1-Pentyl-3-(1-naphthoyl)pyrrole, the archetype of the naphthoylpyrroles, introduced in Lainton, Huffman, Martin and Compton, '1-Alkyl-3-(1-naphthoyl)pyrroles: a new class of cannabinoid' (Tetrahedron Lett. 36:1401–1404, 1995). A CB1 partial agonist, Ki 87 nM — roughly half THC's potency — and the demonstration that the indole ring could be cut down to a pyrrole.