Cyclobutane is a cycloalkane and organic compound with the formula (CH2)4. Cyclobutane is a colourless gas and is commercially available as a liquefied gas. Derivatives of cyclobutane are called cyclobutanes. Cyclobutane itself is of no commercial or biological significance, but more complex derivatives are important in biology and biotechnology.
In chemistry, a molecule or ion is called chiral if it cannot be superposed on its mirror image by any combination of rotations, translations, and some conformational changes. This geometric property is called chirality. The terms are derived from Ancient Greek χείρ (cheir) 'hand'; which is the canonical example of an object with this property.
BINAP (2,2′-bis(diphenylphosphino)-1,1′-binaphthyl) is an organophosphorus compound. This chiral diphosphine ligand is widely used in asymmetric synthesis. It consists of a pair of 2-diphenylphosphinonaphthyl groups linked at the 1 and 1′ positions. This C2-symmetric framework lacks a stereogenic atom, but has axial chirality due to restricted rotation (atropisomerism). The barrier to racemization is high due to steric hindrance, which limits rotation about the bond linking the naphthyl rings. The dihedral angle between the naphthyl groups is approximately 90°. The natural bite angle is 93°.
1,1′-Bi-2-naphthol (BINOL) is an organic compound that is often used as a ligand for transition-metal catalysed asymmetric synthesis. BINOL has axial chirality and the two enantiomers can be readily separated and are stable toward racemisation. The specific rotation of the two enantiomers is 35.5° (c = 1 in THF), with the R enantiomer being the dextrorotary one. BINOL is a precursor for another chiral ligand called BINAP. The volumetric mass density of the two enantiomers is 0.62 g cm−3.
Atropisomers are stereoisomers arising because of hindered rotation about a single bond, where energy differences due to steric strain or other contributors create a barrier to rotation that is high enough to allow for isolation of individual conformers. They occur naturally and are important in pharmaceutical design. When the substituents are achiral, these conformers are enantiomers (atropoenantiomers), showing axial chirality; otherwise they are diastereomers (atropodiastereomers).
Trifluoromethanesulfonic anhydride, also known as triflic anhydride, is the chemical compound with the formula (CF3SO2)2O. It is the acid anhydride derived from triflic acid. This compound is a strong electrophile, useful for introducing the triflyl group, CF3SO2. Abbreviated Tf2O, triflic anhydride is the acid anhydride of the superacid triflic acid, CF3SO2OH.
In analytical chemistry, a chiral derivatizing agent (CDA), also known as a chiral resolving reagent, is a derivatization reagent that is a chiral auxiliary used to convert a mixture of enantiomers into diastereomers in order to analyze the quantities of each enantiomer present and determine the optical purity of a sample. Analysis can be conducted by spectroscopy or by chromatography. Some analytical techniques such as HPLC and NMR, in their most commons forms, cannot distinguish enantiomers within a sample, but can distinguish diastereomers. Therefore, converting a mixture of enantiomers to a corresponding mixture of diastereomers can allow analysis. The use of chiral derivatizing agents has declined with the popularization of chiral HPLC. Besides analysis, chiral derivatization is also used for chiral resolution, the actual physical separation of the enantiomers.
Chiral resolution, or enantiomeric resolution, is a process in stereochemistry for the separation of racemic mixture into their enantiomers. It is an important tool in the production of optically active compounds, including drugs. Another term with the same meaning is optical resolution.
NOBIN (2-amino-2'-hydroxy-1,1'-binaphthyl) is an organic molecule used for asymmetric catalysis. NOBIN is related to BINOL and other analogs by both having a chiral axis and being a scaffold for certain chemical reactions. NOBIN is an excellent catalyst for the aldol reaction producing reliable products, good yields, and excellent diastereoselectivity.
2β-Propanoyl-3β-(2-naphthyl)-tropane or WF-23 is a cocaine analogue. It is several hundred times more potent than cocaine at being a serotonin-norepinephrine-dopamine reuptake inhibitor.
N,O-Dimethyl-4β-(2-naphthyl)piperidine-3β-carboxylate (DMNPC) is a piperidine based stimulant drug which is synthesised from arecoline. It is similar to nocaine in chemical structure, and has two and a half times more activity than cocaine as a dopamine reuptake inhibitor. However it is also a potent serotonin reuptake inhibitor, with similar affinity to fluoxetine.
1,1-Bis(diphenylphosphino)methane (dppm), is an organophosphorus compound with the formula CH2(PPh2)2. Dppm, a white, crystalline powder, is used in inorganic and organometallic chemistry as a ligand. It is more specifically a chelating ligand because it is a ligand that can bond to metals with two phosphorus donor atoms. The natural bite angle is 73°.
Pirkle's alcohol is an off-white, crystalline solid that is stable at room temperature when protected from light and oxygen. This chiral molecule is typically used, in nonracemic form, as a chiral shift reagent in nuclear magnetic resonance spectroscopy, in order to simultaneously determine absolute configuration and enantiomeric purity of other chiral molecules. The molecule is named after William H. Pirkle, Professor of Chemistry at the University of Illinois whose group reported its synthesis and its application as a chiral shift reagent.
The molecular formula C20H14 (molar mass: 254.32 g/mol, exact mass: 254.1096 u) may refer to:
Procyanidin B1 is a procyanidin dimer.
Procyanidin A1 is an A type proanthocyanidin dimer.
Cannabicyclohexanol is a cannabinoid receptor agonist drug, developed by Pfizer in 1979. On 19 January 2009, the University of Freiburg in Germany announced that an analog of CP 47,497 was the main active ingredient in the herbal incense product Spice, specifically the 1,1-dimethyloctyl homologue of CP 47,497, which is now known as cannabicyclohexanol. The 1,1-dimethyloctyl homologue of CP 47,497 is in fact several times more potent than the parent compound, which is somewhat unexpected as the 1,1-dimethylheptyl is the most potent substituent in classical cannabinoid compounds such as HU-210.
JWH-164 is a synthetic cannabinoid receptor agonist from the naphthoylindole family. It has approximately equal affinity for the CB1 and CB2 receptors, with a Ki of 6.6 nM at CB1 and 6.9 nM at CB2. JWH-164 is a positional isomer of the related compound JWH-081, but with a methoxy group at the 7-position of the naphthyl ring, rather than the 4-position as in JWH-081. Its potency is intermediate between that of JWH-081 and its ring unsubstituted derivative JWH-018, demonstrating that substitution of the naphthyl 7-position can also result in increased cannabinoid receptor binding affinity.
Chadwick Alma Tolman was an American chemist. He obtained his B.S. in Chemistry from Massachusetts Institute of Technology. He earned his Ph.D. in Chemistry as a microwave spectroscopist from U.C. Berkeley under the guidance of William Dulaney Gwinn.
The phomoxanthones are a loosely defined class of natural products. The two founding members of this class are phomoxanthone A and phomoxanthone B. Other compounds were later also classified as phomoxanthones, although a unifying nomenclature has not yet been established. The structure of all phomoxanthones is derived from a dimer of two covalently linked tetrahydroxanthones, and they differ mainly in the position of this link as well as in the acetylation status of their hydroxy groups. The phomoxanthones are structurally closely related to other tetrahydroxanthone dimers such as the secalonic acids and the eumitrins. While most phomoxanthones were discovered in fungi of the genus Phomopsis, most notably in the species Phomopsis longicolla, some have also been found in Penicillium sp.
