Articoli di riviste: "Macrocycles"

1

Abdelraheem, Eman, Shabnam Shaabani, and Alexander Dömling. "Artificial Macrocycles." Synlett 29, no. 09 (May 7, 2018): 1136–51. http://dx.doi.org/10.1055/s-0036-1591975.

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Artificial macrocycles recently became popular as a novel research field in drug discovery. As opposed to their natural twins, artificial macrocycles promise to have better control on synthesizability and control over their physicochemical properties resulting in druglike properties. Very few synthetic methods allow for the convergent, fast but diverse access to large macrocycles chemical space. One synthetic technology to access artificial macrocycles with potential biological activity, multicomponent reactions, is reviewed here, with a focus on our own work. We believe that synthetic chemists have to acquaint themselves more with structure and activity to leverage the design aspect of their daily work.1 Introduction2 Macrocycle Properties and Receptor Binding3 Synthetic Approaches towards Artificial Macrocycles Using MCR4 Design Rules for Membrane Crossing Macrocycles5 Design Rules for Libraries of Macrocycles6 Computational Macrocyclic Methods7 Future View

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Singh, Kartikey, and Rama Pati Tripathi. "An Overview on Glyco-Macrocycles: Potential New Lead and their Future in Medicinal Chemistry." Current Medicinal Chemistry 27, no. 20 (June 7, 2020): 3386–410. http://dx.doi.org/10.2174/0929867326666190227232721.

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Macrocycles cover a small segment of molecules with a vast range of biological activity in the chemotherapeutic world. Primarily, the natural sources derived from macrocyclic drug candidates with a wide range of biological activities are known. Further evolutions of the medicinal chemistry towards macrocycle-based chemotherapeutics involve the functionalization of the natural product by hemisynthesis. More recently, macrocycles based on carbohydrates have evolved a considerable interest among the medicinal chemists worldwide. Carbohydrates provide an ideal scaffold to generate chiral macrocycles with well-defined pharmacophores in a decorated fashion to achieve the desired biological activity. We have given an overview on carbohydrate-derived macrocycle involving their synthesis in drug design and discovery and potential role in medicinal chemistry.

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Zhong, Chunxiao, Yong Yan, Qian Peng, Zheng Zhang, Tao Wang, Xin Chen, Jiacheng Wang, Ying Wei, Tonglin Yang, and Linghai Xie. "Structure–Property Relationship of Macrocycles in Organic Photoelectric Devices: A Comprehensive Review." Nanomaterials 13, no. 11 (May 27, 2023): 1750. http://dx.doi.org/10.3390/nano13111750.

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Macrocycles have attracted significant attention from academia due to their various applications in organic field-effect transistors, organic light-emitting diodes, organic photovoltaics, and dye-sensitized solar cells. Despite the existence of reports on the application of macrocycles in organic optoelectronic devices, these reports are mainly limited to analyzing the structure–property relationship of a particular type of macrocyclic structure, and a systematic discussion on the structure–property is still lacking. Herein, we conducted a comprehensive analysis of a series of macrocycle structures to identify the key factors that affect the structure–property relationship between macrocycles and their optoelectronic device properties, including energy level structure, structural stability, film-forming property, skeleton rigidity, inherent pore structure, spatial hindrance, exclusion of perturbing end-effects, macrocycle size-dependent effects, and fullerene-like charge transport characteristics. These macrocycles exhibit thin-film and single-crystal hole mobility up to 10 and 26.8 cm2 V−1 s−1, respectively, as well as a unique macrocyclization-induced emission enhancement property. A clear understanding of the structure–property relationship between macrocycles and optoelectronic device performance, as well as the creation of novel macrocycle structures such as organic nanogridarenes, may pave the way for high-performance organic optoelectronic devices.

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Fan, Linmeng, Min Du, Lichun Kong, Yan Cai, and Xiaobo Hu. "Recognition Site Modifiable Macrocycle: Synthesis, Functional Group Variation and Structural Inspection." Molecules 28, no. 3 (January 31, 2023): 1338. http://dx.doi.org/10.3390/molecules28031338.

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Traditional macrocyclic molecules encode recognition sites in their structural backbones, which limits the variation of the recognition sites and thus, would restrict the adjustment of recognition properties. Here, we report a new oligoamide-based macrocycle capable of varying the recognition functional groups by post-synthesis modification on its structural backbone. Through six steps of common reactions, the parent macrocycle (9) can be produced in gram scale with an overall yield of 31%. The post-synthesis modification of 9 to vary the recognition sites are demonstrated by producing four different macrocycles (10–13) with distinct functional groups, 2-methoxyethoxyl (10), hydroxyl (11), carboxyl (12) and amide (13), respectively. The 1H NMR study suggests that the structure of these macrocycles is consistent with our design, i.e., forming hydrogen bonding network at both rims of the macrocyclic backbone. The 1H-1H NOESY NMR study indicates the recognition functional groups are located inside the cavity of macrocycles. At last, a preliminary molecular recognition study shows 10 can recognize n-octyl-β-D-glucopyranoside (14) in chloroform.

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Guo, Hao, Yu-Fei Ao, De-Xian Wang, and Qi-Qiang Wang. "Bioinspired tetraamino-bisthiourea chiral macrocycles in catalyzing decarboxylative Mannich reactions." Beilstein Journal of Organic Chemistry 18 (May 2, 2022): 486–96. http://dx.doi.org/10.3762/bjoc.18.51.

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A series of tetraamino-bisthiourea chiral macrocycles containing two diarylthiourea and two chiral diamine units were synthesized by a fragment-coupling approach in high yields. Different chiral diamine units, including cyclohexanediamines and diphenylethanediamines were readily incorporated by both homo and hetero [1 + 1] macrocyclic condensation of bisamine and bisisothiocyanate fragments. With the easy synthesis, gram-scale of macrocycle products can be readily obtained. These chiral macrocycles were applied in catalyzing bioinspired decarboxylative Mannich reactions. Only 5 mol % of the optimal macrocycle catalyst efficiently catalyzed the decarboxylative addition of a broad scope of malonic acid half thioesters to isatin-derived ketimines with excellent yields and good enantioselectivity. The rigid macrocyclic framework and the cooperation between the thiourea and tertiary amine sites were found to be crucial for achieving efficient activation and stereocontrol. As shown in control experiments, catalysis with the acyclic analogues having the same structural motifs were non-selective.

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6

Sun, Dianqing. "Recent Advances in Macrocyclic Drugs and Microwave-Assisted and/or Solid-Supported Synthesis of Macrocycles." Molecules 27, no. 3 (February 2, 2022): 1012. http://dx.doi.org/10.3390/molecules27031012.

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Macrocycles represent attractive candidates in organic synthesis and drug discovery. Since 2014, nineteen macrocyclic drugs, including three radiopharmaceuticals, have been approved by FDA for the treatment of bacterial and viral infections, cancer, obesity, immunosuppression, etc. As such, new synthetic methodologies and high throughput chemistry (e.g., microwave-assisted and/or solid-phase synthesis) to access various macrocycle entities have attracted great interest in this chemical space. This article serves as an update on our previous review related to macrocyclic drugs and new synthetic strategies toward macrocycles (Molecules, 2013, 18, 6230). In this work, I first reviewed recent FDA-approved macrocyclic drugs since 2014, followed by new advances in macrocycle synthesis using high throughput chemistry, including microwave-assisted and/or solid-supported macrocyclization strategies. Examples and highlights of macrocyclization include macrolactonization and macrolactamization, transition-metal catalyzed olefin ring-closure metathesis, intramolecular C–C and C–heteroatom cross-coupling, copper- or ruthenium-catalyzed azide–alkyne cycloaddition, intramolecular SNAr or SN2 nucleophilic substitution, condensation reaction, and multi-component reaction-mediated macrocyclization, and covering the literature since 2010.

