In chemistry, a hydrochloride is an

acid salt An acid is a molecule or ion capable of either donating a proton (i.e. hydrogen cation, H+), known as a Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid. The first category of acids are the ...

resulting, or regarded as resulting, from the reaction of

hydrochloric acid Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is ...

with an organic base (e.g. an

amine In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of elec ...

). An alternative name is chlorhydrate, which comes from French. An archaic alternative name is muriate, derived from hydrochloric acid's ancient name: muriatic acid.

Uses

Converting

s into their hydrochlorides is a common way to improve their

water solubility An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, also known as sodium chloride (NaCl), in water w ...

, which can be desirable for substances used in medications. The

European Pharmacopoeia The ''European Pharmacopoeia'' (''Pharmacopoeia Europaea'', ''Ph. Eur.'') is a major regional pharmacopoeia which provides common quality standards throughout the pharmaceutical industry in Europe to control the quality of Pharmaceutical drug, ...

lists more than 200 hydrochlorides as active ingredients in medications. These hydrochlorides, compared to

free base In chemistry, a free base (freebase, free-base) is a term for the neutral form of an amine or other Lewis base. The term is used in the pharmaceutical industry in contrast to salt-based formulations like hydrochlorides. The amine is often an ...

s, may more readily dissolve in the gastrointestinal tract and be absorbed into the bloodstream more quickly. Additionally, many hydrochlorides of amines have a longer shelf-life than their respective free bases. Amine hydrochlorides represent latent forms of a more reactive free base. In this regard, formation of an amine hydrochloride confers

protection Protection is any measure taken to guard something against damage caused by outside forces. Protection can be provided to physical objects, including organisms, to systems, and to intangible things like civil and political rights. Although ...

. This effect is illustrated by the hydrochlorides of the amino acids.

Glycine methyl ester hydrochloride Glycine methyl ester hydrochloride is the organic compound with the formula H3O2CCH2NH3l. A white, water-soluble solid, it is the hydrochloride of the methyl ester of the amino acid glycine. Synthesis and reactions Glycine methyl ester hydrochlo ...

is a shelf-stable salt that can be readily converted to a reactive glycine methyl ester, a compound that is not shelf-stable.

References

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Uses

See also

References