volatile organic compound xylene CAS:1330-20-7 KEGG:C19551 xylenes 0 xileno 106.165 xylene Xylol Xylole CHEBI:27338 106.07825 Wikipedia:Xylene methyl toluene C8H10 chebi_ontology xilenos dimethylbenzene Dimethylbenzol methyltoluene methylbenzene