Peptide synthesis cheatsheetEvery protecting group of the course, how it is put on, how it is taken off and what it survives, plus the coupling reagent DCC and the Merrifield resin.

Group

Protects

Put on with

Taken off with

Boc, tert-butoxycarbonyl

the amine

Boc2O, Et3N

TFA, 25 °C, or H3O+: releases isobutene and CO2

Cbz (Z), benzyloxycarbonyl

the amine

benzyl chloroformate, NaOH

H2, Pd/C: releases toluene and CO2

OMe, methyl ester

the acid

SOCl2, MeOH

LiOH 1 N: releases methanol

OBn, benzyl ester

the acid

O-benzyl-N,N’-diisopropylisourea

H2, Pd/C: releases toluene

Draw the products and intermediates of a peptide synthesis, from protecting groups to DCC coupling, and follow two slide shows. The exercises need JavaScript, because every drawing is checked in your browser.

Why protect — heat two amino acids, and count what forms

Protecting groups — put them on, take them off

Coupling with DCC — activate the acid, then form the amide

Planning a synthesis — protect, couple, deprotect, in the right order

Builder — type a sequence, see the molecule

Cheatsheet — every group, how it goes on and comes off

Talks — two slide shows, mechanisms included

About — what the site is, and how to cite it

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