Multiply–linked cyclodextrin–aromatic hybrids: Caps, hinges and clips

For Peer Review Only Multiply–linked cyclodextrin–aromatic hybrids: caps, hinges and clips Journal: Journal of Carbohydrate Chemistry Manuscript ID LCAR-2019-0023.R1 Manuscript Type: Review Date Submitted by the Author: n/a Complete List of Authors: Neva, Tania; CSIC, Institute for Chemical Research Ortiz-Mellet, Carmen; University of Seville, Department of Organic Chemistry García Fernández, José; CSIC, Institute for Chemical Research Benito, Juan; CSIC, Institute for Chemical Research Keywords: self-assembling, host-guest, transition metal catalysis, supramolecular chemistry, capped cyclodextrins Note: The following files were submitted by the author for peer review, but cannot be converted to PDF. You must view these files (e.g. movies) online. Figure 2.cdx Scheme 1.cdx Scheme 2.cdx Scheme 3.cdx Scheme 4.cdx Scheme 5.cdx Scheme 6.cdx Scheme 8.cdx URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry For Peer Review Only 1 Multiply–linked cyclodextrin–aromatic hybrids: caps, hinges and clips. Tania Nevaa, Carmen Ortiz Melletb, José M. García Fernándeza and Juan M. Benitoa* aInstituto de Investigaciones Químicas (IIQ), CSIC - University of Seville, Seville, Spain; bDepartment of Organic Chemistry, Faculty of Chemistry, University of Seville, Seville, Spain Correspondence: Dr. J. M. Benito, Instituto de Investigaciones Químicas (IIQ), CSIC−University of Seville, Av. Americo Vespucio 49, 41092 Seville, Spain; email: [email protected] Page 1 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 2 Multiply–linked cyclodextrin–aromatic hybrids: caps, hinges and clips. The judicious combination of shaping and recognition elements in cage-type architectures represents a powerful strategy to access molecular devices with tailored receptor properties and controlled abilities to form supramolecular assemblies. Aromatic modules are particularly attractive for these endeavours: they can play the role of rigid walls to build permanent cavities, folding screens between preexisting compartments and/or act as functional components promoting noncovalent self-interactions as well as associations with third species, allowing several levels of organization to be implemented. The field of cyclodextrins has enormously benefitted from the amalgamation with aromatic building blocks to give birth to hybrids with a much broader spectrum of properties and applications. The progress in precision chemistry has further enabled the efficient preparation of multiply-linked cap, hinge or clip cyclodextrin-aromatic chimeras with unprecedented level of control, which has translated into new developments in fields like supramolecular catalysis, selfassembly or gene delivery. This review article focuses specifically in these type of compounds, highlighting the intimate relationship between structure, supramolecular properties and performance in the target application. Keywords: capped cyclodextrins; supramolecular chemistry; transition metal catalysis; host-guest; self-assembling Graphical abstract Page 2 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 3 Introduction The cyclomaltooligosaccharides (cyclodextrins, CDs) are iconic cage molecules that have been instrumental in the burst and development of supramolecular chemistry.[1] Their α-(1→4)-linked α-D-glucopyranosyl backbone features a truncated-cone toroidal shape that exhibits inner-outer amphiphilicity, enabling the inclusion of hydrophobic guest molecules on a size-fit basis (Figure 1). Upon confinement in the CD cavity, the properties of the guest (e.g. its fluorescence behavior, spectroscopic properties, stability, chemical reactivity or accessibility to enzymes or receptors) become altered, which have given rise to a broad variety of technological applications. The implementation of efficient methodologies for the functionalization of the hydroxyl groups in the native cyclodextrins through precision chemistry strategies has exponentially expanded the catalogue of available CD derivatives beyond the straight-jacketed hexa (αCD), hepta (βCD) and octamer (γCD) representatives.[2] Currently, tailored-made CDs can be accessed in single diastereomeric form with a precise orientation of functional elements, with the only limitation of one’s imagination.[3] Chemical elaboration allows, for instance, overcoming the limit of the internal cavity for molecular hosting, imparting catalytic activities, programming self-assembly or promoting the association with biomolecular partners. Aromatic appendages are particularly attractive for those channels: they can play the role of rigid walls and probe elements, conveying additional noncovalent interaction and sensing abilities and allowing several levels of organization to be implemented. In most reported examples, however, the aromatic component in aromatic-CD hybrids is attached to the cyclooligosaccharide core through a single position and retains substantial mobility, which limits accurate three-dimensional definition.