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Aspidophytine
Aspidophytine is an indole alkaloid that has attracted significant attention from synthetic chemists.''"A Concise Asymmetric Total Synthesis of Aspidophytine" ''Nicolaou, K. C., Dalby, S. M., Majumder, U. ''J. Am. Chem. Soc.'' 2008, ''130(45)'', 14942–14943 () An extract of the cockroach plant, aspidophytine is an insecticidal substance particularly effective against cockroaches. It is one of the two components of the dimer haplophytine.Column: Totally Synthetic by Paul Docherty, at the ; published October 9, 2009; retrieved October 3, 2014 In his suicide note, Harvard doctoral student [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jason Altom
Jason Altom (6 October 1971 – 15 August 1998) was an American PhD student working in the research group of Nobel laureate Elias James Corey at Harvard University. He died by suicide in 1998 by ingesting potassium cyanide, citing "abusive research supervisors" in his suicide note as one reason for taking his life. Altom was studying a complex natural product and experienced significant pressure to complete the molecule before starting his academic career. Altom's suicide highlighted the pressures on PhD students, problems of isolation in graduate school, and sources of tension between graduate mentors and their students. His case prompted many US universities to insist that PhD students have an advisory committee in addition to a supervisor, to whom they might turn for support: James Anderson, who became Harvard Chemistry Department Chairman, stated that "Jason's death prompted an examination of the role the department should play in graduate students' lives". Anderson went on to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indole
Indole is an organic compound with the formula . Indole is classified as an aromatic heterocycle. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered pyrrole ring. Indoles are derivatives of indole where one or more of the hydrogen atoms have been replaced by substituent groups. Indoles are widely distributed in nature, most notably as amino acid tryptophan and neurotransmitter serotonin. General properties and occurrence Indole is a solid at room temperature. It occurs naturally in human feces and has an intense fecal odor. At very low concentrations, however, it has a flowery smell, and is a constituent of many perfumes. It also occurs in coal tar. It has been identified in cannabis. It is the main volatile compound in stinky tofu. When indole is a substituent on a larger molecule, it is called an ''indolyl group'' by systematic nomenclature. Indole undergoes electrophilic substitution, mainly at position 3 (see diagram in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkaloid
Alkaloids are a broad class of natural product, naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids. Alkaloids are produced by a large variety of organisms including bacteria, fungus, fungi, Medicinal plant, plants, and animals. They can be purified from crude extracts of these organisms by acid-base extraction, or solvent extractions followed by silica-gel column chromatography. Alkaloids have a wide range of pharmacology, pharmacological activities including antimalarial medication, antimalarial (e.g. quinine), asthma, antiasthma (e.g. ephedrine), chemotherapy, anticancer (e.g. omacetaxine mepesuccinate, homoharringtonine), cholinomimetic (e.g. galantamine), vasodilation, vasodilatory (e.g. vincamine), Antiarrhythmic agent, antiarrhythmic (e.g. quinidine), analgesic (e.g. morphine), antibacterial (e.g. chelerythrine), and anti-diabetic, antihyperglycemic activities (e.g. berb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cockroach Plant
''Haplophyton crooksii'' is a plant species native to Arizona, New Mexico, Texas, and northern Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar .... It is an herb up to 60 cm tall, with showy yellow flowers, found on rocky slopes in desert scrub and desert grassland.L.D. Benson. 1943. American Journal of Botany 30(8): 630. 1943.McLaughliln, S.P. 1993. Apocynaceae A.L. Juss., Dogbane Family. Journal of the Arizona-Nevada Academy of Science 27:164-168. The plant is commonly called the cockroach plant (or ''hierba de la cucaracha'') because of its insecticidal properties. References Rauvolfioideae Flora of Chihuahua (state) Flora of Sonora Flora of Mexico Flora of New Mexico Flora of Arizona Flora of Texas {{Apocynaceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insecticide
Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, industrial buildings, for vector control, and control of insect parasites of animals and humans. Acaricides, which kill mites and ticks, are not strictly insecticides, but are usually classified together with insecticides. Some insecticides (including common bug sprays) are effective against other non-insect arthropods as well, such as scorpions, spiders, etc. Insecticides are distinct from insect repellents, which repel but do not kill. Sales In 2016 insecticides were estimated to account for 18% of worldwide pesticide sales. Worldwide sales of insecticides in 2018 were estimated as $ 18.4 billion, of which 25% were neonicotinoids, 17% were pyrethroids, 13% were diamides, and the rest were many other classes which sold for less th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cockroach
Cockroaches (or roaches) are insects belonging to the Order (biology), order Blattodea (Blattaria). About 30 cockroach species out of 4,600 are associated with human habitats. Some species are well-known Pest (organism), pests. Modern cockroaches are an ancient group that first appeared during the Late Jurassic, with their ancestors, known as "Roachoid, roachoids", likely originating during the Carboniferous period around 320 million years ago. Those early ancestors, however, lacked the internal ovipositors of modern roaches. Cockroaches are somewhat generalized insects lacking special adaptations (such as the sucking Insect mouthparts, mouthparts of aphids and other Hemiptera, true bugs); they have chewing mouthparts and are probably among the most primitive of living Neopteran insects. They are common and hardy insects capable of tolerating a wide range of Köppen climate classification, climates, from Arctic cold to Tropics, tropical heat. Tropical cockroaches are often muc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimer (chemistry)