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Kim, Taegwan, Eunbee Baek, and Jonghoon Kim. "Exploring Macrocyclic Chemical Space: Strategies and Technologies for Drug Discovery." Pharmaceuticals 18, no. 5 (April 24, 2025): 617. https://doi.org/10.3390/ph18050617.

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Macrocycles have emerged as significant therapeutic candidates in drug discovery due to their unique capacity to target complex and traditionally inaccessible biological interfaces. Their structurally constrained three-dimensional configurations facilitate high-affinity interactions with challenging targets, notably protein–protein interfaces. However, despite their potential, the synthesis and optimization of macrocyclic compounds present considerable challenges related to structural complexity, synthetic accessibility, and the attainment of favorable drug-like properties, particularly cell permeability and oral bioavailability. Recent advancements in synthetic methodologies have expanded the chemical space accessible to macrocycles, enabling the creation of structurally diverse and pharmacologically active compounds. Concurrent developments in computational strategies have further enhanced macrocycle design, providing valuable insights into structural optimization and predicting molecular properties essential for therapeutic efficacy. Additionally, a deeper understanding of macrocycles’ conformational adaptability, especially their ability to internally shield polar functionalities to improve membrane permeability, has significantly informed their rational design. This review discusses recent innovations in synthetic and computational methodologies that have advanced macrocycle drug discovery over the past five years. It emphasizes the importance of integrating these strategies to overcome existing challenges, illustrating how their synergy expands the therapeutic potential and chemical diversity of macrocycles. Selected case studies underscore the practical impact of these integrated approaches, highlighting promising therapeutic applications across diverse biomedical targets.

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Li, Yu, Wei Zhao, and Biao Wu. "Tetraurea Macrocycles: Template-Directed One-Pot Synthesis and Anion Binding Properties." Advances in Engineering Technology Research 6, no. 1 (June 19, 2023): 228. http://dx.doi.org/10.56028/aetr.6.1.228.2023.

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Given the significance of anion in life, study of anion recognition attracted great attentions in the past decades. Macrocyclic receptors display intriguing anion binding properties; however, the synthesis of macrocycles is challenging. Here, we reported a new strategy of making tetraurea in one-step. By using 1-butyl-3-methylimidazolium ([hmim][X], X = anion) as the solvent and template reagent, tetraurea macrocycle comprised of bis(urea) binding moiety and hexyl chain spacers is selectively formed with high yield. The obtained macrocycles displayed interesting anion binding properties as indicated by single crystal X-ray diffraction structures and computational modelling.

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9

Chia, PSK, A. Ekstrom, I. Liepa, LF Lindoy, M. Mcpartlin, SV Smith, and PA Tasker. "New Macrocyclic Ligands. II. Pendant Hydroxyethyl, Cyanoethyl and Carbamoylethyl Arm Systems Derived From O2N2-Donor Rings: the X-Ray Structure of a Pendant Hydroxyethyl Derivative." Australian Journal of Chemistry 44, no. 5 (1991): 737. http://dx.doi.org/10.1071/ch9910737.

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The syntheses and characterization of 12 new 14- to 17-membered macrocycles incorporating pendant hydroxyethyl cyanoethyl or carbamoylethyl groups are reported. The macrocyclic ring in each of these new ligands contains an O2N2-donor set. The X-ray structure of the di(hydroxyethyl) derivative of the 14-membered macrocycle is described.

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10

Mohammed, Shaymaa Adil. "Synthesis and Characterization of Some New Polymeric Macrocycle (Thia-Crown Ether) and Study Biological Activity." International Journal of Medical and All Body Health Research 6, no. 2 (2025): 87–98. https://doi.org/10.54660/ijmbhr.2025.6.2.87-98.

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This study investigates the synthesis, characterization, and biological activity of novel polymeric thia-crown ethers. On of the best solutions to save time and costs by mobilizing the chiral macrocycles on polymers which allows the recyclability and green conditions, The selecting of glucose as a model for the synthesis of macrocyclic thia crown ether The synthesis of thia-crown ether is started with protection of 4,6-positions on methyl D-glucopyranoside 1 by benzylidene protecting group, the reaction of compound 2 with bis(2-chloroethyl)ether under basic conditions to get compound 3 to obtain the structure which is ready to build up the macrocycle, the chloride can be enhanced by replacing it by iodide applying Flenksteien reaction to get compound 4. The macrocycle5 was treated in different reagent to get two derivatives in which 6 has only one free hydroxyl group, and 7 with two functional groups The compound 6 was crafted the PVC in order to obtain the target linear polymer 8. In the same context, the cross-linked polymer 9. All the compounds and polymers have been characterized by the instrumental techniques, include FT-IR, 1HNMR, 13CNMR and FESEM. The macrocycles 6, 7 and its polymeric materials was examined against two strains of bacteria, Gram + and Gram.

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11

Boyd, Simon, Nuno M. Cabral, Kenneth P. Ghiggino, Martin J. Grannas, W. David McFadyen, and Peter A. Tregloan. "Nickel complexation and photophysics of alkylanthracenyl dioxocyclam macrocycle derivatives." Australian Journal of Chemistry 53, no. 8 (2000): 651. http://dx.doi.org/10.1071/ch00106.

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Ligands H2L in which (10-R-anthracen-9-yl)methyl moieties (R = H, Me, Et) are covalently joined (6-position) to the 5,7-dioxocyclam macrocycle framework have been prepared and their nickel(II) complexes isolated and characterized. X-Ray crystal structures of NiIIL (R = H, Me) complexes show that in both structures the anthracene moieties are folded around towards the mean plane of the macrocycles; dihedral angles between the mean anthracene and macrocyclic planes of c. 22˚ are subtended. 1H n.m.r. spectrometry indicates that the folded conformations are retained in solution. Absorption and fluorescence spectra, fluorescence quantum yields and lifetimes of the anthracenyl macrocycles are reported. Absorption spectra of the metal complexes are red-shifted and the fluorescence is dramatically quenched compared to the metal-free compounds indicating a strong electronic interaction between the anthracene and the complexed dioxocyclam macrocycle.

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Hosseinzadeh, Parisa, Gaurav Bhardwaj, Vikram Khipple Mulligan, Matthew D. Shortridge, Timothy W. Craven, Fátima Pardo-Avila, Stephen A. Rettie, et al. "Comprehensive computational design of ordered peptide macrocycles." Science 358, no. 6369 (December 14, 2017): 1461–66. http://dx.doi.org/10.1126/science.aap7577.

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Mixed-chirality peptide macrocycles such as cyclosporine are among the most potent therapeutics identified to date, but there is currently no way to systematically search the structural space spanned by such compounds. Natural proteins do not provide a useful guide: Peptide macrocycles lack regular secondary structures and hydrophobic cores, and can contain local structures not accessible with l-amino acids. Here, we enumerate the stable structures that can be adopted by macrocyclic peptides composed of l- and d-amino acids by near-exhaustive backbone sampling followed by sequence design and energy landscape calculations. We identify more than 200 designs predicted to fold into single stable structures, many times more than the number of currently available unbound peptide macrocycle structures. Nuclear magnetic resonance structures of 9 of 12 designed 7- to 10-residue macrocycles, and three 11- to 14-residue bicyclic designs, are close to the computational models. Our results provide a nearly complete coverage of the rich space of structures possible for short peptide macrocycles and vastly increase the available starting scaffolds for both rational drug design and library selection methods.

