Monothiourea 1 was obtained as the unique product following the three-step sequence described above (Scheme 2, steps 1-3). Phenyl isocyanate (0.9 equiv.) or 1,4-phenylene diisocyanate (0.45 equiv.) was then added and reacted in situ with the remaining free amino group of 1 (Scheme 2, Step 4). In both cases, no by-products were observed by 1 H NMR, indicating the exclusive formation of thiourea-urea 2 or dithiourea-diurea 3. As host Ox3 was regenerated, the cyclic four-step sequence could be repeated under similar conditions (see the Experimental Part). No differences were observed between the second and first cycles, products 1 and then 2 or 3 being quantitatively obtained without any trace of by-products. This remarkable result validates the strategy that consists in accumulating selectively functionalized products through the one-pot recycling of the molecular container.