Here is a nice paper that extensively reviews the different potential treatments that are being considered for COVID-19.
Here is a NYTimes article by Carl Zimmer that links to the above article and describes the efforts to discover a COVID-19 therapy.
“Hundreds of Scientists Scramble to Find a Coronavirus Treatment“
Chemical structure of hydroxychloroquine (approved for treatment of malaria infection and autoimmune diseases such as rheumatoid arthritis and lupus)