Abstract A series of novel S-DABO analogues of 5-alkyl-2-arylthio-6-((3, 4-dihydroquinolin-1 (2H)-yl) methyl) pyrimidin-4 (3H)-ones were synthesized and evaluated as inhibitors of human immunodeficiency virus type-1 (HIV-1). Among them, the most potent HIV-1 inhibitors were compounds 6c1, 6c6, and 6b1 (EC 50= 0.24±0.05, 0.38±0.13, 0.39±0.05 μM, respectively), which possess improved or similar HIV-1 inhibitory activity compared with ...