"Photo" Chemistry Without Light?
Open accessAbstract
In the early seventies, Giuseppe Cilento (São Paulo University), Emil White (Johns Hopkins University) and Angelo Lamola (AT&T Bell Laboratories) postulated that typical photochemical reactions could occur in dark parts of living organisms if coupled to enzymatic sources of electronically excited products. Their paradoxical hypothesis of "photochemistry without light" was chemically anchored on the synthesis and weak chemiluminescence of several 1,2-dioxetanes, unstable cyclic peroxides whose thermal cleavage produces long-lived and reactive triplet carbonyls. Collisional reactions or energy transfer of triplet species to cellular targets could eventually result in "photo" products that potentially trigger normal or pathological responses. These ideas flourished in the labs of various researchers who attempted to explain the presence and biological roles of "dark" secondary metabolites, including plant hormones, pyrimidine dimers, alkaloid lumi-isomers, protein adducts, and mitochondrial permeators, thereby broadening the field of photobiology.
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In vivo roles for these chemiexcited processes in mammals remained elusive.
“Yet, in vivo roles for these processes in mammals remained elusive”
From Chemiexcitation: Mammalian Photochemistry in the Dark<sup>†</sup> (2023) · cites this paper as [16]
Dioxetanes or dioxetanones are created in three ways.
“Dioxetanes or dioxetanones are created in three ways”
From Chemiexcitation: Mammalian Photochemistry in the Dark<sup>†</sup> (2023) · cites this paper as [16]
The triplet carbonyl has several energy dissipation options, some harmless and some detrimental.
“The triplet carbonyl has several options, some harmless and some detrimental (16) (Fig. 6).”
From Chemiexcitation: Mammalian Photochemistry in the Dark<sup>†</sup> (2023) · cites this paper as [16]
Cites
Modern Molecular Photochemistry of Organic Molecules
Steinmetz, M. (2010) · Journal of the American Chemical Society · doi:10.1021/ja1036176 · Cited by 88 · cited 1× · see citing works
“Excited aldehydes and ketones decay by a variety of processes from the singlet as well as the triplet manifold, which encompass homolytic C−C bond cleavage (α- and β-cleavage), hydrogen abstraction (photoreduction), [2 + 2] cycloadditions (Paternò-Büchi reaction), quenching by conjugated dienes, and others (Figure 5).…”
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Endogenous Photosensitizers in Human Skin.
Bastos, E., Quina, F., & Baptista, M. S. (2023) · Chemical Reviews · doi:10.1021/acs.chemrev.2c00787 · Cited by 69 · see citing works
Chemical excitation of electrons: A dark path to melanoma
Premi, S., & Brash, D. E. (2016) · DNA Repair · doi:10.1016/j.dnarep.2016.05.023 · Cited by 47 · see citing works
Chemiexcitation and Its Implications for Disease
Brash, D. E., Gonçalves, L. C. P., & Bechara, E. J. H. (2018) · Trends in Molecular Medicine · doi:10.1016/j.molmed.2018.04.004 · Cited by 36 · see citing works
Self-citationVentura, F. F., Mendes, L., Oliveira, A. G., Bazito, R., Bechara, E., Freire, R. S., & Stevani, C. V. (2020) · Environmental Toxicology and Chemistry · doi:10.1002/etc.4740 · Cited by 26
“Fungal bioluminescent assay and phenolic compounds toxicity Bioluminescence depends on molecular oxygen to occur and therefore is closely connected to respiratory activity (Barros and Bechara 1998; Baader et al. 2015; Bechara et al. 2017).”
BackgroundSelf-citationSouza, S. P., Khalid, M., Augusto, F., & Baader, W. (2016) · Journal of Photochemistry and Photobiology A Chemistry · doi:10.1016/j.jphotochem.2016.02.001 · Cited by 18 · see citing works
Self-citationCarpenter, E. L., Le, M., Miranda, C., Reed, R., Stevens, J., Indra, A., & Ganguli-Indra, G. (2018) · Frontiers in Pharmacology · doi:10.3389/fphar.2018.00477 · Cited by 17 · see citing works
“…might involve ROS-mediated formation of dioxetane intermediates, as has been postulated for the formation of CPDs in the dark after UVB irradiation of melanocytes followed by exothermic energy transfer of high-energy melanin products to adjacent thymine and cytosine bases (Baader et al., 2015).”
BackgroundChemiexcitation: Mammalian Photochemistry in the Dark<sup>†</sup>
Brash, D. E., & Goncalves, L. C. P. (2023) · Photochemistry and Photobiology · doi:10.1111/php.13781 · Cited by 16 · see citing works
“has several options, some harmless and some detrimental (16) (Fig.”
BackgroundInfluentialJosef, B. W., Khalid, M., Souza, S. P., Cabello, M., Bartoloni, F., Ciscato, L. F. L. M., Bastos, E., & Seoud, O. E. E. (2022) · Social Science Research Network · doi:10.2139/ssrn.4136472 · Cited by 14
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Marazzi, M., Gattuso, H., Giussani, A., Zhang, H., Navarrete‐Miguel, M., Chipot, C. J., Cai, W., Roca‐Sanjuán, D., Dehez, F., & Monari, A. (2019) · The Journal of Physical Chemistry Letters · doi:10.1021/acs.jpclett.9b02911 · Cited by 17 · see citing works
Total Synthesis of (±)-Sceptrin
Nguyen, L. V., & Jamison, T. (2020) · Organic Letters · doi:10.1021/acs.orglett.0c01381 · Cited by 13
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Cabello, M., Souza, G. A., Bello, L. V., & Baader, W. (2019) · Photochemistry and Photobiology · doi:10.1111/php.13180 · Cited by 12
Self-citationShining a Light on Bioorthogonal Photochemistry for Polymer Science.
Boase, N. R. B. (2020) · Macromolecular rapid communications · doi:10.1002/marc.202000305 · Cited by 9 · see citing works
Mining reactive triplet carbonyls in biological systems.
Ramos, L. D., Gomes, T. M. V., Stevani, C. V., & Bechara, E. (2023) · Journal of Photochemistry and Photobiology. B: Biology · doi:10.1016/j.jphotobiol.2023.112712 · Cited by 7 · see citing works
Self-citationHughes, W. B., Popescu, M. V., & Paton, R. S. (2026) · Journal of Chemical Theory and Computation · doi:10.1021/acs.jctc.6c00144 · Cited by 6
Anderson, T., Andia, A., & Woerpel, K. (2020) · Tetrahedron · doi:10.1016/j.tet.2020.131874 · Cited by 6
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Ramos, L. D., Prado, F., Stevani, C. V., di Mascio, P., & Bechara, E. (2020) · Photochemistry and Photobiology · doi:10.1111/php.13363 · Cited by 5 · see citing works
“tone, such as 2-propanol and pinacol (4,6,43) To evaluate the extent of protein chemical modifications triggered by radical products of the IBAL/HRP reaction, SDS-PAGE”
BackgroundSelf-citationKodamatani, H., Yoshimine, D., Fujioka, T., Kanzaki, R., & Tomiyasu, T. (2021) · doi:10.1016/j.talo.2021.100035 · Cited by 4
Braslavsky, S., & Previtali, C. (2025) · Photochemistry and Photobiology · doi:10.1111/php.14044 · Cited by 2 · see citing works
How Tryptophan Oxidation Arises by “Dark” Photoreactions from Chemiexcited Triplet Acetone
O'Connor, R. M., & Greer, A. (2021) · Photochemistry and Photobiology · doi:10.1111/php.13375 · Cited by 2 · see citing works
Understanding the Misunderstood
Schneider, C. (2019) · Recent Advances in Polyphenol Research · doi:10.1002/9781119427896.ch12 · Cited by 2 · see citing works
Ito, S., Sok, J., Nakanishi, Y., Wakamatsu, K., & Bino, S. D. (2026) · International Journal of Molecular Sciences · doi:10.3390/ijms27093973 · Cited by 1 · see citing works
Kazakov, D., Nazyrov, T. I., Safarov, F., Yaremenko, I., & Terent'ev, A. (2019) · Photochemical and Photobiological Sciences · doi:10.1039/c8pp00472b · Cited by 1 · see citing works
Gomes, T. M. V., Stevani, C. V., Pantopoulos, K., Ramos, L. D., & Bechara, E. (2026) · Luminescence (Chichester, England Print) · doi:10.1002/bio.70618
“Previous studies reported that triplet acetone can abstract hydrogen from the carbohydrate moiety of the HRP (18%), leading to oxidative damage [51].”
Self-citationPhotodissociation of 1,2-dioxetane: An excited state nonadiabatic dynamics study
Hilal, R. (2022) · Journal of the Indian Chemical Society · doi:10.1016/j.jics.2022.100440
- Authors
- Baader, W. J., Stevani, C. V., & Bechara, E. J. H.
- Affiliations
- Universidade de São Paulo (BR)
- Venue
- Journal of the Brazilian Chemical Society
- Published
- 2015
- ISSN
- 0103-5053 (ISSN-L)
- OpenAlex
- W1985421207
- Cited by
- 24
- References
- 3
- Citations by year
- 2026: 1 · 2025: 1 · 2023: 2 · 2022: 4 · 2021: 2 · 2020: 5 · 2019: 4 · 2018: 3 · 2016: 2
- FWCI
- 0.72
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- cc-by
- Locations
- Journal of the Brazilian Chemical Society (publishedVersion, cc-by)
- LA Referencia (Red Federada de Repositorios Institucionales de Publicaciones Científicas) (publishedVersion, other-oa)
- Americanae (AECID Library) (submittedVersion, cc-by-nc)
- Funders
- Fundação de Amparo à Pesquisa do Estado de São Paulo (2014-22136-4, 2014/, 08/57721-3, 2014/22136)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › bioluminescence and chemiluminescence research
- Physical Sciences › Chemistry › Physical and Theoretical Chemistry › Chemical Reactions and Mechanisms
- Physical Sciences › Chemistry › Physical and Theoretical Chemistry › Photochemistry and Electron Transfer Studies
- Keywords
- 1,2-dioxetanes, chemiluminescence, cyclic peroxides, energy transfer, photobiology, pyrimidine dimers, plant hormones, protein adducts
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