Fmoc-Leu-OH, 35661-60-0, C21H23NO4, Mr 353.42, 100g. NPC 15199. Fmoc-Leu-OH (NPC 15199, NSC 334290) showed anti-inflammatory activity. On histologic examination after administration of arachidonic acid, NPC 15199 was found to block the recruitment of neutrophils into the inflammatory site. Fmoc-L-leucine was effective in blocking antigen arthritis in rabbits.