[4] Multiply-linked derivatives with restricted conformational freedom, reachable after point-specific positioning of the components, are better suited for Page 3 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 4 precise control of receptor topology. Depending on the relative disposition of the anchoring points, “cap”-, “hinge”- and “clip”-like architectures with diverse degrees of flexibility have been reported. This review centers specifically on such kind of molecular nanosized hybrids, with a focus on the potential of aromatic modules to trigger conformational changes and self-assembling modes impacting the CD supramolecular and functional properties. Rather than a comprehensive discussion, we will comment on selected representative examples that highlight the vigor of the field. Note that capped CD dimers incorporating aromatic segments in the tethering arm are not covered here. For an all-inclusive information, the reader is addressed to excellent reviews and recent reports.[5] OH HO OH HO OH HO HO HO OH OH OHOH OO O O O HO HO OH OH OH OH OH OH HO n O OH O O HO HO O OH O HO HO OHO O OH HO O HO O OH OH O HO O OH OH O OH HO OH i. d. (Å) 4.7 - 5.2 6.0 - 6.4 7.5 - 8.3 CD CD (n = 1) CD (n = 2) CD (n = 3) o. d. (Å) 14.2 - 15.0 15.0 - 15.8 17.1 - 17.9 height (Å) 7.9 - 8.0 7.9 - 8.0 7.9 - 8.0 cyclodextrin (CD) Page 4 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 5 Figure 1. General structure and dimensions of native cyclodextrins (the acronyms i. d. and o. d. refer to inner and outer diameter, respectively). Doubly-linked heteroaromatic caps: metal chelation and catalysis The rigid structure of CDs, with hydroxyl groups regularly disposed at precise distances, provides a versatile framework for programming concerted metal chelation after point-selective functionalization. The more readily accessible primary positions have been generally targeted for these channels. In order to limit the conformational mobility, Matt, Armspach and coworkers developed synthetic methodologies, based in the use of tritylating reagents, to access diamines for the incorporation of capping heteroaromatic ligands doubly anchored at C-6 positions in I/II, I/III or I/IV relative disposition in either  or βCD.[6] In a pioneering work, these authors described the synthesis of the 2,2’-bipyridyl-capped αCDs 1 and 2. These hybrids exhibited distinct metal chelating properties that were governed by the orientation of the aromatic fragment: endo-oriented bipyridyl moieties preferentially stabilized metals with planar coordination geometry metals, such as Pd(II),[7] while the exo-oriented analog better adapted to octahedral metal centers, such as Ru(II),[8] (Scheme 1). Page 5 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 6 MeOMeO OMe OMe MeO H2N OMe NH2 OMe n or CD 6I,6IV-CD, 16I,6IV-CD, 26I,6IV-CD, 3 6I,6IV-CD, 3 m m + n = 4 or 5 (for - and CD, respectively) 6I,6III-CD, 4 6I,6III-CD, 4 6I,6IV-CD, 5 6I,6IV-CD, 5 NHN N N MeOMeO OMe OMe MeO O OMe O OMe n CD m m + n = 4 NH HN H2N H2N NaBH3CN HC(OEt)3 HCl Cl AuCl N N Cl N N ClOC COCl i) Et3N, tol, 80 ºC ii) [PdCl2] N N ClOC COCl i) Et3N, tol, 80 ºC ii) [Ru(bpy)2] planar-square 1:Pd coordination octahedral 2:Ru coordination N O O ii) FeCl2 i) trigonal-pyramidal 3:Fe coordination OO AcOH, tol, reflux 6I,6III-CD, 6; 6I,6IV-CD, 7 MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO Pd(II) Ru(II) Fe(II) Au N N HN O N O N N HN O NH O N N N Pd Cl (bpy)2 Ru Fe Cl Cl MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO H MeOMeO OMe OMe MeO H2N OMe NH2 OMe n or CD 6I,6IV-CD, 1 NN HN O N O 6I,6IV-CD, 2 NN HN O NH O N N N 6I,6IV-CD, 3 6I,6IV-CD, 3 m m + n = 4 or 5 (for - and CD, respectively) 6I,6III-CD, 4 6I,6III-CD, 4 6I,6IV-CD, 5 6I,6IV-CD, 5 NHN N N MeOMeO OMe OMe MeO O OMe O OMe n CD m m + n = 4 NH HN H2N H2N NaBH3CN HC(OEt)3 HCl Cl AuCl N N Cl N N ClOC COCl i) Et3N, tol, 80 ºC ii) [PdCl2] Pd Cl N N ClOC COCl i) Et3N, tol, 80 ºC ii) [Ru(bpy)2](bpy)2 Ru planar-square coordination octahedral coordination N O O ii) FeCl2 i) Fe Cl Cl trigonal-pyramidal coordination OO AcOH, tol, reflux 6I,6III-CD, 6; 6I,6IV-CD, 7 MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO MeOMeO OMe OMe MeO Page 6 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 7 Scheme 1. Different approaches to primary rim N-heterocyclic aromatic-capped CDs reported by Matt, Armspach and coworkers and their metal chelation capabilities (methoxyls at the primary rim were omitted for clarity in some of the structures). The same laboratory reported the synthesis of α and βCD derivatives equipped with a rigid pyridine-bisimine cap bridging the distal 6I and 6IV positions (3α and 3β). This architecture provided a suitable environment for trigonal bipyramidal chelation of Fe(II)[9] (Scheme 1), which is remarkable considering that in the absence of the CD scaffold the pyridine-bisimine motif affords octahedral Fe(II) complexes. The approach has been later extended to the installation of aromatic caps through 6I/6III and 6I/6IV unsymmetrical imine-enamine (4 and 5) and benzimidazole (6 and 7) bridges in a regioselective manner. The final compounds have induce inward-oriented nitrogen atomscoordination, offering new opportunities for conducting catalytic reactions in a highly crowded chiral environment.