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Enamel paint
Enamel paint is a hard, glossy, wear-resistant organic coating with oil, alkyd, or synthetic resin binders, air-dried or baked ('Japan'); distinct from vitreous glass enamel; key alkyd chemistry dates to Kienle's 1927 patent and ICI's 1932 Dulux.
Enamel-dentin fracture
Enamel-dentin fracture (uncomplicated crown fracture, ICD-11 NA0D.02): traumatic tooth fracture confined to enamel and dentin without pulp exposure; treated by fragment reattachment or glass-ionomer/composite coverage per IADT 2020 guidelines.
Enamel-renal syndrome
Enamel-renal syndrome (ERS, OMIM 204690), also called amelogenesis imperfecta-nephrocalcinosis or MacGibbon syndrome, is an autosomal recessive FAM20A disorder combining hypoplastic enamel, failed tooth eruption, gingival fibromatosis, and nephrocalcinosis.
Enamelin
Enamelin (ENAM) is a secreted 186 kDa glycoprotein, one of three major enamel matrix proteins, essential for enamel crystal formation at the mineralization front; ENAM mutations cause autosomal dominant amelogenesis imperfecta.
Enamine
An enamine is an alkene bearing an amine on a double-bond carbon, formed from an aldehyde or ketone and a secondary amine, and key to asymmetric organocatalysis.
Enamine REAL
Enamine REAL (REadily AccessibLe) is a make-on-demand compound library from Enamine Ltd, founded in Kyiv in 1991, with compounds synthesized to order in a few weeks and over 80 percent success.
Enamorada
Enamorada (1946) is Emilio Fernández's Golden Age Mexican film, a Taming of the Shrew adaptation set in revolutionary Cholula, starring María Félix and Pedro Armendáriz, photographed by Gabriel Figueroa, an Ariel-winning classic restored in 4K in 2018.
Enamtila
Enamtila (é-nam-ti-la, 'House of Life'), temple of the god Bēl-mātāti (Enlil) in the Kumar district of Babylon, western inner city; one of seven temples per Tintir Tablet IV, attested in Old Babylonian and Kassite texts, now unlocated.
Enang Oil and Gas Field
Enang is an oil and gas field in the shallow offshore Niger Delta, Nigeria, discovered by Mobil in 1968, with production from 1974 across OML 67 and 70.
Enannatum I
Enannatum I, also written Enanatum I, was a ruler of the Sumerian city-state of Lagash around 2425–2420 BC, brother and successor of Eannatum and father of Entemena.
Enannatum II
Enannatum II was a ruler of the Sumerian city-state of Lagash around 2390 BC, son and successor of Entemena and the last king of its First Dynasty.
Enannatumma
Enannatumma, also written Enanatuma, was an en-priestess of the moon god Nanna at Ur, a daughter of King Išme-Dagan of Isin, who held the office for about 67 years until her death around 1886 BC.
Enantioconvergent catalysis
Enantioconvergent catalysis is a form of asymmetric catalysis in which a chiral catalyst converts both enantiomers of a racemic starting material into one enantioenriched product.
Enantioconvergent cross-coupling
Enantioconvergent cross-coupling is a reaction in which both enantiomers of a racemic alkyl electrophile yield one product enantiomer under a chiral catalyst, pioneered by Gregory Fu's 2005 nickel-catalyzed Negishi couplings.
Enantioconvergent metallaphotoredox cross-coupling
Enantioconvergent metallaphotoredox cross-coupling is an asymmetric bond-forming method where a photoredox catalyst generates carbon radicals and a chiral metal catalyst, usually nickel, captures them into one enantioenriched product.
Enantiomer
An enantiomer, also called an optical isomer, is one of a pair of molecules that are mirror images and cannot be superimposed, differing only in how they rotate light.
Enantiomeric excess
Enantiomeric excess, also known as optical purity, measures how much one enantiomer predominates in a mixture, ranging from 0% for a racemate to 100% for a pure one.
Enantiomeric separation
Enantiomeric separation is a class of analytical chemistry methods, mostly chromatographic or electrophoretic, that resolves a racemic mixture into its enantiomers so a chiral compound's composition can be measured.
Enantiopure drugs
Enantiopure drugs are pharmaceuticals consisting of a single enantiomer of a chiral molecule rather than a racemate, exemplified by escitalopram and esomeprazole and produced by chiral synthesis or resolution.
Enantioselective [2+2] photocycloaddition
The enantioselective [2+2] photocycloaddition is a light-driven reaction joining two alkenes into a cyclobutane ring, where a chiral catalyst or sensitizer selects which enantiomer predominates.
Enantioselective atom-transfer radical addition
Enantioselective atom-transfer radical addition is a class of radical reactions in which a radical adds to an alkene and a chiral catalyst sets the stereochemistry.
Enantioselective C–H activation
Enantioselective C–H activation is a class of catalytic reactions in which a transition metal cleaves a carbon–hydrogen bond of a prochiral substrate, producing one enantiomer preferentially.
Enantioselective C–H activation with MPAA ligands
Enantioselective C–H activation with MPAA ligands is a palladium-catalyzed strategy introduced by Jin-Quan Yu's group at Scripps Research in 2008, where chiral amino acid ligands deliver up to 99% ee.
Enantioselective C–H amidation
Enantioselective C–H amidation is a class of catalytic reactions converting carbon–hydrogen bonds directly into chiral amides, a field that emerged as a distinct area around 2019.
Enantioselective C–H amination
Enantioselective C–H amination is the catalytic conversion of a C–H bond into a C–N bond in a way that favors one enantiomer, giving optically enriched chiral amines from hydrocarbons without pre-installed leaving groups.
Enantioselective C–H borylation
Enantioselective C–H borylation is a class of catalytic reactions replacing a carbon–hydrogen bond with a carbon–boron bond while favoring one enantiomer of the chiral organoboronate product.
Enantioselective fluorination
Enantioselective fluorination, also called asymmetric fluorination, uses catalytic methods to add fluorine to achiral substrates so one enantiomer forms preferentially, supplying chiral building blocks for pharmaceuticals.
Enantioselective Minisci reaction
The enantioselective Minisci reaction is an asymmetric variant of the Minisci reaction, first made catalytic in 2018 at Cambridge, that adds carbon radicals to basic heteroarenes enantioselectively.
Enantioselective photoredox catalysis
Enantioselective photoredox catalysis is a family of organic synthesis methods in which a visible-light photoredox catalyst makes radical intermediates while a chiral catalyst sets the product's stereochemistry.
Enantioselective synthesis
Enantioselective synthesis, also called asymmetric synthesis, is chemical synthesis that produces one enantiomer of a chiral molecule in preference over its mirror image, measured by enantiomeric excess.