Publications

～ Recent Publications ～
From 2000 to Present
  1. Kamiya, G.; Kitada, N.; Furuta, T.; Hirano, T.; Maki, S.A.; Kim, S.B. "S-Series Coelenterazine-Driven Combinatorial Bioluminescence Imaging Systems for Mammalian Cells" International Journal of Molecular Sciences 24, no. 2: 1420. (2023)
  2. Kamiya, G.; Kitada, N.; Furuta, T.; Hirano, T.; Maki, S.; Kim, S.B. "C-Series Coelenterazine-Driven Bioluminescence Signature Imaging" International Journal of Molecular Sciences 23, no. 21: 13047. (2022)
  3. Kamiya, G., Kitada, N., Maki, S. "Multiplex quadruple bioluminescent assay system" Sci Rep 12, 17485 (2022)
  4. Matsuhashi, C.; Fujisawa, H.; Ryu, M.; Tsujii, T.; Morikawa, J.; Maki, S.; Hirano, T. "Analyses of chemiluminescence reactions of fluorophore-linked 1,2-dioxetane isomers in crystals heating at elevated temperature including a development of a simultaneous measurement method of thermal diffusivity and light emission for a single crystal" Analytical Sciences, (2022), in press.
  5. Matsuhashi, C.; Oyama, H.; Uekusa, H.; Sato-Tomita, A.; Ichiyanagi, K.; Maki, S.; Hirano, T. "Crystalline-state chemiluminescence reactions of two-fluorophore-linked adamantylideneadamantane 1,2-dioxetane isomers accompanied by solid-to-solid phase transitions" CrystEngComm., 24, 3332 (2022). [※Front Coverに採択]
  6. Matsuhashi, C.; Fujisawa, H.; Ryu, M.; Tsujii, T.; Morikawa, J.; Oyama, H.; Uekusa, H.; Maki, S.; Hirano, T. "Intracrystalline kinetics analyzed by real-time monitoring of a 1,2-dioxetane chemiluminescence reaction in a single crystal" Bull. Chem. Soc. Jpn., 95, 413 (2022). [※Selected Paperに選出]
  7. Hirano, T.; Matsuhashi, C. "A stable chemiluminophore, adamantylideneadamantane 1,2-dioxetane: from fundamental properties to utilities in mechanochemistry and soft crystal science" J. Photochem. Photobiol. C, 51, 100483 (2022).
  8. Yamasaki, N.; Matsuhashi, C.; Maki, S.; Hirano, T. "Singlet-Oxygen Chemiluminescence from Heated Crystal Samples of 9, 10-Diphenylanthracene Endoperoxides" Chem. Lett. 50/9, 1681-1683 (2021).
  9. Saito-Moriya, R.; Nakayama, J.; Kamiya, G.; Kitada, N.; Obata, R.; Maki, S. A.; Aoyama, H. "How to Select Firefly Luciferin Analogues for In Vivo Imaging" Int. J. Mol. Sci., 22(4), 1848 (2021).
  10. Kamiya, G.; Kitada, N.; Saito-Moriya, R.; Obata, R.; Iwano, S.; Miyawaki, A.; Hirano, T.; Maki, S. "Development of phenyl oligoene-type firefly luciferin analogues with extended π-electronic conjugation for near-infrared bioluminescence" Chem. Lett. 50/8, 1523-1525 (2021).
  11. Yoshida, C.; Higashi, T.; Hachiro, T.; Fujita, Y.; Yagi, T; Takechi, A.; Nakata, C.; Miyashita, K.; Kitada, N.; Saito, R.; Obata, R.; Hirano, T.; Hara, T.; Maki, S. A. "Synthesis of polyenylpyrrole derivatives with selective growth inhibitory activity against T-cell acute lymphoblastic leukemia cells" Bioorg. Med. Chem. Lett. 37, 127837-4 pages (2021).
  12. Tamaki, S.; Kitada, N.; Kiyama, M.; Fujii, R.; Hirano, T.; Kim, S. B.; Maki, S. "Color-Tunable Bioluminescence Imaging Portfolio for Cell Imaging" Sci. Rep. 11, 2219-10 pages (2021).
