np7b00946_si_001.pdf (326.57 kB)
Iodine-Promoted Aromatization of p‑Menthane-Type Phytocannabinoids
journal contribution
posted on 2017-12-14, 19:22 authored by Federica Pollastro, Diego Caprioglio, Patrizia Marotta, Aniello Schiano Moriello, Luciano De Petrocellis, Orazio Taglialatela-Scafati, Giovanni AppendinoTreatment with iodine cleanly converts
various p-menthane-type phytocannabinoids and their
carboxylated precursors
into cannabinol (CBN, 1a). The reaction is superior to
previously reported protocols in terms of simplicity and substrate
range, which includes not only tricyclic tetrahydrocannabinols such
as Δ9-THC (2a) but also bicyclic phytocannabinoids
such as cannabidiol (CBD, 3a). Lower homologues from
the viridin series (2c and 3c, respectively)
afforded cannabivarin (CBV), a non-narcotic compound that, when investigated
against a series of ionotropic (thermo-TRPs) biological end-points
of phytocannabinoids, retained the submicromolar TRPA1-activating
and TRPM8-inhibiting properties of CBN, while also potently activating
TRPV2. Treatment with iodine provides an easy access to CBN (1a) from crude extracts and side-cuts of the purification
of Δ9-THC and CBD from respectively narcotic Cannabis sativa (marijuana) and fiber hemp, substantially
expanding the availability of this compound and, in the case of fiber
hemp, dissecting it from narcotic phytocannabinoids.