A variety of 6, 7-substituted-5, 8-quinolinequinones were synthesised and assessed for their anti-tumour and anti-inflammatory activities, and their ability to inhibit the growth of Mycobacterium bovis BCG. In particular, the introduction of a sulfur group at the 7-position of the quinolinequinone led to the discovery of two compounds, 6-methylamino-7- methylsulfanyl-5, 8-quinolinequinone (10a) and 6-amino-7-methylsulfonyl-5, 8- ...