RCS-4 N-(5-hydroxypentyl) metabolite-d5 is intended for use as an internal standard for the quantification of RCS-4 N-(5-hydroxypentyl) metabolite by GC- or LC-MS. RCS-4 (Item No. 10645) is structurally similar to certain JWH compounds, synthetic cannabinoids used in herbal mixtures meant to mimic cannabis. RCS-4 itself has been identified in herbal mixtures.1 RCS-4 N-(5-hydroxypentyl) metabolite (Item No. 10935) is a potential metabolite of RCS-4. A similar JWH metabolite has been detected in human urine following JWH smoking.2 This metabolite is almost completely glucuroconjugated in urine samples, requiring enzymolysis of the sample before analysis.2 This product is intended for research and forensic applications.WARNING This product is not for human or veterinary use.