Beginning of the year, we reported about Adamantyls as Chemist’s Best Friends and our portfolio of products containing this motif is constantly growing. The highly lipophilic, bulky adamantyl motif is a promising and validated building block used to increase the drug-qualitities of lead compounds without increasing their toxicity.

Herein, provide an update on the derivatives available and our synthetic improvements. We have developed a reliable and robust process for the synthesis of L- and D-Adamantylalanine, respectively. Our process involves an asymmetric transformation induced by crystallization. Thus, the amino acid is obtained in high chemical and optical purity and can subsequently be transformed to the protected derivative, e.g. Alloc, Boc, Cbz, Fmoc.

Adamantane is a polycyclic carbon cage and belongs to the group of diamondoids. The adamantyl moiety can be introduced into existing drugs to increase their lipophilicity, thus improving the membrane permeability of water-soluble drugs, or to improve their stability against enzymatic cleavage due to bulkiness and resulting sterically hindered access. Thus, the overall pharmacological performance can be enhanced. Furthermore, due to its hydrophobic bulk, the adamantyl moiety fits hydrophobic cavities. The first report on adamantane in medicinal chemistry displayed potent anti-Influenza A activity of (1-amino)adamantane. Overall, adamantyl-based compounds are reported for clinical use as anti-viral agents and for the treatment of medical conditions such as type 2 diabetes and neurological disorders. Furthermore, adamantane derivatives have shown in vitro activity against various coronaviruses.

➔ If you are unable to find your required adamantyl building block in our catalogue, inquire with our Custom Synthesis Service.

References:

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Adamantanes might be protective from COVID-19 in patients with neurological diseases: multiple sclerosis, parkinsonism and cognitive impairment; K. Rejdak, P. Grieb; Mult. Scler. Relat. Disord. 2020; 42: 102163. https://doi.org/10.1016/j.msard.2020.102163.

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