Global Chemical Database

Molecular Building Blocks

This topic covers important starting materials, intermediates, and molecular building blocks used in organic synthesis, medicinal chemistry, and materials chemistry.

1,3-Dimethylurea

What does a 3-carbon molecule have to do with caffeine—and a modern electrochemical reaction inspired by batteries?

4-Methoxybenzylchloride

How do chemists tell one protected alcohol: —Your turn.— while telling another:

3,5-Difluoropyridine-2-carboxylic acid

Fluorine forms one of the strongest bonds to carbon. So once F is attached to an aromatic ring, it must be difficult to replace... right?

3,5-Dimethoxybenzaldehyde

Why would chemists hide two hydroxyl groups before building a natural product?

Ethyl N-(diphenylmethylene)glycinate

Why would chemists turn tiny glycine into a molecule carrying two large phenyl rings?

Methylurea

ow much difference can one methyl group make? Start with urea:

5-Bromo-3-nitropyridine-2-carbonitrile

Which group would you expect fluoride to replace? Look at 5-bromo-3-nitropyridine-2-carbonitrile.

4-Benzyloxyaniline hydrochloride

Why would a chemist deliberately add an entire benzyl group to a molecule...

4-Pyridazinecarboxylic acid

How can a molecule with only five carbons become useful in drug discovery?

4-Methyl-1,3-benzenediol

How much difference can one carbon make? Resorcinol has two hydroxyl groups on a benzene ring.

6-Chlorouracil

What happens if you take one of RNA's familiar molecular building blocks...

N-(Trifluoroacetyl)glycine

Sometimes the most useful thing a chemist can tell part of a molecule is:

Cyclobutanecarboxylic acid

What's the difference between a triangle and a folded square?

3-Amino-2-ethoxycarbonylpyrrole hydrochloride

Can a tiny molecule already contain the blueprint for a ring that doesn't exist yet?

Cyclopropyl carbinol

How much chemistry can hide inside four carbon atoms? Quite a lot.

4-Bromo-1H-imidazole

What do the proteins in your body and a bottle of laboratory reagent have in common?

Methyl (Z)-3-aminocrotonate

How does a straight-chain molecule turn into a nitrogen ring?

7-Bromo-1,2,3,4-tetrahydroisoquinoline

How do medicinal chemists explore thousands of possible molecules without starting from scratch every time?

(Bromomethyl)cyclobutane

Can changing one tiny side group change how an entire drug molecule behaves?

Cyclopropanecarboxaldehyde

What's the smallest carbon ring you can build? Three carbon atoms.

2,5-Dibromofluorobenzene

Two bromine atoms. Same molecule. Same element. So surely a chemist can't tell them apart?

2-Bromo-5-chlorophenol

Bromine and chlorine sit next to the same benzene ring. Surely they're basically doing the same job?

trans-1,2-Cyclobutanedicarboxylic acid

Can two molecules contain exactly the same atoms, connected in exactly the same order—and still be different chemicals?

5-Bromo-2-fluorophenol

What can a chemist do with one tiny benzene ring? Quite a lot—if the right pieces are attached to it.

Methyl 4-bromocrotonate

How much chemistry can you pack into five carbon atoms? Quite a lot.

2-Amino-5-bromo-4-chloropyridine

Can a molecule have more than one "door" for chemists to open?

3-Methoxy-5-methyl-2-pyrazinamine

How do scientists discover a better drug molecule? Often, they don't make one giant leap.

2,6-Dichloro-3,5-dimethoxyphenyl isocyanate

A chemical with a name this long probably doesn't sound like it has a story.

cis-3,5-Diacetoxy-1-cyclopentene

Can an enzyme tell the difference between two parts of a molecule that look identical?

Piperazine-2,6-dione hydrochloride

Can a molecule be important even if it never becomes a medicine?

(2-Cyano-4-(methoxycarbonyl)phenyl)boronic acid pinacol ester

Most chemicals never become famous. Some are born to become parts of something else.

5'-O-(4,4'-Dimethoxytrityl)-N4-benzoyl-2'-deoxycytidine-3'-(2-cyanoethyl-N,N-diisopropyl)phosphoramidite

How do scientists make DNA? Not by growing it. By building it—one letter at a time.

1,2,4-Triazol-5-one

Some of the most important molecules in medicine are astonishingly small.

3,4,5-Trimethoxybenzaldehyde

Why do so many drug molecules begin with the same aromatic ring?

(S)-(+)-2,2-Dimethyl-1,3-dioxolane-4-methanol

Imagine trying to repaint a house without getting any paint on the windows.

Cyclopropylboronic acid

Why are medicinal chemists so fascinated by triangles? Not geometric triangles—but molecular ones.

2-Fluoro-5-nitrotoluene

Why do chemists put fluorine into so many modern medicines? The answer isn't simply "because fluorine is reactive." In fact, the opposite is often true. Why do chemists put fluorine into so many modern medicines? The answer isn't simply "because fluorine is reactive." In fact, the opposite is often true.

2-Butyl-2-ethyloxirane

Three atoms. That's all it takes to change the way chemists build molecules.