  13. C. Matsuhashi, T. Ueno, H. Uekusa, A. Sato-Tomita, K. Ichiyanagi, S. Maki and T. Hirano,"Isomeric Difference in the Crystalline-state Chemiluminescence Property of an Adamantylideneadamantane 1,2-Dioxetane with a Phthahlimide Chromophore" Chemical Communications, 56(23), 3369-3372 (2020). [※Back Coverに採択]
  14. Nakayama, J.; Saito, R.; Hayashi, Y.; Kitada, N.; Tamaki, S.; Han, Y.;Semba, K.; Maki, S. A. "High Sensitivity In Vivo Imaging of Cancer Metastasis Using a Near-Infrared Luciferin Analogue seMpai" Int. J. Mol. Sci. 21 (21), 7896 (2020).
  15. Yuma Ikeda， Tsuyoshi Saitoh， Kazuki Niwa， Takahiro Nakajima， Nobuo Kitada， Shojiro A. Maki， Moritoshi Sato， Daniel Citterio， Shigeru Nishiyama， and Koji Suzuki; An Allylated Firefly Luciferin Analogue with Luciferase Specific Response in Living Cells， Chem. Commun.， 54，1774-1777 (2018).
  16. Fukuchi, M.; Saito, R.; Maki, S.; Hagiwara, N.; Nakajima, Y.; Mitazaki, S.; Izumi, H.; Mori, H.; "Visualization of activity-regulated BDNF expression in the living mouse brain using non-invasive near-infrared bioluminescence imaging" Mol. Brain 13 (1), 1-10 (2020).
  17. Kitada, N.; Saito, R.; Obata, R.; Iwano, S.; Karube, K.; Miyawaki, A.; Hirano, T.; Maki, S. A. “Development of near-infrared firefly luciferin analogue reacted with wild type and mutant luciferases” Chirality, 32, 922-931(2020) Article DOI: 10.1002/chir.23236.
  18. Saito, R.; Kuchimaru, T.; Higashi, S.; Lu, S. W.; Kiyama, M.; Iwano, S.; Obata, R.; Hirano, T.; Kizaka-Kondoh, S.; Maki, S. A. "Synthesis and Luminescence Properties of Near-Infrared N-Heterocyclic Luciferin Analogues for In Vivo Optical Imaging" Bull. Chem. Soc. Jpn. 92 (3),608-618 (2019).
  19. Y. Takahashi, T. Uehara, C. Matsuhashi, M. Yamaji, T. Mutai, I. Yoshikawa, H. Houjou, K. Kitagawa, T. Suenobu, S. A. Maki, T. Hirano, J. Spectroscopic properties of push-pull 2-(4-carboxyphenyl)-6-dimethylaminobenzothiazole derivatives in solution and the solid state Photochem. Photobiol. A., 2019, 376, 324-332.
  20. Kitada, N.; Saitoh, T.; Ikeda, Y.; Iwano, S.; Obata, R.; Niwa, H.; Hirano, T.; Miyawaki, A.; Suzuki, K.; Nishiyama, S.; et al. Toward Bioluminescence in the Near-Infrared Region: Tuning the Emission Wavelength of Firefly Luciferin Analogues by Allyl Substitution. Tetrahedron Lett. 2018, 59 (12), 1087–1090.
  21. Iwano, S.; Sugiyama, M.; Hama, H.; Watakabe, A.; Hasegawa, N.; Kuchimaru, T.; Tanaka, K. Z.; Takahashi, M.; Ishida, Y.; Hata, J.; et al. Single-Cell Bioluminescence Imaging of Deep Tissue in Freely Moving Animals. Science (80-. ). 2018, 359 (6378), 935–939.
  22. Kiyama, M.; Iwano, S.; Otsuka, S.; Lu, S. W.; Obata, R.; Miyawaki, A.; Hirano, T.; Maki, S. A. Quantum Yield Improvement of Red-Light-Emitting Firefly Luciferin Analogues for in Vivo Bioluminescence Imaging. Tetrahedron 2017, 74 (6), 652–660.
  23. Kakiuchi, M.; Ito, S.; Kiyama, M.; Goto, F.; Matsuhashi, T.; Yamaji, M.; Maki, S.; Hirano, T., “Electronic and steric effects of cyclic amino substituents of luciferin analogues on a firefly luciferin−luciferase reaction,” Chem. Lett. 46 (8), 1090–1092 (2017).
