Computational chemistry is a branch of chemistry that uses computer simulations to assist in solving chemical problems. It uses methods of theoretical chemistry incorporated into computer programs to calculate the structures and properties of molecules, groups of molecules, and solids. The importance of this subject stems from the fact that, with the exception of some relatively recent findings related to the hydrogen molecular ion, achieving an accurate quantum mechanical depiction of chemical systems analytically, or in a closed form, is not feasible. The complexity inherent in the many-body problem exacerbates the challenge of providing detailed descriptions of quantum mechanical systems. While computational results normally complement information obtained by chemical experiments, it can occasionally predict unobserved chemical phenomena.
Chemical species are a specific form of chemical substance or chemically identical molecular entities that have the same molecular energy level at a specified timescale. These entities are classified through bonding types and relative abundance of isotopes. Types of chemical species can be classified based on the type of molecular entity and can be either an atomic, molecular, ionic or radical species.
Corbadrine, sold under the brand name Neo-Cobefrine and also known as levonordefrin and α-methylnorepinephrine, is a catecholamine sympathomimetic used as a topical nasal decongestant and vasoconstrictor in dentistry in the United States. It is usually used in a pre-mixed solution with local anesthetics, such as mepivacaine.
John Christian Bailar Jr. was a professor of inorganic chemistry at the University of Illinois at Urbana-Champaign. He received his B.A. at the University of Colorado and his Ph.D. at the University of Michigan. His father was a member of the chemistry staff of the Colorado School of Mines.
Gepefrine, also known as 3-hydroxyamphetamine or α-methyl-meta-tyramine and sold under the brand names Pressionorm and Wintonin, is a sympathomimetic medication used as an antihypotensive agent which has been marketed in Germany.
Imuracetam is a drug of the racetam group described as a nootropic. It was under development in the 1970s but was never marketed.
Lorpiprazole (INN) is a marketed anxiolytic drug of the phenylpiperazine group. It has been described as a serotonin antagonist and reuptake inhibitor (SARI) in the same group as trazodone, nefazodone, and etoperidone.
Ampyzine, also known as dimethylaminopyrazine or as ampyzine sulfate in the case of the sulfate salt, is a drug described as a "central stimulant" or "CNS stimulant" and "euphoriant". It is said to be a monoamine oxidase inhibitor (MAOI). Ampyzine was first described in the scientific literature by 1960.
Wolfgang Kaim is a German chemist who held the chair of coordination chemistry at the University of Stuttgart. He is co-author of the internationally recognized book, Bioinorganic Chemistry which was awarded with the Literature Award of the German Chemical Industry.
Quingestanol acetate, sold under the brand names Demovis and Pilomin among others, is a progestin medication which was used in birth control pills but is no longer marketed. It is taken by mouth.
Penmesterol, or penmestrol, also known as 17α-methyltestosterone 3-cyclopentyl enol ether, is a synthetic, orally active anabolic-androgenic steroid (AAS) that was developed in the early 1960s. It is the 3-cyclopentyl enol ether of methyltestosterone.
Quadrosilan is a synthetic nonsteroidal estrogen that was developed in the 1970s and that is or has been used as an antigonadotropic agent in the treatment of prostate cancer. It is an organosilicon compound, and is also known as 2,6-cisdiphenylhexamethylcyclotetrasiloxane. Quadrosilan has estrogenic activity equivalent to that of estradiol, and can produce feminization and gynecomastia as side effects in male patients.
Doisynolic acid is a synthetic, orally active, nonsteroidal estrogen that was never marketed. The reaction of estradiol or estrone with potassium hydroxide, a strong base, results in doisynolic acid as a degradation product, which retains high estrogenic activity, and this reaction was how the drug was discovered, in the late 1930s. The drug is a highly active and potent estrogen by the oral or subcutaneous route. The reaction of equilenin or dihydroequilenin with potassium hydroxide was also found to produce bisdehydrodoisynolic acid, whose levorotatory isomer is an estrogen with an "astonishingly" high degree of potency, while the dextrorotatory isomer is inactive. Doisynolic acid was named after Edward Adelbert Doisy, a pioneer in the field of estrogen research and one of the discoverers of estrone.
