91788-22-6Relevant articles and documents
PYRYLIUM-MEDIATED TRANSFORMATIONS OF NATURAL PRODUCTS. PART 3. SYNTHESIS OF WATER-SOLUBLE PYRYLIUM SALTS AND THEIR PREPARATIVE REACTIONS WITH AMINES
Katritzky, Alan R.,Yang, Yu-Kun,Gabrielsen, Bjarne,Marquet, Jorge
, p. 857 - 866 (2007/10/02)
A series of water-soluble pyrylium salts and zwitterions has been prepared containing two or three carboxylic or sulphonic acid groups.These pyrylium salts react in aqueous solution with ammonia to give the corresponding pyridines and with n-butylamine, benzylamine, and ω-amino groups of lysine to give the corresponding pyridinium systems, usually as betaines.The pyridinium betainess (m.p > 300 deg C) show characteristic 13C n.m.r. spectra which have been nearly fully assigned.