Rose Bengal lactone is a polyhalogenated derivative of Fluorescein. Rose Bengal lactone is a dye compound described to produce cell membrane damage. Rose Bengal lactone and other Fluorescein derivatives are also described to modulate the function of ATP-sensitive K+ channels. Rose bengal lactone reacts readily with bases so treatment with triethylamine immediately yields the Rose Bengal salt.

Hyodeoxycholic acid, also known as HDCA, is a secondary bile acid. Natural 6alpha-hydroxylated bile acids are receptor-specific activators of nuclear liver X receptor alpha (LXRalpha), a nuclear receptor regulating the expression of the cholesterol 7alpha-hydroxylase gene. AHRO-001 (Hyodeoxycholic acid) is in phase I clinical trials for the treatment of atherosclerosis. Through a complex signaling processes utilizing LXR receptors, the compound is designed to increase the efficiency of cholesterol efflux using the HDL cells, which act on all cholesterol in the arterial circulation as well as in the lipid core of plaque deposits in the artery walls. Use of AHRO-001 has shown no adverse effects on morbidity, mortality or toxicity and has been well tolerated at high doses.

Arecoline is a natural alkaloid and is an effective constituent of Areca catechu L. (Arecaceae) with various pharmacological activities including effects on nervous, cardiovascular, digestive and endocrine systems and anti-parasitic effects. Antinociception of arecoline is mediated by the activation of the muscarinic acetylcholine receptors. It was found that this compound leads to oral submucosal fibrosis and oral cancer. Lung cancer is a severe type of carcinoma with high cell motility that is difficult to treat. As a result, further studies are needed to reduce or eliminate the toxicity of the compound before developing into a new drug.

Urocanic acid is a breakdown (deamination) product of histidine. In the liver, urocanic acid is an intermediate in the conversion of histidine to glutamic acid, whereas in the epidermis, it accumulates and may be both a UV protectant and an immunoregulator. Urocanic acid (UA) exists as a trans isomer (t-UA, approximately 30 mg/cm2) in the uppermost layer of the skin (stratum corneum). t-UA is formed as the cells of the second layer of skin become metabolically inactive. During this process, proteins and membranes degrade, histidine is released, and histidase (histidine ammonia lyase) catalyzes the deamination of histidine to form t-UA. t-UA accumulates in the epidermis until removal by either the monthly skin renewal cycle or sweat. Upon absorption of UV light, the naturally occurring t-UA isomerizes to its cis form, c-UA. Because DNA lesions (e. g. , pyrimidine dimers) in the lower epidermis can result from UV-B absorption, initial research proposed that t-UA acted as a natural sunscreen absorbing UV-B in the stratum corneum before the damaging rays could penetrate into lower epidermal zones. c-UA also suppresses contact hypersensitivity and delayed hypersensitivity, reduces the Langerhans cell count in the epidermis, prolongs skin-graft survival time, and affects natural killer cell activity. It has also been proposed that c-UA may mediate the transient alteration in immune surveillance resulting in immunosuppression induced after UV-irradiation, by interacting with immune cells locally and/or systemically to generate T cells with suppressor function.

Gaboxadol (or THIP) is a direct GABA mimetic ligand at delta-containing receptors. Gaboxadol went into human clinical trials to test if the drug promoted sleep. It was generally well tolerated. Gaboxadol enhances delta power in NREM sleep in humans. Gaboxadol failed in Phase III for sleep studies. The side effects of Gaboxadol have been described as mild and similar in quality to those of other GABA-mimetics. Gaboxadol is in development with Ovid Therapeutics as a treatment for Angelman syndrome, fragile X syndrome and epilepsy.

Descinolone acetonide (an analog of triamcinolone acetonide) is a glucocorticoid which was developed for the treatment of skin disorders. It was tested on patients with psoriasis and atopic dermatitis, however there is no information about its further development.

Growth hormone releasing hexapeptide (GHRP-6) is a synthetic met-enkephalin analog that induces the release of growth hormone in vivo through binding of the ghrelin receptor. GHRP-6 increases proliferation in astrocytes through a mechanism that involves PI3K/Akt signaling. GHRP-6 also inhibits development of restraint stress-induced gastric lesions and reverses ovariectomy-induced effects on serum glucose and insulin levels. Additionally, GHRP-6 decreases locomotor activity and increases food intake in vivo. Essentially a synthetic version of ghrelin analogue, GHRP-6 (like GHRP-2) stimulates the release of an endogenous growth hormone (GH) within the somatotropes of the anterior pituitary in the animal and human body. Specifically, GHRP-6 will increase the number of somatotropes in a GH pulse by limiting the amount of somatostatin present, while standard GHRH increases the amplitude at which the pituitary cells pulse. Unlike ghrelin, GHRP-6 is not specifically used to increase appetite, but it may have secondary actions that impact hypothalamic neurons. These effects last for approximately an hour after the initial application, which mimics the natural application of GH, and consists of an eight hour circulation period. In studies GHRP-6 has shown biological actions similar to the naturally occurring hunger stimulating peptide ghrelin. Its main use is to promote food intake by stimulating hunger and aid in energy metabolism. It can be used in the treatment of GH deficiency as well as cachexia, eating disorders and obesity. GHRP-6 is a synthetic met-enkephalin (a naturally occurring opioid growth factor) analog. GHRP-6 contains D-amino acids that are entirely synthetic, lacks opioid activity, and shares no sequence relation with GHRH. It has also been shown that GHRP-6 can lead to re-stimulation of the natural production of HGH. Studies have shown that GHRP-6 increases the secretion of IGF-1 (InsulinLike Growth Factor 1) by the liver, which is speculated to be a required component in the anabolic mechanisms leading to the action of HGH. It also appears that GHRP-6 has positive implications for the central nervous system, as ghrelin is known to protect neurons.

F-15599 is a novel agonist with high selectivity and efficacy at serotonin 5-HT(1A) receptors. In signal transduction, electrophysiological and neurochemical tests, F-15599 preferentially activates post-synaptic 5-HT(1A)Rs in rat frontal cortex. Such a profile may translate to an improved profile of therapeutic activity for mood disorders. [(18)F]F-15599 is a radiofluorinated agonist presenting interesting characteristics for probing in vitro and in vivo the high-affinity states of the 5-HT(1A) receptors. The Rett Syndrome Research Trust awarded a grant to Neurolixis to advance F-15599 to clinical development.