Competing Pathways in the Photo-Favorskii Rearrangement and Release of Esters: Studies on Fluorinated p-Hydroxyphenacyl-Caged GABA and Glutamate Phototriggers

STENSRUD, Kenneth F., Jihyun NOH, Karl KANDLER, Jakob WIRZ, Dominik HEGER a Richard GIVENS. Competing Pathways in the Photo-Favorskii Rearrangement and Release of Esters: Studies on Fluorinated p-Hydroxyphenacyl-Caged GABA and Glutamate Phototriggers. JOURNAL OF ORGANIC CHEMISTRY. 2009, roč. 74, č. 15, s. 5219-5227. ISSN 0022-3263.

Základní údaje

• Originální název: Competing Pathways in the Photo-Favorskii Rearrangement and Release of Esters: Studies on Fluorinated p-Hydroxyphenacyl-Caged GABA and Glutamate Phototriggers
• Název česky: Competing Pathways in the Photo-Favorskii Rearrangement and Release of Esters: Studies on Fluorinated p-Hydroxyphenacyl-Caged GABA and Glutamate Phototriggers
• Autoři: STENSRUD, Kenneth F. (840 Spojené státy), Jihyun NOH (840 Spojené státy), Karl KANDLER (840 Spojené státy), Jakob WIRZ (756 Švýcarsko), Dominik HEGER (203 Česká republika, garant) a Richard GIVENS (840 Spojené státy).
• Vydání: JOURNAL OF ORGANIC CHEMISTRY, 2009, 0022-3263.

Další údaje

• Originální jazyk: angličtina
• Typ výsledku: Článek v odborném periodiku
• Obor: 10403 Physical chemistry
• Stát vydavatele: Spojené státy
• Utajení: není předmětem státního či obchodního tajemství
• Impakt faktor: Impact factor: 4.219
• Kód RIV: RIV/00216224:14310/09:00036419
• Organizační jednotka: Přírodovědecká fakulta
• UT WoS: 000268480300012
• Klíčová slova česky: RESOLVED RESONANCE RAMAN; PHOTOREMOVABLE PROTECTING GROUPS; DENSITY-FUNCTIONAL THEORY; TRIPLET-STATE; EXCITED-STATE; PHOTODEPROTECTION; SPECTROSCOPY; HYDROXYACETOPHENONE; ABSORPTION; ACTIVATION
• Klíčová slova anglicky: RESOLVED RESONANCE RAMAN; PHOTOREMOVABLE PROTECTING GROUPS; DENSITY-FUNCTIONAL THEORY; TRIPLET-STATE; EXCITED-STATE; PHOTODEPROTECTION; SPECTROSCOPY; HYDROXYACETOPHENONE; ABSORPTION; ACTIVATION
• Příznaky: Recenzováno

Anotace

Three new trifluoromethylated p-hydroxyphenacyl (pHP)-caged gamma-aminobutyric acid (GABA) and glutamate (Glu) derivatives have been examined for their efficacy as photoremovable protecting groups in aqueous solution. Through the replacement of hydrogen with fluorine, e.g., a m-trifluoromethyl or a m-trifluoromethoxy versus m-methoxy substituents on the pHP chromophore, modest increases in the quantum yields for the release of amino acids GABA and glutamate as well as improved lipophilicity were realized. The pH P triplet undergoes a photo-Favorskii rearrangement with concomitant release of the amino acid substrate. Deprotonation competes with the rearrangement from the triplet excited state and yields the pHP conjugate base that, upon reprotonation, regenerates the starting ketoester, a chemically unproductive or "energy-wasting" process. When picosecond pump-probe spectroscopy is employed, GABA derivatives 2-5 are characterized by short triplet lifetimes, a manifestation of their rapid release of GABA. The bioavailability of released GABA at the GABA(A) receptor improved when the release took place from m-OCF3 (2) but decreased for m-CF3 (3) when compared with the parent pHP derivative. These studies demonstrate that pK(a) and lipophilicity exert significant but sometimes opposing influences on the photochemistry and biological activity of pHP phototriggers.

Anotace česky

Three new trifluoromethylated p-hydroxyphenacyl (pHP)-caged gamma-aminobutyric acid (GABA) and glutamate (Glu) derivatives have been examined for their efficacy as photoremovable protecting groups in aqueous solution. Through the replacement of hydrogen with fluorine, e.g., a m-trifluoromethyl or a m-trifluoromethoxy versus m-methoxy substituents on the pHP chromophore, modest increases in the quantum yields for the release of amino acids GABA and glutamate as well as improved lipophilicity were realized. The pH P triplet undergoes a photo-Favorskii rearrangement with concomitant release of the amino acid substrate. Deprotonation competes with the rearrangement from the triplet excited state and yields the pHP conjugate base that, upon reprotonation, regenerates the starting ketoester, a chemically unproductive or "energy-wasting" process. When picosecond pump-probe spectroscopy is employed, GABA derivatives 2-5 are characterized by short triplet lifetimes, a manifestation of their rapid release of GABA. The bioavailability of released GABA at the GABA(A) receptor improved when the release took place from m-OCF3 (2) but decreased for m-CF3 (3) when compared with the parent pHP derivative. These studies demonstrate that pK(a) and lipophilicity exert significant but sometimes opposing influences on the photochemistry and biological activity of pHP phototriggers.

Návaznosti

• MSM0021622413, záměr: Název: Proteiny v metabolismu a při interakci organismů s prostředím

Investor: Ministerstvo školství, mládeže a tělovýchovy ČR, Proteiny v metabolismu a při interakci organismů s prostředím