Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar structure may also be termed alkaloids. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen, sulfur and, more rarely, other elements such as chlorine, bromine, and phosphorus.
Ergoline is a chemical compound whose structural skeleton is contained in a variety of alkaloids, referred to as ergoline derivatives or ergoline alkaloids. Ergoline alkaloids, one being ergine, were initially characterized in ergot. Some of these are implicated in the condition ergotism, which can take a convulsive form or a gangrenous form. Even so, many ergoline alkaloids have been found to be clinically useful. Annual world production of ergot alkaloids has been estimated at 5,000–8,000 kg of all ergopeptines and 10,000–15,000 kg of lysergic acid, used primarily in the manufacture of semi-synthetic derivatives.
Batrachotoxin (BTX) is an extremely potent cardio- and neurotoxic steroidal alkaloid found in certain species of beetles, birds, and frogs. The name is from the Greek word βάτραχος, bátrachos, 'frog'. Structurally-related chemical compounds are often referred to collectively as batrachotoxins. It is an extremely poisonous alkaloid. In certain frogs, this alkaloid is present mostly on the skin. Such frogs are among those used for poisoning darts. Batrachotoxin binds to, and irreversibly opens, the sodium channels of nerve cells and prevents them from closing, resulting in paralysis and death. No antidote is known.
Curare is a common name for various plant extract alkaloid arrow poisons originating from indigenous peoples in Central and South America. Used as a paralyzing agent for hunting and for therapeutic purposes, Curare only becomes active by a direct wound contamination by a poison dart or arrow or via injection. These poisons function by competitively and reversibly inhibiting the nicotinic acetylcholine receptor (nAChR), which is a subtype of acetylcholine receptor found at the neuromuscular junction. This causes weakness of the skeletal muscles and, when administered in a sufficient dose, eventual death by asphyxiation due to paralysis of the diaphragm. Curare is prepared by boiling the bark of one of the dozens of plant alkaloid sources, leaving a dark, heavy paste that can be applied to arrow or dart heads. Historically, curare has been used as an effective treatment for tetanus or strychnine poisoning and as a paralyzing agent for surgical procedures.
Macromerine is a phenethylamine derivative. It was first identified from the cactus Coryphantha macromeris. It can also be found in C. runyonii, C. elephantidens, and other related members of the family Cactaceae. The plants may have been used by Tarahumara shamans for their entheogenic effects.
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.
Pyrrolizidine alkaloids (PAs), sometimes referred to as necine bases, are a group of naturally occurring alkaloids based on the structure of pyrrolizidine. Pyrrolizidine alkaloids are produced by plants as a defense mechanism against insect herbivores. More than 660 PAs and PA N-oxides have been identified in over 6,000 plants, and about half of them exhibit hepatotoxicity. They are found frequently in plants in the Boraginaceae, Asteraceae, Orchidaceae and Fabaceae families; less frequently in the Convolvulaceae and Poaceae, and in at least one species in the Lamiaceae. It has been estimated that 3% of the world’s flowering plants contain pyrrolizidine alkaloids. Honey can contain pyrrolizidine alkaloids, as can grains, milk, offal and eggs. To date (2011), there is no international regulation of PAs in food, unlike those for herbs and medicines.
Delphinine is a toxic diterpenoid alkaloid found in plants from the Delphinium (larkspur) and Atragene genera, both in the family Ranunculaceae. Delphinine is the principal alkaloid found in Delphinium staphisagria seeds – at one time, under the name stavesacre, a very well known herbal treatment for body lice. It is related in structure and has similar effects to aconitine, acting as an allosteric modulator of voltage gated sodium channels, and producing low blood pressure, slowed heart rate and abnormal heart rhythms. These effects make it highly poisonous. While it has been used in some alternative medicines, most of the medical community does not recommend using it due to its extreme toxicity.
Ibogamine is an anti-convulsant, anti-addictive, CNS stimulant alkaloid found in Tabernanthe iboga and Crepe Jasmine. Basic research related to how addiction affects the brain has used this chemical.
Tabernanthine is an alkaloid found in Tabernanthe iboga.
Thalictrum flavum, known by the common names common meadow-rue, poor man's rhubarb, and yellow meadow-rue, is a flowering plant species in the family Ranunculaceae. It is a native to Caucasus and Russia (Siberia). Growing to 100 cm (39 in) tall by 45 cm (18 in) broad, it is an herbaceous perennial producing clusters of fluffy yellow fragrant flowers in summer.
Synthesis of morphine-like alkaloids in chemistry describes the total synthesis of the natural morphinan class of alkaloids that includes codeine, morphine, oripavine, and thebaine and the closely related semisynthetic analogs methorphan, buprenorphine, hydromorphone, hydrocodone, isocodeine, naltrexone, nalbuphine, oxymorphone, oxycodone, and naloxone.
Akuammicine is a monoterpene indole alkaloid of the Vinca sub-group. It is found in the Apocynaceae family of plants including Picralima nitida, Vinca minor and the Aspidosperma.
Gigactonine is a naturally occurring diterpene alkaloid first isolated from Aconitum gigas. It occurs widely in the Ranunculaceae plant family. The polycyclic ring system of this chemical compound contains nineteen carbon atoms and one nitrogen atom, which is the same as in aconitine and this is reflected in its preferred IUPAC name.
Biomimetic synthesis is an area of organic chemical synthesis that is specifically biologically inspired. The term encompasses both the testing of a "biogenetic hypothesis" through execution of a series of reactions designed to parallel the proposed biosynthesis, as well as programs of study where a synthetic reaction or reactions aimed at a desired synthetic goal are designed to mimic one or more known enzymic transformations of an established biosynthetic pathway. The earliest generally cited example of a biomimetic synthesis is Sir Robert Robinson's organic synthesis of the alkaloid tropinone.
Delsoline and delcosine are two closely related naturally occurring diterpene alkaloids first isolated from Delphinium consolida. They occur widely in the Ranunculaceae plant family. The polycyclic ring system containing nineteen carbon atoms and one nitrogen atom in these compounds is the same as in aconitine and this is reflected in their preferred IUPAC name.
Erysodienone is a key precursor in the biosynthesis of many Erythrina-produced alkaloids. Early work was done by Derek Barton and co-workers to illustrate the biosynthetic pathways towards erythrina alkaloids. It was demonstrated that erysodienone could be synthesized from simple starting materials by a similar approach as its biosynthetic pathway, which led to the development of the biomimetic synthesis of erysodienone.
Tuticorin Raghavachari Govindachari FNA, FASc (1915–2001), popularly known as TRG, was an Indian natural product chemist, academic, institution builder and the principal of Presidency College, Chennai. He was known for his studies on the synthesis of isoquinolines and phenanthridines and his contributions in elucidating the structure of several plant constituents. He was an elected fellow of the Indian Academy of Sciences and the Indian National Science Academy and was the nominator of Robert Burns Woodward who won the 1965 Nobel Prize in Chemistry. The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards, in 1960, for his contributions to chemical sciences, making him the first recipient of the award in the chemical sciences category.
Apparicine is a monoterpenoid indole alkaloid. It is named after Apparicio Duarte, a Brazilian botanist who studied the Aspidosperma species from which apparicine was first isolated. It was the first member of the vallesamine group of alkaloids to be isolated and have its structure established, which was first published in 1965. It has also been known by the synonyms gomezine, pericalline, and tabernoschizine.
Aporphine alkaloids are naturally occurring chemical compounds from the group of alkaloids. After the benzylisoquinoline alkaloids they are the second largest group of isoquinoline alkaloids.