  24. Kakiuchi, M.; Ito, S.; Yamaji, M.; Viviani, V. R.; Maki, S.; Hirano, T., “Spectroscopic properties of amine-substituted analogues of firefly luciferin and oxyluciferin,” Photochem. Photobiol., 93, 486–494 (2017).
  25. Fukuchi, M.; Izumi, H.; Mori, H.; Kiyama, M.; Otsuka, S.; Maki, A.; Maehata, Y.; Tabuchi, A.; Tsuda, M., “Visualizing changes in brain-derived neurotrophic factor (BDNF) expression using bioluminescence imaging in living mice”, Sci. Rep., 7, 4949 (2017).
  26. Viviani, V. R.; Simoes, A. F.; Bevilaqua, V. R.; de Mello Gabriel, G. V.; Arnoldi, F. G. C.; Hirano, T., “Glu311 and Arg337 stabilize a closed conformation and provide a critical catalytic base and countercation for green bioluminescence in beetle luciferases,” Biochemistry, 55, 4764–4776 (2016).
  27. Hachiya, S.; Hashizume, D.; Ikeda, H.; Yamaji, M.; Maki, S.; Niwa, H.; Hirano, T., “Spectroscopic properties of BF2 complexes of N-(5-phenyl-2-pyrazinyl)pivalamides exhibiting fluorescence in solution and solid state,” J. Photochem. Photobiol. A, 331, 206–214 (2016).
  28. Suzuki, Y.; Yamaji, M.; Maki, S.; Hirano, T., “Enhanced brightness of 2,6-diphenylthiazolo[4,5-b]pyrazines by introducing double electron donating groups,” J. Photochem. Photobiol. A, 314, 93–95 (2016).
  29. Ioka, S.; Saitoh, T.; Iwano, S.; Suzuki, K.; Maki, S. A.; Miyawaki, A.; Imoto, M.; Nishiyama, S., “Synthesis of firefly luciferin analogues and evaluation of the luminescent properties”, Chem. Eur. J., 22, 9330–9337 (2016).
  30. Kuchimaru, T.; Iwano, S.; Kiyama, M.; Mitsumata, S.; Kadonosono, T.; Niwa, H.; Maki, S.; Kizaka-Kondoh, S., “A luciferin analog generating near-infrared bioluminescence achieves highly sensitive deep-tissue imaging”, Nature Commun., 7, 11856 (2016).
  31. Kiyama, M.; Saito, R.; Iwano, S.; Obata, R.; Niwa, H.; Maki, S., “Multicolor bioluminescence obtained using firefly luciferin”, Curr. Top. Med. Chem., 16, 2648-2655 (2016).
  32. Hirano, T., “Molecular origin of color variation in firefly (beetle) bioluminescence: a chemical basis for biological imaging,” Curr. Top. Med. Chem., 16, 2638–2647 (2016).
  33. Ioka, S.; Saitoh, T.; Iwano, S.; Suzuki, K.; Maki, S.; Niwa, H.; Miyawaki, A.; Imoto, M.; Nishiyama, S., “Synthesis and evaluation of the luminescent properties of firefly luciferin analogues” Chem. Eur. J., 22, 1-9 (2016).
  34. Nakagawa, T.; Yamaji, M.; Maki, S.; Niwa, H.; Hirano, T., “Fluorescence properties of diphenylthiazolo[4,5-b]pyrazines tuned by donor-acceptor substituent effects,” Photochem. Photobiol., 91, 807–813 (2015).
  35. Nakagawa, T.; Yamaji, M.; Maki, S.; Niwa, H.; Hirano, T., “Substituent effects on fluorescence properties of thiazolo[4,5-b]pyrazine derivatives,” Photochem. Photobiol. Sci., 13, 1765–1772 (2014).
  36. Viviani, V. R.; Rodrigues, D.; Amaral, D.; Prado, R. A.; Matsuhashi, T.; Hirano, T., “Bioluminescence of beetle luciferases with 6’-amino-D-luciferin analogues reveals excited keto-oxyluciferin as the emitter and phenolate/luciferin binding site interactions modulate bioluminescence colors,” Biochemistry, 53, 5208–5220 (2014).
  37. Saito, R.; Hirano, T.; Maki, S.; Niwa, H., “Synthesis and chemiluminescent properties of 6,8-diaryl-2-methylimidazo[1,2-a]pyrazin-3(7H)-ones: systematic investigation of substituent effect at para-position of phenyl group at 8-position,” J. Photochem. Photobiol. A, 293, 12–25 (2014).
