Structure of Thiosemicarbazide (CAS NO.79-19-6):

IUPAC Name: aminothiourea 
Empirical Formula: CH₅N₃S
Molecular Weight: 91.1355 
EINECS: 201-184-7
Index of Refraction: 1.666
Molar Refractivity: 24.63 cm³
Molar Volume: 66.2 cm³
Polarizability: 9.76× 10^-24cm³
Surface Tension: 91 dyne/cm
Density: 1.376 g/cm³
Flash Point: 80 °C
Enthalpy of Vaporization: 44.49 kJ/mol 
Melting Point: 180-183 °C (dec.)(lit.)
Boiling Point: 208.6 °C at 760 mmHg
Vapour Pressure: 0.212 mmHg at 25°C 
Water Solubility: soluble 
Stability: Stable. Incompatible with strong oxidizing agents. 
Physical Appearance: Product Categories: Pharmaceutical Intermediates;organic sulfide 
 

EPA Extremely Hazardous Substances List. Reported in EPA TSCA Inventory.

Hazard Codes:T+
Risk Statements:28-52/53-26/27/28 
R28:Very toxic if swallowed. 
R52/53:Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment. 
R26/27/28:Very toxic by inhalation, in contact with skin and if swallowed.
Safety Statements:22-26-36/37-45-61-28A-36/37/39 
S22:Do not breathe dust. 
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S36/37:Wear suitable protective clothing and gloves. 
S45:In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) 
S61:Avoid release to the environment. Refer to special instructions / safety data sheets. 
S28:After contact with skin, wash immediately with plenty of soap-suds. 
S36/37/39:Wear suitable protective clothing, gloves and eye/face protection.
RIDADR:UN 2811 6.1/PG 2
WGK Germany:3
RTECS:VT4200000
F:8-9-23
HazardClass:6.1
PackingGroup:II
HS Code:29309070
Poison by ingestion, intraperitoneal, and intravenous routes. Questionable carcinogen with experimental tumorigenic data. Human mutation data reported. When heated to decomposition it emits very toxic fumes of NO_x and SO_x.

Thiosemicarbazide has the Synonyms of 1-Amino-2-thiourea; 1-Aminothiourea; 2-Thiosemicarbazide; 3-Thiosemicarbazide; Hydrazinecarbothioamide; N-Aminothiourea; NSC 2213; Semicarbazide, 3-thio-; Semicarbazide, thio-; Thiocarbamoylhydrazine; Thiocarbamylhydrazine. With the CAS NO.79-19-6, it is a white crystalline solid. Thiosemicarbazide is used for the synthesis of anti-TB drugs such as Thioacetazone and sulfa drugs. And it is used as a pesticide intermediate, rubber additives, synthetic resin additives and analytical reagent. It is used for the preparation of carbamate insecticides and thiadiazole fungicides and also used as a rodenticide intermediate.

Physical properties about Thiosemicarbazide are: (1)ACD/LogP: -1.155; (2)# of Rule of 5 Violations: 1; (3)ACD/LogD (pH 5.5): -1.16; (4)ACD/LogD (pH 7.4): -1.16; (5)ACD/BCF (pH 5.5): 1.00; (6)ACD/BCF (pH 7.4): 1.00; (7)ACD/KOC (pH 5.5): 5.61; (8)ACD/KOC (pH 7.4): 5.60; (9)#H bond acceptors: 3; (10)#H bond donors: 5; (11)#Freely Rotating Bonds: 1; (12)Index of Refraction: 1.667; (13)Molar Refractivity: 24.637 cm³; (14)Molar Volume: 66.201 cm³; (15)Polarizability: 9.767 10-24cm³; (16)Surface Tension: 91.0770034790039 dyne/cm; (17)Density: 1.377 g/cm³; (18)Flash Point: 79.953 °C; (19)Enthalpy of Vaporization: 44.485 kJ/mol; (20)Boiling Point: 208.59 °C at 760 mmHg; (21)Vapour Pressure: 0.211999997496605 mmHg at 25°C

When you are using this chemical, please be cautious about it as the following:
1. Do not breathe dust;
2. In case of contact with eyes, rinse immediately with plenty of water and seek medical advice;
3. Wear suitable protective clothing and gloves;
4. In case of accident or if you feel unwell, seek medical advice immediately (show label where possible);
5. Avoid release to the environment. Refer to special instructions safety data sheet;
6. Wear suitable protective clothing, gloves and eye/face protection;

You can still convert the following datas into molecular structure:
(1)InChI=1S/CH5N3S/c2-1(5)4-3/h3H2,(H3,2,4,5);
(2)InChIKey=BRWIZMBXBAOCCF-UHFFFAOYSA-N;
(3)SmilesC(NN)(N)=S;

The toxicity data is as follows: