|
Biginelli Reaction
The Biginelli reaction is a multiple-component chemical reaction that creates 3,4-dihydropyrimidin-2(1''H'')-ones 4 from ethyl acetoacetate 1, an aryl aldehyde (such as benzaldehyde 2), and urea 3. It is named for the Italian chemist Pietro Biginelli.Kappe, C. Oliver (2005) "The Biginelli Reaction", in: J. Zhu and H. Bienaymé (eds.): ''Multicomponent Reactions'', Wiley-VCH, Weinheim, . This reaction was developed by Pietro Biginelli in 1891. The reaction can be catalyzed by Brønsted acids and/or by Lewis acids such as copper(II) trifluoroacetate hydrate and boron trifluoride. Several solid-phase protocols utilizing different linker combinations have been published. Dihydropyrimidinones, the products of the Biginelli reaction, are widely used in the pharmaceutical industry as calcium channel blockers, antihypertensive agents, and alpha-1-a-antagonists. More recently products of the Biginelli reaction have been investigated as potential selective Adenosine A2b receptor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pietro Biginelli
Pietro Biginelli (25 July 1860 – 15 January 1937) was an Italian chemist, who discovered a three-component reaction between urea, acetoacetic ester and aldehydes (Biginelli reaction). He also studied various aspects of sanitation chemistry and chemical products' quality control. Biography Biginelli is born on 25 July 1860 in Palazzolo Vercellese which was back then the Kingdom of Piedmont-Sardinia. He attended the University of Turin, studying under Icilio Guareschi, a well-known Italian chemist and chemistry historian.Istituto Superiore di Sanitа. Microanalisi elementare organica. Collezione di strumenti a cura di Anna Farina e Cecilia Bedetti. 2007, I beni storico-scientifi ci dell’Istituto Superiore di Sanitа, p 24 In 1885, he was already a 4th-year student. By 1891, Biginelli worked at the chemical laboratory at the University of Florence,Biginelli P. Ueber Aldehyduramide des Acetessigaethers. ''Berichte der Deutschen Chemischen Gesellschaft'', 1891, vol. 24, pp. 13 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharmaceutical
A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and relies on the science of pharmacology for continual advancement and on pharmacy for appropriate management. Drugs are classified in multiple ways. One of the key divisions is by level of control, which distinguishes prescription drugs (those that a pharmacist dispenses only on the order of a physician, physician assistant, or qualified nurse) from over-the-counter drugs (those that consumers can order for themselves). Another key distinction is between traditional small molecule drugs, usually derived from chemical synthesis, and biopharmaceuticals, which include recombinant proteins, vaccines, blood products used therapeutically (such as IVIG), gene therapy, monoclonal antibodies and cell therapy (for instance, stem cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condensation Reactions
In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a dehydration synthesis. However other molecules can also be lost, such as ammonia, ethanol, acetic acid and hydrogen sulfide. The addition of the two molecules typically proceeds in a step-wise fashion to the addition product, usually in equilibrium, and with loss of a water molecule (hence the name condensation). The reaction may otherwise involve the functional groups of the molecule, and is a versatile class of reactions that can occur in acidic or basic conditions or in the presence of a catalyst. This class of reactions is a vital part of life as it is essential to the formation of peptide bonds between amino acids and to the biosynthesis of fatty acids. Many variations of condensation reactions exist. Common examples include the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahedron Letters
''Tetrahedron Letters'' is a weekly international journal for rapid publication of full original research papers in the field of organic chemistry. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor of 2.415. Indexing ''Tetrahedron Letters'' is indexed in: References See also *''Tetrahedron In geometry, a tetrahedron (plural: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular faces, six straight edges, and four vertex corners. The tetrahedron is the simplest of all ...'' *'' Tetrahedron: Asymmetry'' Chemistry journals Weekly journals Publications established in 1959 Elsevier academic journals {{chem-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atul Kumar (chemist)
Atul Kumar is a synthetic organic chemist, Professor & Chief Scientist at Academy of Scientific and Innovative Research (AcSIR) and Chairperson Medicinal and Process Chemistry Division Central Drug Research Institute (CSIR-CDRI) at Lucknow, India and a Dean at National Institute of Pharmaceutical Education and Research, Raebareli. Academic work Kumar has about 24 years experience in drug design, medicinal chemistry and Green Chemistry Dr.Kumar's major contributions are invention of Anti- osteoporosis Drug candidate CDRI-99/373 (CENTHANK), which is an currently in phase 1 clinical trial The phases of clinical research are the stages in which scientists conduct experiments with a health intervention to obtain sufficient evidence for a process considered effective as a medical treatment. For drug development, the clinical phases ... and NCE Anti-cancer Compound CDRI-S-007-1235 is currently in Pre-clinical stage. References External links Official website at CDRI Year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterocycles (journal)
''Heterocycles'' is a scientific journal on the topic of heterocyclic compounds. In 2006 it was awarded the "In Memory of Professor A.N. Kost" medal by Lomonosov Moscow State University and Mendeleev Russian Chemical Society. The impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as ... of this journal is 1.079 (2014).Journal Citation Reports, 2015 References Chemistry journals English-language journals Publications established in 1973 {{chemistry-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rate-limiting Step
In chemical kinetics, the overall rate of a reaction is often approximately determined by the slowest step, known as the rate-determining step (RDS or RD-step or r/d step) or rate-limiting step. For a given reaction mechanism, the prediction of the corresponding rate equation (for comparison with the experimental rate law) is often simplified by using this approximation of the rate-determining step. In principle, the time evolution of the reactant and product concentrations can be determined from the set of simultaneous rate equations for the individual steps of the mechanism, one for each step. However, the analytical solution of these differential equations is not always easy, and in some cases numerical integration may even be required. The hypothesis of a single rate-determining step can greatly simplify the mathematics. In the simplest case the initial step is the slowest, and the overall rate is just the rate of the first step. Also, the rate equations for mechanisms with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldol Condensation
An aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties (of aldehydes or ketones) react to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction), and this is then followed by dehydration to give a conjugated enone. The overall reaction is as follows (where the Rs can be H): Aldol condensations are important in organic synthesis and biochemistry as ways to form carbon–carbon bonds. In its usual form, it involves the nucleophilic addition of a ketone enolate to an aldehyde to form a β-hydroxy ketone, or "aldol" (aldehyde + alcohol), a structural unit found in many naturally occurring molecules and pharmaceuticals. The term ''aldol condensation'' is also commonly used, especially in biochemistry, to refer to just the first (addition) stage of the process—the aldol reaction itself—as catalyzed by aldolases. However, this is formally an addition reaction rather than a condensation reaction because it does not inv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