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Fainerman-Melnikova, Marina, Leonard F. Lindoy, Show-Yee Liou, John C. McMurtrie, Noel P. Green, Azizollah Nezhadali, Gholamhossin Rounaghi, and William N. Setzer. "Metal-Ion Recognition—Selective Bulk Membrane Transport of Silver(I) Using Thioether Donor Macrocycles as Ionophores, and X-Ray Structure of the Silver Complex of an S4-Donor Ring." Australian Journal of Chemistry 57, no. 2 (2004): 161. http://dx.doi.org/10.1071/ch03239.

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Competitive metal-ion transport experiments, each involving transport from an aqueous source phase containing equimolar concentrations of cobalt(II), nickel(II), copper(II), zinc(II), cadmium(II), silver(i), and lead(II) across a chloroform membrane phase to an aqueous receiving phase have been carried out. The membrane phase incorporated an ionophore chosen from a series of thioether-containing macrocycles. For those systems that displayed transport behaviour, sole selectivity for silver(I) was observed under the conditions employed. The effect of variation in the macrocyclic sulfur atom donor set and the presence of hydrophilic ring substituents on transport efficiency is presented. An X-ray structure of the 1 : 1 silver(I) nitrate complex of a 16-membered, S4-donor macrocycle shows the presence of four crystallographically independent macrocycles displaying conformational isomerism. Each silver(I) has an approximate tetrahedral geometry, being bound to three sulfur atoms from three different macrocycles and to one nitrato ligand to yield a three-dimensional network.

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Roberge, Jacques Y., Pierre Giguere, Pierre Soucy, Yves L. Dory, and Pierre Deslongchamps. "First transannular Diels–Alder reactions involving tetrasubstituted non-activated dienophiles." Canadian Journal of Chemistry 72, no. 8 (August 1, 1994): 1820–29. http://dx.doi.org/10.1139/v94-231.

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Transannular Diels–Alder reactions of four 14-membered macrocyclic trienes (27, 28, 43, and 44) possessing a dimethyl tetrasubstituted dienophile have been investigated. Macrocycles having a cis-trans-cis (CTC) (27), a CTT (43), and a TTT (44) geometry produced the predicted trans-syn-cis (TSC) (45), cis-anti-cis (CAC) (48), and TAC (49) tricycles, respectively. The TTC macrocycle (28) gave exclusively the TST tricycle (46), no CSC tricycle (47) being observed. TTT macrocycle (44) underwent macrocyclization at a lower temperature than the TTC isomer (28).

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Nezhadali, A., and M. Akbarpour. "Selective Transport of Silver(I) Ion Through Polymer Membranes Containing Thioether Donor Macrocycles as Carriers." E-Journal of Chemistry 5, no. 2 (2008): 271–74. http://dx.doi.org/10.1155/2008/295413.

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The Preparation of polymer membrane and it's selectivity to silver(I) ion from an aqueous solution containing seven metal cations, Co(II), Ni(II), Cu(II), Zn(II), Ag(I), Cd(II) and Pb(II), was studied. The source phase contained equimolar concentrations of the above mentioned cations with the source and receiving phases being buffered at pH 5.0 and 3.0 respectively. The effect of variation in the number of the macrocyclic sulfur atom donor set anssd the size of ring 9 and 16 member macrocycles on transport efficiency is presented. Silver(I) ion transport occurred (at 25°C) from the aqueous source phase across the polymer membrane (derived from cellulos triacetate) containing ligands 9-membered, S3-donor and16-membered S4-donor macrocycles as the ionophors in separate experiments into the aqueous receiving phase. Clear transport selectivity for silver(I) ion was observed using both thioether donor macrocycles. The efficiency of transport rate for silver(I) ion with using 9-membered S3-donor macrocycle as carrier was better than 16-membered S4-donor .

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Boden, Britta N., Amir Abdolmaleki, Cecily T. Z. Ma, and Mark J. MacLachlan. "New diformyldihydroxyaromatic precursors for luminescent Schiff base macrocycles: Synthesis, characterization, and condensation studies." Canadian Journal of Chemistry 86, no. 1 (January 1, 2008): 50–64. http://dx.doi.org/10.1139/v07-136.

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With the goal of preparing luminescent, fully conjugated Schiff base macrocycles, a series of precursors based on benzene, phenanthrene, and triphenylene with formylhydroxy functionalization have been prepared and characterized. The condensation of these compounds with substituted phenylenediamines to afford conjugated [2+2] or [3+3] Schiff base macrocycle has been investigated. Although the [3+3] Schiff base macrocycles could not be isolated, two new soluble and luminescent [2+2] Schiff base macrocycles with N2O2 binding pockets have been prepared and characterized.Key words: Schiff base, macrocycle, condensation, salicylaldehyde, conjugated.

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Mishra, Purti, Pooja Sethi, and Anjana Kumari. "Emerging applications and host- guest chemistry of synthetic macrocycles." Research Journal of Chemistry and Environment 26, no. 7 (June 25, 2022): 153–57. http://dx.doi.org/10.25303/2607rjce153167.

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Synthetic macrocycles offer variety of biologically significant properties e.g. antibacterial, antifungal, anti-fertility, anticancerous, anti-inflammatory, anti-diabetic, anti-malarial, antiviral and antioxidant. DNA binding and cleaving agents are thoroughly used in area of medicinal chemistry. Host-guest chemistry is the one of most fascinating parts of macrocycles. Literature suggests various macrocycles with the potential therapeutic properties. Magnetic resonance imagining (MRI) contrast agent, dopamine detection, photochemical properties as sensor and catalytic activities of macrocycle are most attracting and growing fields of naturally mimic synthetic macrocycles. In recent years, interest has aroused on Schiff based macrocycles and synthetic strategies were employed to develop novel macrocycles with engrossed properties and applications.

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Duckworth, PA, LF Lindoy, M. Mcpartlin, and PA Tasker. "New Macrocyclic Ligands. IV. Dibenzo-Substituted Rings Incorporating Five Donor Atoms. X-Ray Structures of an N4O-Donor Macrocycle, Its Protonated Form, and Its Complex With Barium Perchlorate." Australian Journal of Chemistry 46, no. 11 (1993): 1787. http://dx.doi.org/10.1071/ch9931787.

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The syntheses and characterization of four dibenzo-substituted macrocycles incorporating N5-, N4O-or N4S-donor sets are reported. The new systems extend the range of related (potentially pentadentate ) macrocyclic systems of this general structure reported previously. For the 17-membered macrocycle incorporating an N4O-donor set, X-ray structure determinations of the free ligand and its salt of type [LH]ClO4 confirm the structure of this compound predicted from physical measurements. The diperchloratobarium complex of this macrocycle is shown to have the barium nine-coordinate; the coordination sphere is composed of the N4O-donors of the macrocycle and four oxygen atoms derived from a monodentate as well as a bidentate perchlorate group and an ethanol molecule.

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Yampolska, H., S. Kharchenko, A. Kozytskyi, A. Kyrylchuk, Z. Voitenko, and O. Grygorenko. "SYNTHESIS OF A 1,2,3-TRIAZOLE-CONTAINING MACROCYCLE BASED ON THE "CLICK CHEMISTRY" REACTION AND ANALYSIS OF ITS PLANAR CHIRALITY USING NMR AND DFT CALCULATIONS." Bulletin of Taras Shevchenko National University of Kyiv. Chemistry, no. 1 (57) (2020): 55–61. http://dx.doi.org/10.17721/1728-2209.2020.1(57).14.

