**05-01-18UN** | Title | **Determining Configuration Step 2** | Caption | The second step in determining the configuration of a chiral stereocenter is to orient the lowest-priority group behind the stereocenter and determine whether the remaining groups are priority-ordered in a clockwise or counterclockwise fashion around the stereocenter. | Notes | If groups are ordered around a chiral stereocenter such that the lowest-priority group is behind the stereocenter and the remaining groups are in front of the stereocenter and ordered clockwise around the stereocenter in ascending priority-numbered order (i.e., 1 to 3 for carbon), the chiral stereocenter is assigned an "R" designation. The "R" in R configuration is from rectus, which is latin for "right." Counterclockwise ordering yields an "S" (sinister, or left) designation. | Keywords | R, configration, determining, configuration, step, 2, priority, clockwise, counterclockwise, rectus, sinister, S | |