Abstract
In a previous study, we reported a 1:1 complex (hemoCD) of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphinatoiron(II) (Fe(II)TPPS) with per-O-methylated β-cyclodextrin (CD) dimer having a pyridine (Py) linker, which was able to bind O2 and CO reversibly in aqueous solution. Among the CD dimers synthesized by us, the CD dimer (Py3OCD) that was linked via ether bonds at 3,3′-positions formed the best inclusion complex with Fe(II)TPPS and was utilized as an artificial O2 carrier and an antidote for cyanide anion poisoning. For practical applications, considerable amounts of Py3OCD need to be synthesized. However, the experimental conditions for the synthesis of Py3OCD have not been optimized as yet and an unidentified byproduct is sometimes obtained in the dimerization step. In this study, we identified the byproduct as the per-O-methylated CD dimer linked at the 6,6′-positions of two CDs. It was found that the undesired 6,6′-dimer was formed when the reaction temperature in the dimerization reaction was over 80 °C. This finding led us to effectively synthesize a large amount of Py3OCD in good yield, which is helpful for the practical use of hemoCD as an artificial O2 carrier or an antidote for cyanide anion.
Similar content being viewed by others
References
Breslow, R.: Biomimetic chemistry and artificial enzymes: catalysis by design. Acc. Chem. Res. 28, 146–153 (1995)
Collman, J.P., Boulatov, R., Sunderland, C.J., Fu, L.: Functional analogues of cytochrome c oxidase, myoglobin, and hemoglobin. Chem. Rev. 104, 561–588 (2004)
Kano, K., Kitagishi, H., Dagallier, C., Kodera, M., Matsuo, T., Hayashi, T., Hisaeda, Y., Hirota, S.: Iron porphyrin–cyclodextrin supramolecular complex as a functional model of myoglobin in aqueous solution. Inorg. Chem. 45, 4448–4460 (2006)
Kitagishi, H., Shimoji, D., Ohta, T., Kamiya, R., Kudo, Y., Onoda, A., Hayashi, T., Weiss, J., Wytko, J., Kano, K.: A water-soluble supramolecular complex that mimics the heme/copper hetero-binuclear site of cytochrome c oxidase. Chem. Sci. 9, 1989–1995 (2018)
Karasugi, K., Kitagishi, H., Kano, K.: Modification of a dioxygen carrier, HemoCD, whth PEGylated dendrons for extension of circulation time in the bloodstream. Bioconjug. Chem. 23, 2365–2376 (2012)
Ueda, T., Kitagishi, H., Kano, K.: Intramolecular direct oxygen transfer from oxoferryl porphyrin to a sulfide bond. Inorg. Chem. 53, 543–551 (2014)
Kano, K., Kitagishi, H., Kodera, M., Hirota, S.: Dioxygen binding to a simple myoglobin model in aqueous solution. Angew. Chem. Int. Ed. 44, 435–438 (2005)
Kano, K., Chimoto, S., Tamaki, M., Itoh, Y., Kitagishi, H.: Supramolecular dioxygen receptors composed of an anionic water-soluble porphinatoiron(II) and cyclodextrin dimers. Dalton Trans. 41, 453–461 (2012)
Kano, K., Itoh, Y., Kitagishi, H., Hayashi, T., Hirota, S.: A supramolecular receptor of diatomic molecules (O2, CO, NO) in aqueous solution. J. Am. Chem. Soc. 130, 8006–8015 (2008)
Watanabe, K., Kitagishi, H., Kano, K.: Supramolecular iron porphyrin/cyclodextrin dimer complex that mimics the functions of hemoglobin and methemoglobin. Angew. Chem. Int. Ed. 52, 6894–6897 (2013)
Kitagishi, H., Mao, Q., Kitamura, N., Kita, T.: HemoCD as a totally synthetic artificial oxygen carrier: improvements in the synthesis and O2/CO discrimination. Artif. Organs 41, 372–380 (2017)
Kano, K., Kitagishi, H., Tamura, S., Yamada, A.: anion binding to a ferric porphyrin complexed with per-O-methylated β-cyclodextrin in aquerous solution. J. Am. Chem. Soc. 126, 15202–15210 (2004)
Kitagishi, H., Minegishi, S., Yumura, A., Negi, S., Taketani, S., Amagase, Y., Mizukawa, Y., Urushidani, T., Sugiura, Y., Kano, K.: Feedback response to selective depletion of endogenous carbon monoxide in the blood. J. Am. Chem. Soc. 138, 5417–5425 (2016)
Acknowledgements
This work was financially supported by MEXT/JSPS KAKENHI (Grant Nos. 15H02569, 16K13092, 17H02208), the MEXT-Supported Program for the Strategic Research Foundation at Private Universities (2015–2019), the Naito Foundation, Takeda Science Foundation, Suntory Foundation for Life Sciences, and JGC-S Scholarship Foundation.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Mao, Q., Kitagishi, H. Optimized synthesis of a per-O-methylated β-cyclodextrin dimer linked at the secondary face by a pyridine ligand. J Incl Phenom Macrocycl Chem 93, 67–76 (2019). https://doi.org/10.1007/s10847-018-0839-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10847-018-0839-4