1. The early 1920s saw the outbreak of a previously unrecognized disease of cattle in the northern United States and Canada. Cattle would die of uncontrollable bleeding from very minor injuries, or sometimes drop dead of internal hemorrhage with no external signs of injury. In 1921, Frank Schofield, a Canadian veterinarian, determined that the cattle were ingesting moldy silage made from sweet clover that functioned as a potent anticoagulant.In 1929, North Dakota veterinarian Dr L.M. Roderick demonstrated that the condition was due to a lack of functioning prothrombin.
2. After an incident in 1951, where a US Army inductee unsuccessfully attempted suicide with warfarin and recovered fully,studies began in the use of warfarin as a therapeutic anticoagulant
3. A 2003 theory posits that warfarin was used by a conspiracy of Lavrenty Beria, Nikita Khrushchev and others to poison Soviet leader Joseph Stalin.
 

The CAS registry number of Warfarin is 81-81-2. The IUPAC name is 4-hydroxy-3-(3-oxo-1-phenylbutyl)-2H-chromen-2-one. Its EINECS registry number is 201-377-6. In addition, the molecular formula is C₁₉H₁₆O₄ and the molecular weight is 308.33. It is a kind of white to off-white crystalline powder and belongs to the classes of Coumarins; Insecticide; Intermediates & Fine Chemicals; Pharmaceuticals; Miscellaneous Compounds. And it is a synthetic derivative of dicoumarol, a 4-hydroxycoumarin-derived mycotoxin anticoagulant originally discovered in spoiled sweet clover-based animal feeds.

Physical properties about this chemical are: (1)ACD/LogP: 3.13 ; (2)ACD/LogD (pH 5.5): 2; (3)ACD/LogD (pH 7.4): 1; (4)ACD/BCF (pH 5.5): 21; (5)ACD/BCF (pH 7.4): 1; (6)ACD/KOC (pH 5.5): 157; (7)ACD/KOC (pH 7.4): 3; (8)#H bond acceptors: 4; (9)#H bond donors: 1; (10)#Freely Rotating Bonds: 5; (11)Polar Surface Area: 63.6 Å²; (12)Index of Refraction: 1.635; (13)Molar Refractivity: 84.447 cm³; (14)Molar Volume: 235.758 cm³; (15)Polarizability: 33.477 ×10^-24cm³; (16)Surface Tension: 58.658 dyne/cm; (17)Density: 1.308 g/cm³; (18)Flash Point: 188.828 °C; (19)Enthalpy of Vaporization: 82.854 kJ/mol; (20)Boiling Point: 515.155 °C at 760 mmHg.

Preparation of Warfarin: it can be prepared by 4-hydroxy-chromen-2-one and 4-phenyl-but-3-en-2-one. This reaction will need catalyst triethylbenzylammonium chloride and solvent H₂O. The reaction time is 2 hours by heating. The yield is about 82%.

Uses of Warfarin: is used to decrease the tendency for thrombosis or as secondary prophylaxis (prevention of further episodes) in those individuals that have already formed a blood clot (thrombus). And is also used in antiphospholipid syndrome. It has been used occasionally after heart attacks (myocardial infarctions), but is far less effective at preventing new thromboses in coronary arteries. In addition, it can be used to get 3-fluoro-3-(3-oxo-1-phenyl-butyl)-chroman-2,4-dione. This reaction will need reagent (CF₃SO₂)₂NF and solvent CHCl₃ and H₂O. The reaction time is 15 minutes at reaction temperature of 35 °C. The yield is about 92%.

When you are using this chemical, please be cautious about it as the following:
It is toxic if swallowed and may cause harm to the unborn child. And it has danger of serious damage to health by prolonged exposure. In addition, it is harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment. It is refer to special instructions/safety data sheets. Avoid exposure - obtain special instructions before use. During using it, not recommended for interior use on large surface areas. In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.). You should avoid release to the environment.

You can still convert the following datas into molecular structure:
(1)SMILES: CC(=O)CC(C\1=C(/O)c2ccccc2OC/1=O)c3ccccc3
(2)InChI: InChI=1/C19H16O4/c1-12(20)11-15(13-7-3-2-4-8-13)17-18(21)14-9-5-6-10-16(14)23-19(17)22/h2-10,15,21H,11H2,1H3
(3)InChIKey: PJVWKTKQMONHTI-UHFFFAOYAW

The toxicity data is as follows: