State-owned China National Chemical Corp., or ChemChina, is negotiating to buy agribusiness giant Syngenta for about US$43 billion in what would be the largest foreign acquisition by a mainland company, The Wall Street Journal reported, citing unnamed sources. Completing the purchase of the Swiss firm would entail a gauntlet of regulatory scrutiny in both Europe and the US for ChemChina, with North America currently accounting for nearly a quarter of Syngenta’s sales; it is the top seller of pesticide in terms of revenue in the US, in addition to selling an estimated 10% of soybean seeds and 6% of corn there.