Table 1 Photochemical properties of (6-bromo-7-hydroxy-4-hydroxy-
methyl)coumarin 4 and Bhc-caged ceramide 16
ceramide’s N-acyl chain structure in distinct intracellular
signaling pathways in both physiological and pathophysio-
logical events.
l
abs(e)a
lem
Solventc
b
Ffl
This research was supported by NIH Grant HL083187.
DMCR and LJJ acknowledge support from an Ontario Graduate
Scholarship and the Natural Sciences and Engineering
Research Council. We thank Spencer P. Pitre for assistance
with the HPLC analysis and fluorescence imaging.
4
366 (13 600)
343, 374d
338, 4380 (sh)
466
467
466
0.47
0.50
0.02
A
B
B
16
a
b
Extinction coefficient (cmÀ1 MÀ1). Quantum yields of fluorescence
for excitation at 374 nm, with reference to Coumarin 460 (Ffl = 0.59).
Solvent A: KMops (pH 7.4), Solvent B: KMops (pH 7.4) containing
c
d
50% ethanol. Coexistence of protonated (343 nm) and deprotonated
(374 nm) forms of 4.
Notes and references
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consistent with its expected photochemical reactivity. The
stability of 16 in aqueous buffer in the dark at 25 1C was
examined by HPLC, which showed a half-life of B30 h (see
ESIw), in good agreement with the stability reported for
another carbonate-linked photocage.13a
Fig. 1A shows the loss of starting material 16 and generation
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14 Bhc-OAc and 8-bromo-2-hydroxyquinoline (BHQ-OAc) pre-
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Fig. 1 Time course of photolysis of Bhc-caged ceramide 16 in
KMops (pH 7.4) on 350-nm irradiation in a Rayonet photochemical
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c
9238 Chem. Commun., 2011, 47, 9236–9238
This journal is The Royal Society of Chemistry 2011