[10] The concept has been recently demonstrated for the asymmetric cycloisomerization of 1,6-enynes promoted by complexes of Au(I) and benzimidazolium carbene-capped CDs[11] (Scheme 1). Sollogoub and co-workers developed an efficient synthesis of N-heterocyclic carbene (NHC)-capped CD derivatives (8α and 8β) and of their complexes with group 11 transition metals, i.e. Cu(I), Ag(I) or Au(I), and investigated the striking effects of confinement of the metal inside the CD cavity in the chemical properties. A unique C- H···M coordination sphere was evidenced that served as insulation shield from electrode surfaces and governed the catalytic activity. Thus, the regioselectivity of the Au(I)-catalyzed cycloisomerization of 1,6-enynes reverted upon switching from α to βCD-based NHC ligands.[12] Similar CD ring size effects on the regioselectivity were observed for the Cu(I)-catalyzed hydroboration reaction, which led the authors to Page 7 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 8 proposed different catalytic pathways for αCD- and βCD-derived NHC/Cu(I) complexes[13] (Scheme 2). HO OBn OH BnO BnO OBn 1 or 2 or CD i) MsCl ii) N N H OBn BnO BnO OBn 1 or 2 or CD N NCl OBn BnO BnO OBn 1 or 2 N N Ag2O, CuCl or AuCl MeO2C CO2Me [8·M]+·Cl- M = Cu, Ag, Au [8·Au]+·Cl- MeO2CCO2Me MeO2CCO2Me MeO2CCO2Me [8·Au]+·Cl- 1 : 0.65 : 0 63-52% ++ DCM 1 : 0 : 3.3 A B C 82-71% tBuOK, MeOH O H B O [8·Cu]+·Cl- [8·Cu]+·Cl- 0.94 : 0.06 0.12 : 0.88 MeO BO O MeO B O O MeO + BnO BnOBnO OBnOBn OBn OBn BnO BnOBnO OBnOBn OBn OBn BnO BnOBnO OBnOBn OBn OBn 6I,6IV-CD, 8 6I,6IV-CD, 8 Cl HO OBn OH BnO BnO OBn 1 or 2 or CD i) MsCl ii) N N H OBn BnO BnO OBn 1 or 2 or CD N NCl OBn BnO BnO OBn 1 or 2 N N Cl Ag2O, CuCl or AuCl MeO2C CO2Me [8·M]+·Cl-; M = Cu, Ag, Au 6I,6IV-CD, 8  6I,6IV-CD, 8 [8·Au]+·Cl- MeO2CCO2Me MeO2CCO2Me MeO2CCO2Me [8·Au]+·Cl- 1 : 0.65 : 0 63-52% ++ DCM 1 : 0 : 3.3 A B C 82-71% tBuOK, MeOH O H B O [8·Cu]+·Cl- [8·Cu]+·Cl- 0.94 : 0.06 0.12 : 0.88 MeO BO O MeO B O O MeO + BnO BnOBnO OBnOBn OBn OBn BnO BnOBnO OBnOBn OBn OBn BnO BnOBnO OBnOBn OBn OBn Scheme 2. (A) Synthesis of NHC-capped CDs 8α and 8β described by Sollogoub and coworkers and their performance in 1,6-enyne cycloisomerization (B) and hydroboration reactions (C) catalysed by Au(I) and Cu(I), respectively. Page 8 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 15 O MeO MeO OMe O O O O OMe O O MeO MeO OMe O O O OMe OMe MeO O OMe OMe MeO O O OMe OMe MeO O n O HO HO OH O O O O OH O O HO HO OH O O O OH OH HO O OH OH HO O O OH OH HO O n -, -, or CD LDA, DMSO 28-33% Br Br MeI, NaH DMF O MeO MeO OMe O O HO HO OMe O O MeO MeO OMe O O O OMe OMe MeO O OMe OMe MeO O O OMe OMe MeO O n O MeO MeO OMe O O O O OMe O O MeO MeO OMe O O O OMe OMe MeO O OMe OMe MeO O O OMe OMe MeO O n Br Br NaH, DMF hydroxyls in the same Glc unit Pd/C, H2 HCO2H 28-30 n = 1, 19,22,25, and 28 n = 2, 20,23,26, and 29 n = 3, 21,24,27, and 30 22-24 19-21 25-27 Scheme 6. Synthesis of hinged-type cyclodextrin-aromatic hybrids by direct 2I,3I-O-(oxylylenation) of native CDs described by Ortiz Mellet, García Fernández and coworkers. The 2I,3I-O-(o-xylylene)-equipped permethylated CD derivatives 22-24 exhibited negative solubility temperature coefficients in water: when heated, clear (25 °C) solutions became immediately turbid, returning to the limpid original state upon cooling. This was ascribed to reversible dimerization processes: in the dimer state, the hydrophobic aromatic moiety is likely sandwiched between the two self-assembling CD monomers, becoming shielded from the bulk. This arrangement facilitates solvation and preventing unspecific clusterization at low temperatures, whereas heating results in dimer disruption, uncovering of the aromatic ring and precipitation. The thermodynamic parameters for the monomer-to-dimer equilibrium was extensively characterized by steady-state and time-resolved fluorescence techniques (based on the fluorescence of the bidentate xylylene moiety), NMR and computational studies (molecular mechanics Page 15 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 16 and molecular dynamics; MM and MD). The data were consistent with a restricted mobility of the xylylene hinge, which can adopt close and open conformations relative to the CD cavity, but do not undergo self-inclusion. The formation of head-to-head (HH) dimers in semi-open conformation is then strongly favored.[36] A similar behavior was observed for α, β and γCD derivatives incorporating the 2I,3I-O-(1,8- dimethylnaphthylene) hinge 28-30, obtained from the corresponding diols by reaction with 1,8-dibromomethylnaphthalene[37] (Scheme 6). Interestingly, the presence of the aromatic hinge in the CDs enhances the 1:1 association constants towards hydrophobic guests such as octyl β-D-glucopyranoside or methyl 2-naphthalenecarboxylate (2MN; a fluorescent probe sensitive to medium polarity), by about three-fold as compared with the fully methylated hosts, by providing additional favorable contacts. It is worth noting that inclusion of the guest requires dimer disruption, which could be used for the spatiotemporal control of the self-assembling properties (Figure 2). OO OO O O O O < T > T Kdimer 200 M-1 insoluble monomer soluble dimer OO OH HO HO OH octyl -D-glucopyranoside CO2Me 2MN K1:1 (for 23, M-1) 350 281 OMe MeO OMe OMeOMe OMe 23 OMe OMe MeO OMe OMe OMe OMe OMe MeO OMe MeO MeO MeO MeO OMe OMe Figure 2. Schematic representation of the conformational and aggregation equilibria for 2I,3I-O-(o-xylylenated)-βCD 23. Page 16 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 17 The possibility of controlling the propensity of CD derivatives to form HH- dimers in aqueous environments offers new opportunities for programming reversible hierarchical processes requiring the antiparallel orientation of functional elements located at the primary face of the cyclooligosaccharide platform. The co-assembly of cyclodextrin-based multihead/multitail amphiphiles with nucleic acids to afford nanocomplexes with transfectious capabilities represents an archetypic example.[38,39] Nanometric molecular gene delivery systems (molecular nanoparticle-based vectors)[40,41] of this family spontaneously form bilayers between quasi-parallel nucleic acid chains (DNA or RNA) by the interplay of electrostatic interactions between the cationic clusters and the polyphosphate backbone[42] and hydrophobic interactions involving the lipophilic domains,[43] concertedly leading to desolvation and compaction of the genetic material. HH-dimers with cationic clusters oriented in opposite directions emulate the smallest structural element of a bilayer and are therefore pre-organized to undergo nucleic acid-templated nanocondensation[44] (Figure 3). Figure 3. Schematic representation of the process leading to nucleic acid condensation in the presence of polycationic CD amphiphiles emphasizing on the relevance of the spontaneous formation of CD amphiphile bilayers. Page 17 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 18 As a proof of concept, Ortiz Mellet, Mendicuti, García Fernández and coworkers prepared the polycationic 2I,3I-O-(o-xylylene)-βCD derivatives 32 and 34 by xylylenation of the per-(C-6)-azido βCD followed either by reduction of the azido groups or by copper(I)-catalyzed azide-alkyne coupling (CuAAC) reaction with the propargyl-functionalized amine dendron 33 and final deprotection[45] (Scheme 7). NMR, fluorescent decay measurements and computational studies supported the existence of pH-dependent dimerization equilibria in water: whereas the dimers are rather stable at neutral pH, decreasing the pH results in higher protonation degrees of the polyamine domains and, consequently, stronger coulombic repulsion of the CD constituents. Upon formulation with plasmid DNA (pDNA), multilayer co-assemblies endowed with pH- responsiveness were obtained. This is conceptually very interesting for applications in gene therapy, since the weakening of the dimers after nanoparticle cell uptake destabilizes the whole CD-DNA supramolecular edifice, facilitating endosome escape and DNA cargo release. Indeed, evaluation of the transfection capabilities in COS-7 (renal epithelial green monkey) cells, using a luciferase-encoding reporter pDNA, afforded efficiencies that paralleled (32) or overpassed by 10-fold that of the nonviral vector gold standard polyethyleneimine [45]. Page 18 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 19 Scheme 7. Synthesis of polycationic 2I,3I-O-(o-xylylene)-βCD derivatives 32 and 34 and proposed mechanism for the pH-sensitive hierarchical condensation and release of DNA. At neutral pH, the xylylene group promotes dimerization through hydrophobic interactions, preorganizing the system for the next DNA condensation step. Acidification leads to increased electrostatic repulsion, destabilizing the condensate and facilitating DNA release. Cyclic ether aromatic clips: control over molecular topology Yamada and coworkers developed an elegant strategy to achieve completely β-selective glycosylation by using a glycosyl fluoride donor bearing an o-xylylene bridge between the 3-O and 6-O positions of D-glucopyranose.[46] The rationale behind is that the rigid tether connecting the nonconsecutive positions in the monosaccharide forces a distorted conformation of the six-membered ring that determines the stereochemical outcome of the reaction. Moving to the field of cyclodextrins, Ortiz Mellet, Mendicuti, García Page 19 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 20 Fernández and coworkers conceived that aromatic “clips” could similarly be inserted between nonconsecutive hydroxyls to force a conformational change in the cyclooligosaccharide macroring, thereby modifying the topology of the cavity.[47] Starting from the βCD diol derivative 35, accessed by regioselective bis-demethylation of permethylated βCD with diisopropylaluminum hydride (DIBAL·H) following the methodology of Sollogoub and coworkers,[48] the reaction with 1,2- or 1,3- dibromomethylbenzene, afforded the corresponding 2I,3II-di-O-(o- or m-xylylene)-βCD derivatives 36 and 37, respectively (Scheme 8). As predicted from theoretical calculations, the o-xylylene “clipped” isomer 36 preserved the 4C1 chair conformation of the glucopyranosyl residues and the toroidal shape characteristic of CDs. Sharply differently, the m-xylylene clip in 37 provoked a shift to the 1C4 conformation in the (O- 3)-substituted monosaccharide residue, which results in a substantial alteration of the overall shape of the host to an elliptic geometry. O MeO MeO OMe O7 O O DIBAL·H toluene O HO MeO O OMe O MeO MeO O OMe O MeO MeO OMe O OMe