1-Nitroso-1,2,5,6-tetrahydronicotinic acid methyl ester 3-Pyridinecarboxylic acid, 1,2,5,6-tetrahydro-1-nitroso-, methyl ester 5-22-01-00325 (Beilstein Handbook Reference) 55557-02-3 BRN 0391077 CCRIS 3050 N-NITROSOGUVACOLINE N-Nitrosoguvacine Nicotinic acid, 1,2,5,6-tetrahydro-1-nitroso-, methyl ester Nitrosoguvacoline