2025-95-8Relevant articles and documents
Energy transfer in bichromophoric molecules: The effect of symmetry and donor/acceptor energy gap
Yip,Levy, Donald H.,Kobetic, Renata,Piotrowiak, Piotr
, p. 10 - 20 (1999)
The dependence of the rate of singlet excitation transfer on the donor-acceptor energy gap was investigated in bichromophoric spiranes with symmetry-forbidden zero-order electronic coupling. The fluorescence measurements were performed in a supersonic jet in order to avoid collisional and inhomogeneous line broadening. Fluorescence excitation spectra and single-vibronic-level emission spectra of the model chromophores cyclopentaphenanthrene and 1,8-dimethylnaphthalene and the bichromophores spirofluorenephenanthrene and spirofluorenenaphthalene are presented and analyzed. Although the transition moments of the linked chromophores are rigorously perpendicular and the exchange coupling between the v′ = 0 states is computationally shown to be zero, all spiranes with energy gaps larger than ～1000 cm-1 exhibited complete electronic energy transfer from all vibrational states of the electronically excited donor, including the undistorted v′ = 0 state. This behavior is explained in terms of vibronic coupling between the sparse states of the donor and the dense manifold (pseudocontinuum) of the acceptor states. The electronic energy transfer was sufficiently fast to result in measurable lifetime broadening of the donor absorption lines, from which the kEET was estimated. The results demonstrate that the zero-order picture overestimates the degree of the molecular orbital symmetry control over electronic energy transfer and charge-transfer rates and that at sufficiently high driving forces the vibronically mediated "symmetry-forbidden" electronic energy transfer can be very rapid (～1 × 1012 s-1).
Synthesis of anti-4,5,14,15-Tetramethyl2>(2,7)naphthalenophane-1,11-diene and its Dianion. ESR and ENDOR Studies of its Radical Anion and Other Related Radical Ions
Rohrbach, William D.,Gerson, Fabian,Moeckel, Reinhart,Boekelheide, Virgil
, p. 4128 - 4132 (1984)
A synthesis of anti-4,5,14,15-tetramethyl2>(2,7)naphthalenophane-1,11-diene (4) has been achived in ten steps from 1,8-naphthalic anhydride in an overall yield of 4percent.The key step in the synthesis employed a double-barreled sulfur analogue of the Sommelet-Hauser rearrangement.Unexpectedly, formation of the dianion and radical anion of 4 occured without intramolecular cyclization.The radical anions and the radical cations both of 4 and of anti-4,5,14,15-tetramethyl2>(2,7)naphthalenophane (19) have been characterized by ESR and ENDOR spectroscopy.
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Bergmann,Szmuszkovicz
, p. 2760 (1953)
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Unique behavior of 2,6-bis(bromomethyl)naphthalene as a highly active organic DNA crosslinking molecule
Higashi, Toshinori,Uemura, Koichi,Inami, Keiko,Mochizuki, Masataka
, p. 3568 - 3571 (2009)
Among 14 bis-halomethylated naphthalenes and quinolines, 2,6-bis(bromomethyl)naphthalene was found to have highly active crosslinking activity on DNA. The unique behavior of high microbial mutagenicity, even though it had a low propensity to form double-strands in linearized plasmid DNA, suggested that it would offer a new seed, capable of forming intrastrand crosslinks similar to cisplatin. The electron withdrawal extent of the halogen atoms, the substitution patterns of two halomethyl groups, and the introduction of a nitrogen atom into the aromatic nucleus had remarkable effects on the activity of the molecule.
1-Aminobenzocyclobutene-1-phosphonic Acid and Related Compounds as Inhibitors of Phenylalanine Ammonia-Lyase
Zoń, Jerzy,Miziak, Piotr
, (2017/05/17)
Five new geminal aminocycloalkanephosphonic acids (4 – 8) containing both an aromatic ring and a cycloalkane ring were synthesized and evaluated as potential inhibitors of buckwheat phenylalanine ammonia-lyase (PAL). Within the set of compounds which are related to 2-aminoindane-2-phosphonic acid (AIP, 3), a known powerful inhibitor of PAL, racemic 1-aminobenzocyclobutene-1-phosphonic acid (4), was six times weaker than AIP as an in vitro inhibitor of buckwheat PAL, but six times stronger than AIP as an in vivo inhibitor of phenylalanine-derived anthocyanin synthesis in buckwheat.
Synthesis and properties of dicarboximide derivatives of perylene and azaperylene
Nagao, Yukinori,Yoshida, Tatsurou,Arimitsu, Koji,Kozawa, Kozo
experimental part, p. 1197 - 1213 (2010/10/04)
The N-alkyl dicarboximide derivatives of naphthylisoquinoline and binaphthalene were prepared by the hetero coupling reaction of the corresponding N-alkyl dicarboximide derivatives of stannylnaphthalene with bromodimethyisoquinoline and bromodimethylnaphthalene, respectively. The ring closing of the N-hexyl derivatives of naphthylisoquinoline and binaphthalene produced the N-hexyldicarboximide derivatives of azaperylene and perylene having the same substituents, respectively. The absorption spectra and fluorescence spectra of the azaperylene and perylene derivatives were investigated.
