Is quinine another name for that malaria drug that shows promise to treat it?
Yes.
The British living abroad, over the years, survived many an epidemic, esp. malaria, by drinking large quantities of gin and tonic.
Tonic is watered down quinine.
Not exactly. Chloroquine and Hydrochloroquine are similar to Quinine and both are used to treat malaria. I’m not sure quinine has actually been used against CV19, but chloroquine and hydrocloroquine have. Some people might interchange the names. I know in the navy, when the docs told us they were giving us quinine, they actually gave us chloroquine.
I think its an ingredient (or co-molecule, if you will). Not sure where I saw more details, but basically, yes.