Alpha-, structural notation

What appears to be the first SDG paper was concerned with visualizing the hits of a database search. The structures were entered in Wiswesser line notation (WLN) and manipulated in a closely descended connection table. Drawing sequence was essentially the same as the WLN order. To avert atom overlap, stretching was used in branched chains (same approach as shown later in Figure 62), and drawing directions from ring alpha substituents were redirected as necessary. 

The alpha-helix corresponds to the structure shown in Figure 14.1, with two possible directions of notation corresponding to right-handed and left-handed helixes. 

---