An ester is a chemical compound derived from an acid in which at least one –OH hydroxyl group is replaced by an –O– alkyl (alkoxy) group, as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils.
Proline (symbol Pro or P) is an organic acid classed as a proteinogenic amino acid (used in the biosynthesis of proteins), although it does not contain the amino group -NH
2 but is rather a secondary amine. The secondary amine nitrogen is in the protonated NH2+ form under biological conditions, while the carboxyl group is in the deprotonated −COO− form. The "side chain" from the α carbon connects to the nitrogen forming a pyrrolidine loop, classifying it as a aliphatic amino acid. It is non-essential in humans, meaning the body can synthesize it from the non-essential amino acid L-glutamate. It is encoded by all the codons starting with CC (CCU, CCC, CCA, and CCG).
Pyrrole is a heterocyclic aromatic organic compound, a five-membered ring with the formula C4H4NH. It is a colorless volatile liquid that darkens readily upon exposure to air. Substituted derivatives are also called pyrroles, e.g., N-methylpyrrole, C4H4NCH3. Porphobilinogen, a trisubstituted pyrrole, is the biosynthetic precursor to many natural products such as heme.
In chemistry thioesters are compounds with the functional group R–S–CO–R'. They are analogous to carboxylate esters with the sulfur in the thioester playing the role of the linking oxygen in the carboxylate ester. They are the product of esterification between a carboxylic acid and a thiol. In biochemistry, the best-known thioesters are derivatives of coenzyme A, e.g., acetyl-CoA.
An enamine is an unsaturated compound derived by the condensation of an aldehyde or ketone with a secondary amine. Enamines are versatile intermediates.
Ethyl acetate is the organic compound with the formula CH3−COO−CH2−CH3, simplified to C4H8O2. This colorless liquid has a characteristic sweet smell and is used in glues, nail polish removers, and in the decaffeination process of tea and coffee. Ethyl acetate is the ester of ethanol and acetic acid; it is manufactured on a large scale for use as a solvent.
Methyl acetate, also known as MeOAc, acetic acid methyl ester or methyl ethanoate, is a carboxylate ester with the formula CH3COOCH3. It is a flammable liquid with a characteristically pleasant smell reminiscent of some glues and nail polish removers. Methyl acetate is occasionally used as a solvent, being weakly polar and lipophilic, but its close relative ethyl acetate is a more common solvent being less toxic and less soluble in water. Methyl acetate has a solubility of 25% in water at room temperature. At elevated temperature its solubility in water is much higher. Methyl acetate is not stable in the presence of strong aqueous bases or aqueous acids. Methyl acetate is not considered a VOC in the USA.
The Michael reaction or Michael addition is the nucleophilic addition of a carbanion or another nucleophile to an α,β-unsaturated carbonyl compound containing an electron withdrawing group. It belongs to the larger class of conjugate additions. This is one of the most useful methods for the mild formation of C–C bonds. Many asymmetric variants exist.
The Robinson annulation is a chemical reaction used in organic chemistry for ring formation. It was discovered by Robert Robinson in 1935 as a method to create a six membered ring by forming three new carbon–carbon bonds. The method uses a ketone and a methyl vinyl ketone to form an α,β-unsaturated ketone in a cyclohexane ring by a Michael addition followed by an aldol condensation. This procedure is one of the key methods to form fused ring systems.
The Mannich reaction is an organic reaction which consists of an amino alkylation of an acidic proton placed next to a carbonyl functional group by formaldehyde and a primary or secondary amine or ammonia. The final product is a β-amino-carbonyl compound also known as a Mannich base. Reactions between aldimines and α-methylene carbonyls are also considered Mannich reactions because these imines form between amines and aldehydes. The reaction is named after chemist Carl Mannich.
