Elias James Corey is an American organic chemist. In 1990, he won the Nobel Prize in Chemistry "for his development of the theory and methodology of organic synthesis", specifically retrosynthetic analysis. Regarded by many as one of the greatest living chemists, he has developed numerous synthetic reagents, methodologies and total syntheses and has advanced the science of organic synthesis considerably.
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.
Dess–Martin periodinane (DMP) is a chemical reagent used in the Dess–Martin oxidation, oxidizing primary alcohols to aldehydes and secondary alcohols to ketones. This periodinane has several advantages over chromium- and DMSO-based oxidants that include milder conditions, shorter reaction times, higher yields, simplified workups, high chemoselectivity, tolerance of sensitive functional groups, and a long shelf life. However, use on an industrial scale is made difficult by its cost and its potentially explosive nature. It is named after the American chemists Daniel Benjamin Dess and James Cullen Martin who developed the reagent in 1983. It is based on IBX, but due to the acetate groups attached to the central iodine atom, DMP is much more reactive than IBX and is much more soluble in organic solvents.
Cavicularin is a natural phenolic secondary metabolite isolated from the liverwort Cavicularia densa. This macrocycle is unusual because it was the first compound isolated from nature displaying optical activity solely due to the presence of planar chirality and axial chirality. The specific rotation for (+)-cavicularin is +168.2°. It is also a very strained molecule. The para-substituted phenol ring is bent about 15° out of planarity, adopting a somewhat boat-like geometry. This type of angle strain in aromatic compounds is normally reserved for synthetic cyclophanes.
Okadaic acid, C44H68O13, is a toxin produced by several species of dinoflagellates, and is known to accumulate in both marine sponges and shellfish. One of the primary causes of diarrhetic shellfish poisoning, okadaic acid is a potent inhibitor of specific protein phosphatases and is known to have a variety of negative effects on cells. A polyketide, polyether derivative of a C38 fatty acid, okadaic acid and other members of its family have shined light upon many biological processes both with respect to dinoflagellete polyketide synthesis as well as the role of protein phosphatases in cell growth.
Phorbol is a natural, plant-derived organic compound. It is a member of the tigliane family of diterpenes. Phorbol was first isolated in 1934 as the hydrolysis product of croton oil, which is derived from the seeds of the purging croton, Croton tiglium. The structure of phorbol was determined in 1967. Various esters of phorbol have important biological properties, the most notable of which is the capacity to act as tumor promoters through activation of protein kinase C. They mimic diacylglycerols, glycerol derivatives in which two hydroxyl groups have reacted with fatty acids to form esters. The most common and potent phorbol ester is 12-O-tetradecanoylphorbol-13-acetate (TPA), also called phorbol-12-myristate-13-acetate (PMA), which is used as a biomedical research tool in contexts such as models of carcinogenesis.
3,3′,5,5′-Tetramethylbenzidine or TMB is a chromogenic substrate used in staining procedures in immunohistochemistry as well as being a visualising reagent used in enzyme-linked immunosorbent assays (ELISA). TMB is a white solid that forms a pale blue-green liquid in solution with ethyl acetate. TMB is degraded by sunlight and by fluorescent lights.
Swainsonine is an indolizidine alkaloid. It is a potent inhibitor of Golgi alpha-mannosidase II, an immunomodulator, and a potential chemotherapy drug. As a toxin in locoweed it also is a significant cause of economic losses in livestock industries, particularly in North America. It was first isolated from Swainsona canescens.
The Woodward cis-hydroxylation is the chemical reaction of alkenes with iodine and silver acetate in wet acetic acid to form cis-diols.(conversion of olefin into cis-diol)
Nucleoside phosphoramidites are derivatives of natural or synthetic nucleosides. They are used to synthesize oligonucleotides, relatively short fragments of nucleic acid and their analogs. Nucleoside phosphoramidites were first introduced in 1981 by Beaucage and Caruthers. To avoid undesired side reactions, reactive hydroxy and exocyclic amino groups present in natural or synthetic nucleosides are appropriately protected. As long as a nucleoside analog contains at least one hydroxy group, the use of the appropriate protecting strategy allows one to convert that to the respective phosphoramidite and to incorporate the latter into synthetic nucleic acids. To be incorporated in the middle of an oligonucleotide chain using phosphoramidite strategy, the nucleoside analog must possess two hydroxy groups or, less often, a hydroxy group and another nucleophilic group (amino or mercapto). Examples include, but are not limited to, alternative nucleotides, LNA, morpholino, nucleosides modified at the 2'-position (OMe, protected NH2, F), nucleosides containing non-canonical bases (hypoxanthine and xanthine contained in natural nucleosides inosine and xanthosine, respectively, tricyclic bases such as G-clamp, etc.) or bases derivatized with a fluorescent group or a linker arm.
