W0 2011/000721 A1 I||||||||||||||||||||||||||||||||||||||||||||||||||||||||| - Questel

3H, CH 3 CO), 1.99 (s, 3H, CH 3 CO), 1.91-1 .83 (m, 1H, D 6eq ), 1.83-1.75 (m, 1H,
D 3eq ). 13 C-NMR (100 MHz, CDCI 3 ) δ (ppm): 174.57, 174.52 (COOCH 3 ), 170.10,
169.92 (CH 3 CO), 97.62 (C1 M ), 78.55 (C1 D ), 70.22 (C5 M ), 69.47 (C2 M ), 69.07
(C3M/C4 M ) , 68.13 (C2 D ), 67.78 (C6 M ), 67.03 (C7), 66.42 (C3M/C4 M ), 52.04
(OCH 3 ), 50.43 (C8), 39.61 (C5 D ), 39.28 (C4 D ), 30.48 (C3 D ), 27.03 (C6 D ), 20.88,
20.83, 20.71 (CH 3 CO). HRMS (ESI): Calculated for [C 24 H 35 N 3 O 14 Na] + =
612.201 12 Experimental = 612.19995.
3) Synthesis of the α(1,2) α( 1 ,6)pseudomannotriose 9
A mixture of the acceptor 7 (53.2 mg, 0.0902 mmol, 1 eq) and the donor 8
(80.2 mg, 0.1083 mmol, 1.2 eq) was co-evaporated with toluene three times,
then powdered molecular sieves 4A acid washed were added; the mixture was
kept under vacuum for few hours and then dissolved with dry CH 2 C I ( 1 .8 ml_).
After cooling at -20 0 C, TMSOTf (3 μl, 0.018 mmol, 0.2 eq.) was added and the
reaction mixture was stirred at that temperature. The reaction was monitored
by TLC (7:3 CH 2 CI 2 :Et0Ac and 7:3 Toluene:EtOAc): after 20 minutes the
reaction was finished.
In order to quench the reaction NEt 3 was added. The mixture was brought to
room temperature and filtered over a celite pad, then the solvent was
evaporated at reduced pressure obtaining 140 mg of crude as a white solid.