  38. Ishii, Y.; Hayashi, C.; Suzuki, Y.; Hirano, T., “Chemiluminescent 2,6-diphenylimidazo[1,2-a]pyrazin-3(7H)-ones: a new entry to Cypridina luciferin analogues,” Photochem. Photobiol. Sci., 13, 182–189 (2014).
  39. Miura, C.; Kiyama, M.; Iwano, S.; Ito, K.; Obata, R.; Hirano, T.; Maki, S.; Niwa, H., “Synthesis and luminescence properties of biphenyl-type firefly luciferin analogs with a new, near-infrared light-emitting bioluminophore,” Tetrahedron, 69, 9726–9734 (2013).
  40. Iwano, S.; Obata, R.; Miura, C.; Kiyama, M.; Hama, K.; Nakamura, M.; Amano, Y.; Kojima, S.; Hirano, T.; Maki, S.; Niwa, H., “Development of simple firefly luciferin analogs emitting blue, green, red, and near-infrared biological window light,” Tetrahedron, 69, 3847–3856 (2013).
  41. Hirano, T.; Nakagawa, T.; Kodaka, A.; Maki, S.; Niwa, H.; Yamaji, M., “5-[4-(Dimethylamino)phenyl]-2-benzamidopyrazines: Fluorescent dyes based on Cypridina oxyluciferin,” Res. Chem. Intermed., 39, 233–245 (2013).
  42. Hirano, T.; Nagai, H.; Matsuhashi, T.; Hasumi, Y.; Iwano, S.; Ito, K.; Maki, S.; Niwa, H.; Viviani, V. R., "Spectroscopic studies of the color modulation mechanism of firefly (beetle) bioluminescence with amino-analogs of luciferin and oxyluciferin," Photochem. Photobiol. Sci., 11. 1281-1284 (2012).
  43. Hirano, T.; Nakagawa, T.; Kodaka, A.; Maki, S.; Niwa, H.; Yamaji, M., "5-[4-(Dimethylamino)phenyl]-2-benzamidopyrazines: Fluorescent dyes based on Cypridina oxyluciferin," Res. Chem. Intermed., in press.
  44. Hirano, T., "The reaction mechanism of calcium-activated photoprotein bioluminescence," Curr. Pharm. Biotech., in press.
  45. Ohashi, Y.; Kubota, M.; Hatase, H.; Hirano, T.; Maki, S.; Niwa, H., "Studies on (-) ESI-MS/MS of a glycosaminoglycan disaccharide N-acetyllactosamine-6, 6'-disulfate disodium salt-Charge-localization isomers," Int. J. Mass Spectrom., 312, 179-184 (2012).
  46. Mori, K.; Kojima, S.; Maki, S.; Hirano, T.; Niwa, H., "Bioluminescence characteristics of the fruiting body of Mycena chlorophos," Luminescence, 26, 604-610 (2011).
  47. Saito, R.; Hirano, T.; Maki, S.; Niwa, H.; M. Ohashi, M. "Influence of Electron-Donating and Electron-Withdrawing Substituents on the Chemiluminescence Behavior of Coelenterazine Analogs," Bull. Chem. Soc. Jpn., 84, 90-99 (2011).
  48. Hirano, T.; Sekiguchi, T.; Hashizume, D.; Ikeda, H.; Maki, S.; Niwa, H. "Colorimetric and fluorometric sensing of the Lewis acidity of a metal ion by metal-ion complexation of imidazo[1,2-a]pyrazin-3(7H)-ones," Tetrahedron, 66, 3842-3848 (2010).
  49. Hachiya, S.; Inagaki, T.; Hashizume, D.; Maki, S.; Niwa, H.; Hirano T. "Synthesis and fluorescence properties of difluoro[amidopyrazinato-O, N]boron derivatives: a new boron-containing fluorophore," Tetrahedron Lett., 51, 1613-1615 (2010).
  50. Hachiya, S.; Hashizume, D.; Maki, S.; Niwa, H.; Hirano T. "Synthesis and properties of bis(pyrazino[2',3':4,5]imidazole)-fused 1,2,5,6-tetrahydro-1,4,5,8,9,10-hexaazaanthracenes: a new fluorescent nitrogen-rich heterocycle," Tetrahedron Lett., 51, 1401-1403 (2010).
