Tetracyclic compounds

chemical compound

Tetracene, also called naphthacene, is a polycyclic aromatic hydrocarbon. It has the appearance of a pale orange powder. Tetracene is the four-ringed member of the series of acenes.

Chrysene is a polycyclic aromatic hydrocarbon (PAH) with the molecular formula that consists of four fused benzene rings. It is a natural constituent of coal tar, from which it was first isolated and characterized. It is also found in creosote at levels of 0.5–6 mg/kg.

Fluoranthene is a polycyclic aromatic hydrocarbon (PAH). The molecule can be viewed as the fusion of naphthalene and benzene unit connected by a five-membered ring. The chemical formula is . Although samples are often pale yellow, the compound is colorless. It is soluble in nonpolar organic solvents. It is a member of the class of PAHs known as non-alternant PAHs because it has rings other than those with six carbon atoms. It is a structural isomer of the alternant PAH pyrene. It is not as thermodynamically stable as pyrene. Its name is derived from its fluorescence under UV light.

Prismane or Ladenburg benzene is a polycyclic hydrocarbon with the formula C6H6. It is an isomer of benzene, specifically a valence isomer. Prismane is far less stable than benzene. The carbon (and hydrogen) atoms of the prismane molecule are arranged in the shape of a six-atom triangular prism—this compound is the parent and simplest member of the prismanes class of molecules. Albert Ladenburg proposed this structure for the compound now known as benzene. The compound was not synthesized until 1973.

Triphenylene is an organic compound with the formula (C6H4)3. It is a flat polycyclic aromatic hydrocarbon (PAH) that has a highly symmetric and planar structure consists of four fused benzene rings. Triphenylene has delocalized 18-π-electron systems based on a planar structure, corresponding to the symmetry group D3h. It is more resonance stable than its isomers chrysene, [[Benz(a)anthracene|benz[a]anthracene]], [[Benzo(c)phenanthrene|benzo[c]phenanthrene]], and tetracene, hence resists hydrogenation. It is a light yellow powder, insoluble in water.

'Benz[a]anthracene or benzo[a]anthracene' is a polycyclic aromatic hydrocarbon with the chemical formula C18H12. It is produced during incomplete combustion of organic matter.

Quadricyclane is a strained, multi-cyclic hydrocarbon with the formula CH2(CH)6. A volatile colorless liquid, it is highly strained molecule (78.7 kcal/mol). Isomerization of quadricyclane proceeds slowly at low temperatures. Because of quadricyclane's strained structure and thermal stability, it has been studied extensively.

Dihydroartemisinin (also known as dihydroqinghaosu, artenimol or DHA) is a drug used to treat malaria. Dihydroartemisinin is the active metabolite of all artemisinin compounds (artemisinin, artesunate, artemether, etc.) and is also available as a drug in itself. It is a semi-synthetic derivative of artemisinin and is widely used as an intermediate in the preparation of other artemisinin-derived antimalarial drugs. It is sold commercially in combination with piperaquine and has been shown to be equivalent to artemether/lumefantrine.

Tricyclobutabenzene is an aromatic hydrocarbon consisting of a benzene core with three cyclobutane rings fused onto it. This compound and related compounds are studied in the laboratory because they often display unusual conformations and because of their unusual reactivity. Tricyclobutabenzenes are isomers of radialenes and form an equilibrium with them.

'Benzo[c]phenanthrene' is a polycyclic aromatic hydrocarbon with the chemical formula . It is a white solid that is soluble in nonpolar organic solvents. It is a nonplanar molecule consisting of the fusion of four fused benzene rings. The compound is of mainly theoretical interest but it is environmentally occurring and weakly carcinogenic.

'Benzo[a]fluorene (IUPAC name, 11H-benzo[a]fluorene') is a polycyclic aromatic hydrocarbon (PAH). It is currently listed as a Group 3 carcinogen by the IARC.

Gonane (cyclopentanoperhydrophenanthrene) is a chemical compound with formula , whose structure consists of four hydrocarbon rings fused together: three cyclohexane units and one cyclopentane. It can also be viewed as the result of fusing a cyclopentane molecule with a fully hydrogenated molecule of phenanthrene, hence the more descriptive name "perhydrocyclopenta[a]phenanthrene". The non-systematic version of the above name is "cyclopentanoperhydrophenanthrene".

Glycylcyclines are a class of antibiotics derived from tetracycline. These tetracycline analogues are specifically designed to overcome two common mechanisms of tetracycline resistance, namely resistance mediated by acquired efflux pumps and/or ribosomal protection. Presently, tigecycline is the only glycylcycline approved for antibiotic use.

Oxetorone (), as oxetorone fumarate () (brand names Nocertone, Oxedix), is a serotonin antagonist, antihistamine, and alpha blocker used as an antimigraine drug. Association with hyperprolactinemia has been described and antidopaminergic actions are also suspected.

Ergostane is a tetracyclic triterpene, also known as 24S-methylcholestane. The compound itself has no known uses; however various functionalized analogues are produced by plants and animals. The most important of these are the heavily derivatised withanolides. However simpler forms do exist, such as the sterane campestane (24R-methylcholestane). Along with cholestane and stigmastane, this sterane is used as a biomarker for early eukaryotes.

Matrine is an alkaloid found in plants from the family Fabaceae. It has a variety of pharmacological effects, including in-vitro anti-cancer effects, as well as κ-opioid and μ-opioid receptor agonism.

1,9-Pyrazoloanthrone is a chemical compound that is a derivative of anthrone. It is used in biochemical studies as an inhibitor of c-Jun N-terminal kinases (JNKs).

Pallidol is a resveratrol dimer. It can be found in red wine, in Cissus pallida or in Parthenocissus laetevirens.

Octriptyline (SC-27,123) is a tricyclic antidepressant (TCA) that was never marketed.

class=skin-invert-image|thumb|right|200px|Doxycycline, a tetracyclic antibiotic. class=skin-invert-image|thumb|right|200px|Mirtazapine, a tetracyclic antidepressant.

Securinine is an alkaloid found in Securinega suffruticosa and Phyllanthus niruri.

Haematopodin is the more stable breakdown product of Haematopodin B. Both compounds are found in the mushroom Mycena haematopus, although haematopodin only occurs in trace amounts in fresh fruit bodies. Similar pigments (with the 1,3,4,5-tetrahydropyrrolo[4,3,2-de]quinoline structure), known as batzellins and damirones, have been found in sea sponges. A chemical synthesis for haematopodin was reported in 1996. Key steps in the synthesis involved the addition of 3-[(2,4-dimethoxybenzyl)amino]-1-propanol to the indolo-6,7-quinone and cyclization of the resulting adduct with trifluoroacetic acid.