Nitrile is an
organic compounds containing cyano group (-C》N, containing trivalent nitrogen)
which is attached to one carbon atom with the general formula RC》N. Their names
are corresponding to carboxylic acids by changing '-ic acid' to the suffix,
'-onitrile' which denotes only the 》N atom (triply bound) excluding the carbon
atom attached to it, or the suffix, '-carbonitrile' where the carbon atom in
the -CN is included, whichever preserves a single letter O. Examples are
acetonitrile from acetic acid and benzonitrile from benzoic acid. The prefix,
'cyano-' is used as an alternative naming system to indicate the presence of a
nitrile group in a molecule for the compounds of salts and organic derivatives
of hydrogen cyanide (HC》N). Isocyanides are salts and hydrocarbyl derivatives
from the isomer, HN+》C-. Sodium cyanide,
NaCN; potassium cyanide, KCN; calcium cyanide, Ca(CN)2; and hydrocyanic (or
prussic) acid, HCN are examples. Chemically, the simple inorganic cyanides
resemble chlorides in many ways. Organic nitriles act as solvents and are
reacted further for various application including;
·
Extraction solvent for fatty acids, oils and unsaturated hydrocarbons ·
Solvent for spinning and casting and extractive distillation based on its
selective miscibility with organic compounds. · Removing agent of
colouring matters and aromatic alcohols · Non-aqueous solvent for
titrations and for inorganic salts · Recrystallization of steroids ·
Parent compound for organic synthesis · Solvent or chemical intermediate in
biochemistry (protein sequencing and DNA synthesis) · High-pressure
liquid chromatographic analysis · Catalyst and component of
transition-metal complex catalysts · Stabilizer for chlorinated
solvents · Chemical intermediate and solvent for perfumes and
pharmaceuticals Mandelonitrile is the
cyanohydrin from benzaldehyde. Naturally occurring mandelonitrile is found in the millipede Apheloria corrugata
as a defense mechanism. when Apheloria is about to be attacked, mandelonitrile decomposes enzymatically into
benzaldehyde and a poison (hydrogen cyanide). Aamygdalin is known as laetrile
which has been used as an anti-cancer drug. But it is
known that it does not kill cancerous cells selectively.
Mandelic Acid, phenylglycollic acid, is an alpha-hydroxy acid (AHA) which has a
hydroxyl group on the carbon atom next to the acid group. If the hydroxy group
is on the second carbon next to the acid group, it is called beta-hydroxy acid.
Glycolic acid is the simplest AHA which has
dual functionality of alcohol and acid in a low mole weight structure. Because of its small molecular weight
and size, it has a better capability to penetrate skin. AHA is used extensively
in cosmetics. It is known that it diminishes the lines on the skin and make
skins look young by acting as a humectant to absorb moisture in air and by
exfoliating action to break the bonds between dead skin cells. Mandelic Acid (
alpha-hydroxybenzeneacetic acid) is the smallest AHA among compounds which have
aromatic group. It has an asymmetric carbon atom and thus has two chiral
isomers; the dextro-, levo-. The D- and L-mandelic acid are enantiomers (also
called enantiomorph; each molecule is asymmetrical and has the mirror image of
the other) affect pharmaceutical activity. It is a white crystalline compound;
melting at 118 C; partially soluble in water; freely soluble in isopropyl and
ethyl alcohol; darkening upon exposure to light. Its structure provide the
bacteriostatic property. It is excreted well in the urine. It is used as a
antiseptic ingredient particularly against urinary tract infections. Mandelic
acid and its derivatives are used to apply the dual activities as an antibacterial
agent and as an antiaging agent (AHA activity) similar to glycolic acid. It is
used as an intermediate for the synthesis of target molecules for other applications. Naturally occurring mandelic acid is found when amygdalin (a cyanogenetic
glycoside found in many plants including bitter almond, apricot, and wild cherry) is spirit by hydrolysis with hydrochloric
acid, while amygdalin is broken down into glucose, benzaldehyde, and prussic
acid (hydrogen cyanide) in the presence of sulfuric acid.
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