  51. Ohashi, Y.; Kubota, M.; Hatase, H.; Nakamura, M.; Hirano, T.; Niwa, H.; Nagai, Y. "Distinction of Sialyl Anomers on ESI- and FAB-MS/MS: Stereo-Specific Fragmentations," J. Am. Soc. Mass Spectrom., 20, 394-397 (2009).
  52. Hirano, T.; Hasumi, Y.; Ohtsuka, K.; Maki, S.; Niwa, H.; Yamaji, M.; Hashizume, D. "Spectroscopic Studies of the Light-Color Modulation Mechanism of Firefly (Beetle) Bioluminescence," J. Am. Chem. Soc., 131, 2385-2396 (2009).
  53. Hirano, T.; Takahashi, Y.; Kondo, H.; Maki, S.; Kojima, S.; Ikeda, H.; Niwa, H. "The reaction mechanism for the high quantum yield of the Cypridina (Vargula) bioluminescence supported by chemiluminescence of 6-aryl-2-methylimidazo[1,2-a]pyrazin-3(7H)-ones (Cypridina luciferin analogues)," Photochem. Photobiol. Sci., 7, 197-207 (2008).
  54. Namai, H.; Ikeda, H.; Hirano, T.; Ishii, H.; Mizuno, K. "Spectroscopic and Density Functional Theory Studies of the Molecular Geometry and Electronic Structure of Classical and Nonclassical Radical Ions Derived from 7-Benzhydrylidenenorbornene Analogues," J. Phys. Chem. A, 111, 7898-7905 (2007).
  55. Takahashi, Y.; Kondo, H.; Maki, S.; Niwa, H.; Ikeda, H.; Hirano, T. "Chemiluminescence of 6-aryl-2-methylimidazo[1,2-a]pyrazin-3(7H)-ones in DMSO/TMG and in diglyme/acetate buffer: support for the chemiexcitation process to generate the singlet-excited state of neutral oxyluciferin in high quantum yield in the Cypridina (Vargula) bioluminescence mechanism," Tetrahedron Lett., 47, 6057-6061 (2006).
  56. Mori, K.; Maki, S.; Niwa, H.; Ikeda, H.; Hirano, T. "Real light emitter in the bioluminescence of the calcium-activated photoproteins aequorin and obelin: light emission from the singlet-excited state of coelenteramide phenolate anion in a contact ion pair," Tetrahedron, 62, 6272-6288 (2006).
  57. Suzuki, M.; Fujii, T.; Nogami, T.; Hirano, T.; Ishida, T. "Bio-inspired Materials for Electron Donors and Charge-transfer Complex Formation Based on the Imidazopyrazinone Luciferin Core," Chem. Lett., 35, 250-251 (2006).
  58. Nakamura, M.; Niwa, K.; Maki, S.; Hirano, T.; Ohmiya, Y.; Niwa, H. "Construction of a new firefly bioluminescence system using L-luciferin as substrate," Tetrahedron Lett., 47, 1197-1200 (2006).
  59. Ohashi, Y.; Hatase, H.; Nakamura, M.; Hirano, T.; Maki, S.; Niwa, H. "Characterization of [1-13C]- Specifically Labeled Amino Acids Using ESIMS/MS in the Selected Reaction Monitoring Mode," J. Mass Spectrom. Soc. Jpn., 53, 309-314 (2005).
  60. Kondo, H.; Igarashi, T.; Maki, S.; Niwa, H.; Ikeda, H.; Hirano, T. "Substituent effects on the kinetics for the chemiluminescence reaction of 6-arylimidazo[1,2-a]pyrazin-3(7H)-ones (Cypridina luciferin analogues): support for the SET-oxygenation mechanism with triplet molecular oxygen," Tetrahedron Lett., 46, 7701-7704 (2005).
  61. Ikeda, H.; Namai, H.; Hirano, T. "Spectroscopic and DFT studies of nonclassical and classical radical cations of 7-benzhydrylidenenorbornene analogues: contrasting molecular geometry and electronic structures originating from the different patterns of electronic coupling," Tetrahedron Lett., 46, 7631-7635 (2005).
  62. Takamuki, Y.; Maki, S.; Niwa, H.; Ikeda, H.; Hirano, T. "Substituent effects on the spectroscopic properties of solvatochromic 2-phenylimidazo[1,2-a]pyrazin-3(7H)-ones: an effective control for the colorimetric sensor properties," Tetrahedron, 61, 10073-10080 (2005).
