As per the World Health Organisation's information, there is no evidence of sesame oil being able to kill new coronavirus (COVID-19).
According to the WHO's myth buster, it has posted an infographic on twitter on 1 February 2020 which clarifies that some chemical disinfectants can kill the 2019-nCoV on surfaces. These include bleach/chlorine-based disinfectants, ether solvents, 75% ethanol, peracetic acid and chloroform. However, they have little or no impact on the virus if applied on the skin.
The International Pharmaceutical Federation also refuted the claim regarding sesame oil in its information and interim guidelines to the public on coronavirus.
The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19 including symptoms, prevention and available treatment, please refer to the World Health Organisation or your national healthcare authority.