Microfluidic Mixing of Polyamine with Acrolein Enables the Detection of the [4+4] Polymerization of Intermediary Unsaturated Imines: The Properties of a Cytotoxic 1,5-Diazacyclooctane Hydrogel

Abstract

The [4+4] polymerization of an unsaturated imine, generated from the condensation of a polyamine and excess acrolein, was investigated. The polyamine was added by micropipet to acrolein, immediately yielding a mixture of the immiscible polymeric material. Microfluidic mixing was used to gradually form the soluble diazacyclooctane polymers. The polymerization reaction ultimately gave an insoluble cationic hydrogel that adhered strongly to anionic compounds on cell surfaces, including sialoglycan, and displayed a high cytotoxicity.

Key words

acrolein - N-alkyl unsaturated imine - cytotoxicity - 1,5-diazacyclooctane - hydrogel - microreactor - polyamine - [4+4] polymerization - sialoglycan

• Reference and Notes


For representative reviews, see:
• 1a Tanaka K, Fukase K, Katsumura S. Chem. Rec. 2010; 10: 119
• 1b Tanaka K, Fukase K, Katsumura S. Synlett 2011; 2115
• 2 For recent elegant examples in which the new reactivities of the N-alkyl unsaturated imines are explored, see: Shimizu M, Hachiya I, Mizota I. Chem. Commun. 2009; 874 ; and references cited therein
• 3 Tanaka K, Siwu ER. O, Hirosaki S, Iwata T, Matsumoto R, Kitagawa Y, Pradipta AR, Okamura M, Fukase K. Tetrahedron Lett. 2012; 53: 5899
• 4 Tsutsui A, Tanaka K. Org. Biomol. Chem. 2013; 11: 7208
• 5 Tanaka K, Matsumoto R, Pradipta AR, Kitagawa Y, Okumura M, Manabe Y, Fukase K. Synlett 2014; 25: 1026
• 6 Tsutsui A, Imamaki R, Kitazume S, Hanashima S, Yamaguchi Y, Kaneda M, Oishi S, Fujii N, Kurbangalieva A, Taniguchi N, Tanaka K. Org. Biomol. Chem. 2014; 12: 5151
• 7 Kehrer JP, Biswal SS. Toxicol. Sci. 2000; 57: 6
• 8a Alarcon RA. Arch. Biochem. Biophys. 1970; 137: 365
• 8b Kimes BW, Morris DR. Biochim. Biophys. Acta 1971; 228: 223
• 8c Houen G, Bock K, Jensen AL. Acta Chem. Scand. 1994; 48: 52
• 9a Sharmin S, Sakata K, Kashiwagi K, Ueda S, Iwasaki S, Shirahata A, Igarashi K. Biochem. Biophys. Res. Commun. 2001; 282: 228
• 9b Yoshida M, Tomitori H, Machi Y, Hagihara M, Higashi K, Goda H, Ohya T, Niitsu M, Kashiwagi K, Igarashi K. Biochem. Biophys. Res. Commun. 2009; 378: 313
• 10a Uchida K, Kanematsu M, Morimitsu Y, Osawa T, Noguchi N, Niki E. J. Biol. Chem. 1998; 273: 16058
• 10b Furuhata A, Ishii T, Kumazawa S, Yamada T, Nakayama T, Uchida K. J. Biol. Chem. 2003; 278: 48658
• 10c Uchida K, Kanematsu M, Sakai K, Matsuda T, Hattori N, Mizuno Y, Suzuki D, Miyata T, Noguchi N, Niki F, Osawa T. Proc. Natl. Acad. Sci. U.S.A. 1998; 95: 4882
• 10d Uchida K. Pharmacia 2012; 48: 26 ; and references cited therein
• 11 Jianhua L, Chun R, Zhu Y, Wenfang S. J. Polym. Sci., Part A: Polym. Chem. 2007; 45: 699

For pioneering reviews, see:
• 12a Microreaction Technology . Ehrfeld W. Springer; Berlin: 1998
• 12b Mycrosystem Technology in Chemistry and Life Sciences. Manz A, Becker H. Springer; Berlin: 1998
• 12c Ehrfeld W, Hessel V, Lowe H. Microreactors . Wiley-VCH; Weinheim: 2000
• 12d Hessel V, Hardt S, Lowe H. Chemical Micro Process Engineering . Wiley-VCH; Weinheim: 2004
• 12e Yoshida J.-I, Suga S, Nagaki A. J. Synth. Org. Chem. Jpn. 2005; 63: 511
• 13a Tanaka K, Fukase K. Org. Process Res. Dev. 2009; 13: 983
• 13b Tanaka K, Fukase K. Beilstein J. Org. Chem. 2009; 5: No. 40
• 14 Comet X-01 micromixer: http://homepage3.nifty.com/techno-applications/ or E-mail: [e-mail].
• 15 The [4+4] Polymerization of the Spermine/Polyamine-Derived Diimine under Microfluidic Conditions A solution of spermine (150 mg, 741 μmol) in PBS (2.0 mL) was injected, in advance, into the micromixer, a Comet X-01, using a syringe pump at a flow rate of 1.5 mL/min. A solution of acrolein (100 μL, 741 μmol) dissolved in PBS (2.0 mL) was then injected into the micromixer using another syringe pump at a same flow rate. The reaction was mixed at r.t. The reaction mixture was allowed to flow at r.t. for a few seconds through a Teflon tube reactor (Φ = 1.0 mm, l = 3.0 m) and was then introduced into a flask and left for 2 d at this temperature. A deuterated PBS buffer was used in the procedure described above to analyze the polymerization reaction over time using NMR methods. The PBS buffer was freeze-dried twice from D₂O prior to use.
• 16 When the reaction mixture was eluted from the microfluidic apparatus, a complex mixture of smaller polymerized diazacyclooctane fragments with molecular weights of 1,000–3,0000 were detected.
• 17 Cohen Y, Avram L, Frish L. Angew. Chem. Int. Ed. 2005; 44: 520
• 18 Tanaka K, Nakamoto Y, Siwu ER. O, Pradipta AR, Morimoto K, Fujiwara T, Yoshida S, Hosoya T, Tamura Y, Hirai G, Sodeoka M, Fukase K. Org. Biomol. Chem. 2013; 11: 7326
• 19 Interactions between the 1,5-Diazacyclooctane Hydrogel and Sialoglycan 2 The 1,5-diazaoctane hydrogel 1aa (2.0 mg) was treated with an aqueous solution of sialoglycan 2 (10^–5 M), and the mixture was allowed to incubate for 3.5 h at r.t. The gel was washed with H₂O (3×) and further soaked in H₂O for 1 h. The resulting gel was analyzed by OLYMPUS fluorescence microscopy, IX71-23FL/DIC.