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Names | |
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IUPAC name Dendroban-12-one | |
Systematic IUPAC name (2aS,2a1R,4aS,5R,8R,8aS,9S)-1,2a1-Dimethyl-9-(propan-2-yl)decahydro-6H-7-oxa-1-aza-5,8-methanocyclopenta[cd]azulen-6-one | |
Identifiers | |
3D model (JSmol) | |
ChEBI | |
ChemSpider | |
KEGG | |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
C16H25NO2 | |
Molar mass | 263.381 g·mol−1 |
Appearance | Colorless solid |
Melting point | 136 °C (277 °F; 409 K) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Dendrobine is an alkaloid found in Dendrobium nobile at an average of 0.5% by weight. [1] It is a colorless solid at room temperature. It is related to the picrotoxin family of natural products. When given a fatal dose, death is usually caused by convulsions. [1] It possesses a molecular structure that attracted interest in its total synthesis by organic chemists.
There have been 3 successful enantioselective syntheses of dendrobine reported with yields ranging from 0.2-4.0%. The structure of dendrobine is intriguing due to its tetracyclic ring system with seven contiguous stereocenters. Most recently, a full synthesis of (-)-dendrobine was carried out by Kreis et al. with a yield of 4.0%. [1] The novelty of Kreis' synthesis is the key reaction cascade with an amine functioning as the linchpin that initiates the sequence of reactions while embedding itself in the target structure. This reaction cascade occurs stereoselectively only when it is carried out without isolation of intermediates. The cascade successfully installs a key quaternary center while simultaneously designating a stereosymetric carbon center.
While dendrobine's effects on humans have not been studied extensively, studies of its pharmacological effects on various small animals were conducted in 1935 by Chen and Chen. [2] It was concluded that dendrobine exhibited a weak analgesic effect when administered to mice (5–15 mg/kg), and an antipyretic effect when administered to rabbits (8.5 mg/kg). [2] Hypotensive effects were reported in experiments with frogs, cats, and a dog.
The minimum lethal doses by intravenous injection are 20 mg/kg for mice and rats, 22 mg/kg in guinea pigs, and 17 mg/kg in rabbits. [2] Dendrobine is a strongly selective competitive antagonist of β-alanine, taurine, and glycine. [3] While structurally related to picrotoxinin, dendrobine is not an antagonist of GABA.
Aconitine is an alkaloid toxin produced by various plant species belonging to the genus Aconitum, known also commonly by the names wolfsbane and monkshood. Monkshood is notorious for its toxic properties.
Salvinorin A is the main active psychotropic molecule in Salvia divinorum. Salvinorin A is considered a dissociative hallucinogen.
Muscimol is one of the principal psychoactive constituents of Amanita muscaria and related species of mushroom. Muscimol is a potent and selective orthosteric agonist for the GABAA receptors and displays sedative-hypnotic, depressant and hallucinogenic psychoactivity. This colorless or white solid is classified as an isoxazole.
Synephrine, or, more specifically, p-synephrine, is an alkaloid, occurring naturally in some plants and animals, and also in approved drugs products as its m-substituted analog known as neo-synephrine. p-Synephrine and m-synephrine are known for their longer acting adrenergic effects compared to epinephrine and norepinephrine. This substance is present at very low concentrations in common foodstuffs such as orange juice and other orange products, both of the "sweet" and "bitter" variety. The preparations used in traditional Chinese medicine (TCM), also known as Zhi Shi (枳实), are the immature and dried whole oranges from Citrus aurantium. Extracts of the same material or purified synephrine are also marketed in the US, sometimes in combination with caffeine, as a weight-loss-promoting dietary supplement for oral consumption. While the traditional preparations have been in use for millennia as a component of TCM-formulas, synephrine itself is not an approved over the counter drug. As a pharmaceutical, m-synephrine (phenylephrine) is still used as a sympathomimetic, mostly by injection for the treatment of emergencies such as shock, and rarely orally for the treatment of bronchial problems associated with asthma and hay-fever.
