A cyanobacterial toxin that targets protein and glutathione synthesis in hepatocytes (IC50s = 1.3 and 2.4 µM, respectively), inhibits uridine monophosphate synthase complex activity (Ki = 10 µM), and induces DNA damage.

A cell-permeable, stable free radical that is commonly used to evaluate the ability of compounds to act as free radical scavengers or hydrogen donors and to measure the antioxidant activity of tissue extracts; followed by color change from purple (absorbance at 515-528 nm) to yellow.

A toxin produced by cyanobacteria that inhibits the catalytic activity of protein phosphatases PP1C, PP1γ, and PP2A with Ki values of 0.15, 0.24, and 0.018 nM, respectively.

A central nervous system modulator that is used to experimentally induce seizures in animals; used extensively to screen for compounds that block the production of nonconvulsive (absence or myoclonic) seizures.

A potent uncoupler of oxidative phosphorylation in mitochondria that disrupts ATP synthesis by transporting protons across cell membranes.

A natural fungal metabolite which reversibly interferes with protein trafficking and secretion mediated by the Golgi apparatus and endoplasmic reticulum; directly and reversibly inhibits Sec7 domain-containing GEFs which are necessary for Arf activation associated with vesicular transport (IC50 =…

An intermediate produced from vitamin D2 by cytochrome P450 isoforms in vertebrates; subsequently metabolized to 1,25-dihydroxy vitamin D2, which is an agonist for the vitamin D receptor.

An antibacterial and coccidiostat compound that shows selective toxicity for HMLER breast cancer stem cells (IC₅₀ = ~24 μM); 8 μM treatment of 4T1 and MCF-7-Ras breast cancer cell lines decreases cancer stem cell growth ~2-fold and ~3-fold, respectively; 5 mg/kg inhibits mammary…

A selective inhibitor of ABHD6 (IC₅₀ = 10 nM) with negligible activity against other serine hydrolases such as DAGLβ; used both as a probe to study ABHD6 and as a negative control for studies of DAGLβ.

A dihydropyridine L-type calcium channel antagonist that displays antihypertensive and antianginal activity; selectively inhibits adenosine A3 receptors (Ki = 3.25 µM) and CYP3A4 catalytic activity (IC₅₀ = 0.148 µM); activates TRPA1 channels, producing an increase in Ca2+…

A cyclododecadepsipeptide potassium-selective ionophore antibotic; induces apoptosis in several cell tyes, including CHO cells, by stimulating potassium efflux.

An intermediate in the pathway leading to the production of 1,25-dihydroxy vitamin D3; plasma or serum levels are commonly used as an indicator of an individual’s vitamin D status.

A glutamine analog that inhibits glutaminases (Ki = 6 µM) and other glutamine-utilizing enzymes, including cytidine triphosphate synthase.

A noncompetitive nicotinic acetylcholine receptor antagonist with preferential activity at the α3β4 subtype (IC₅₀ = 90-640 nM) compared to α4β2, α3β2, and α7 subtypes (IC₅₀s range from 1-7 μM).

An orally active broad spectrum antifungal agent that blocks ergosterol biosynthesis by inhibiting the fungal CYP isoform CYP51; potently inhibits the mammalian analog CYP51A1 (IC₅₀ = 63.5 nM), as well as a variety of other CYP isoforms.

A neurotoxin that binds to voltage-gated sodium channels (IC₅₀ = 15 nM) on neurons at the neuromuscular junction, causing the channel to open irreversibly at potentials more negative than normal, discharging action potentials repetitively; ichthyotoxic at nanomolar concentrations.

An agonist of α2 adrenergic receptors (Ki = 194 nM); used for sedation, anesthesia, and analgesia in non-human mammals.

A non-selective NSAID exhibiting IC50 values of 0.5 and 2.33 µM for human recombinant COX-1 and COX-2, respectively.

Capsaicin is the primary active component of the heat and pain-eliciting lipid-soluble fraction of the Capsicum pepper. Capsaicin is present in natural hot pepper extracts along with a number of impurities, including dihydrocapsaicin and several lesser impurities. Separation by HPLC is required in…

A potent, selective antagonist of TRPV4 channels, blocking the influx of calcium induced by the TRPV4 agonist GSK634775 with IC₅₀ values of 2, 5, and 40 nM for rat, mouse, and human isoforms, respectively; effective in vivo, as it resolves pulmonary edema resulting from myocardial…

An analog of wortmannin; irreversibly binds PI3K; inhibits recombinant PI3K and mTOR (IC₅₀ = 2.7 and 193 nM, respectively) and prevents the growth of LNCap cells (IC₅₀ = 1.46 μM).

Beraprost is an analog of prostacyclin in which the unstable enol-ether has been replaced by a benzofuran ether function. This modification increases the plasma half-life from 30 seconds to several hours, and permits the compound to be taken orally. Doses of 20-100 µg in humans, given 1 to 3…

A selective allosteric inhibitor of Bcr-Abl (IC₅₀s = 4.52, 0.38, and 0.93 µM against Bcr-Abl mutants G250E, E255V, and M351T, respectively); displays additive inhibitory activity against T315I Bcr-Abl mutants both in in vitro assays and in a recalcitrant T315I Bcr-Abl mutant mouse…

A polymethoxylated flavone that has been shown to enhance adipogenesis and lipolysis, to inhibit α-glucosidase and α-amylase activity, and to suppress the expression of genes associated with inflammation by regulating IκBα.

A neuroexcitatory amino acid that functions as a NMDA and metabotropic glutamate receptor agonist; used to induce brain lesions in animal models of cognitive dysfunction.

PGE1 is the theoretical COX metabolite of DGLA, but it is virtually undetectable in the plasma of normal humans or other animals. Its pharmacology includes vasodilation, hypotension, and anti-platelet activities. The IC₅₀ of PGE1 for the inhibition of ADP-induced human platelet…

A potent, reversible, ATP-competitive, and selective inhibitor of the Src family of protein tyrosine kinases: p56lck (IC₅₀ = 4 nM), p59fynT (IC₅₀ = 5 nM), Hck (IC₅₀ = 5 nM).

Intended for use as an internal standard for the quantification of diclofenac by GC- or LC-MS.

An analog of 1,24-dihydroxy vitamin D3 which, when used in a 4 μg/g ointment, suppresses psoriasis; inhibits the growth of both normal and psoriatic human keratinocytes (IC50 ~ 10 nM) via the vitamin D receptor; suppresses the production of RANTES and IL-8 by human dermal fibroblasts.

A small molecule inhibitor of tankyrase 1 and 2 (IC₅₀ = 11 and 4 nM, respectively); increases the protein levels of the axin-GSK3β complex and promotes the degradation of β-catenin; inhibits colony formation of APC-deficient colorectal cancer cells at 0.33 µM.

A classical inhibitor of complex I of the mitochondrial electron transport chain, inhibiting NADH/DB oxidoreductase and NADH oxidase with IC₅₀ values of 28.8 and 5.1 nM, respectively; used in animal models of Parkinson’s disease.

Myriocin is an amino fatty acid antibiotic derived from certain thermophylic fungi, in this case Mycelia sterilia. It is a potent immunosuppressant having 10- to 100-fold more activity than cyclosporin A. Myriocin is a potent inhibitor of serine palmitoyltransferase (Ki = 0.28 nM), the enzyme that…