N-Allylthiourea

Chemical properties

white crystals or powder. Melting point 76～78.5 ℃, relative density is 1.110, soluble in water and ethanol, slightly soluble in ethanol, insoluble in benzene, with a garlic odor. It is used as an additive for cyanide-free copper plating to increase the brightness and corrosion resistance of plated products.

The Uses of N-Allylthiourea

N-Allylthiourea is a nitrification inhibitor used in the study on the transformation of diclofenac, naproxen and bisoprolol under aerobic and anaerobic conditions. It is also used in medicine to minimize scar tissue in order to fight against a type of dermatitis. Further, it inhibits the growth of transplanted tumors in mice. It acts as a chelating agent. In addition, it is used in cosmetics, preservative and in organic synthesis.

Definition

ChEBI: Allylthiourea is a thiourea with a prop-2-enyl group attached to one of the amines. It has a role as a metabolite. It is functionally related to a thiourea.

Preparation

In the presence of potassium iodide, in ethanol solution, chloropropene is reacted with sodium thiocyanide to form allyl isothiocyanate, which is then ammoniated in ammonium hydroxide solution, concentrated, cooled and crystallized, filtered, washed, and recrystallized in ethanol or water to produce Allylthiourea.

General Description

White crystalline solid with a slight garlic odor.

Air & Water Reactions

Soluble in water.

Reactivity Profile

Allylthiourea may react vigorously with strong oxidizing agents. Can react exothermically with reducing agents (such as alkali metals and hydrides) to release gaseous hydrogen. May react exothermically with both acids and bases. May generate flammable gases in combination with aldehydes, nitrides, and hydrides. Incompatible with peroxides and acid halides.

Health Hazard

SYMPTOMS: Contact eczema due to sensitization in humans has been reported.

Fire Hazard

Flash point data are not available for Allylthiourea, but Allylthiourea is probably combustible.

Biochem/physiol Actions

N-Allylthiourea inhibits the growth of transplanted tumours in mice.

Purification Methods

Recrystallise it from H2O. It is soluble in 30 parts of cold H2O, and it is soluble in EtOH but insoluble in *C6H6. It has also been recrystallised from acetone, EtOH or ethyl acetate, after decolorising with charcoal. The white crystals have a bitter taste with a slight garlic odour and are TOXIC. An unstable crystalline form is obtained by recrystallising from the melt. [McCrone et al. Anal Chem 21 421 1949, Beilstein 4 IV 1072.]