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Macrocycles represent previously unexplored promising drug candidates, that can be useful for treating protein-protein interactions. Atropoisomerism is an inherent feature of the natural macrocyclic peptides that is significant for their activity and selectivity, and, therefore, should be introduced into newly synthesized macrocycles. Synthesis of the libraries of artificial macrocycles faces many challenges due to their structure and size. Herein we report on the preparation of a 16-membered macrocycle containing 1,2,3-triazole ring, spiro-piperidine, and phenyl moieties, as well as a chiral carbon atom. Our approach to the macrocycle was inspired by the "build/couple/pair" (B/C/P) strategy, a part of diversity-oriented synthesis methodology. We have employed readily accessible starting materials and robust synthetic procedures which allowed us to obtain the target macrocycle in a high yield. Standard methods of amide bond formation were used for the coupling of macrocycle building blocks. Click chemistry azide-alkyne cycloaddition was exploited at the final ring closure step. The assignment of signals in 1H and 13C NMR spectra of the macrocycle was performed using a series of 2D NMR techniques. The macrocycle displayed planar chirality, which, in a combination with a stereocenter with the known configuration, was sufficient to propose possible structures of diastereomers. The diastereomers could differ by the relative position of triazole ring. Their racemization could occur through a "rope skipping" motion involving the cyclic chain crossing the plane of 1,2,3-triazole ring. The supposed structures of diastereomers were corroborated by means of a various NMR spectroscopy techniques and DFT calculations. Analysis of the amide NH chemical shift temperature coefficients coupled with the data on optimized geometries obtained by DFT convincingly demonstrated that the intramolecular hydrogen bonds play a major role in stabilization of the diastereomer structures. According to the variable temperature NMR experiment, the interconversion of two diastereomers did not occur even at heating up to 70 °C.

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Liang, Yan, Ru Fang, and Qiu Rao. "An Insight into the Medicinal Chemistry Perspective of Macrocyclic Derivatives with Antitumor Activity: A Systematic Review." Molecules 27, no. 9 (April 29, 2022): 2837. http://dx.doi.org/10.3390/molecules27092837.

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The profound pharmacological properties of macrocyclic compounds have led to their development as drugs. In conformationally pre-organized ring structures, the multiple functions and stereochemical complexity provided by the macrocycle result in high affinity and selectivity of protein targets while maintaining sufficient bioavailability to reach intracellular locations. Therefore, the construction of macrocycles is an ideal choice to solve the problem of “undruggable” targets. Inspection of 68 macrocyclic drugs on the market showed that 10 of them were used to treat cancer, but this structural class still has been poorly explored within drug discovery. This perspective considers the macrocyclic compounds used for anti-tumor with different targets, their advantages and disadvantages, and the various synthetic methods of them.

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Timur, Ashirov, Alrayyani Maymounah, Song Kyung-Seob, Š. Miljanić Ognjen, and Coskun Ali. "Cyclotetrabenzil-Based Porous Organic Polymers with High Carbon Dioxide Affinity." Organic Materials 3 (May 19, 2021): 346–52. https://doi.org/10.1055/a-1512-5753.

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Porous organic polymers (POPs) incorporating macrocyclic units have been investigated in recent years in an effort to transfer macrocycles’ intrinsic host–guest properties onto the porous networks to achieve complex separations. In this regard, highly interesting building blocks are presented by the family of cyclotetrabenzoin macrocycles with rigid, well-defined, electron-deficient cavities. This macrocycle shows high affinity towards linear guest molecules such as carbon dioxide, thus offering an ideal building block for the synthesis of CO2-philic POPs. Herein, we report the synthesis of a POP through the condensation reaction between cyclotetrabenzil and 1,2,4,5-tetraaminobenzene under ionothermal conditions using the eutectic zinc chloride/sodium chloride/potassium chloride salt mixture at 250 °C. Notably, following the condensation reaction, the macrocycle favors three-dimensional (3D) growth rather than a two-dimensional one while retaining the cavity. The resulting polymer, named 3D-mPOP, showed a highly microporous structure with a BET surface area of 1142 m2 g1 and a high carbon dioxide affinity with a binding enthalpy of 39 kJ mol1 . Moreover, 3D-mPOP showed very high selectivity for carbon dioxide in carbon dioxide/methane and carbon dioxide/nitrogen mixtures.

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Thallaj, Prof Dr Nasser. "Advancements in Pharmaceutical Science: Synthesis and Application of Molecular Cages Integrating N-Heterocyclic Carbenes for Enhanced Stability and Functionality." International Journal of Advanced Pharmaceutical Sciences and Research 5, no. 1 (December 30, 2024): 6–19. https://doi.org/10.54105/ijapsr.a4063.05011224.

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The synthesis of molecular cages to encapsulate chemical entities, such as metal ions, anions, or small molecules, has emerged as a significant area of research in supramolecular chemistry. This article explores the design and construction of various macrocyclic ligands, particularly crown ethers, cryptands, and multi-branched macrocycles, highlighting their unique structural properties and coordination chemistry with transition metals and alkali ions. We delve into the role of N-Heterocyclic Carbenes (NHCs) in enhancing the stability and functionality of these macrocyclic systems. The integration of NHCs into macrocyclic architectures presents opportunities for novel applications in catalysis, photoluminescence, and biomedical fields. By examining the advancements in macrocycle-NHC chemistry, this article underscores the potential of these systems in developing innovative materials with tailored properties for diverse applications.

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Zuo, Minzan, Krishnasamy Velmurugan, Kaiya Wang, Xueqi Tian, and Xiao-Yu Hu. "Insight into functionalized-macrocycles-guided supramolecular photocatalysis." Beilstein Journal of Organic Chemistry 17 (January 18, 2021): 139–55. http://dx.doi.org/10.3762/bjoc.17.15.

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Due to the unique characteristics of macrocycles (e.g., the ease of modification, hydrophobic cavities, and specific guest recognition), they can provide a suitable environment to realize photocatalysis via noncovalent interactions with different substrates. In this minireview, we emphasized the photochemical transformation and catalytic reactivity of different guests based on the binding with various macrocyclic hosts as well as on the role of macrocyclic-hosts-assisted hybrid materials in energy transfer. To keep the clarity of this review, the macrocycles are categorized into the most commonly used supramolecular hosts, including crown ethers, cyclodextrins, cucurbiturils, calixarenes, and pillararenes. This minireview not only summarizes the role that macrocycles play in photocatalytic reactions but also clarifies the photocatalytic mechanisms. Finally, the future research efforts and new pathways to apply macrocycles and supramolecular hybrid materials in photocatalysis are also discussed.

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Merner, Bradley, Nirmal Mitra, and Caroline Merryman. "Highly Strained para-Phenylene-Bridged Macrocycles from Unstrained 1,4-Diketo Macrocycles." Synlett 28, no. 17 (August 22, 2017): 2205–11. http://dx.doi.org/10.1055/s-0036-1589081.

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The conversion of macrocyclic 1,4-diketones to highly strained para-phenylene rings has recently been reported by our laboratory. This synthetic strategy represents a non-cross-coupling-based approach to arene-bridged macrocycles, and an alternative to palladium- and nickel-mediated processes. In this Synpacts article we discuss the development of endgame aromatization protocols for the synthesis of increasingly strained arene systems, as well as potential advantages of the macrocyclic 1,4-diketone approach to selectively functionalized benzenoid macrocycles for future complexity building reactions.1 Introduction2 A Non-Cross-Coupling-Based Approach to Arene-Bridged Macro cycles3 Macrocyclic 1,4-Diketones: Streamlined Synthesis and Size-Dependent Diastereoselective Grignard Reactions4 Dehydrative Aromatization Reactions: A Powerful Tool for Synthesizing Highly Strained para-Phenylene Units5 Conclusion

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25

Kallert, Uwe, and Rainer Mattes. "Komplexe 17-gliedriger Dibenzo-Makrocyclen mit N3O2- bzw. N3S2-Donorzentren Strukturen von [Zn(′N3O2′)Cl]2ZnCl4 und [Hg(′N3S2′)Br2] / Complexes of 17-Membered Dibenzo Macrocycles with N3O2 or N3S2 Donor Sets Crystal and Molecular Structures of [Zn(′N3O2′)Cl]2ZnCl4 and [Hg(′N3S2′)Br2]." Zeitschrift für Naturforschung B 47, no. 9 (September 1, 1992): 1271–75. http://dx.doi.org/10.1515/znb-1992-0910.

