E. Bunuel et al., N-[BIS(METHYLTHIO)METHYLENE]-DIDEHYDROALANINE METHYL-ESTER A NEW AND EXCELLENT DIENOPHILE FOR THE SYNTHESIS OF 2-AMINONORBORNENE-2-CARBOXYLIC ACID, Tetrahedron, 49(33), 1993, pp. 7287-7294
N-[Bis(methylthio)methylene]-didehydroalanine methyl ester behaves as
an excellent dienophile with cyclopentadiene to afford methyl hylthio)
methylene]-2-aminonorbornene-2-carboxylate in excellent yield and with
high selectivity.