IARC Cancer Review: Group 2B IMEMDT    IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Man . 7 ,1987,p. 56.(World Health Organization, Internation Agency for Research on Cancer,Lyon, France.: ) (Single copies can be ordered from WHO Publications Centre U.S.A., 49 Sheridan Avenue, Albany, NY 12210) ; Animal Sufficient Evidence IMEMDT    IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Man . 7 ,1974,p. 53.(World Health Organization, Internation Agency for Research on Cancer,Lyon, France.: ) (Single copies can be ordered from WHO Publications Centre U.S.A., 49 Sheridan Avenue, Albany, NY 12210) . Reported in EPA TSCA Inventory.

The Methylthiouracil, also known as 4-Hydroxy-2-mercapto-6-methylpyrimidine, is an organic compound with the formula C₅H₆N₂OS. It belongs to the product category of Pyrimidine. Its EINECS registry number is 200-252-3. With the CAS registry number 56-04-2, its IUPAC name is 6-methyl-2-sulfanylidene-1H-pyrimidin-4-one. What's more, this chemical is a white powder. It is mainly used as surgical preparation of mild hyperthyroidism, thyroid storm, hyperthyroidism and postoperative treatment.

Physical properties of Methylthiouracil: (1)ACD/LogP: 0.31; (2)ACD/LogD (pH 5.5): 0.31; (3)ACD/LogD (pH 7.4): 0.24; (4)ACD/BCF (pH 5.5): 1.01; (5)ACD/BCF (pH 7.4): 1; (6)ACD/KOC (pH 5.5): 35.06; (7)ACD/KOC (pH 7.4): 29.79; (8)#H bond acceptors: 3; (9)#H bond donors: 2; (10)Index of Refraction: 1.638; (11)Molar Refractivity: 37.36 cm³; (12)Molar Volume: 103.9 cm³; (13)Surface Tension: 63 dyne/cm; (14)Density: 1.36 g/cm³; (15)Flash Point: 160.8 °C; (16)Enthalpy of Vaporization: 60.93 kJ/mol; (17)Boiling Point: 342.3 °C at 760 mmHg; (18)Vapour Pressure: 3.83E-05 mmHg at 25°C.

Preparation: this chemical can be prepared by acetoacetic acid ethyl ester and thiourea. This reaction will need 4 min with microwave irradiation. The yield is about 69%.

Uses of Methylthiouracil: The drug acts to decrease the formation of stored thyroid hormone, as thyroglobulin in the thyroid gland. The clinical effects of the drug to treat the hyperthyroid state can have a lag period of up to two weeks, depending on the stores of thyroglobulin and other factors.

When you are using this chemical, please be cautious about it as the following:
This chemical may cause damage to health. It may cause inflammation to the skin or other mucous membranes. In addition, it is harmful if swallowed. Whenever you will contact it, please wear suitable protective clothing and gloves. In case of accident or if you feel unwell seek medical advice immediately (show the label where possible).

You can still convert the following datas into molecular structure:
(1)Canonical SMILES: CC1=CC(=O)NC(=S)N1
(2)InChI: InChI=1S/C5H6N2OS/c1-3-2-4(8)7-5(9)6-3/h2H,1H3,(H2,6,7,8,9)
(3)InChIKey: HWGBHCRJGXAGEU-UHFFFAOYSA-N

The toxicity data is as follows:

Organism	Test Type	Route	Reported Dose (Normalized Dose)	Effect	Source
mouse	LD50	intraperitoneal	200mg/kg (200mg/kg)		National Technical Information Service. Vol. AD277-689,
mouse	LD50	oral	2125mg/kg (2125mg/kg)		Pharmaceutical Chemistry Journal Vol. 30, Pg. 320, 1996.
rabbit	LDLo	oral	2500mg/kg (2500mg/kg)		"Merck Index; an Encyclopedia of Chemicals, Drugs, and Biologicals", 11th ed., Rahway, NJ 07065, Merck & Co., Inc. 1989Vol. 11, Pg. 963, 1989.
rat	LD50	intraperitoneal	920mg/kg (920mg/kg)	LUNGS, THORAX, OR RESPIRATION: OTHER CHANGES	Farmaco, Edizione Scientifica. Vol. 13, Pg. 882, 1958.
rat	LD50	oral	1500mg/kg (1500mg/kg)		Nature. Vol. 157, Pg. 659, 1946.