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Abstract (sommario):

The macrocyclic complexes [Zn(′N3O2')Cl]2ZnCl4 (1) und [Hg(′N3S2')Br2] (2) have been prepared and their crystal structures determined. Zn(II) is incorporated into the macrocyclic cavity of the ′N3O2′ ligand and primarly coordinated to the three nitrogen donors of the macrocycle and to a chloride ion. Weaker interactions occur with the oxygen donors of the macrocycle. The Zn—O distances are 296,4(5) and 322,4(6) pm. In complex 2 Hg(II) lies outside the macrocyclic cavity. The donor set comprises two secondary amine nitrogen atoms and a thioether sulfur atom of the macrocycle, and two bromide anions. The coordination polyhedron can be described as a trigonal bipyramid. The conformational behaviour of the ′N3O2′ and the ′N3S2′ ligands within these and other complexes is discussed. ′N3O2′ and ′N3S2′ are 17-membered dibenzo macrocycles. Crystal data for [Zn(′N3O2')Cl]2ZnCl4 (1): monoclinic, space group C2/c, a = 2864(4), b = 951.0(2), c = 1986(4) pm, β = 118.5(1)°, Z = 4, 2499 reflections, R = 0.0581; [Hg(′N3S2′)Br2] (2): monoclinic, space group P21/c, a = 887.0(2), b = 1307.6(3), c = 2002.3(4) pm, β = 94.13(3)°, Z = 4,3123 reflections, R = 0.072.

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26

Prof., Dr. Nasser Thallaj. "Advancements in Pharmaceutical Science: Synthesis and Application of Molecular Cages Integrating N-Heterocyclic Carbenes for Enhanced Stability and Functionality." International Journal of Advanced Pharmaceutical Sciences and Research (IJAPSR) 5, no. 1 (December 30, 2024): 6–19. https://doi.org/10.54105/ijapsr.A4063.05011224.

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Abstract (sommario):

Abstract: The synthesis of molecular cages to encapsulate chemical entities, such as metal ions, anions, or small molecules, has emerged as a significant area of research in supramolecular chemistry. This article explores the design and construction of various macrocyclic ligands, particularly crown ethers, cryptands, and multi-branched macrocycles, highlighting their unique structural properties and coordination chemistry with transition metals and alkali ions. We delve into the role of N-Heterocyclic Carbenes (NHCs) in enhancing the stability and functionality of these macrocyclic systems. The integration of NHCs into macrocyclic architectures presents opportunities for novel applications in catalysis, photoluminescence, and biomedical fields. By examining the advancements in macrocycle-NHC chemistry, this article underscores the potential of these systems in developing innovative materials with tailored properties for diverse applications.

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27

Gagnon, Christina, Éric Godin, Clémentine Minozzi, Johann Sosoe, Corentin Pochet, and Shawn K. Collins. "Biocatalytic synthesis of planar chiral macrocycles." Science 367, no. 6480 (February 20, 2020): 917–21. http://dx.doi.org/10.1126/science.aaz7381.

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Abstract (sommario):

Macrocycles can restrict the rotation of substituents through steric repulsions, locking in conformations that provide or enhance the activities of pharmaceuticals, agrochemicals, aroma chemicals, and materials. In many cases, the arrangement of substituents in the macrocycle imparts an element of planar chirality. The difficulty in predicting when planar chirality will arise, as well as the limited number of synthetic methods to impart selectivity, have led to planar chirality being regarded as an irritant. We report a strategy for enantio- and atroposelective biocatalytic synthesis of planar chiral macrocycles. The macrocycles can be formed with high enantioselectivity from simple building blocks and are decorated with functionality that allows one to further modify the macrocycles with diverse structural features.

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28

Srungavruksham, Nagarjuna Kumar, and Viswanathan Baskar. "Te4Se2O6 macrocycle stabilizing triangular planar and tetrahedral anions." Dalton Transactions 44, no. 10 (2015): 4554–59. http://dx.doi.org/10.1039/c4dt03911d.

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Abstract (sommario):

The anion exchange reactions of Cl-macrocycle 1a with anions of varying geometry (NO3− trigonal planar, ClO4− and BF4− tetrahedral) have been investigated to yield macrocycles 2–4. Solid state molecular structures of these macrocycles are also retained in solution.

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29

Nasri, Fariborz. "A Review of the Thermodynamics of Complexation of Crown Ethers With Metal Ion." Journal of Advances in Environmental Health Research 10, no. 4 (October 1, 2022): 263–72. http://dx.doi.org/10.32598/jaehr.10.4.1218.

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Abstract (sommario):

Recently, macrocyclic and supramolecular chemistry has reached a hopeful area of research in the mutual interaction between chemistry, physics and biology. Charles J. Pedersen, at du Pont figure out a compound in the early 1960s famous for dibenzo-18-crown-6 (DB18C6) later on. The detection of the complex formation in solution, the designation of the stability of the consequence complex or complexes and the determination of the thermodynamic or the kinetic parameters of the complex formation can be attained by a manifold of physicochemical measurements. Conformational rigidity or flexibility of macrocycles has a considerable penetration on their selective behavior. The number, type, and arrangement of donor atoms in the macrocyclic rings play a main role in macrocycle selectivity. Based on chemistry terminology, this is known as “host-guest” chemistry where the ether plays the role as the host and the ionic species as the guest. In organic solutions, crown ethers take the role of phase-transfer catalysts and agents in order to enhance the solubility of inorganic salts. Macrocycles need to compete with solvent molecules for the cations during the process of complexation. Consequently, variation of the solvent makes a considerable change in the manifest binding characteristics of these ligands.

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30

Matsumoto, Toshihiko. "Simple One–Pot Synthesis of Hexakis(2-alkoxy-1,5-phenyleneimine) Macrocycles by Precipitation–Driven Cyclization." Macromol 4, no. 1 (January 3, 2024): 1–22. http://dx.doi.org/10.3390/macromol4010001.

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Abstract (sommario):

Hexakis(2-alkoxy-1,5-phenyleneimine) macrocycles were synthesized using a simple one-pot procedure through precipitation-driven cyclization. The acetal-protected AB–type monomers, 2-alkoxy-5-aminobenzaldehyde diethyl acetals, underwent polycondensation in water or acid-containing tetrahydrofuran. The precipitation–driven cyclization, based on imine dynamic covalent chemistry and π–stacked columnar aggregation, played a decisive role in the one–pot synthesis. The progress of the reaction was analyzed using MALDI–TOF mass spectrometry. The macrocycles with alkoxy chains were soluble in specific organic solvents, such as chloroform, allowing their structures to be analyzed using NMR. The shape-anisotropic, nearly planar, and shape-persistent macrocycles aggregated into columnar assemblies in polymerization solvents, driven by aromatic π-stacking. The octyloxylated macrocycle OcO–Cm6 exhibited an enantiotropic columnar liquid crystal-like mesophase between 165 °C and 197 °C. In the SEM image of (S)-(–)-3,7-dimethyloctyloxylated macrocycle (–)BCO–Cm6, columnar substances with a diameter of 200–300 nm were observed. The polymerization solution for the 2-(2-methoxyethoxy)ethoxy)ethoxylated macrocycle (TEGO–Cm6) gelled, and showed thixotropic properties by forming a hydrogen bond network.