  63. Nakamura, M.; Maki, S.; Amano, Y.; Ohkita, Y.; Niwa, K.; Hirano, T.; Ohmiya, Y.; Niwa, H. "Firefly luciferase exhibits bimodal action depending on the luciferin chirality," Biochem. Biophys. Res. Commun., 331, 471-475 (2005).
  64. Ikeda, H.; Namai, H.; Hirano, T. "Spectroscopic and DFT evidence for a nonclassical radical cation derived from 7-benzhydrylidenenorbornene," Tetrahedron Lett., 46, 3917-3921 (2005).
  65. Nakamura, M.; Mamino, M.; Masaki, M.; Maki, S.; Matsui, R.; Kojima, S.; Hirano, T.; Ohmiya, Y.; Niwa, H., "Bioluminescence activity of Latia luciferin analogues: replacement of the 2,6,6-trimethylcyclohexene ring onto the methyl-substituted phenyl groups," Tetrahedron Lett., 46, 53-56 (2005).
  66. Takamuki, Y.; Maki, S.; Niwa, H.; Ikeda, H.; Hirano, T. "Substituent Effects on the Solvatochromism of 2-Phenylimidazopyrazinones: Effective Control of the Color Variation Range and Sensitivity toward an Indication of the Proton-Donor Ability of Solvents by an Electron-withdrawing Group Substitution," Chem. Lett., 33, 1484-1485 (2004).
  67. Fujio, S.; Hashizume, D.; Takamuki, Y.; Yasui, M.; Iwasaki, F.; Maki, S.; Niwa, H.; Ikeda, H.; Hirano, T. "Regioselective phenyl-substitution effects on the solvatochromism of 2-phenylimidazo[1,2-a]pyrazin-3(7H)-one derivatives: Expansion of the color variation range of a visible indicator for the proton donor ability of solvents," Tetrahedron Lett., 45, 8531-8534 (2004).
  68. Ohashi, Y.; Itoh, Y.; Kubota, M.; Hamada, K.; Ohashi, M.; Hirano, T.; Niwa, H. "Analysis of sugar epimers using mass spectrometry: N-acetyllactosamine-6,6’-disulfate and the 2’-epimer," Eur. J. Mass Spectrom., 10, 269-278 (2004).
  69. Nakamura, M.; Masaki, M.; Maki, S.; Matsui, R.; Hieda, M.; Mamino, M.; Hirano, T.; Ohmiya, Y.; Niwa, H., "Synthesis of Latia luciferin benzoate analogues and their bioluminescent activity," Tetrahedron Lett., 45, 2203-2205 (2004).
  70. Sekiguchi, T.; Maki, S.; Niwa, H.; Ikeda, H.; Hirano, T., "Metal-ion Complexation of Imidazo[1,2-a]pyrazin-3(7H)-ones: Continuous Changes in Absorption Spectra of Complexes Depending on the Lewis Acidity of a Metal Ion," Tetrahedron Lett., 45, 1065-1069 (2004).
  71. Nakai, S.; Yasui, M.; Nakazato, M.; Iwasaki, F.; Maki, S.; Niwa, H.; Ohashi, M.; Hirano, T., "Fundamental Studies on the Structures and Spectroscopic Properties of Imidazo[1,2-a]pyrazin-3(7H)-one Derivatives," Bull. Chem. Soc. Jpn., 76, 2361-2387 (2003).
  72. Maki, S.; Okawa, M.; Makii, T.; Hirano, T.; Niwa, H. "Pd Black Deposited on Polypropylene Sheet as a Selective Catalyst for Hydrogenation of Alkenes," Tetrahedron Lett., 44, 3717-3721 (2003).
  73. Maki, S.; Okawa, M.; Makii, T.; Hirano, T.; Niwa, H. "Hydrogenolysis-free Hydrogenation Using Pd Black Catalyst Deposited on Pd Sheet," ITE Lett., 4, 49-54 (2003).
  74. Obitsu, K.; Maki, S.; Hirano, T.; Niwa, H. "Preparation and Toxic Property of Carbapicrotoxinin, a Cyclopropane-containing Analog of a GABA-antagonistic Sesquiterpenoid Piricrotoxinin," ITE Lett., 3, 72-75 (2002).
