Good news!
"Ring-shaped chemical structures called saturated heterocycles are found in most FDA-approved drugs but are often difficult to create. ... Research chemists have just developed a surprisingly easy method for making many of these sought-after compounds from inexpensive starting chemicals.
The new method ... enables chemists to make saturated heterocycles from relatively simple, chain-like amine compounds. ...
The researchers demonstrated the power of their new method by using it to perform an efficient synthesis of stemoamide, a complex plant-derived compound found in traditional medicines. ..."
From the abstract:
"Recent developments of bifunctional ligands have rapidly advanced palladium-catalysed C(sp3)–H activation reactions directed by native carboxylic acids. However, using this approach in inter- or intramolecular C(sp3)–H amination reactions is often hampered by N-coordination overriding the directing effect of the native carboxyl group. Here we report the design and development of chlorinated pyridine–pyridone ligands, which can overcome N-coordination and enable exclusive carboxylic-acid-directed lactamization and cycloamination of N-protected ω-amino acids. The compartmentalization of directed C(sp3)–H activation and C(sp3)–N bond formation in this reaction is distinct from existing C(sp3)–H amination approaches, in which both processes are directed by nitrogen. The protocols described in this report transform linear ω-amino acids into valuable cyclic β-amino acids possessing γ- and δ-lactam, pyrrolidine and tetrahydroquinoline scaffolds pertinent to drug discovery. The utility of this process was demonstrated by the formal synthesis of stemoamide."
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