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31

Liu, Na, Xing Wang, Hui Cao, Chun Hai Chen, and Wan Jin Zhang. "Synthesis of a Novel Hollow Sphere Having Rigid Binaphthyl Macrocycle as Shell." Solid State Phenomena 121-123 (March 2007): 219–22. http://dx.doi.org/10.4028/www.scientific.net/ssp.121-123.219.

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Abstract (sommario):

A novel hollow sphere having rigid binaphthyl macrocycle as shell was prepared by means of sacrifice the silica core. The synthesis of hollow sphere from rigid colloidal silica particles occurs in three steps: a) modification of silica particles with vinyltriethoxysilane as coupling agent, b) immersion in the solution of monomer having rigid binaphthyl macrocycle and polymerization, and c) removal of silica particles. These macrocycles contained in the shell of hollow spheres belong to an important class of host-guest macrocyclic material in which the rigid backbone and C2 symmetry of the binaphthyl unit play an important role in complexing guest molecules. This will endow hollow sphere with new opportunities in molecular recognition and separation.The morphology of colloidal silica particles and hollow spheres was characterized by SEM and TEM.

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32

Helweh, Waleed, Nathan C. Flanders, Shiwei Wang, Brian T. Phelan, Pyosang Kim, Michael J. Strauss, Rebecca L. Li, et al. "Layered structures of assembled imine-linked macrocycles and two-dimensional covalent organic frameworks give rise to prolonged exciton lifetimes." Journal of Materials Chemistry C 10, no. 8 (2022): 3015–26. http://dx.doi.org/10.1039/d1tc05840a.

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Abstract (sommario):

Excitonic dynamics studies of a 2D COF, its corresponding hexagonal macrocycle, and extended nanotubes comprised of stacked macrocycles reveal that layering of the macrocycle in the assembled COF and nanotube lead to a prolonged exciton lifetime.

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33

Dempsey, Janel M., Qi-Wei Zhang, Allen G. Oliver, and Bradley D. Smith. "New tetralactam hosts for squaraine dyes." Organic & Biomolecular Chemistry 16, no. 46 (2018): 8976–83. http://dx.doi.org/10.1039/c8ob02596g.

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34

Yu, Wentao, Zhiyao Yang, Chengkan Yu, Xiaowei Li, and Lihua Yuan. "Hydrogen-bonded macrocycle-mediated dimerization for orthogonal supramolecular polymerization." Beilstein Journal of Organic Chemistry 21 (January 17, 2025): 179–88. https://doi.org/10.3762/bjoc.21.10.

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Abstract (sommario):

Orthogonal self-assembly represents a useful methodology to construct supramolecular polymers with AA- and AB-type monomers, as commonly used for covalently linked polymers. So far, the design of such monomers has relied heavily on three-dimensional macrocycles, and the use of two-dimensional shape-persistent macrocycles for this purpose remains rather rare. Here, we demonstrate a dimerization motif based on a hydrogen-bonded macrocycle that can be effectively applied to form orthogonal supramolecular polymers. The macrocycle-mediated connectivity was confirmed by single-crystal X-ray diﬀraction, which revealed a unique 2:2 binding motif between host and guest, bridged by two cationic pyridinium end groups through π-stacking interactions and other cooperative intermolecular forces. Zinc ion-induced coordination with the macrocycle and a terpyridinium derivative enabled orthogonal polymerization, as revealed by 1H NMR, DLS, and TEM techniques. In addition, viscosity measurements showed a transition from oligomers to polymers at the critical polymerization concentration of 17 μM. These polymers were highly concentration-dependent. Establishing this new dimerization motif with shape-persistent H-bonded macrocycles widens the scope of noncovalent building blocks for supramolecular polymers and augurs well for the future development of functional materials.

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35

Li, Zheng, and Ying-Wei Yang. "Conjugated macrocycle polymers." Polymer Chemistry 12, no. 32 (2021): 4613–20. http://dx.doi.org/10.1039/d1py00759a.

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36

Sessler, Jonathan L., Won-Seob Cho, Stephen P. Dudek, Lindsay Hicks, Vincent M. Lynch, and Michael T. Huggins. "Synthesis and study of a calixpyrrole-texaphyrin chimera: A new oligopyrrolic chloride anion receptor." Journal of Porphyrins and Phthalocyanines 07, no. 02 (February 2003): 97–104. http://dx.doi.org/10.1142/s1088424603000136.

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Abstract (sommario):

Reported here is the synthesis and characterization of a new class of macrocycle that represents a hybrid between texaphyrin and calixpyrrole. These polypyrrolic macrocycles were prepared in one step by the acid-catalyzed condensation between diformyl dipyrromethanes and o-phenylenediamines in high yields. The X-ray crystal structure of one of these new “chimeras” was solved. It reveals that the diprotonated Schiff-base macrocycle has a V-shape in which one chloride anion is bound. Isothermal titration calorimetry (ITC) studies served to confirm the ability of the hybrid macrocycles to bind chloride anion in acetonitrile solution. These compounds may be useful as easy-to-make anion receptors.

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37

Salveson, Patrick J., Adam P. Moyer, Meerit Y. Said, Gizem Gӧkçe, Xinting Li, Alex Kang, Hannah Nguyen, et al. "Expansive discovery of chemically diverse structured macrocyclic oligoamides." Science 384, no. 6694 (April 26, 2024): 420–28. http://dx.doi.org/10.1126/science.adk1687.

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Abstract (sommario):

Small macrocycles with four or fewer amino acids are among the most potent natural products known, but there is currently no way to systematically generate such compounds. We describe a computational method for identifying ordered macrocycles composed of alpha, beta, gamma, and 17 other amino acid backbone chemistries, which we used to predict 14.9 million closed cycles composed of >42,000 monomer combinations. We chemically synthesized 18 macrocycles predicted to adopt single low-energy states and determined their x-ray or nuclear magnetic resonance structures; 15 of these were very close to the design models. We illustrate the therapeutic potential of these macrocycle designs by developing selective inhibitors of three protein targets of current interest. By opening up a vast space of readily synthesizable drug-like macrocycles, our results should considerably enhance structure-based drug design.

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38

Jie, Kecheng, Yujuan Zhou, Yong Yao, and Feihe Huang. "Macrocyclic amphiphiles." Chemical Society Reviews 44, no. 11 (2015): 3568–87. http://dx.doi.org/10.1039/c4cs00390j.

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Abstract (sommario):

This review describes recent results in the investigation of macrocyclic amphiphiles, which are classified based on different macrocyclic frameworks including cyclodextrins, calixarenes, cucurbiturils, pillararenes, and other macrocycles involved.

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39

Fairlie, David P., Giovanni Abbenante, and Darren R. March. "Macrocyclic Peptidomimetics Forcing Peptides into Bioactive Conformations." Current Medicinal Chemistry 2, no. 2 (August 1995): 654–86. http://dx.doi.org/10.2174/0929867302666220218001506.

