All articles starting with E
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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.
Enantioselective triplet energy transfer photocatalysis
Enantioselective triplet energy transfer photocatalysis is a strategy in organic synthesis in which a chiral photosensitizer transfers triplet energy from absorbed visible light to a bound substrate, yielding one enantiomer selectively.
Enantioselective triplet-sensitized [2+2] cycloadditions
Enantioselective triplet-sensitized [2+2] cycloadditions are photochemical reactions in which a photosensitizer transfers triplet energy to an alkene, with a chiral sensitizer or chiral catalyst imposing enantioselectivity.
Enantioselectivity
Enantioselectivity is the preferential formation of one enantiomer over another in a chemical reaction, measured by enantiomeric excess; high enantioselective catalysis typically means over 90% ee.
Enantiospecific sp3–sp3 cross-coupling of boronic esters
Enantiospecific sp3–sp3 cross-coupling of boronic esters is a family of reactions joining enantioenriched alkyl boronic esters to another sp3 carbon partner while transferring the stereocenter's configuration into the product.
Enantiotopic
Enantiotopic describes constitutionally identical atoms, groups, or faces in a molecule related only by mirror-type symmetry, where replacing one member gives one enantiomer and replacing the other gives its mirror image.
Enarodustat
Enarodustat (JTZ-951, brand Enaroy) is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor by Japan Tobacco for CKD anemia; approved in Japan (September 2020), South Korea, and China.
Enasidenib
Enasidenib (Idhifa, AG-221) is an oral first-in-class mutant IDH2 inhibitor approved in the US in 2017 for relapsed/refractory IDH2-mutant AML; it lowers 2-HG, induces differentiation, and carries a differentiation syndrome boxed warning.
Enauta
Enauta was a Brazilian oil and gas producer that operated the Atlanta heavy-oil field in the Santos Basin and merged into 3R Petroleum in 2024, forming Brava Energia.
Enayet Chowdhury
Md. Enayet Chowdhury is a Bangladeshi hydrology researcher and educator at BUET's Institute of Water and Flood Management who runs a popular Bangla explainer YouTube channel.
Enbaqom
Enbaqom (እንባቆም), born in Yemen around 1470, was a convert to Christianity who became abbot of Debre Libanos, counseled Emperor Galawdewos, and wrote the treatise Anqasa amin.