  75. Kummer, A. D.; Kompa, C.; Niwa, H.; Hirano, T.; Kojima, S.; Michel-Beyerle, M. E. "Viscosity-Dependent Fluorescence Decay of the GFP Chromophore in Solution Due to Fast Internal Conversion," J. Phys. Chem. B, 106, 7554-7559 (2002).
  76. Itoh, Y.; Ohashi, Y.; Shibue, T.; Hayashi, A.; Maki, S.; Hirano, T.; Niwa, H. "Reduction in Desorption Mass Spectrometry: Multiple Protonation on Flavins without Charge Increment," J. Mass Spectrom. Soc. Jpn., 50, 52-57 (2002).
  77. Obitsu, K.; Maki, S.; Hirano, T.; Niwa, H. "Preparation of Deoxygenated Derivatives of Neoanisatin, a Neurotoxic Sesquiterpenoid Having a β-Lactone," Bull. Chem. Soc. Jpn., 75, 347-354 (2002).
  78. Imai, Y.; Shibata, T.; Maki, S.; Niwa, H.; Ohashi, M.; Hirano, T. "Fluorescence Properties of Phenolate Anions of Coelenteramide Analogues: the Light-emitter Structure in Aequorin Bioluminescence," J. Photochem. Photobiol. A, 146, 95-107 (2001).
  79. Maki, S.; Harada, Y.; Matsui, R.; Okawa, M.; Hirano, T.; Niwa, H.; Koizumi, M.; Nishiki, Y.; Furuta, T.; Inoue, H.; Iwakura, C. "Effect of Solvent and Hydrogen during Selective Hydrogenation," Tetrahedron Lett., 42, 8323-8327 (2001).
  80. Maki, S.; Okawa, M.; Matsui, R.; Hirano, T.; Niwa, H. "Hydrogenolysis-free Hydrogenation by Pd Black Powder Catalyst," Synlett, 1590-1592 (2001).
  81. Kojima, S.; Maki, S.; Hirano, T.; Ohashi, M.; Tsuji, F. I.; Niwa, H. "Improved Syntheses of Watasenia Preluciferin (Coelenterazine) and Watasenia Luciferin (Coelenterazine Disulfate), and Site Specific Syntheses of the Coelenterazine Monosulfates," ITE Lett., 2, 393-397 (2001).
  82. Ishii, H.; Imai, Y.; Hirano, T.; Maki, S.; Niwa, H.; Ohashi, M. " Isoquinoline Formation by a Novel Photochemical Intermolecular Cycloaddition of 1,1-Diphenylethene Derivatives to 1,4-Dicyanobenzene," Tetrahedron Lett., 41, 6467-6471 (2000).
  83. Maki, S.; Harada, Y.; Hirano, T.; Niwa, H.; Yoshida, Y.; Ogata, S.; Nakamatsu, S.; Inoue, H.; Iwakura, C. "Selective Alkene Hydrogenation with Atomic Hydrogen Permeating through a Pd Sheet Electrode," Syn. Commun., 30, 3575-3583 (2000).
  84. Kojima, S.; Maki, S.; Hirano, T.; Ohmiya, Y.; Niwa, H. "Bioluminescence Activity of Latia Luciferin Analogs," Tetrahedron Lett., 41, 409-4413 (2000).
  85. Hirano, T.; Li, W.; Abrams, L.; Krusic, P. J.; Ottaviani, M. F.; Turro, N. J. "Supramolecular Steric Effect As The Means of Making Reactive Carbon Radicals Persistent; Quantitative Characterization of The External Surface of MFI Zeolites through A Persistent Radical Probe and A Langmuir Adsorption Isotherm," J. Org. Chem., 65, 1319-1330 (2000).
  86. Jockusch, S.; Hirano, T.; Liu, Z.; Turro, N. J. "A Spectroscopic Study of Diphenylmethyl Radicals and Diphenylmethyl Carbocations Stabilized by Zeolites," J. Phys. Chem. B, 104, 1212-1216 (2000).
  87. Zheng, J. L.; Chen, F. Q.; Hirano, T.; Ohmiya, Y.; Maki, S.; Niwa, H.; Ohashi, M. "Synthesis, Chemi- and Bioluminescence Properties, and Photolysis of a Coelenterazine Analogue Having a Photoactive Azido Group," Bull. Chem. Soc. Jpn., 73, 465--469 (2000).