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Abstract (sommario):

Abstract: Cyclic peptides that are potent regulators of biological processes are rapidly emerging as important mechanistic probes and drug leads. Nature clearly uses macrocycles to. constrain peptides into conformations that can selectively bind proteins or. small molecules. Therapeutic effects of such macrocycles, often containing additional conformational constraints that fine tune structure (e.g. D-amino acids, N-methyl substituents, aromatic rings, to name a few), have so far been mainly discovered by accident. However it is now becoming possible to rationally design synthetic macrocycles to selectively recognize and inhibit a specific protein. A receptor-binding struc ture is more easily adopted by macrocyclic peptidomimetics than more flexible acyclic peptides because the former have less conformational entropy. Macrocycles are often stable to hydrolysis by peptidases that degrade acyclic peptides and hydrophobic side chains can protect peptide bonds in macrocycles from hydrolysis, as well as enhance lipophilicity, cell permeability and bioavailability. Synthetic efforts to obtain bioactive conformations of short peptides have so far been substrate-based, guided by molecular modelling predictions and structure-activity data for modified amino acid sequences of substrates. However, dramatic advances in molecular biology, X-ray crystallography, NMR spectroscopy and computing are rapidly producing three dimensional structures of proteins, promising direct observation of protein-bound conformations of small molecules and receptor-based design of peptidomimetics with surface complementarity for proteins. This perspective review highlights examples of both natural and synthetic bioactive macrocyclic peptides containing constraints that fix conformation, and briefly illustrates the promise that receptor-based design holds for structural and functional mimicry of peptides by macrocycles.

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40

Olsson, Sandra, Óscar Benito Pérez, Magnus Blom, and Adolf Gogoll. "Effect of ring rize on photoisomerization properties of stiff stilbene macrocycles." Beilstein Journal of Organic Chemistry 15 (October 11, 2019): 2408–18. http://dx.doi.org/10.3762/bjoc.15.233.

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Abstract (sommario):

A series of stiff stilbene macrocycles have been studied to investigate the possible impact of the macrocycle ring size on their photodynamic properties. The results show that reducing the ring size counteracts the photoisomerization ability of the macrocycles. However, even the smallest macrocycle studied (stiff stilbene subunits linked by a six carbon chain) showed some degree of isomerization when irradiated. DFT calculations of the energy differences between the E- and Z-isomers show the same trend as the experimental results. Interestingly the DFT study highlights that the energy difference between the E- and Z-isomers of even the largest macrocycle (linked by a twelve carbon chain) is significantly higher than that of the stiff stilbene unit itself. In general, it is indicated that addition of even a flexible chain to the stiff stilbene unit may significantly affect its photochemical properties and increase the photostability of the resulting macrocycle.

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41

Anders, Patrick, Mario Rapp, Michael Linseis, and Rainer Winter. "Tetraruthenium Metallamacrocycles with Potentially Coordinating Appended Functionalities." Inorganics 6, no. 3 (July 24, 2018): 73. http://dx.doi.org/10.3390/inorganics6030073.

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Abstract (sommario):

We present four new tetraruthenium macrocycles built from two 1,4-divinylphenylene diruthenium and two isophthalic acid building blocks with peripheral, potentially mono- or tridentate donor functions attached to the isophthalic linkers. These macrocycles are characterized by multinuclear NMR spectroscopy, mass spectrometry and, in the case of the thioacetyl-appended complex 4, by X-ray crystallography. Cyclic and square wave voltammetry establish that the macrocycles can be oxidized in four consecutive redox steps that come as two pairs of two closely spaced one-electron waves. Spectroscopic changes observed during IR and UV/Vis/NIR spectroelectrochemical experiments (NIR = near infrared) show that the isophthalate linkers insulate the electroactive divinylphenylene diruthenium moieties against each other. The macrocycles exhibit nevertheless pronounced polyelectrochromism with highly intense absorptions in the Vis (2+/4+ states) and the NIR (2+ states) with extinction coefficients of up to >100,000 M−1·cm−1. The strong absorptivity enhancement with respect to the individual divinylphenylene diruthenium building blocks is attributed to conformational restrictions imposed by the macrocycle backbone. Moreover, the di- and tetracations of these macrocycles are paramagnetic as revealed by EPR spectroscopy.

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42

Xu, Rong-Yao, Xiu Liu, Guang Sun, Zhi-Yuan Zhang, Ming Dong, Liya Zhao, Si-Miao Zhang, et al. "Efficient macrocyclization facilitated by skeleton preorganization." RSC Advances 13, no. 43 (2023): 30269–72. http://dx.doi.org/10.1039/d3ra05671f.

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43

Desmond, Richard T., Anniefer N. Magpusao, Chris Lorenc, Jeremy B. Alverson, Nigel Priestley, and Mark W. Peczuh. "De novo macrolide–glycolipid macrolactone hybrids: Synthesis, structure and antibiotic activity of carbohydrate-fused macrocycles." Beilstein Journal of Organic Chemistry 10 (September 17, 2014): 2215–21. http://dx.doi.org/10.3762/bjoc.10.229.

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Abstract (sommario):

Natural product-like macrocycles were designed as potential antibacterial compounds. The macrocycles featured a D-glucose unit fused into a 12- or 13-member macrolactone. The rings are connected via the C6’ and anomeric (C1’) positions of the monosaccharide. The new macrocycles/macrolides were characterized by X-ray crystallography. Their structures showed that, in addition to the ester and alkene units, the dihedral angle about the glycosidic linkage (exo-anomeric effect) influenced the overall shape of the molecules. Glycosylation of an available hydroxy group on the macrocycle gave a hybrid macrolide with features common to erythromycin and sophorlipid macrolactone. Weak antibiotic activity (MICs <100 μg/mL) was observed for several of the compounds.

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44

Jiang, Zhiwei, Ruijiao Dong, Austin M. Evans, Niklas Biere, Mahmood A. Ebrahim, Siyao Li, Dario Anselmetti, William R. Dichtel, and Andrew G. Livingston. "Aligned macrocycle pores in ultrathin films for accurate molecular sieving." Nature 609, no. 7925 (August 31, 2022): 58–64. http://dx.doi.org/10.1038/s41586-022-05032-1.

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Abstract (sommario):

AbstractPolymer membranes are widely used in separation processes including desalination1, organic solvent nanofiltration2,3 and crude oil fractionation4,5. Nevertheless, direct evidence of subnanometre pores and a feasible method of manipulating their size is still challenging because of the molecular fluctuations of poorly defined voids in polymers6. Macrocycles with intrinsic cavities could potentially tackle this challenge. However, unfunctionalized macrocycles with indistinguishable reactivities tend towards disordered packing in films hundreds of nanometres thick7–9, hindering cavity interconnection and formation of through-pores. Here, we synthesized selectively functionalized macrocycles with differentiated reactivities that preferentially aligned to create well-defined pores across an ultrathin nanofilm. The ordered structure was enhanced by reducing the nanofilm thickness down to several nanometres. This orientated architecture enabled direct visualization of subnanometre macrocycle pores in the nanofilm surfaces, with the size tailored to ångström precision by varying the macrocycle identity. Aligned macrocycle membranes provided twice the methanol permeance and higher selectivity compared to disordered counterparts. Used in high-value separations, exemplified here by enriching cannabidiol oil, they achieved one order of magnitude faster ethanol transport and threefold higher enrichment than commercial state-of-the-art membranes. This approach offers a feasible strategy for creating subnanometre channels in polymer membranes, and demonstrates their potential for accurate molecular separations.

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45

Spiske, Moritz, Christian Meyners, Michael Bauder, Maximilian Repity, Christian Brudy, Wisely Oki Sugiarto, Hanaa Achaq, Thomas M. Geiger, and Felix Hausch. "Conformationally Restricted Macrocycles as Improved FKBP51 Inhibitors Enabled by Systematic Linker Derivatization." Angewandte Chemie International Edition, January 3, 2025. https://doi.org/10.1002/anie.202418511.

