1-Methyl-4-hydroxy-1,2,5,6-tetrahydronicotinic acid ethyl ester 1-Methyl-4-hydroxy-1,2,5,6-tetrahydronicotinsaeureaethylester [German] 3-Pyridinecarboxylic acid, 1,2,5,6-tetrahydro-4-hydroxy-1-methyl-, ethyl ester 37673-68-0