Crystal structure of HIV-1 RT in complex with 4a (PDB ID: 5TUQ). Analogue 4a (cyan sticks) binds at the NNRTI binding pocket of RT (Fingers, blue; Palm, red; Thumb, green; Connection, yellow; RNase H, orange; p51, gray). Inset: cross-eyed stereo view of 4a at the NNRTI binding pocket with a 2.7 Å 2Fo-Fc electron density map at σ=1.0 in light blue.