Glycosyl Trichloroacetimidates
3.2
511
⊡ Scheme 41
⊡ Scheme 42
synthesis the hydroxymethyl group is selectively oxidized to the carboxylate group. Excellent results in direct glucuronidation based on O-isobutyryl-protected trichloroacetimidate
have been obtained by Scheinmann and Stachulski et al., who glucuronidated for instance
an anti-estrogenic steroid [283,284] and morphine [285]. Also MS 209, a quinoline derivative exhibiting multidrug resistance in cancer therapy was directly glucuronidated based on
an O-pivaloyl-protected donor [286]. 5-Hydroxypyridine derivative 42b ( > Scheme 42) which
is part of ABT-724, a potent D4 dopamine receptor agonist, could be directly glucuronidated [287] leading to 42c. Further transformations via intermediates 42e and 42f gave the desired
glycosylated metabolite 42g.
3.2
511
⊡ Scheme 41
⊡ Scheme 42
synthesis the hydroxymethyl group is selectively oxidized to the carboxylate group. Excellent results in direct glucuronidation based on O-isobutyryl-protected trichloroacetimidate
have been obtained by Scheinmann and Stachulski et al., who glucuronidated for instance
an anti-estrogenic steroid [283,284] and morphine [285]. Also MS 209, a quinoline derivative exhibiting multidrug resistance in cancer therapy was directly glucuronidated based on
an O-pivaloyl-protected donor [286]. 5-Hydroxypyridine derivative 42b ( > Scheme 42) which
is part of ABT-724, a potent D4 dopamine receptor agonist, could be directly glucuronidated [287] leading to 42c. Further transformations via intermediates 42e and 42f gave the desired
glycosylated metabolite 42g.