Molecule challenge
Draw a drug-like molecule. Five simple rules decide your score. Hit all five for 100.
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Resets Monday 12 Oct. Signed-in players are ranked.
No designs yet this week. Be the first on the board.
How the score works
Each rule is worth up to 20 points. These are well-known rules of thumb that medicinal chemists use as a first filter, so a high score means "looks like a typical drug-like molecule", not "this will work as a drug".
- Size: molecular weight between 250 and 450.
- H-bond donors: N or O atoms carrying hydrogen, 3 or fewer.
- H-bond acceptors: N and O atoms, between 2 and 8.
- Flexibility: 7 or fewer rotatable bonds.
- Rings: between 2 and 4.