OMe OO MeO O OOMe OMe MeO O OMe OMe MeO O OMe OH O MeO O 35 O MeO O OMe O O OMe O MeO O O O MeO O OMe O O OMe O MeO O O O MeO O OMe O O OMe O MeO OO O OMe O MeO OO OOMe MeO Br Br Br Br Br Br Br Br NaH, DMF NaH, DMF NaH, DMF 36 37 38 39 NaH, DMF Page 20 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 21 Scheme 8. Synthesis of O-2I,O-3II-xylylene- (36 and 37) and dimethylnaphthyleneclipped (38 and 39) βCD derivatives. The MM-optimized 3D-structures of 36 and 37 (secondary rim view) of their structures are depicted at the right hand side. Prearranging the CD topology through aromatic clipping enables the control over the inclusion properties. Thus, circular dichroism experiments established that the o-xylylene module in 36 adopts a semi-open conformation that permits the inclusion of hydrophobic molecules fitting the size of the βCD cavity. The guest can additionally benefit from favorable contacts with the aromatic clip in the complex, as confirmed for adamantane-1-carboxylate (AC). Dissimilarly, the elliptic cavity of 37 is unable to host globular molecules, even though the m-xylylene moiety adopts a fully open arrangement, selecting instead planar guests such as methyl 2-naphthoate. Fluorescence decay measurements and computational calculations further evidenced a direct relationship between molecular shape and self-assembling behavior: compound 36 formed an HH-dimer in water solution whereas the conformationally distorted analogue 37 existed in monomeric form at any concentration.[47] The potential of aromatic clips to modulate the self-assembling properties of CDs has been further demonstrated by preparing the O-2I,O-3II-linked 1,8- and 2,3- dimethylnaphthylene derivatives 38 and 39, respectively. In both cases the conformation of the glucopyranosyl units and the CD macroring remain essentially unaltered. However, the relative orientation of the aromatic platform significantly differs: the 1,8-dimethylnaphthalene module in 38 adopts a rather rigid open conformation whereas the more flexible 2,3-dimethylnaphthalene appendage in 39 can accommodate a semi-open arrangement. Both compounds form rather stable HH-dimers in water solution, but whereas the aromatic motifs act as extension walls in the case of 38-dimer, they behave as folding screens between the secondary rims of the monomer Page 21 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 22 constituents in the case of 39-dimer. Remarkably, the dimer architecture has a strong impact in the inclusion capabilities. Thus, the AC guest was found to enter the 38-dimer extended cavity through the bulk-exposed βCD narrower rim to form a ternary complex AC/38-dimer. In other words, 38-dimer can accept hydrophobic cargos while preserving the self-assembled structure. Contrarily, inclusion of AC triggered 39-dimer disruption to give the bimolecular AC/39 complex species (Figure 4). The possibility of implementing different supramolecular organization levels (e.g., self-assembly and/or inclusion and/or spatiotemporal controlled dissociation) with aromatic clips offers then a rational strategy to program the behavior of CD-based devices in biological environments for (bio)molecular encapsulation and controlled release.[49] Figure 4. Schematic representation of the structure of AC/38 and AC/39 complexes illustrating the disparate molecular inclusion dimer formation capabilities imposed by their corresponding dimethylnaphthalene appendages. Page 22 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 23 Concluding remarks The ensemble of contributions commented in the above sections illustrates the potential of strategies based in combining CD hosts and aromatic modules to generate precise molecular topologies and programming several levels of supramolecular organization. Beyond predefining interactions with target guest for sensing purposes, aromatic moieties can drive self-assembly as well as co-assembly with biomolecular partners to afford nanocomplexes capable of performing specific tasks. Polyfunctional CD- aromatic hybrids can further be designed to reversibly self-arrange into stimuli responsive multivalent constructs with predictable orientations and densities of the key appended motifs. The current applications have focused mainly in supramolecular catalysis[50] and molecular vectors for non-viral gene delivery[51] because of the critical dependence of the efficiency of these processes on molecular and supramolecular preorganization.[52] Cyclodextrins have been broadly used to synthesize multivalent ligands in other research areas such as carbohydrate-protein interactions,[53] poreforming toxin blockers[54] or enzyme inhibition[55] that are also expected to benefit from similar approaches. New developments will certainly arise in the near future from the intimate merging of cyclodextrin and aromatic units in purpose-conceived hybrid architectures. Disclosure statement No potential conflict of interest was reported by the authors. Page 23 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 24 Funding The authors acknowledge the financial support of the Spanish Ministerio de Economía y Competitividad (contract numbers CTQ2015-64425-C2-1-R and SAF2016-76083-R), the Junta de Andalucía (contract number FQM2012-1467) and the European Regional Development Funds (FEDER and FSE). TN acknowledges the Junta de Andalucía for a doctoral fellowship. References [1] Crini, G. Review: A History of Cyclodextrins. Chem. Rev. 2014, 114, 10940-10975. DOI: 10.1021/cr500081p. [2] Benito, J.M.; García Fernández, J.M. Cyclodextrin Chemistry via Selective Hydroxyl Group Manipulations. In Protecting Groups: Strategies and Applications in Carbohydrate Chemistry; Vidal, S., Ed. Wiley-VCH: Weinheim, Germany, 2019; pp. 371-393. [3] Wang, B.; Zaborova, E.; Guieu, S.; Petrillo, M.; Guitet, M.; Blériot, Y.; Ménand, M.; Zhang, Y.; Sollogoub, M. Site-Selective Hexa-Hetero-Functionalization of α-Cyclodextrin an Archetypical C6-Symmetric Concave Cycle. Nat. Commun. 