hydrate cetylpyridinium chloride monohydrate 1-hexadecylpyridinium chloride monohydrate 1-hexadecylpyridinium chloride--water (1/1) 357.280 358.00100 C21H38N.H2O.Cl C21H40ClNO CAS:6004-24-6 CHEBI:3566 Gmelin:717786 InChI=1S/C21H38N.ClH.H2O/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-16-19-22-20-17-15-18-21-22;;/h15,17-18,20-21H,2-14,16,19H2,1H3;1H;1H2/q+1;;/p-1 KEGG:C11307 KEGG:D01062 NFCRBQADEGXVDL-UHFFFAOYSA-M O.[Cl-].CCCCCCCCCCCCCCCC[n+]1ccccc1 cetylpyridinium chloride monohydrate chebi_ontology