Amino acids with two chiral
centres were named in the past by allotting a name to the first diastereoisomer to
be discovered. The second diastereoisomer, when found or synthesized, was then assigned
the same name but with the prefix allo-. This method can be used only with trivial
names but not with semisystematic or systematic names. It is now recommended that
allo should be used only for alloisoleucine and allothreonine.
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. https://doi.org/10.1351/goldbook