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Preparation of Oxysterols by C-H Oxidation of Dibromocholestane with Ru(Bpga) Catalyst.

ABSTRACT: Seven mono- and dihydroxycholesterols were prepared by direct C-H oxidation of the cholestane skeleton with a recently developed Ru(Bpga) catalyst (Ru(Bpga) = [RuCl (bpga) (PPh3)] Cl; bpga = 2-(bis(pyridin-2-ylmethyl)amino)-N-(2,6-dimethylphenyl)acetamide)). Due to the high selectivity of the Ru(Bpga) complex for tertiary C-H, the reaction afforded a mixture of 25-, 20-, 17-, and 14-oxygenated cholesterols that could be easily separated by high-performance liquid chromatography. These results suggest that late-stage C-H oxidation could be a viable strategy for preparing candidate metabolites of biologically important molecules.

SUBMITTER: Fujii Y

PROVIDER: S-EPMC8746986 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Preparation of Oxysterols by C-H Oxidation of Dibromocholestane with Ru(Bpga) Catalyst.

Fujii Yui Y Yoritate Makoto M Makino Kana K Igawa Kazunobu K Takeda Daiki D Doiuchi Daiki D Tomooka Katsuhiko K Uchida Tatsuya T Hirai Go G

Molecules (Basel, Switzerland) 20211230 1

Seven mono- and dihydroxycholesterols were prepared by direct C-H oxidation of the cholestane skeleton with a recently developed Ru(Bpga) catalyst (Ru(Bpga) = [RuCl (bpga) (PPh<sub>3</sub>)] Cl; bpga = 2-(bis(pyridin-2-ylmethyl)amino)-<i>N</i>-(2,6-dimethylphenyl)acetamide)). Due to the high selectivity of the Ru(Bpga) complex for tertiary C-H, the reaction afforded a mixture of 25-, 20-, 17-, and 14-oxygenated cholesterols that could be easily separated by high-performance liquid chromatography ...[more]

PMID: 35011456

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