Гуанидин гидрохлорид

Химические свойства

Guanidine hydrochloride, a strong organic base, appears as white crystal powder or yellowish lumps that are almost insoluble in acetone, benzene, and ether. In physiological pH, it exists primarily as guanidium ions. It is a natural byproduct of protein metabolism found in urine and is commonly used in protein denaturation in laboratory research.

Использование

Guanidine hydrochloride is used for purification of proteins and nucleic acids. It can be used as a medicine, organic synthesis intermediate and is used in dyes. It acts as an intermediate in the preparation of sulfadiazine, which is an important raw material for sulfamethyldiazine, sulfamethazine and folic acid. It is utilized in the synthesis of 2-amino-pyrimidine, 2- amino -6- methyl-pyrimidine and 2-amino -4,6 - dimethyl-pyrimidine. Also used in RNA isolation to dissociate nucleoproteins and inhibit RNase.

Определение

ChEBI: Guanidine Hydrochloride is an aminocarboxamidine, the parent compound of the guanidines. It is a strong organic base existing primarily as guanidium ions at physiological pH. It is found in the urine as a normal product of protein metabolism.

Подготовка

The process for preparing guanidine hydrochloride is as follows:
Step 1: Fritting - Combine dicyandiamide and ammonium chloride in a reactor with a 1:1.27 weight ratio and carry out a frit reaction at 170-230°C to obtain crude guanidine hydrochloride.
Step 2: Dissolving - Dissolve the crude guanidine hydrochloride in water at a 1:1 ratio at normal temperature. Then, add ammonium salt alkaloid in an amount determined by the ammonium salt content in the crude guanidine hydrochloride.
Step 3: Filtering - Remove raw materials and reaction by-products with filtration.
Step 4: Dehydrating - Dehydrate the filtered ground mother liquor at a high temperature.
Step 5: Crystallizing - Cool the supersaturated solution, concentrate, and crystallize to obtain high-purity guanidine hydrochloride.
Step 6: Repeat steps 2-5 and add dicyandiamide in the reactor with the guanidine hydrochloride to carry out frit reaction at 170-230°C for 3-4 hours to obtain even higher purity guanidine hydrochloride. This step can be repeated several times if needed.
Step 7: To obtain higher purity guanidine hydrochloride, subject the guanidine hydrochloride obtained in step 5 to steps 2-5 again, with the water ratio in step 2 adjusted to 1.5:1. This step can be repeated numerous times as required.

Общее описание

Guanidine hydrochloride (GdnHCl) is a well-known protein and enzyme denaturant. It is a small molecule and hydroscopic in nature. It is used to synthesis medicine, pesticide, dye and other organic compound, is the important material to make sulfanilamide medicine and folacin, and can be used as anti-static agent of compound fibre.

Опасность

Toxic by ingestion, evolves hydrogen chloride fumes on heating.

Методы очистки

Crystallise the hydrochloride from hot methanol by chilling to about -10o, with vigorous stirring. The fine crystals are filtered through fritted glass, washed with cold (-10o) methanol, dried at 50o under vacuum for 5hours. (The product is purer than that obtained by crystallisation at room temperature from methanol by adding large amounts of diethyl ether.) [Kolthoff et al. J Am Chem Soc 79 5102 1957, Beilstein 3 H 86, 3 II 71, 3 III 160, 3 IV 150.]