Flumexadol (INN) is a drug described and researched as a non-opioid analgesic which was never marketed. It has been found to act as an agonist of the serotonin 5-HT1A and 5-HT2C receptors and, to a much lesser extent, of the 5-HT2A receptor. According to Nilsson (2006) in a paper on 5-HT2C receptor agonists as potential anorectics, "The (+)-enantiomer of this compound showed [...] affinity for the 5-HT2C receptor (Ki) 25 nM) [...] and was 40-fold selective over the 5-HT2A receptor in receptor binding studies. The racemic version [...], also known as 1841 CERM, was originally reported to possess analgesic properties while no association with 5-HT2C receptor activity was mentioned." It is implied that flumexadol might be employable as an anorectic in addition to analgesic. Though flumexadol itself has never been approved for medical use, oxaflozane is a prodrug of the compound that was formerly used clinically in France as an antidepressant and anxiolytic agent.
The fluoronickelates are a class of chemical compounds containing an anion with nickel at its core, surrounded by fluoride ions which act as ligands. This makes it a fluoroanion. The nickel atom can be in a range of oxidation states from +2, +3 to +4. The hexafluoronickelate(IV)2− ion NiF62− contains nickel in the maximal +4 state, and is in octahedral coordination by the fluoride atoms. It forms a commercially available salt Potassium hexafluoronickelate(IV) K2NiF6. Solid double salts can also contain tetrafluoronickelate NiF4 eg K2NiF4.
Spirorenone (INN) is a steroidal antimineralocorticoid of the spirolactone group that was never marketed. Spirorenone possesses 5–8 times the antimineralocorticoid activity of spironolactone in animal studies. The initial discovery of spirorenone was deemed a great success, as no compound with greater antimineralocorticoid activity had been developed since spironolactone in 1957. Moreover, spirorenone itself has virtually no affinity for the androgen receptor while its progestogenic activity shows species differences, being somewhat greater than that of spironolactone in rabbits but absent in mice and rats. As such, it was characterized as a highly potent antimineralocorticoid with far fewer hormonal side effects relative to spironolactone.
Allenestrol, or allenoestrol, also known as α,α-dimethyl-β-ethylallenolic acid or as methallenestrilphenol, is a synthetic, nonsteroidal estrogen and a derivative of allenolic acid that was never marketed. A methyl ether of allenestrol, methallenestril (methallenestrol), is also an estrogen, but, in contrast to allenestrol, has been marketed.
Spiroxasone is a synthetic, steroidal antimineralocorticoid of the spirolactone group which was developed as a diuretic and antihypertensive agent but was never marketed. It was synthesized and assayed in 1963. The drug is 7α-acetylthiospirolactone with the ketone group removed from the C17α spirolactone ring. Similarly to other spirolactones like spironolactone, spiroxasone also possesses antiandrogen activity.
Salmefamol is a drug of the phenethylamine and amphetamine families described as a bronchodilator which was never marketed. It is a β-adrenergic receptor agonist with some selectivity for the β2-adrenergic receptor and has been described as a "sister compound" to salbutamol. However, the drug is more potent (1.5-fold), longer-acting, and more lipophilic in comparison to salbutamol. It was intended for inhalational or intravenous administration. Salmefamol was first described in the literature by 1968.
Clofenetamine, also known as phenoxethamine or as Keithon, is a drug described as a tranquilizer, antihistamine, anticholinergic, and antiparkinsonian agent. It is a derivative of diphenhydramine and is closely structurally related to mephenhydramine, chlorphenoxamine, and embramine, among other drugs. Clofenetamine was discovered by Searle in the 1940s and was first described in the literature by 1956.