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Abstract (sommario):

Macrocycles are increasingly considered as promising modalities to target challenging intracellular proteins. However, strategies for transitioning from active linear starting points to improved macrocycles are still underdeveloped. Here we explored the derivatization of linkers as an approach for macrocycle optimization. Using the FK506‐binding protein 51 (FKBP51) as a model system we prepared >140 macrocycles with systematically derivatized linkers. Two backbones were identified as promising frameworks for subsequent optimization. Surprisingly, co‐crystal structure analyses revealed that these chemical templates represent an ensemble of three‐dimensional (3D) conformations that can give rise to several distinct 3D‐scaffolds. This resulted in a set of macrocycles with consistently improved affinity, plasma stability, and aqueous solubility compared to the linear precursors or the non‐functionalized macrocycles. Our results highlight linkers as an opportunity for macrocyclic drug development, show how linker derivatization can improve the performance of macrocycles, and emphasizes the need to track macrocyclic scaffold evolution at a three‐dimensional level.

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46

Spiske, Moritz, Christian Meyners, Michael Bauder, Maximilian Repity, Christian Brudy, Wisely Oki Sugiarto, Hanaa Achaq, Thomas M. Geiger, and Felix Hausch. "Conformationally Restricted Macrocycles as Improved FKBP51 Inhibitors Enabled by Systematic Linker Derivatization." Angewandte Chemie, January 3, 2025. https://doi.org/10.1002/ange.202418511.

Testo completo

Abstract (sommario):

Macrocycles are increasingly considered as promising modalities to target challenging intracellular proteins. However, strategies for transitioning from active linear starting points to improved macrocycles are still underdeveloped. Here we explored the derivatization of linkers as an approach for macrocycle optimization. Using the FK506‐binding protein 51 (FKBP51) as a model system we prepared >140 macrocycles with systematically derivatized linkers. Two backbones were identified as promising frameworks for subsequent optimization. Surprisingly, co‐crystal structure analyses revealed that these chemical templates represent an ensemble of three‐dimensional (3D) conformations that can give rise to several distinct 3D‐scaffolds. This resulted in a set of macrocycles with consistently improved affinity, plasma stability, and aqueous solubility compared to the linear precursors or the non‐functionalized macrocycles. Our results highlight linkers as an opportunity for macrocyclic drug development, show how linker derivatization can improve the performance of macrocycles, and emphasizes the need to track macrocyclic scaffold evolution at a three‐dimensional level.

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47

Shi, Xiaoyan, Felix León, How Chee Ong, Rakesh Ganguly, Jesús Díaz, and Felipe García. "Size-control in the synthesis of oxo-bridged phosphazane macrocycles via a modular addition approach." Communications Chemistry 4, no. 1 (February 22, 2021). http://dx.doi.org/10.1038/s42004-021-00455-9.

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Abstract (sommario):

AbstractInorganic macrocycles remain largely underdeveloped compared with their organic counterparts due to the challenges involved in their synthesis. Among them, cyclodiphosphazane macrocycles have shown to be promising candidates for supramolecular chemistry applications due to their ability to encapsulate small molecules or ions within their cavities. However, further developments have been handicapped by the lack of synthetic routes to high-order cyclodiphosphazane macrocycles. Moreover, current approaches allow little control over the size of the macrocycles formed. Here we report the synthesis of high-order oxygen-bridged phosphazane macrocycles via a “3 + n cyclisation” (n = 1 and 3). Using this method, an all-PIII high-order hexameric cyclodiphosphazane macrocycle was isolated, displaying a larger macrocyclic cavity than comparable organic crown-ethers. Our approach demonstrates that increasing building block complexity enables precise control over macrocycle size, which will not only generate future developments in both the phosphazane and main group chemistry but also in the fields of supramolecular chemistry.

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48

Thurakkal, Liya, Pandurangan Nanjan, and Mintu Porel. "Design, synthesis and bioactive properties of a class of macrocycles with tunable functional groups and ring size." Scientific Reports 12, no. 1 (March 21, 2022). http://dx.doi.org/10.1038/s41598-022-08775-z.

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Abstract (sommario):

AbstractThe design and synthesis of a versatile class of macrocycles with tunable functional groups and ring size are unfolded. Herein, a synthetic strategy is reported to furnish a new class of macrocycles in multi-gram scale in a two-step reaction. The total time taken for synthesizing a macrocycle is 1.5 h. Dithiocarbamates, an important functional group in biomedical and material sciences, is strategically incorporated in the macrocyclic backbone without metal for the first time. It is noteworthy that when state-of-the-art macrocycle synthesis is in millimolar concentration, this work employs the reaction in molar concentration (0.2–0.4 M). As proof-of-principle, a library of macrocycles was synthesized, varying the functional groups and ring size. The physicochemical properties of macrocycles revealed their druggable nature and are affirmed by protein (serum albumin) interaction study theoretically and experimentally. Diverse functional groups and ring sizes of macrocycles brought about twenty-five-fold difference in binding constant with the model protein.

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49

Kamboj, Monika. "Chemistry of tellurium containing macrocycles." Physical Sciences Reviews, May 17, 2022. http://dx.doi.org/10.1515/psr-2021-0106.

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Abstract (sommario):

Abstract The chemistry of Tellurium containing macrocycles has received great attraction and developed rapidly. Recently inorganic chemists are fascinated by ligands containing macrocycles having tellurium as soft donor and N and O as hard donor atoms. The tellurium atom is more electropositive than carbon due to its large size that resulted in polarisation of Te–C bond. So, tellurium containing macrocycles are explored due to their high reactivity and toxicity. Well-designed macrocycles containing different metals is an interesting field of chemistry as macrocycle with mixed donor atoms can bind two different metal atoms with different nature within the same cavity and thereby ion selectivity increases. Chemistry of macrocycles with tellurium as soft donor atoms also gives rise to very interesting coordination behaviour as addition of Tellurium in macrocycle adds an additional probe (125Te NMR help to monitor their structures in solutions). The chemistry of hard and soft donors in macrocyclic framework makes interesting coordination chemistry and need to be explore. The discussion includes different types of tellurium macrocycles and their chemistry.

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Wang, Shuangshuang, Yanzhen Yin, Jian Gao, Xingtang Liang, and Haixin Shi. "The Effects of the Solvents on the Macrocyclic Structures: From Rigid Pillararene to Flexible Crown Ether." Journal of the Brazilian Chemical Society, 2021. http://dx.doi.org/10.21577/0103-5053.20210088.

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Abstract (sommario):

The differences in the macrocyclic structures lead to different flexibilities, and yet the effect of solvents on the conformations is not clear so far. In this work, the conformations of four representational macrocyclic molecules (pillar[5]arene, p-tert-butyl calix[6]arene, benzylic amide macrocycle and dibenzo-18-crown-6) in three solvents with distinct polarity have been studied by all-atom molecular dynamics simulations. The structural features of the macrocycles in the solvents indicate that the conformations are related to the polarity of the solvents and the formation of hydrogen bonds. For the pillar[5]arene, the benzylic amide macrocycle and the dibenzo-18-crown-6, that cannot form intramolecular hydrogen bonds, the polarity of solvents is the major contributing factor in the conformations. The formation of intramolecular hydrogen bonds, in contrast, determinates the conformations of the calix[6]arene. Furthermore, the slight fluctuations of the structures will result in tremendous change of the intramolecular hydrogen bonds of the macrocycles and the intermolecular hydrogen bonds between the macrocycles and the solvents. The current theoretical studies that serve as a basis for the macrocyclic chemistry are valuable for the efficient structural design of the macrocyclic molecules.

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