摘要:
Potential chelating-forming ligands and reagents for heterocyclization - ethyl esters of 4-[N-(R-pyrid-2-yl)carbamoyl]-3-amino-2-cyanobuten-2-oic acids ["co-dimers" of cyanoacetic acid ethyl ester (EECA) and the corresponding (pyrid-2-yl) amides of this same acid) - were synthesized in two ways: by condensation of 2-dialkylborylamidopyridines (picolines) with EECA (via chelate compounds of boron) and by the reaction of EECA dimer with 2-aminopyridines (picolines).