Green chemistry in drug discovery emphasizes the design of synthetic routes that are safer, more sustainable, and environmentally responsible — without compromising efficiency or innovation. It’s about rethinking how we build molecules to reduce waste, energy use, and toxic byproducts.

1. Atom Economy & Step Economy

• Favor reactions where most atoms from starting materials end up in the final product.
• Minimize the number of synthetic steps to reduce waste, cost, and energy consumption.

2. Renewable Feedstocks

• Use bio-based starting materials (e.g., sugars, terpenes, amino acids) instead of petroleum-derived reagents.
• Explore biocatalysis and fermentation as greener routes to complex intermediates.

3. Catalysis Over Stoichiometric Reagents

• Prioritize catalytic reactions (metal, organocatalysts, enzymes) to reduce reagent excess
•  Emphasize recyclable catalysts and low-toxicity metals (e.g., iron, copper over palladium or platinum).

4. Safer Solvents and Solvent-Free Reactions

• Replace hazardous solvents (e.g., dichloromethane, DMF) with greener alternatives like ethanol, ethyl acetate, water, or supercritical CO₂.
• Highlight solvent-free or microwave-assisted reactions that reduce environmental footprint.

5. Energy Efficiency

• Favor reactions that proceed at ambient temperature and pressure
• Use microwave, photochemical, or electrochemical methods to reduce energy input.

6. Waste Minimization and Process Intensification

• Design reactions with minimal purification steps (e.g., telescoping reactions).
• Use flow chemistry to improve scalability, safety, and reduce solvent use

7. Lifecycle Thinking

• Consider the entire lifecycle of a synthetic route — from raw materials to end-of-life disposal.
• Incorporate Life Cycle Assessment (LCA) tools to evaluate environmental impact.