An asymmetric formal synthesis of trichodermamides B and C was achieved in 15 steps based on a tyrosine ester chiral-pool approach. Key features of this synthesis include stereoselective construction of a cis -1,2-oxazadecaline core by an acid-mediated tandem deprotection-intramolecular oxy-Michael reaction, oxime ether formation via an N -bromination-elimination sequence, and diene construction by a palladium-catalyzed demonomethylcarbonation.