The Controlled Drugs and Substances Act is Canada's federal drug control statute. Passed in 1996 under Prime Minister Jean Chrétien's government, it repeals the Narcotic Control Act and Parts III and IV of the Food and Drugs Act, and establishes eight Schedules of controlled substances and two Classes of precursors. It provides that "The Governor in Council may, by order, amend any of Schedules I to VIII by adding to them or deleting from them any item or portion of an item, where the Governor in Council deems the amendment to be necessary in the public interest."
A formylation reaction in organic chemistry refers to organic reactions in which an organic compound is functionalized with a formyl group (-CH=O). The reaction is a route to aldehydes (C-CH=O), formamides (N-CH=O), and formate esters (O-CH=O). A reagent that delivers the formyl group is called a formylating agent. A particularly important formylation process is hydroformylation which converts alkenes to the homologated aldehyde. The conversion of benzene to benzaldehyde is the basis of the Gattermann–Koch reaction:
The Knorr pyrrole synthesis is a widely used chemical reaction that synthesizes substituted pyrroles (3). The method involves the reaction of an α-amino-ketone (1) and a compound containing an electron-withdrawing group α to a carbonyl group (2).
The organic compound ethyl acetoacetate (EAA) is the ethyl ester of acetoacetic acid. It is a colorless liquid. It is widely used as a chemical intermediate in the production of a wide variety of compounds. It is used as a flavoring for food.
The Hajos–Parrish–Eder–Sauer–Wiechert reaction in organic chemistry is a proline catalysed asymmetric aldol reaction. The reaction is named after its principal investigators, Zoltan Hajos others, from Hoffmann-La Roche and Schering AG. Discovered in the 1970s the original Hajos-Parrish catalytic procedure – shown in the reaction equation, leading to the optically active bicyclic ketol – paved the way of asymmetric organocatalysis. The Eder-Sauer-Wiechert modification lead directly to the optically active enedione, through the loss of water from the bicyclic ketol shown in figure.
1-Pyrroline-5-carboxylic acid is a cyclic imino acid. Its conjugate base and anion is 1-pyrroline-5-carboxylate (P5C). In solution, P5C is in spontaneous equilibrium with glutamate-5-semialdhyde (GSA). The stereoisomer (S)-1-pyrroline-5-carboxylate is an intermediate metabolite in the biosynthesis and degradation of proline and arginine.
N-Sulfinyl imines are a class of imines bearing a sulfinyl group attached to nitrogen. These imines display usefully stereoselectivity reactivity and due to the presence of the chiral electron withdrawing N-sulfinyl group. They allow 1,2-addition of organometallic reagents to imines. The N-sulfinyl group exerts powerful and predictable stereodirecting effects resulting in high levels of asymmetric induction. Racemization of the newly created carbon-nitrogen stereo center is prevented because anions are stabilized at nitrogen. The sulfinyl chiral auxiliary is readily removed by simple acid hydrolysis. The addition of organometallic reagents to N-sulfinyl imines is the most reliable and versatile method for the asymmetric synthesis of amine derivatives. These building blocks have been employed in the asymmetric synthesis of numerous biologically active compounds.
Pyrrole-2-carboxylate decarboxylase (EC 4.1.1.93) is an enzyme with systematic name pyrrole-2-carboxylate carboxy-lyase. This enzyme catalyses the following chemical reaction
Ethyl cyanoacetate is an organic compound that contains a carboxylate ester and a nitrile. It is a colourless liquid with a pleasant odor. This material is useful as a starting material for synthesis due to its variety of functional groups and chemical reactivity.
Pentabromopseudilin, the first reported marine microbial antibiotic, is a bioactive natural product that contains a highly halogenated 2-arrylpyrrole moiety. Pentabromopseudilin (PBP) is a unique hybrid bromophenol-bromopyrrole compound that is made up of over 70% bromine atoms, contributing to its potent bioactivity. PBP was first isolated from Pseudomonas bromoutilis, and has since been found to be produced by other marine microbes, including Alteromonas luteoviolaceus, Chromobacteria, and Pseudoalteromonas spp.
