Synthesis

Below is the peptide synthesis of capreomycin IA and IB. This was taken directly from the literature¹⁰.

No chemical synthesis of capreomycin could be found in any of the literature references. However, below is a synthesis devised from the peptide synthesis shown above. This is colour coded depending on the various amino residues. Each of the amino groups is added to the molecule in sequence linked by a peptide bond to eventually form the cyclo-structure. This was designed with some help from general references^1,2,3.

This synthesis would be identical for capreomycin IB other than the Serine-Bzl is replaced by Alanine and the synthesis works in exactly the same way.

The individual components of the capreomycin were colour coded as follows:

Red	DEA / UDA	b, b – diethoxyalanine / b - ureidodehydroalanine
Green	A₂pr	a, b – diaminopropionic acid
Turquoise	Ser	Serine
Blue	Cpd	Capreomycidine
Pink	b-Lys	b-Lysine

The black components of the synthesis were the various protecting groups involved:

Boc

tert – butoxycarbonyl

Z

Benzyloxycarbonyl

ONSu

N-hydroxysuccinimide

Nps

o-Nitrophenylsulphenyl

NO₂

Nitro

NO₂

Bzl

Benzene

Abbreviation Chemical Name

NMM

N-Methylmorpholine

DCC

N,N’-Dicyclohexylcarbodiimine

HOBt

l-Hydroxybenztriazole

HONSu

N-Hydroxysuccinimide

THF

Tetrahydrofuran

This is the synthesis of capreomycin IA. The IB form is produced in an identical fashion except that Ser – Bzl , is replaced with Ala.

The structure difference between these two forms is shown on the Structure page.

Boc	tert – butoxycarbonyl
Z	Benzyloxycarbonyl
ONSu	N-hydroxysuccinimide
Nps	o-Nitrophenylsulphenyl
NO₂	Nitro	NO₂
Bzl	Benzene

Abbreviation	Chemical Name
NMM	N-Methylmorpholine
DCC	N,N’-Dicyclohexylcarbodiimine
HOBt	l-Hydroxybenztriazole
HONSu	N-Hydroxysuccinimide
THF	Tetrahydrofuran