In organic chemistry, allenes are organic compounds in which one carbon atom has double bonds with each of its two adjacent carbon atoms. Allenes are classified as cumulated dienes. The parent compound of this class is propadiene, which is itself also called allene. An group of the structure R2C=C=CR− is called allenyl, where R is H or some alkyl group. Compounds with an allene-type structure but with more than three carbon atoms are members of a larger class of compounds called cumulenes with X=C=Y bonding.
A beta-lactam (β-lactam) ring is a four-membered lactam. A lactam is a cyclic amide, and beta-lactams are named so because the nitrogen atom is attached to the β-carbon atom relative to the carbonyl. The simplest β-lactam possible is 2-azetidinone. β-lactams are significant structural units of medicines as manifested in many β-lactam antibiotics Up to 1970, most β-lactam research was concerned with the penicillin and cephalosporin groups, but since then, a wide variety of structures have been described.
Salvinorin A is the main active psychotropic molecule in Salvia divinorum. Salvinorin A is considered a dissociative hallucinogen.
Total synthesis is the complete chemical synthesis of a complex molecule, often a natural product, from simple, commercially-available precursors. It usually refers to a process not involving the aid of biological processes, which distinguishes it from semisynthesis. Syntheses may sometimes conclude at a precursor with further known synthetic pathways to a target molecule, in which case it is known as a formal synthesis. Total synthesis target molecules can be natural products, medicinally-important active ingredients, known intermediates, or molecules of theoretical interest. Total synthesis targets can also be organometallic or inorganic, though these are rarely encountered. Total synthesis projects often require a wide diversity of reactions and reagents, and subsequently requires broad chemical knowledge and training to be successful.
A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical synthesis and have played a central role in the development of the field of organic chemistry by providing challenging synthetic targets. The term natural product has also been extended for commercial purposes to refer to cosmetics, dietary supplements, and foods produced from natural sources without added artificial ingredients.
In organic chemistry, benzyl is the substituent or molecular fragment possessing the structure R−CH2−C6H5. Benzyl features a benzene ring attached to a methylene group group.
In organic chemistry, the Ugi reaction is a multi-component reaction involving a ketone or aldehyde, an amine, an isocyanide and a carboxylic acid to form a bis-amide. The reaction is named after Ivar Karl Ugi, who first reported this reaction in 1959.
Ionomycin is an ionophore and an antibiotic that binds calcium ions (Ca2+) in a ratio 1:1. It is produced by the bacterium Streptomyces conglobatus. It binds also other divalent cations like magnesium and cadmium, but binds Ca2+ preferably.
The Weinreb–Nahm ketone synthesis is a chemical reaction used in organic chemistry to make carbon–carbon bonds. It was discovered in 1981 by Steven M. Weinreb and Steven Nahm as a method to synthesize ketones. The original reaction involved two subsequent nucleophilic acyl substitutions: the conversion of an acid chloride with N,O-Dimethylhydroxylamine, to form a Weinreb–Nahm amide, and subsequent treatment of this species with an organometallic reagent such as a Grignard reagent or organolithium reagent. Nahm and Weinreb also reported the synthesis of aldehydes by reduction of the amide with an excess of lithium aluminum hydride.
The Negishi coupling is a widely employed transition metal catalyzed cross-coupling reaction. The reaction couples organic halides or triflates with organozinc compounds, forming carbon-carbon bonds (C-C) in the process. A palladium (0) species is generally utilized as the metal catalyst, though nickel is sometimes used. A variety of nickel catalysts in either Ni0 or NiII oxidation state can be employed in Negishi cross couplings such as Ni(PPh3)4, Ni(acac)2, Ni(COD)2 etc.
Pericine is one of a number of indole alkaloids found in the tree Picralima nitida, commonly known as akuamma. As with some other alkaloids from this plant such as akuammine, pericine has been shown to bind to mu opioid receptors in vitro, and has an IC50 of 0.6 μmol, within the range of a weak analgesic. It may also have convulsant effects.
Hexacyclinol is a natural metabolite of a fungus, Panus rudis. Significant controversy surrounded its proposed structure until its total synthesis by John Porco, Jr. in 2006.
The Saegusa–Ito oxidation is a chemical reaction used in organic chemistry. It was discovered in 1978 by Takeo Saegusa and Yoshihiko Ito as a method to introduce α-β unsaturation in carbonyl compounds. The reaction as originally reported involved formation of a silyl enol ether followed by treatment with palladium(II) acetate and benzoquinone to yield the corresponding enone. The original publication noted its utility for regeneration of unsaturation following 1,4-addition with nucleophiles such as organocuprates.
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.
Viridicatumtoxin B is a fungus-derived tetracycline-like antibiotic discovered in 2008. It was isolated from small amounts of penicillium fungi. A synthetic structure matching that of natural viridicatumtoxin B makes possible synthetic variants that match or surpass its antibiotic potency.
Lactimidomycin is a glutarimide antibiotic derived from the bacteria Streptomyces amphibiosporus. It has antifungal, antiviral and anti-cancer properties, acting as a direct inhibitor of protein translation in ribosomes. Antiviral activity is seen against a variety of RNA viruses including flaviviruses such as dengue fever, Kunjin virus and Modoc virus, as well as vesicular stomatitis virus and poliovirus. As lactimidomycin is a natural product containing an unusual unsaturated 12-membered lactone ring, it has been the subject of numerous total synthesis approaches.
Streptomyces prunicolor is a bacterium species from the genus of Streptomyces which has been isolated from soil in Russia. Streptomyces prunicolor produces Pironetin and the free radical scavengers benthocyanin A, benthocyanin B and benthocyanin C.
The Cadogan–Sundberg indole synthesis, or simply Cadogan indole synthesis, is a name reaction in organic chemistry that allows for the generation of indoles from o-nitrostyrenes with the use of trialkyl phosphites, such as triethyl phosphite.
Frenolicin B is an antibiotic and antitumor agent with the molecular formula C18H16O6 which is produced by the bacterium Streptomyces roseofulvus. Frenolicin B is a selective inhibitor of glutaredoxin 3 and peroxiredoxin 1.
Aigialomycin D is a macrolide antibiotic which is produced by the fungi Aigialus parvus. Aigialomycin D is a resorcylic acid lactone and has the molecular formula C18H22O6. Preliminary studies found that aigialomycin D is a protein kinase inhibitor with anti-tumor activity. Aigialomycin D has antimalarial activity.
