JWH-398 is an analgesic chemical from the naphthoylindole family, which acts as a cannabinoid agonist at both the CB1 and CB2 receptors. It has mild selectivity for CB1 with a Ki of 2.3nM and 2.8nM at CB2. It was identified by the EMCDDA as an ingredient in three separate "herbal incense" products purchased from online shops between February to June 2009. It was discovered by, and named after, Dr. John W. Huffman.
^John W. Huffman, et al. STRUCTURE-ACTIVITY RELATIONSHIPS AT THE CB1 AND CB2 RECEPTORS FOR 1-ALKYL-3-(1-NAPHTHOYL-4 AND 8-HALOGEN SUBSTITUTED) INDOLES (2009) 19th Annual Symposium on the Cannabinoids, Burlington, Vermont, International Cannabinoid Research Society, Page 2.