Epibatidine is a chlorinated alkaloid that is secreted by the Ecuadoran frog Epipedobates anthonyi and poison dart frogs from the Ameerega genus. It was discovered by John W. Daly in 1974, but its structure was not fully elucidated until 1992. Whether epibatidine is the first observed example of a chlorinated alkaloid remains controversial, due to challenges in conclusively identifying the compound from the limited samples collected by Daly. By the time that high-resolution spectrometry was used in 1991, there remained less than one milligram of extract from Daly's samples, raising concerns about possible contamination. Samples from other batches of the same species of frog failed to yield epibatidine.
D-Lysergic acid α-hydroxyethylamide, also known as D-lysergic acid methyl carbinolamide, is an alkaloid of the ergoline family, believed to be present in various species in the Convolvulaceae, as well as some species of fungi. Morning glory heavenly blue and Hawaiian baby woodrose especially contain high amounts of LSH, with content varying between species and by how fresh.
Arecoline is a nicotinic acid-based mild parasympathomimetic stimulant alkaloid found in the areca nut, the fruit of the areca palm. It is an odourless oily liquid. It can bring a sense of enhanced alertness and energy, euphoria and relaxation. Its psychoactive effects are comparable to that of nicotine.
Hordenine is an alkaloid of the phenethylamine class that occurs naturally in a variety of plants, taking its name from one of the most common, barley. Chemically, hordenine is the N-methyl derivative of N-methyltyramine, and the N,N-dimethyl derivative of the well-known biogenic amine tyramine, from which it is biosynthetically derived and with which it shares some pharmacological properties. As of September 2012, hordenine is widely sold as an ingredient of nutritional supplements, with the claims that it is a stimulant of the central nervous system, and has the ability to promote weight loss by enhancing metabolism. In experimental animals, given sufficiently large doses parenterally, hordenine does produce an increase in blood pressure, as well as other disturbances of the cardiovascular, respiratory, and nervous systems. These effects are generally not reproduced by oral administration of the drug in test animals, and virtually no scientific reports of the effects of hordenine in human beings have been published.
Aporphine is an alkaloid with the chemical formula C17H17N. It is the core chemical substructure of the aporphine alkaloids, a subclass of quinoline alkaloids. It can exist in either of two enantiomeric forms, (R)-aporphine and (S)-aporphine.
Methyllycaconitine (MLA) is a diterpenoid alkaloid found in many species of Delphinium (larkspurs). In common with many other diterpenoid alkaloids, it is toxic to animals, although the acute toxicity varies with species. Early research was focused on identifying, and characterizing the properties of methyllycaconitine as one of the principal toxins in larkspurs responsible for livestock poisoning in the mountain rangelands of North America. Methyllycaconitine has been explored as a possible therapeutic agent for the treatment of spastic paralyses in man, and it has been shown to have insecticidal properties. Most recently, it has become an important molecular probe for studying the pharmacology of the nicotinic acetylcholine receptor.
Etoxadrol (CL-1848C) is a dissociative anaesthetic drug that has been found to be an NMDA antagonist and produce similar effects to PCP in animals. Etoxadrol, along with another related drug dexoxadrol, were developed as analgesics for use in humans, but development was discontinued in the late 1970s after patients reported side effects such as nightmares and hallucinations.
Histrionicotoxins are a group of related toxins found in the skin of poison frogs from the family Dendrobatidae, notably Oophaga histrionica, which are native to Colombia. It is likely that, as with other poison frog alkaloids, histrionicotoxins are not manufactured by the amphibians, but absorbed from insects in their diet and stored in glands in their skin. They are notably less toxic than other alkaloids found in poison frogs, yet their distinct structure acts as a neurotoxin by non-competitive inhibition of nicotinic acetylcholine receptors.
Phenylethanolamine, or β-hydroxyphenethylamine, is a trace amine with a structure similar to those of other trace phenethylamines as well as the catecholamine neurotransmitters dopamine, norepinephrine, and epinephrine. As an organic compound, phenylethanolamine is a β-hydroxylated phenethylamine that is also structurally related to a number of synthetic drugs in the substituted phenethylamine class. In common with these compounds, phenylethanolamine has strong cardiovascular activity and, under the name Apophedrin, has been used as a drug to produce topical vasoconstriction.
