(2'S,3'R,4'S,5'R,6'R)-3',4',5'-tris(benzyloxy)-6'-(benzyloxymethyl)-7-chloro-6-(4-ethylbenzyl)-2-methyl-3',4',5',6'-tetrahydrospiro[chroman-4,2'-pyran]-2-ol → (2'S,3'R,4'S,5'S,6'R)-7-chloro-6-(4-ethylbenzyl)-6'-(hydroxymethyl)-2-methyl-3',4',5',6'-tetrahydrospiro[chroman-4,2'-pyran]-2,3',4',5'-tetraol

Participants

Reaction Steps

To a solution of 45 (30 mg, 36.3 μmol) in a mixture of MeOH (3.0 mL) and THF (1 mL) was added Pd(OH)2/C (30 mg). A balloon of hydrogen gas was attached for 0.5 h with vigorous stirring. LC/MS indicated that de-protection was complete. The aromatic chloride was partially cleaved. The reaction mixture was filtered through Celite, concentrated to a residue, and purified by preparatory HPLC to give 53 (5.8 mg, 34%). 1H NMR (300 MHz, CD3OD) δ 7.50 (s, 1H), 7.00-7.07 (m, 4H), 6.77 (s, 1H), 3.98 (s, 2H), 3.93 (dd, J=2.1, 11.7 Hz, 1H), 3.65-3.82 (m, 3H), 3.55 (dd, J=8.1, 9.6 Hz, 1H), 3.27 (t, J=9.6 Hz, 1H), 2.80 (d, J=11.1 Hz, 1H), 2.57 (q, J=7.5 Hz, 2H), 1.96 (d, J=11.4 Hz, 1H), 1.68 (s, 3H), 1.19 (t, J=7.5 Hz, 3H). LC/MS m/z 447 (M−OH).

Provenance & Evidence