Amino aldehydes are a group of compounds that have both amino (-NH2) and aldehyde (-CHO) groups. During the last decade α-amino aldehydes have attracted widespread attention as the important natural source of chiral substrates useful in stereocontrolled organic synthesis. They are of special interest due to their ready availability in both enantiomeric forms from natural sources, as well as their pronounced versatility, due to the presence of both the formyl group and suitably protected amino functionality in the molecule.
However, there is no possibility for intramolecular stabilization in the case of α-amino aldehydes. Owing to the presence of incompatible functional groups, this class of compounds is unstable. The history of α-amino aldehydes can be traced back to Fischer's discovery of glucosamine in 1902, in which unprotected amine and aldehyde functionalities are stabilized as a cyclic hemiacetal.
These bifunctional compounds exhibit a valuable dual reactivity, which has been utilized in a broad range of synthetic applications.
Medicine: Some peptide derivatives containing α-amino aldehyde unit are potent inhibitors of proteases, such as papain, thrombin, trypsin, calpain, caspases and viral proteases, which can be applied range from antiviral drugs to anti-thrombotic, anti-cataract or anti-tumor agents.
Intermediates: Aldehyde group can be transformed into a wide range of structural frameworks. Therefore, α-amino aldehydes are among the most widely used intermediates in synthesis.
Leading compounds: The amino aldehydes are not only potential drug candidates, but also useful precursors of other compounds, such as diamines, amino alcohols, etc. The development of new derivatives, especially those with α-substituted β-amino aldehyde residues, could be useful to discover new drug leads.
Building blocks: The juxtaposition of amino and aldehyde functionalities predisposes chiral amino aldehydes as divergent building blocks within organic chemistry.