Biguanid Chemische Eigenschaften,Einsatz,Produktion Methoden
Beschreibung
French physician Jean Sterne published the first clinical trial in
1957 suggesting metformin as a treatment for diabetes. The
United Kingdom introduced this drug in 1958 followed by
Canada in 1972, and the United States in 1995. As of 2010,
metformin was one of only two oral antidiabetics in the World
Health Organization model list of essential medicines, the
other being glibenclamide. Metformin is believed to enjoy the
popularity of being the most widely prescribed antidiabetic
drug in the world. It has been estimated that the United States
alone has filled nearly a million prescriptions in 2010 for its
generic formulations. Biguanides are not hypoglycemic
agents; rather they promote euglycemia (antihyperglycemic).
Biguanides are used both as monotherapy and in combination
with other oral hypoglycemic agents to control hyperglycemia.
Although very safe in most instances, the major toxicity from
acute or chronic use of biguanides has been reported to be
lactic acidosis. In fact, the high rate of severe lactic acidosis was
the only major cause of withdrawal of phenformin from the US
market in 1976.
Chemische Eigenschaften
Biguanide [56-03-1], C2H7N5, Mr 101.11, mp 130 ℃ (which decomposes violently at 142 ℃), is a moderately strong base (pKb 2.9). It is readily soluble in water and ethanol, and insoluble in ether, benzene, and chloroform. The free base decomposes gradually in aqueous solution. Biguanide forms stable salts with most acids.
Verwenden
Biguanides are used as an oral drug for the management of
mild to moderately severe noninsulin-dependent diabetes
mellitus, or NIDDM, (Type II) in obese or overweight patients
who are usually above 40 years of age. It is important that for
the administration of this drug the disease should have adult
onset. Polymeric biguanides were originally developed as
a presurgery antimicrobial scrub and in 1977, it was introduced
in the market for treating pools and spas as a disinfectant under
the trade name Baquacil. The US Environmental Protection
Agency approved this agent as the only nonhalogen sanitizer of
pools and spas. Biguanide itself is combined with algaecides
and hydrogen peroxide for periodic oxidation of pools and
spas. Biguanides are incompatible with chlorine, ozone,
detergents, and ionizers, but are compatible with water ion
balancing chemicals. Biguanide in the form of polyaminopropyl
biguanide serves as a disinfectant, and preservative
for skin disinfection, contact lens cleaning solutions, and
deodorant body sprays. Biguanides reduce the surface tension
of water, which gives it a smoother feeling. They are stable in
sunlight and temperature. At recommended concentrations
when used in pools and spas, biguanides do not irritate the skin
or eyes and do not corrode the pool equipment.
Environmental Fate
Globally, hundreds of millions of patients are prescribed this
drug annually. Metformin was discovered before the era of
target-based drug discovery, and its molecular mechanism of
action remains an important focus of diabetes research.
Advances in our understanding of metformin’s molecular
targets are likely to enable target-based identification of secondgeneration
drugs with similar properties, a development that
has been a difficult task until now. Besides its potent antidiabetic
properties, Metformin’s potential as a targeted anticancer
agent is being explored in a number of laboratories throughout
the world.
läuterung methode
Crystallise biguanide from EtOH. It gives a red Cu derivative, and it forms salts with many metals. The monohydrochloride has m 235o [38664-03-8] and the dihydrochloride forms plates with m 248o (213-214o, also reported) [25836-74-2]. [Beilstein 3 H 93, 3 I 44, 3 II 76, 3 III 171, 3 IV 162.]
Biguanid Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
