The synthesis and transformations of 2-[2-ethoxycarbonyl-2-(2-pyridinyl)ethenyl]amino-3-dimethylaminopropenoates. The synthesis of substituted beta-amino-alpha,beta-didehydro-alpha-amino acid derivatives

Alkyl (Z)-2-[(E)-2-ethoxycarbonyl-2-(2-pyridinyl)ethenyl]amino-3-dimethylam inopropenoates 7 and 8 were prepared from ethyl 2-pyridinylacetate (1) in t wo steps. Substitution of the dimethylamino group with alkyl-, aryl-, or he teroarylamines afforded the corresponding beta -alkyl- 22-24, beta -aryl- 2 5-35, and beta -herteroaryl-amino-alpha,beta -didehydro-alpha -amino acid 3 6 and 37 derivatives, intermediates for further preparation of various hete rocyclic systems. The orientation around both double bonds were determined by various nmr techniques.