However, protons 1 and 2 on the dipyrromethene subunits were shifted downfield, reflecting the attenuated shielding effect from the orthogonal macrocycle. Notably, protons 11 attached to the nitrogen atoms, which should be highly shielded by the overlapping aromatic macrocycles, appeared at a lower field (δ = 3.96 ppm) compared to those in OCT-2 (δ = 1.89 ppm). This anomalous shift is attributed to hydrogen bonding between the interlocked dipyrromethene subunits (Supplementary Fig. ).