A. Taglienti et al. / Carbohydrate Research 344 (2009) 245–249
249
O
H
OH
O
O
3
7 °C
OH
O
HO
O
OH
O
HO
O
HO
HO
O
O
O
O
NH
NH
H COC
H COC
3
pH = 7.0
3
O
OH
CH2
CO
+
OH
HO
CH OH
2
CO
OH
H
H
HO
O
H
H
O
Scheme 2. Hydrolysis reaction of the ester bond of HYCp45 for the release of methylprednisolone at 37 °C and pH 7.0. The reaction was initiated by heating the solution.
soluble in water, and the solution shows nearly the same viscosity
deviations. The latter were obtained from the classical error prop-
agation combining the experimental errors of the measurements.
23
of pure water, as already shown in a previous work.
1
H NMR spectra were recorded by using the selective water
suppression according to a standard procedure.24 HDO signal was
saturated using a 3 s pulse having 45 dB intensity. Chemical shifts
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2
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4
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.3. Hydrolysis
2
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melting ice and transferred in the NMR tube for T measurement.
2
O at
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2