N-H hydrogen-bond donors

Figure 1.12 Stereo-defined structure of first turn of an a-helix to demonstrate the atom separation between N—H hydrogen bond donors and C=0 hydrogen bond acceptors. The C=0 acceptor of each n-th residue forms a hydrogen bond link with the N—H bond donor of the (n -I- 4)-th residue defining an atom separation of 13 between acceptor 0-atom and donor H-atom. Peptide backbone bonds are colour coded in the same way as in Figs. 1.6 and 1.8.

We first showed that hydridic-protonic bonds between ion pairs of anionic hydrides and potassium(aza-crown) cations that have one N-H hydrogen bond donor can be readily observed in solution and the solid state [16,17]. The anionic... 

Fig. 8 Hydrogen-bonding networks in salts of perhalometallate complexes [MXn] (X=Cl, Br. etc. M=Pt. Zn. Mn. Pb. etc.) with organic cations possessing N—H hydrogen-bond donor functionality.

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