Oligonucleotide synthesis is the chemical synthesis of relatively short fragments of nucleic acids with defined chemical structure (sequence). The technique is extremely useful in current laboratory practice because it provides a rapid and inexpensive access to custom-made oligonucleotides of the desired sequence. Whereas enzymes synthesize DNA and RNA only in a 5' to 3' direction, chemical oligonucleotide synthesis does not have this limitation, although it is most often carried out in the opposite, 3' to 5' direction. Currently, the process is implemented as solid-phase synthesis using phosphoramidite method and phosphoramidite building blocks derived from protected 2'-deoxynucleosides, ribonucleosides, or chemically modified nucleosides, e.g. LNA or BNA.
Ptaquiloside is a norsesquiterpene glucoside produced by bracken ferns during metabolism. It is identified to be the main carcinogen of the ferns and to be responsible for their biological effects, such as haemorrhagic disease and bright blindness in livestock and oesophageal, gastric cancer in humans. Ptaquiloside has unstable chemical structure and acts as a DNA alkylating agent under physiological conditions. It was first isolated and characterized by Yamada and co-workers in 1983.
Nitrile anions is jargon from the organic product resulting from the deprotonation of alkylnitriles. The proton(s) α to the nitrile group are sufficiently acidic that they undergo deprotonation by strong bases, usually lithium-derived. The products are not anions but covalent organolithium complexes. Regardless, these organolithium compounds are reactive toward various electrophiles.
Taxodone is a naturally occurring diterpenoid found in Taxodium distichum, Rosmarinus officinalis (rosemary), several salvia species and other plants, along with its oxidized rearrangement product, taxodione. Taxodone and taxodione exhibit anticancer, antibacterial, antioxidant, antifungal, insecticide, and antifeedant activities.
Aniba megaphylla is a species of tree in the family Lauraceae and is native to South America. It is native to Bolivia, Brazil North, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, and Venezuela, growing primarily in wet tropical biomes. This species produces the cytotoxic lignan megaphone.
Capnellene is a naturally occurring tricyclic hydrocarbon derived from Capnella imbricata, a species of soft coral found in Indonesia. Since the 1970s, capnellene has been targeted for synthesis by numerous investigators due to its stereochemistry, functionality, and the interesting geometry of the carbon skeleton. Many alcohol derivatives of capnellene have demonstrated potential as a chemotherapeutic agent with antibacterial, anti-inflammatory and anti-tumor properties.
Callystatin A is a polyketide natural product from the leptomycin family of secondary metabolites. It was first isolated in 1997 from the marine sponge Callyspongia truncata which was collected from the Goto Islands in the Nagasaki Prefecture of Japan by the Kobayashi group. Since then its absolute configuration has been elucidated and callystatin A was discovered to have anti-fungal and anti-tumor activities with extreme potency against the human epidermoid carcinoma KB cells (IG50 = 10 pg/ml) and the mouse lymphocytic leukemia Ll210 cells (IG50 = 20 pg/ml).
Lavendamycin is a naturally occurring chemical compound discovered in fermentation broth of the soil bacterium Streptomyces lavendulae. Lavendamycin has antibiotic properties and anti-proliferative effects against several cancer cell lines. The use of lavendamycin as a cytotoxic agent in cancer therapy failed due to poor water solubility and non-specific cytotoxicity. The study of lavendamycin-based analogs designed to overcome these liabilities has been an area of research.
The Chan–Lam coupling reaction – also known as the Chan–Evans–Lam coupling is a cross-coupling reaction between an aryl boronic acid and an alcohol or an amine to form the corresponding secondary aryl amines or aryl ethers, respectively. The Chan–Lam coupling is catalyzed by copper complexes. It can be conducted in air at room temperature. The more popular Buchwald–Hartwig coupling relies on the use of palladium.
1,3-Diphenylisobenzofuran is a highly reactive diene that can scavenge unstable and short-lived dienophiles in a Diels-Alder reaction. It is furthermore used as a standard reagent for the determination of singlet oxygen, even in biological systems. Cycloadditions with 1,3-diphenylisobenzofuran and subsequent oxygen cleavage provide access to a variety of polyaromatics.
