Total synthesis and properties of prostaglandins 35. Synthesis and properties of 4-carbomethoxy-alkylaminomethylene-(+)2-oxabicyclo[3.3.0]-6-octen-3-ones

Reaction of (+)4-mesyloxymethylene-2-oxabicyclo[3.3.0]-6-octen-3-one with Ω-amino acids of different lengths gave (+)4-carbomethoxyalkylaminomethylene-2-oxabicyclo[3.3.0]-6-octen-3-ones. For the γ-aminobutyric ester, the corresponding aminomethylene derivative was obtained both in the linear and the cyclic forms. Acylations of the synthesized enamino lactones by acetyl and benzoyl chlorides were investigated.