2014, 5, 5354. DOI: 10.1038/ncomms6354. [4] Gamieldien, M.R.; Maestre, I.; Jaime, C.; Naidoo, K.J. Optimal Configurations of “Capped” β-Cyclodextrin Dimers in Water Maximise Hydrophobic Association. ChemPhysChem 2010, 11, 452-459. DOI: 10.1002/cphc.200900541. [5] (a) Engeldinger, E.; Armspach, D.; Matt, D. Capped Cyclodextrins. Chem. Rev. 2003, 103, 4147-4173. DOI: 10.1021/cr030670y. (b) Ogoshi, T.; Harada, A. Chemical Sensors Based on Cyclodextrin Derivatives. Sensors 2008, 8, 4961- 4982; DOI: 10.3390/s8084961. (c) Ito, S.; Kogame, C.; Akashi, M.; Kida, T. Facile Synthesis of Novel Cyclodextrin Dimer Capsules and Their Inclusion Ability Towards Aromatic Guests in a Nonpolar Solvent. Tetrahedron Lett. 2016, 57, 5243-5245. DOI: 10.1016/j.tetlet.2016.10.039. (d) Asahara, C.; Iwamoto, T.; Akashi, M.; Shigemitsu, H.; Kida, T. Effective Guest Inclusion by Page 24 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 31 Secondary Face. J. Phys. Chem. B 2013, 117, 5472-5485. DOI: 10.1021/jp400784t. [38] (a) Ortiz Mellet, C.; Benito, J.M.; García Fernández, J.M. Preorganized, Macromolecular, Gene-Delivery Systems. Chem. Eur. J. 2010, 16, 6728-6742. DOI: 10.1002/chem.201000076. (b) Ortiz Mellet, C.; García Fernández, J.M.; Benito, J.M. Cyclodextrin-Based Gene Delivery Systems. Chem. Soc. Rev. 2011, 40, 1586-1608. DOI: 10.1039/c0cs00019a. (c) Ortiz Mellet, C.; García Fernández, J.M.; Benito, J.M. Glycotransportes for gene delivery. In Carbohydrate Chemistry. Chemical and Biological Approaches; Rauter, A.P., Lindhorst, T.K., Eds.; Royal Society of Chemistry, Cambridge, 2012; Vol. 38, pp 338-375. ISBN: 978-1-84973-439-4. (d) García Fernández, J.M.; Benito, J.M.; Ortiz Mellet, C. Cyclodextrin-Scaffolded Glycotransporters for Gene Delivery. Pure Appl. Chem. 2013, 85, 1825-1845. DOI: 10.1351/PAC-CON-12- 10-13. (e) Ortiz Mellet, C.; García Fernández, J.M.; Benito, J.M. Cyclodextrins for Pharmaceutical and Biomedical Applications. In Supramolecular Systems in Biomedical Fields; Schneider, H.-J. Ed.; Royal Society of Chemistry, Cambridge, 2013; Vol. 13, pp 94-139. ISBN: 978-1-84973-658-9. (f) Latxague, L.; Gaubert, A.; Barthélémy, P. Recent Advances in the Chemistry of Glycoconjugate Amphiphiles. Molecules 2018, 23, 89; DOI: 10.3390/molecules23010089. [39] (a) Díaz-Moscoso, A.; Patricia Balbuena, P.; Gómez-Garcia, M.; Ortiz Mellet, C.; Benito, J.M.; Le Gourriérec, L.; Di Giorgio, C.; Vierling, P.; Mazzaglia, A.; Micali, N.; et al. Rational Design of Cationic Cyclooligosaccharides as Efficient Gene Delivery Systems. Chem. Commun. 2008, 2001-2003. DOI: 10.1039/b718672j. (b) Ortega-Caballero, F.; Ortiz Mellet, C.; Le Gourriérec, L.; Guilloteau, N.; Di Giorgio, C.; Vierling, P.; Defaye, J.; García Fernández, J.M. Tailoring-Cyclodextrin for DNA Complexation and Delivery by Homogeneous Functionalization at the Secondary Face. Org. Lett. 2008, 10, 5143-5146. DOI: 10.1021/ol802081z. (c) Méndez-Ardoy, A.; Urbiola, K.; Aranda, C.; Ortiz Mellet, C.; García Fernández, J.M.; Tros de Ilarduya, C.; Polycationic Amphiphilic Cyclodextrin-Based Nanoparticles for Therapeutic Gene Delivery. Nanomedicine 2011, 6, 1697-1707. DOI:10.2217/NNM.11.59. (d) Bienvenu, C.; Martínez, A.; Jiménez Blanco, J.L.; Di Giorgio, C.; Vierling, P.; Ortiz Mellet, Page 31 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 32 C.; Defaye, J.; García Fernández, J.M. Polycationic Amphiphilic Cyclodextrins as Gene Vectors: Effect of The Macrocyclic Ring Size on the DNA Complexing and Delivery Properties. Org. Biomol. Chem. 2012, 10, 5570-5581. DOI: 10.1039/c2ob25786f. (e) Symens, N.; Méndez-Ardoy, A.; Díaz-Moscoso, A.; Sánchez-Fernández, E.; Remaut, K.; Demeester, J.; García Fernández, J.M.; De Smedt, S. C.; Rejman, J. Efficient Transfection of Hepatocytes Mediated by mRNA Complexed to Galactosylated Cyclodextrins. Bioconjugate Chem. 2012, 23, 1276-1289. DOI: 10.1021/bc3001003. (f) Martínez, A.; Bienvenu, C.; Jiménez Blanco, J.L.; Vierling, P.; Ortiz Mellet, C.; García Fernández, J.M.; Di Giorgio, C. Amphiphilic Oligoethyleneimine-β-Cyclodextrin “Click” Clusters for Enhanced DNA Delivery. J. Org. Chem. 2013, 78, 8143-8148. DOI: 10.1021/jo400993y. (g) Aranda, C.; Urbiola, K.; Méndez Ardoy, A.; García Fernández, J.M.; Ortiz Mellet, C.; Tros de Ilarduya, C. Targeted gene delivery by new folate–polycationic amphiphilic cyclodextrin–DNA nanocomplexes in vitro and in vivo. Eur. J. Pharm. Biopharm. 