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Guest-Mediated Reversal of the Tumbling Process in Phosphorus-Dendritic Compounds Containing β-Cyclodextrin Units: An NMR Study.

ABSTRACT: The conformational study of dendritic platforms containing multiple β-cyclodextrin (βCD) units in the periphery is relevant to determine the availability of βCD cavities for the formation of inclusion complexes in aqueous biological systems. In this work, we performed a detailed conformational analysis in D₂O, via 1D and 2D NMR spectroscopy of a novel class of phosphorus dendritic compounds of the type P₃N₃-[O-C₆H₄-O-(CH₂)_n-βCD]₆ (where n = 3 or 4). We unambiguously demonstrated that a functionalized glucopyranose unit of at least one βCD unit undergoes a 360° tumbling process, resulting in a deep inclusion of the spacer that binds the cyclodextrin to the phosphorus core inside the cavity, consequently limiting the availability of the inner cavities. In addition, we confirmed through NMR titrations that this tumbling phenomenon can be reversed for all βCD host units using a high-affinity guest, namely 1-adamantanecarboxylic acid (AdCOOH). Our findings have demonstrated that it is possible to create a wide variety of multi-functional dendritic platforms.

SUBMITTER: Sorroza-Martinez K

PROVIDER: S-EPMC8230630 | biostudies-literature |

REPOSITORIES: biostudies-literature

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First Class of Phosphorus Dendritic Compounds Containing β-Cyclodextrin Units in the Periphery Prepared by CuAAC.

Project description:A new class of phosphorus dendritic compounds (PDCs) having a cyclotriphosphazene (P3N3) core and decorated with six β-cyclodextrin (βCD) units, named P3N3-[O-C6H4-O-(CH2)n-βCD]6, where n = 3 or 4 was designed, and the synthesis was performed using copper (I) catalyzed alkyne-azide cycloaddition (CuAAC). To obtain the complete substitution of the P3N3, two linkers consisting of an aromatic ring and an aliphatic chain of two different lengths were assessed. We found that, with both linkers, the total modification of the periphery was achieved. The two new obtained dendritic compounds presented a considerably high water solubility (>1 g/mL). The compounds comprised in this new class of PDCs are potential drug carrier candidates, since the conjugation of the βCD units to the P3N3 core through the primary face will not only serve as surface cover but, also, provide them the faculty to encapsulate various drugs inside the βCDs cavities.

| S-EPMC7570757 | biostudies-literature

Experimental characterization of the association of β-cyclodextrin and eight novel cyclodextrin derivatives with two guest compounds.

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| S-EPMC10896224 | biostudies-literature

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| S-EPMC4137772 | biostudies-literature

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| S-EPMC6953482 | biostudies-literature

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| S-EPMC7839762 | biostudies-literature

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| S-EPMC9868465 | biostudies-literature

Multivalency in a Dendritic Host-Guest System.

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| S-EPMC6458993 | biostudies-literature

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| S-EPMC9324901 | biostudies-literature

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