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We present a building-block approach toward functionalized CB[7] derivatives by the condensation of methylene-bridged glycoluril hexamer 1 and glycoluril bis(cyclic ethers) 2 and 12. The CB[7] derivatives Me₂CB[7] and CyCB[7] are highly soluble in water (264 mM and 181 mM, respectively). As a result of the high intrinsic solubility of Me₂CB[7], it is able to solubilize the insoluble benzimidazole drug albendazole. The reaction of hexamer 1 with glycoluril derivative 12, which bears a primary alkyl chloride group, gives CB[7] derivative 18 in 16% isolated yield. Compound 18 reacts with NaN₃ to yield azide-substituted CB[7] 19 in 81% yield, which subsequently undergoes click reaction with propargylammonium chloride (21) to yield CB[7] derivative 20 in 95% yield, which bears a covalently attached triazolyl ammonium group along its equator. The results of NMR spectroscopy (¹H, variable-temperature, and DOSY …