2013, 85, 390-397. DOI: 10.1016/j.ejpb.2013.06.011. (h) Méndez-Ardoy, A.; Díaz-Moscoso, A.; Ortiz Mellet, C.; Di Giorgio, C.; Vierling, P.; Benito, J.M.; García Fernández, J.M. Harmonized Tuning of Nucleic Acid and Lectin Binding Properties with Multivalent Cyclodextrins for Macrophage-Selective Gene Delivery. RSC Adv. 2015, 5, 76464-76471. DOI: 10.1039/c5ra16087a. (i) Gallego-Yerga, L.; Lomazzi, M.; Franceschi, V.; Sansone, F.; Ortiz Mellet, C.; Donofrio, G.; Casnati, A.; García Fernández, J.M. Cyclodextrin- and Calixarene-Based Polycationic Amphiphiles as Gene Delivery Systems: A Structure–Activity Relationship Study. Org. Biomol. Chem. 2015, 13, 1708-1723. DOI: 10.1039/c4ob02204a. (j) Guilloteau, N.; Bienvenu, C.; Charrat, C.; Jiménez Blanco, J.L.; Díaz-Moscoso, A.; Ortiz Mellet, C.; García Fernández, J.M.; Vierling, P.; Di Giorgio, C. Cell Uptake Mechanisms of Glycosylated Cationic pDNA–Cyclodextrin Nanoparticles. RSC Adv., 2015, 5, 29135-29144. DOI: 10.1039/c5ra00964b. (k) Martínez-Negro, M.; Caracciolo, G.; Palchetti, S.; Pozzi, D.; Capriotti, A.L.; Cavaliere, C.; Laganà, A.; Ortiz Mellet, C.; Benito, J.M.; García Fernández, J.M.; et al. Biophysics and Protein Corona Analysis of Janus Cyclodextrin-DNA Nanocomplexes. Efficient Cellular Transfection on Page 32 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 33 Cancer Cells. Biochim. Biophys. Acta Gen. Subj. 2017, 1861, 1737-1749. DOI: 10.1016/j.bbagen.2017.03.010. [40] Jiménez Blanco, J.L.; Benito, J.M.; Ortiz Mellet, C.; García Fernández, J.M. Molecular Nanoparticle-Based Gene Delivery Systems. J. Drug Deliv. Sci. Technol. 2017, 42, 18-37. DOI: 10.1016/j.jddst.2017.03.012. [41] (a) Jiménez Blanco, J.L.; Ortega-Caballero, F.; Blanco-Fernández, L.; Carmona, T.; Marcelo, G.; Martínez-Negro, M.; Aicart, E.; Junquera, E.; Mendicuti, F.; Tros de Ilarduya, C.; et al. Trehalose-Based Janus Cyclooligosaccharides: the “Click” Synthesis and DNA-Directed Assembly into pH-Sensitive Transfectious Nanoparticles. Chem. Commun. 2016, 52, 10117-10120. DOI: 10.1039/c6cc04791b. (b) Manzanares, D.; Araya-Durán, I.; Gallego-Yerga, L.; Játiva, P.; Márquez-Miranda, V.; Canan, J.; Jiménez Blanco, J.L.; Ortiz Mellet, C.; González-Nilo, F.D.; García Fernández, J.M. et al. Molecular Determinants for Cyclooligosaccharide-Based Nanoparticle Mediated Effective siRNA Transfection. Nanomedicine 2017, 12, 1607-1621. DOI: 10.2217/nnm-2017- 0123. [42] (a) Przybylski, C.; Benito, J.M.; Bonnet, V.; Ortiz Mellet, C.; García Fernández, J.M. Deciphering of Polycationic Carbohydrate Based Non-Viral Gene Delivery Agents by ESI-LTQ-Orbitrap Using CID/HCD Pairwise Tandem Mass Spectrometry. RSC Adv. 2016, 6, 78803-78817. DOI: 10.1039/c6ra14508f. (b) Przybylski, C.; Benito, J.M.; Bonnet, V.; Ortiz Mellet, C.; García Fernández, J.M. Toward a Suitable Structural Analysis of Gene Delivery Carrier Based on Polycationic Carbohydrates by Electron Transfer Dissociation Tandem Mass Spectrometry. Anal. Chim. Acta 2016, 948, 62-72. DOI: 10.1016/j.aca.2016.11.001. (c) Przybylski, C.; Benito, J.M.; Bonnet, V.; Ortiz Mellet, C.; García Fernández, J.M. Revealing Cooperative Binding of Polycationic Cyclodextrins with DNA Oligomers by Capillary Electrophoresis Coupled to Mass Spectrometry. Anal. Chim. Acta 2018, 1002, 70-81. DOI: 10.1016/j.aca.2017.11.034. [43] Pflueger, I.; Charrat, C.; Ortiz Mellet, C.; García Fernández, J.M.; Di Giorgio, C.; Benito, J.M. Cyclodextrin-Based Facial Amphiphiles: Assessing the Impact of the Hydrophilic–Lipophilic Balance in the Self-Assembly, DNA complexation Page 33 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 34 and Gene delivery Capabilities. Org. Biomol. Chem. 2016, 14, 10037-10049. DOI: 10.1039/c6ob01882c. [44] (a) Gallego-Yerga, L.; Blanco-Fernández, L.; Urbiola, K.; Carmona, T.; Marcelo, G.; Benito, J.M.; Francisco Mendicuti, M.; Tros de Ilarduya, C.; Ortiz Mellet, C.; García Fernández, J.M. Host–Guest-Mediated DNA Templation of Polycationic Supramolecules for Hierarchical Nanocondensation and the Delivery of Gene Material. Chem. Eur. J. 2015, 21, 12093-12104. DOI:10.1002/chem.201501678. (b) Gallego-Yerga, L.; Benito, J.M.; Blanco- Fernández, L.; Martínez-Negro, M.; Vélaz, I.; Aicart, E.; Junquera, E.; Ortiz Mellet, C.; Tros de Ilarduya, C.; García Fernández, J.M. Plasmid-Templated Control of DNA–Cyclodextrin Nanoparticle Morphology through Molecular Vector Design for Effective Gene Delivery. Chem. Eur. J. 2018, 24, 3825-3835. DOI: 10.1002/chem.201705723. [45] Gallego-Yerga, L.; González-Álvarez, M.J.; Mayordomo, N.; Santoyo-González, F.; Benito, J.M.; Ortiz Mellet, C.; Mendicuti, F.; García Fernández, J.M. Dynamic Self‐Assembly of Polycationic Clusters Based on Cyclodextrins for pH‐Sensitive DNA Nanocondensation and Delivery by Component Design. Chem. Eur. J. 2014, 22, 6622-6627. DOI: 10.1002/chem.201402026. [46] Okada, Y.; Asakura, N.; Bando, M.; Ashikaga, Y.; Yamada, H. Completely β- Selective Glycosylation Using 3,6-O-(o-Xylylene)-Bridged Axial-Rich Glucosyl Fluoride. J. Am. Chem. Soc. 2012, 134, 6940-6943. DOI: 10.1021/ja301480g. [47] Neva, T.; Carmona, T.; Benito, J.M.; Przybylski, C.; Ortiz Mellet, C.; Mendicuti, F.; García Fernández, J.M. Xylylene Clips for the Topology-Guided Control of the Inclusion and Self-Assembling Properties of Cyclodextrins. J. Org. Chem. 2018, 83, 5588-5597. DOI: 