1-Cyano-3-butene 3-Butenyl cyanide 4-Cyano-1-butene 4-PENTENENITRILE 4-Pentenoic acid, nitrile 4-Pentenonitrile 592-51-8 Allylacetonitrile Allylmethyl cyanide EINECS 209-762-0 HSDB 5709