Some examples include:
The End of the Apartheid System in South Africa
To end the apartheid system there were sanctions in South Africa, this is a link to further reading into the end of the apartheid system of South Africa:
http://www.fsmitha.com/h2/ch34-sa.htm
This is a link to a paper by an American university, which looks at the effect that the sanctions had on the apartheid:
http://www.econ.yale.edu/growth_pdf/cdp796.pdf
Proposed sanctions against Israel to stop its actions against Palestinians in Gaza
The sanctions which are being suggested against Israel are in an attempt to prevent them from being capable of terrorising Palestinians as their economy would feel the effect of the sanction as trading ceased with them and the world. This is a link to a news article which calls for sanctions to be put up against Israel:
http://www.imemc.org/article/57823
Sanctions against Cuba by the US
In cuba, when castro was in power the US put up sanctions against them to combat communism. Before the sanction two-thirds of Cuba's trade was with the US, so when the sanction came into place in 1962, there were serious problems with Cuba's economy, leading to them having to look to new markets. This is a link to a bbc news article:
http://news.bbc.co.uk/1/hi/world/americas/67554.stm
The way that this effects international business is through the collapse of some trade routes, which may have been cut off by sanctions. This could mean that businesses who did trade with certain countries may no longer be able to and therefore lose a lot of business. Also domestic businesses may be more protected by the government using protectionism methods. This is very common in a recession like at the moment where businesses are in a lot of financial trouble.Governments also effect international business by encouraging bribes on domestic business deals