N-Methyltyramine (NMT), also known as 4-hydroxy-N-methylphenethylamine, is a human trace amine and natural phenethylamine alkaloid found in a variety of plants. As the name implies, it is the N-methyl analog of tyramine, which is a well-known biogenic trace amine with which NMT shares many pharmacological properties. Biosynthetically, NMT is produced by the N-methylation of tyramine via the action of the enzyme phenylethanolamine N-methyltransferase in humans and tyramine N-methyltransferase in plants.
Candicine is a naturally occurring organic compound that is a quaternary ammonium salt with a phenethylamine skeleton. It is the N,N,N-trimethyl derivative of the well-known biogenic amine tyramine, and, being a natural product with a positively charged nitrogen atom in its molecular structure, it is classed as an alkaloid. Although it is found in a variety of plants, including barley, its properties have not been extensively studied with modern techniques. Candicine is toxic after parenteral administration, producing symptoms of neuromuscular blockade; further details are given in the "Pharmacology" section below.
N,N-Dimethyldopamine (DMDA) is an organic compound belonging to the phenethylamine family. It is related structurally to the alkaloid epinine (N-methyldopamine) and to the major neurotransmitter dopamine (of which it is the N,N-dimethylated analog). Because of its structural relationship to dopamine, DMDA has been the subject of a number of pharmacological investigations. DMDA has been detected in Acacia rigidula.
Gelsemine (C20H22N2O2) is an indole alkaloid isolated from flowering plants of the genus Gelsemium, a plant native to the subtropical and tropical Americas, and southeast Asia, and is a highly toxic compound that acts as a paralytic, exposure to which can result in death. It has generally potent activity as an agonist of the mammalian glycine receptor, the activation of which leads to an inhibitory postsynaptic potential in neurons following chloride ion influx, and systemically, to muscle relaxation of varying intensity and deleterious effect. Despite its danger and toxicity, recent pharmacological research has suggested that the biological activities of this compound may offer opportunities for developing treatments related to xenobiotic or diet-induced oxidative stress, and of anxiety and other conditions, with ongoing research including attempts to identify safer derivatives and analogs to make use of gelsemine's beneficial effects.
Halostachine is a natural product, an alkaloid first isolated from the Asian shrub Halostachys caspica, and structurally a β-hydroxy-phenethylamine related to its better-known "parent" biogenic amine, phenylethanolamine, to the adrenergic drug synephrine, and to the alkaloid ephedrine. The pharmacological properties of halostachine have some similarity to those of these structurally-related compounds, and Halostachys caspica extracts have been included as a constituent of certain OTC dietary supplements, but halostachine has never been developed as a prescription drug. Although it is found in nature as a single stereoisomer, halostachine is more commonly available as a synthetic product in the form of its racemate. In appearance it is a colorless solid.
Lomerizine (INN) is a diphenylpiperazine class L-type and T-type calcium channel blocker. This drug is currently used clinically for the treatment of migraines, while also being used experimentally for the treatment of glaucoma and optic nerve injury.
14-Hydroxygelsenicine (HGE) is a gelsedine-type indole alkaloid naturally found in some plants of the Gelsemium genus. G. elegans was used in traditional Chinese medicine as a remedy for a plethora of conditions such as skin ulcers and dermatitis, pain related to cancer, rheumatic arthritis, psoriasis as well as to treat bone fractures. It can also be found under the names “Duan Chang Cao”, “Gou Wen” and “heartbreak grass”. G. elegans is also known for its toxic effects; it is used by hilltribes of southeastern Asia as an effective means of committing suicide and has been linked to certain types of toxic honey, where HGE was the most abundant component. Gelsedine-type alkaloids from G. elegans usually express high toxicity, with gelsenicine being one of the most toxic. However, toxicity of HGE has not yet been thoroughly researched. More recent studies have shown that alkaloids derived from G. elegans have anti-tumor, anti-inflammatory, analgesic, and immunomodulation properties, with the toxic dose being close to the therapeutic dose.