Leelamine hydrochloride, a tricyclic diterpene extracted from pine tree bark, inhibits the transcriptional activity of the androgen receptor, known to regulate fatty acid synthesis [2,3]. This compound acts as a cannabinoid receptor type 1 (CB1) agonist and suppresses SREBP1-regulated fatty acid/lipid synthesis in prostate cancer cells, irrespective of androgen receptor status.
Cylindrospermopsin, a tricyclic uracil derivative, is a cyanobacterial toxin that was first discovered in an algal bloom contaminating a local drinking supply on Palm Island in Queensland, Australia after an outbreak of a mysterious disease. Cylindrospermopsin targets protein and glutathione synthesis in hepatocytes (IC50s = 1.3 and 2.4 µM, respectively), leading to cell death. [1] It has been shown to inhibit the activity of the uridine monophosphate synthase complex with a Ki value of 10 µM.[2] Cylindrospermopsin is genotoxic, inducing DNA damage as evidenced by double strand breaks and reducing cell viability in HepG2 cells at 0.1-0.5 µg/ml.[3]
5-Hydroxy-8-methoxypsoralen (5-Hydroxyxanthotoxin) is a metabolite derived from Xanthotoxin, which acts as a potent tricyclic furocoumarin suicide inhibitor of CYP (cytochrome P-450). It is employed as an agent for the treatment of psoriasis, eczema, vitiligo, and certain cutaneous Lymphomas, in combination with phototherapy involving exposure to sunlight.