**4. Methods**

## *4.1. NMR Data*

The ROEs for compounds **1**–**3** were taken from refs [60,69]. For compounds **1** and **2** three ROESY spectra with different mixing times (100, 150 and 200 ms) were measured [60,69]. In the case of **3**, only one ROESY spectrum with a mixing time of 300 ms was recorded [69]. The spectra were integrated with TOPSPIN and SPARKY.

For the compounds **4** and **5**, sets of NOEs were predicted using the corresponding X-ray structures and all proton-proton contacts ≤ 3.5 Å. All NOEs involving CH3– or CH2– groups were treated as averaged values between unassigned (diastereotopic) protons only, in order to reduce the amount of prior information, thus simulating situations where no diastereotopic assignment was possible. The *ortho*- and *ortho*'-protons of the central benzene ring (C-17 to C-22) were treated equivalently (see Tables S4 and S5). Simulated RDC data for **4** and **5** was taken from Ref. [22] for three independent alignment scenarios, respectively.
