---
title: "Retrosynthesis Examples for Drug-Like Molecules with RENKIN"
description: "Suzuki coupling and amide bond disconnection examples on drug-like molecules using RENKIN's retrosynthesis engine."
---

# Drug-like Molecules

Examples of retrosynthesis on more complex, drug-like molecules.

## 4-Phenylpyridine (Suzuki coupling product)

SMILES: `c1ccc(-c2ccncc2)cc1`

This biaryl compound is typically synthesized via Suzuki-Miyaura cross-coupling.

RENKIN's graph-based `suzuki_retro` rule disconnects the biaryl bond into an
aryl bromide + an aryl-H fragment (`suzuki_retro` tracks only these two
organic fragments, not a boronic ester/acid as a separate species — the
missing boronate activation on the aryl-H side is implicit, not modeled):

```
c1ccc(-c2ccncc2)cc1
    → Brc1ccccc1 + c1ccccn1
    [suzuki_retro]
```

or

```
c1ccc(-c2ccncc2)cc1
    → Brc1ccncc1 + c1ccccc1
    [suzuki_retro]
```

Both bromobenzene (`Brc1ccccc1`) and pyridine (`c1ccccn1`) are in the default building block stock.

## 4-Fluorobiphenyl

SMILES: `Fc1ccc(-c2ccccc2)cc1`

RENKIN finds two Suzuki disconnection modes (again, aryl bromide + aryl-H —
see the note above about the implicit boronate side):

1. Fluorine-substituted arene as the bromide partner:
```
Fc1ccc(-c2ccccc2)cc1
    → Fc1ccc(Br)cc1 + c1ccccc1
```

2. Or the reverse:
```
Fc1ccc(-c2ccccc2)cc1
    → Brc1ccccc1 + Fc1ccccc1
```

## Paracetamol (Acetaminophen)

SMILES: `CC(=O)Nc1ccc(O)cc1`

Amide bond disconnection:

```
CC(=O)Nc1ccc(O)cc1
    → CC(=O)O + Nc1ccc(O)cc1
    [amide_cleavage]
```

- **Acetic acid** (`CC(=O)O`) — in stock
- **4-Aminophenol** (`Nc1ccc(O)cc1`) — in stock

## Try More Examples

[**→ Open Playground**](../playground/){ .md-button }

Paste any SMILES into the playground to explore retrosynthetic routes.
