways to run:
# 1. Run with separate input domains (recommended)
output = tool.run_code(
    reactants_and_reagents_smiles='CCN.CN1C=CC=C1C=O'
)
# 2. Run with text-only input
output = tool.run_text(
    reactants_and_reagents_smiles='CCN.CN1C=CC=C1C=O'
)

Each tool in ChemMCP has two ways to run:

  • run_code (recommended): The inputs contain one or more domains, each of which can be a str, an int, a float, etc.
  • run_text: The inputs are a single string in a specific format. The tool will parse the string to extract the input domains. This is useful in scenarios where an agent framework calls tools only with text input. The output is the same in both cases.

For the input and output domains, please refer to the tool’s signature.

Tool Signature

Input

Used in the MCP mode, as well as the run_code function in the Python calling mode.

NameTypeDefaultDescription
reactants_and_reagents_smilesstrN/AThe SMILES of the reactants and reagents separated by a dot ‘.’.

Text Input

Used in the run_text function in the Python calling mode.

NameTypeDefaultDescription
reactants_and_reagents_smilesstrN/AThe SMILES of the reactants and reagents separated by a dot ‘.’.

Output

The output is the same in both input cases.

NameTypeDescription
product_smilesstrThe SMILES of the product(s).

Envs

NameDescription
RXN4CHEM_API_KEYThe API key for IBM RXN4Chem.

Implementation Details

  • Implementation Description: Uses the IBM RXN for Chem API to predict the product(s) of a chemical reaction. Outputs the top 1 prediction.
  • Open-source dependencies (code source or required libraries):
  • Hosted services and software (required for running the tool):