... The presence in the ir of a strong conjugated nitrile at 2190 cm-' f 10 for thiazoline-2-acetic esters, 11, made it possible to differentiate 11 from thiophene 8 or to detect 11 in mixtures. ... Page 6. CANADIAN JOURNAL OF CHEMISTRY. VOL. 48, 1970 3 2 h - - -- U - > --- ...