Figure 5

Three arrangements of the same atoms attached to a chiral carbon that differ in the angle between the two planar bonds that includes the stereobond. (a) The angle is > 180°: the hydrogen is considered to be below the plane and behind the wedge. (b) The angle is ~180°: some software will treat the stereochemistry as undefined depending on how close the angle is to 180°. (c) The angle is < 180°: the hydrogen is considered to be opposite the wedge. This is an enantiomer of (a).