10.1021/acs.joc.8b00602. [48] Xiao, S.; Yang, M.; Sinaÿ, P.; Blériot, Y.; Sollogoub, M.; Zhang, Y. Diisobutylaluminium Hydride (DIBAL‐H) Promoted Secondary Rim Regioselective Demethylations of Permethylated β‐Cyclodextrin: A Mechanistic Proposal. Eur. J. Org. Chem. 2010, 1510-1516. DOI: 10.1002/ejoc.200901230. [49] Neva, T.; Carmona, T.; Benito, J.M.; Przybylski, C.; Ortiz Mellet, C.; Mendicuti, F.; García Fernández, J.M. Dynamic Control of the Self-Assembling Properties of Cyclodextrins by the Interplay of Aromatic and Host-Guest Interactions. Front. Chem. 2019, 7, 72, DOI: 10.3389/fchem.2019.00072. Page 34 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 35 [50] Mouarrawis, V.; Plessius, R.; van der Vlugt, J.I.; Reek, J.N.H. Confinement Effects in Catalysis Using Well-Defined Materials and Cages. Front. Chem. 2018, 6, 623. doi: 10.3389/fchem.2018.00623 [51] Stoffelen, C.; Huskens, J. Soft Supramolecular Nanoparticles by Noncovalent and Host–Guest Interactions. Small 2016, 12, 96-119. DOI: 10.1002/smll.201501348. [52] (a) Singh, R.P.; Hidalgo, T.; Cazade, P.-A.; Darcy, R.; Cronin, M.F.; Dorin, I.; O’Driscoll, C.M.; Thompson, D. Self-Assembled Cationic β-Cyclodextrin Nanostructures for siRNA Delivery. Mol. Pharmaceutics, 2019, 16, 1358-1366. DOI: 10.1021/acs.molpharmaceut.8b01307. (b) Evenou, P.; Rossignol, J.; Pembouong, G.; Gothland, A.; Colesnic, D.; Barbeyron, R.; Rudiuk, S.; Marcelin, A.-G.; Ménand, M.; Baigl, D. et al. Bridging β-Cyclodextrin Prevents Self-Inclusion, Promotes Supramolecular Polymerization, and Promotes Cooperative Interaction with Nucleic Acids. Angew. Chem. Int. Ed. 2018, 57, 7753-7758. DOI: 10.1002/anie.201802550. (c) Minnaert, A.-K.; Dakwar, G.R.; Benito, J.M.; García Fernández, J.M.; Ceelen, W.; De Smedt, S.C.; Remaut, K. High-Pressure Nebulization as Application Route for the Peritoneal Administration of siRNA Complexes. Macromol. Biosci. 2017, 17, 1700024. DOI: 10.1002/mabi.201700024. (d) Remaut, K.; De Clercq, E.; Andries, O.; Rombouts, K., Van Gils, M.; Cicchelero, L.; Vandenbussche, I.; Van Praet, S.; Benito, J.M.; García Fernández, J.M. et al. Aerosolized Non-viral Nucleic Acid Delivery in the Vaginal Tract of Pigs. Pharm. Res. 2016, 33, 384-394. DOI: 10.1007/s11095-015-1796-x. [53] (a) Martínez, A.; Ortiz Mellet, C.; García Fernández, J.M. Cyclodextrin-Based Multivalent Glycodisplays: Covalent and Supramolecular Conjugates to Assess Carbohydrate-Protein Interactions. Chem. Soc. Rev. 2013 42, 4746-4773. DOI: 10.1039/c2cs35424a. (b) Jiménez Blanco, J.L.; Ortiz Mellet, C.; García Fernández, J.M. Multivalency in Heterogeneous Glycoenvironments: Hetero- Glycoclusters, -Glycopolymers and -Glycoassemblies. Chem. Soc. Rev. 2013, 42, 4518-4531. DOI: 10.1039/C2CS35219B. [54] (a) Karginov, V.A. Cyclodextrin Derivatives as Anti-Infectives. Curr. Opin. Pharmacol. 2013, 13, 717-725. DOI: 10.1016/j.coph.2013.08.007. (b) Díaz- Moscoso, A.; Méndez-Ardoy, A.; Ortega-Caballero, F.; Benito, J.M.; Ortiz Page 35 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 36 Mellet, C.; Defaye, J.; Robinson, T.M.; Yohannes, A.; Karginov, V.A.; García- Fernández, J.M. Symmetry Complementarity-Guided Design of Anthrax Toxin Inhibitors Based on β-Cyclodextrin: Synthesis and Relative Activities of Face- Selective Functionalized Polycationic Clusters. ChemMedChem 2011, 6, 181- 192. DOI: 10.1002/cmdc.201000419. [55] (a) García Fernández, J.M.; Nierengarten, J.-F.; Ortiz Mellet, C. Multivalency as an Action Principle in Multimodal Lectin Recognition and Glycosidase Inhibition: A Paradigm Shift Driven by Carbon-Based Glyconanomaterials. J. Mater. Chem. B 2017, 5, 6428-6436. DOI: 10.1039/c7tb00860k. (b) García-Moreno, M.I.; Ortega-Caballero, F.; Rísquez-Cuadro, R.; Ortiz Mellet, C.; García Fernández, J.M. The Impact of Heteromultivalency in Lectin Recognition and Glycosidase Inhibition: An Integrated Mechanistic Study. Chem. Eur. J. 2017, 23, 6295-6304. DOI: 10.1002/chem.201700470. (c) Decroocq, C.; Rodriguez- Lucena, D.; Russo, V.; Mena Barragan, T.; Ortiz Mellet, C.; Compain, P. The Multivalent Effect in Glycosidase Inhibition: Probing the Influence of Architectural Parameters with Cyclodextrin‐based Iminosugar Click Clusters. Chem. Eur. J. 2011, 17, 13825-13831. DOI: 10.1002/chem.201102266. Page 36 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only multiply-linked CD-aromatic hybrids selfassembling host-guest chemistry catalysis structural scaffold M M Page 37 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only OH HO OH HO OH HO HO OH OH OO O O O HO HO OH OH OH OH OH HO OH n cyclodextrin (CD) Page 38 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only DNA paCD lipid-like� bilayer hydrophobic� compaction electrostatic� interaction Page 39 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Peer Review Only 38-dimer:AC 39:AC complexes the�extended�38-dimer� cavity�accommodates�AC. AC�accesses�the�cavity� through�the�narrower� rim AC 38-dimer 39-dimer type�I type�II 39-dimer�dissociates�prior�AC� inclusion. AC�can�adopt�both�(type�I�and�II)� orientations�into�the�monomer�cavity Page 40 of 41 URL: http://mc.manuscriptcentral.com/lcar Email: [email protected] Journal of Carbohydrate Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60