4-Phenylbutyric acid (Benzenebutyric acid) is a histone deacetylase (HDAC) inhibitor and an endoplasmic reticulum stress (ERS) inhibitor. 4-Phenylbutyric acid can be used to treat urea cycle disorders.

Valproic acid sodium salt (Sodium Valproate) is the sodium salt form of valproic acid with anti-epileptic activity. Valproic acid sodium salt is converted into its active form, valproate ion, in blood. Although the mechanism of action remains to be elucidated, Valproic acid sodium salt increases concentrations of gamma-aminobutyric acid (GABA) in the brain, probably due to inhibition of the enzymes responsible for the catabolism of GABA. This potentiates the synaptic actions of GABA. Valproic acid sodium salt may also affect potassium channels, thereby creating a direct membrane-stabilizing effect.

Panobinostat (NVP-LBH589) is a broad-spectrum HDAC inhibitor (IC50=5 nM) with oral activity and non-selectivity. Panobinostat has antitumor activity and induces apoptosis and autophagy.

Gilteritinib (ASP2215) is a potent inhibitor of FMS-related tyrosine kinase 3 (FLT3) and AXL tyrosine kinase receptors (IC50 = 0.29 nM and <1 nM, respectively). In preclinical studies, gilteritinib demonstrated strong antileukemic and antitumor effects. Gilteritinib is currently in several Phase 3 clinical trials for acute myeloid leukemia.

Theophylline monohydrate (Quibron) appears to inhibit phosphodiesterase and prostaglandin production, regulate calcium flux and intracellular calcium distribution, and antagonize adenosine. Theophylline monohydrate is a natural alkaloid derivative of xanthine isolated from the plants Camellia sinensis and Coffea arabica. Physiologically, this agent relaxes the bronchial smooth muscle, produces vasodilation (except in cerebral vessels), stimulates the CNS, stimulates the cardiac muscle, induces diuresis, and increases gastric acid secretion; it may also suppress inflammation and improve contractility of the diaphragm.

Theophylline (1,3-Dimethylxanthine) is a methyl xanthine derivative from tea with diuretic, smooth muscle relaxant, bronchial dilation, cardiac, and central nervous system stimulant activities. It inhibits the 3', 5'-cyclic nucleotide phosphodiesterase that degrades cyclic AMP, thus potentiating the actions of agents that act through adenylyl cyclases and cyclic AMP.

Vorinostat (SAHA) is a pan-histone deacetylase (HDAC) inhibitor (IC50=10 nM) with inhibitory activity against HDAC1/2/3/6/7/11. Vorinostat has antitumor activity, induces cell differentiation, blocks the cell cycle and induces apoptosis.

Nintedanib (Intedanib) is a triple vascular kinase inhibitor that inhibits VEGFR1, VEGFR2, and VEGFR3 (IC50=34/13/13 nM), FGFR1, FGFR2, and FGFR3 (IC50=69/37/108 nM), PDGFRα, and PDGFRβ (IC50=59/65 nM). Nintedanib has antitumor activity and inhibits tumor growth by inhibiting angiogenesis.