J Fluoresc
Experiments
dichloromethane (10 mL) and consecutively washed with
H2O, 10% ammonia and H2O. The organic phase was dried
over Na2SO4 and evaporated. The crude product was purified
by column chromatography on silica eluting with dichloro-
methane: petroleum ether: ethyl acetate = 6:5:1 to afford the
title compound 1 as yellow oil (3.65 g, 65%).
Materials
3-aminophenol, methyl acrylate, 1-aminonaphthalene, 1-
naphthol, 1,6-naphthalenediol and all of organic solvent used
were of analytical grade.
1H NMR (500 MHz, DMSO-d6): δ 2.51 (t, J = 7.0 Hz, 4H),
3.49 (t, J = 7.0 Hz, 4H), 3.59 (s, 6H), 6.07–6.11 (m, 3H), 6.93
(s, 1H), 9.05 (s, br, 1H).
The H3BO3 buffer (pH = 8.5) was prepared by adding
1 mol/L HCl solution to 0.05 mol/L Na2B4O7 solution to the
required pH value. Phosphate buffered saline buffer (pH =
7.39) was prepared by dissolving 0.20 g KCl, 1.44 g
Na2HPO4, 0.24 g KH2PO4, and 8.00 g NaCl in 800 mL dis-
tilled water and adjusting the pH with 0.1 mol/L HCl solution,
then diluted to 1000 mL by distilled water. After sterilized at
120 °C, the buffer was stored at the room temperature.
Working standard of compound 6 or 9: compounds 6 and 9
were dissolved in PBS buffer as 100 μg/mL, respectively, and
then diluted to 0.5 or 0.1 μg/mL as the working solution.
Luria-Bertani (LB) Agar Broth was prepared by adding 6 g
of tryptone, 3 g of yeast extract, 6 g of NaCl and 9 g agar
powder to 600 mL distilled water. After sterilized for 30 min at
120 °C, LB Agar Broth was poured into dishes to cultivate
bacteria when cooled to 50 °C.
Dimethyl 3,3′-((3-hydroxy-4-nitrosophenyl)azanediyl)
dipropionate (2) [2]
Sodium nitrite (2.06 g, 29.9 mmol) in water (15.2 mL) was
stepwise added to a solution of compound 1 (7.82 g, 27.8 mmol)
in HCl (9.38 mL, 12.0 M) and water (4.70 mL) with stirring for
4 h in an ice bath. The mixture was filtered to remove residual
impurities. The filtrate was evaporated under reduced pressure.
The crude product dissolved in methanol was dried with
MgSO4, then filtered and concentrated to obtain compound 2
(6.48 g, 75.1%). This somewhat unstable nitroso compound
was directly used without further purification for the next step.
Bacteria used in this study: E. coli, Soil D. Bacillus
Polyfermenticus and Motile unit cell rod-shaped Bacteria
from Henan Key Laboratory of Crop Pest Control of Hong-
Yan Liu researcher.
9-(bis(3-methoxy-3-oxopropyl)amino)-5H-benzo[a]
phenoxazin-5-iminium chloride (3)
Compound 2 (2.12 g, 6.8 mmol), 1-naphthylamine (0.98 g,
6.8 mmol), and HCl (2.0 mL, 12.0 M) in 50 mL methanol
were refluxed for 7 h. The solvent was evaporated and the
residue was isolated by column chromatography on silica elut-
ing with the gradient elution of dichloromethane:methanol =
60:1~40:1~30:1 to give the title compound 3 (2.29 g, 80.8%)
as metallic green powder.
Characterization
1H NMR was performed on a INOVA 500 spectrometer with
tetramethylsilane as internal reference. UV-vis absorption
spectra were measured on a computer-controlled Shimadzu
UV-2450 spectrometer. Fluorescent microscope images of
bacteria stranules stained with compound 6 or 9 were recorded
with the invert fluorescent microscope IX71-A12FL/PH. The
pH values were determined with a pHS-25 acidimeter calibrat-
ed with standard aqueous buffer solutions. The fluorescence
spectra were measured in standard quartz cuvettes on a Cary
Eclipse or JASCO FP-750 spectrofluorimeter.
1H NMR (500 MHz, DMSO-d6): δ 2.70 (t, J = 7.0 Hz, 4H),
3.35 (s, 6H), 3.85 (t, J = 7.0 Hz, 4H), 6.99 (s, 1H), 7.07 (s, 1H),
7.22 (d, J = 9.5 Hz, 1H), 7.85 (d, J = 9.5 Hz, 1H), 7.89 (t, J =
8.0 Hz, 1H), 7.99 (t, J = 8.0 Hz, 1H), 8.55 (d, J = 8.0 Hz, 1H),
8.78 (d, J = 8.0 Hz, 1H).
Dimethyl 3,3′-((5-oxo-5H-benzo[a]phenoxazin-9-yl)
azanediyl)dipropionate (4)
Syntheses of Compounds 1–10
Compound 4 was similliarily synthesized as compound 3.
And compound 2 (5.16 g, 16.7 mmol), 1-naphthol (2.34 g,
16.7 mmol), HCl (4.87 mL, 12.0 M) and methanol (50 mL).
The residue was isolated by column chromatography on silica
eluting with dichloromethane:methanol = 150:1 to give the
title compound 4 (1.84 g, 58.5%) as red powder.
Two synthetic routes of diesters 3, 4 and 5 and dicarboxylic
acids 6, 9 and 10 are outlined in Schemes 1 and 2.
Dimethyl 3,3′-((3-hydroxyphenyl)azanediyl)dipropionate
(1) [41]
1H NMR (500 MHz, DMSO-d6): δ 2.63 (t, J = 7.0 Hz, 4H),
3.35 (s, 6H), 3.73 (t, J = 7.0 Hz, 4H), 6.29 (s, 1H), 6.73 (s, 1H),
6.84 (d, J = 9.0 Hz, 1H), 7.63 (d, J = 9.0 Hz, 1H), 7.72 (t, J =
7.0 Hz, 1H), 7.81 (t, J = 7.0 Hz, 1H), 8.11 (d, J = 7.5 Hz, 1H),
8.54 (d, J = 7.5 Hz, 1H).
A mixture of 3-aminophenol (2.18 g, 20.0 mmol), CuCl
(0.37 g, 3.7 mmol), acetic acid (2.40 g, 40.0 mmol) and meth-
yl acrylate (5.34 g, 62.1 mmol) was refluxed for 20 h. After
cooling to the room temperature, the mixture was diluted with