Loratadine Impurity: 4-[8-?chloro-?5,?6-?dihydro-?2-?(hydroxymethyl)?-?11H-? benzo[5,?6]?cyclohepta[1,?2-?b]?pyridin-?11-?ylidene]?-1-? Piperidinecarboxylic acid ethyl ester(2-Hydroxymethyl.