2-Chloro-5H-pyrrolo[2,3-B]pyrazine889447-19-232 % similar 1H-Imidazole-5-carbonitrile57090-88-731 % similar 4-Cyanoindole16136-52-031 % similar Pyridazine-3-carbonitrile53896-49-431 % similar Indole120-72-930 % similar 5-(Bromomethyl)pyridine-2-carbonitrile308846-06-230 % similar