4-(1-Pyrenyl)butyl methylphosphonofluoridate 67000-88-8 BRN 2163126 Methylphosphonofluoridic acid 4-(1-pyrenyl)butyl ester Phosphonofluoridic acid, methyl-, 4-(1-pyrenyl)butyl ester Pyrenebutyl-methylphosphonofluoridate