3TC & BCH-13520 4-amino-1-[(2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl]-2(1H)-pyrimidinone & {(2R,4R)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-1,3-dioxolan-2-yl}methanol AIDS-107983 AIDS107983