This book has emerged from courses that I taught to biochemistry students at the
undergraduate and graduate levels, to persons with a limited knowledge of organic
chemistry, to chemists with experience in other fields, and to peptide chemists. It
assumes that the reader possesses a minimum knowledge of organic and amino-acid
chemistry. It comprises 188 self-standing sections that include 207 figures written
in clear language, with limited use of abbreviations. The focus is on understanding
how and why reactions and phenomena occur. There are a few tables of illustrative
data, but no tables of compounds or reaction conditions. The material is presented
progressively, with some repetition, and then with amplification after the basics have
been dealt with. The fundamentals of peptide synthesis, with an emphasis on the
intermediates that are encountered in aminolysis reactions, are presented initially.
The coupling of Nα-protected amino acids and Nα-protected peptides and their
tendencies to isomerize are then addressed separately. This allows for easier comprehension
of the issues of stereomutation and the applicability of coupling reactions.
Protection of functional groups is introduced on the basis of the methods that are
employed for removal of the protectors. A chapter is devoted to the question of
stereomutation, which is now more complex, following the discovery that Nα-
protected amino acids can also give rise to oxazolones. Other chapters are devoted
to solid-phase synthesis, side-chain protection and side reactions, amplification on
coupling methods, and miscellaneous topics. Points to note are that esters that
undergo aminolysis are referred to as activated esters, which is why they react, and
not active esters, and that in two cases two abbreviations (Z and Cbz; HOObt and
HODhbt) are used haphazardly for one entity because that is the reality of the peptide
literature. An effort has been made to convey to the reader a notion of how the field
of peptide chemistry has developed. To this end, the references are located at the
end of each section and include the titles of articles. Most references have been
selected on the basis of the main theme that the chapter addresses. When the
relevance of a paper is not obvious from the title, a phrase has been inserted in
parentheses. The titles of papers written in German and French have been translated.
For obvious reasons the number of references had to be limited. I extend my
apologies to anyone who considers his or her work to have been unjustifiably omitted.
Some poetic license was exercised in the creation of the manuscript and the reaction
schemes. Inclusion of all details and exceptions to statements would have made the
whole too unruly.