The aldol reaction is an important carbon-carbon bond formation reaction in
organic chemistry. In its usual form, it involves the nucleophilic addition
of a ketone enolate to an aldehyde to form an aldol (β-hydroxy ketone), a
structural unit found in many naturally occurring molecules and
pharmaceuticals. Sometimes, the aldol addition product loses a molecule of
water during the reaction to form an α,β-unsaturated ketone. This is called
an aldol condensation. The aldol reaction was discovered independently by
Charles-Adolphe Wurtz and by Alexander Porfyrevich Borodin in 1872. Borodin
observed the aldol dimerization of 3-hydroxybutanal from acetaldehyde under
acidic conditions. The aldol reaction is used widely in the large scale
production of commodity chemicals such as pentaerythritol. The aldol
structural motif is especially common in polyketides, a class of natural
products from which many pharmaceuticals are derived, including the potent
immunosuppressant FK506, the tetracycline antibiotics, and the antifungal
agent amphotericin B. Extensive research on the aldol reaction has produced
highly efficient methods which enable the otherwise challenging synthesis of
many polyketides in the laboratory.
Read the rest of this article:
<http://en.wikipedia.org/wiki/Aldol_reaction>
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Today's selected anniversaries:
1898:
The United States Navy battleship USS Maine exploded and sank in Havana,
Cuba, killing more than 260 people and precipitating the Spanish-American
War.
<http://en.wikipedia.org/wiki/USS_Maine_%28ACR-1%29>
1942:
World War II: Japanese forces led by General Tomoyuki Yamashita captured
Singapore, the largest surrender of British-led military personnel in
British history.
<http://en.wikipedia.org/wiki/Battle_of_Singapore>
1971:
The British pound sterling and the Irish pound were decimalised on what is
called Decimal Day.
<http://en.wikipedia.org/wiki/Decimal_Day>
1989:
The Soviet Union officially announced that all of its troops had withdrawn
from Afghanistan after a nine-year conflict.
<http://en.wikipedia.org/wiki/Soviet_war_in_Afghanistan>
2003:
In one of the largest anti-war rallies in history, millions around the world
in approximately 800 cities took part in protests against the impending
invasion of Iraq.
<http://en.wikipedia.org/wiki/February_15%2C_2003_anti-war_protest>
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Wiktionary's word of the day:
exuviate (v):
To shed or cast off a covering, especially a skin; to slough; to moult
<http://en.wiktionary.org/wiki/exuviate>
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Wikiquote quote of the day:
Kings had always been involving and impoverishing their people in wars,
pretending generally, if not always, that the good of the people was the
object. This our convention understood to be the most oppressive of all
kingly oppressions, and they resolved to so frame the Constitution that no
one man should hold the power of bringing this oppression upon us.
--Abraham Lincoln
<http://en.wikiquote.org/wiki/Abraham_Lincoln>