In chemistry, dimerization is the process of joining two identical or similar Molecular entity, molecular entities by Chemical bond, bonds. The resulting bonds can be either strong or weak. Many symmetrical chemical species are described as dimers, even when the monomer is unknown or highly unstable. The term ''homodimer'' is used when the two subunits are identical (e.g. A–A) and ''heterodimer'' when they are not (e.g. A–B). The reverse of dimerization is often called Dissociation (chemistry), dissociation. When two oppositely-charged ions associate into dimers, they are referred to as ''Bjerrum pairs'', after Danish chemist Niels Bjerrum. Noncovalent dimers Anhydrous carboxylic acids form dimers by hydrogen bonding of the acidic hydrogen and the carbonyl oxygen. For example, acetic acid forms a dimer in the gas phase, where the monomer units are held together by hydrogen bonds. Many OH-containing molecules form dimers, e.g. the water dimer. Dimers that form based on w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society and professional association in the United Kingdom with the goal of "advancing the chemistry, chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 49,000 in the world. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham (chemist), Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing and Shanghai, People' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The New York Times
''The New York Times'' (''NYT'') is an American daily newspaper based in New York City. ''The New York Times'' covers domestic, national, and international news, and publishes opinion pieces, investigative reports, and reviews. As one of the longest-running newspapers in the United States, the ''Times'' serves as one of the country's Newspaper of record, newspapers of record. , ''The New York Times'' had 9.13 million total and 8.83 million online subscribers, both by significant margins the List of newspapers in the United States, highest numbers for any newspaper in the United States; the total also included 296,330 print subscribers, making the ''Times'' the second-largest newspaper by print circulation in the United States, following ''The Wall Street Journal'', also based in New York City. ''The New York Times'' is published by the New York Times Company; since 1896, the company has been chaired by the Ochs-Sulzberger family, whose current chairman and the paper's publ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tryptamine Alkaloids
Tryptamine is an indolamine metabolite of the essential amino acid tryptophan. The chemical structure is defined by an indole—a fused benzene and pyrrole ring, and a 2-aminoethyl group at the second carbon (third aromatic atom, with the first one being the heterocyclic nitrogen). The structure of tryptamine is a shared feature of certain aminergic neuromodulators including melatonin, serotonin, bufotenin and psychedelic derivatives such as dimethyltryptamine (DMT), psilocybin, psilocin and others. Tryptamine has been shown to activate serotonin receptors and trace amine-associated receptors expressed in the mammalian brain, and regulates the activity of dopaminergic, serotonergic and glutamatergic systems. In the human gut, bacteria convert dietary tryptophan to tryptamine, which activates 5-HT4 receptors and regulates gastrointestinal motility. Multiple tryptamine-derived drugs have been developed to treat migraines, while trace amine-associated receptors are being ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkaloids Found In Apocynaceae
Alkaloids are a broad class of natural product, naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids. Alkaloids are produced by a large variety of organisms including bacteria, fungus, fungi, Medicinal plant, plants, and animals. They can be purified from crude extracts of these organisms by acid-base extraction, or solvent extractions followed by silica-gel column chromatography. Alkaloids have a wide range of pharmacology, pharmacological activities including antimalarial medication, antimalarial (e.g. quinine), asthma, antiasthma (e.g. ephedrine), chemotherapy, anticancer (e.g. omacetaxine mepesuccinate, homoharringtonine), cholinomimetic (e.g. galantamine), vasodilation, vasodilatory (e.g. vincamine), Antiarrhythmic agent, antiarrhythmic (e.g. quinidine), analgesic (e.g. morphine), antibacterial (e.g. chelerythrine), and anti-diabetic, antihyperglycemic activities (e.g. berb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lactones
Lactones are cyclic carboxylic esters. They are derived from the corresponding hydroxycarboxylic acids by esterification. They can be saturated or unsaturated. Lactones are formed by lactonization, the intramolecular esterification of the corresponding hydroxycarboxylic acids. Nomenclature Greek prefixes in alphabetical order indicate ring size. Lactones are usually named according to the precursor acid molecule (''aceto'' = 2 carbon atoms, ''propio'' = 3, ''butyro'' = 4, ''valero'' = 5, ''capro'' = 6, etc.), with a ''-lactone'' suffix and a Greek letter prefix that specifies the number of carbon atoms in the heterocycle — that is, the distance between the relevant -OH and the -COOH groups along said backbone. The first carbon atom after the carbon in the -COOH group on the parent compound is labelled α, the second will be labeled β, and so forth. Therefore, the prefixes also indicate the size of the lactone ring: α-lactone = 3-membered ring, β-lactone = 4-membered, γ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
