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Anhydrides reduction with NaBH

Anthracene is noncarcinogenic and is structurally incapable of forming a bay region diol epoxide. Anthracene 1,2-dihydrodiol is most conveniently synthesized from 2-anthranol by oxidation with phenylseleninic anhydride to anthracene 1,2-dione (55) followed by reduction with NaBH in ethanol (22) or LiAlH (55). Anthracene 1,2-dihydrodiol has also been synthesized via the Prdvost reaction route... [Pg.51]

Polonoeski reaction (2, 7 5, 3). The first synthesis of the dimeric indole alkaloid vinblastine (4), used in the treatment of lymphomas, involved coupling of two indole units using a Polonovski reaction. Thus reaction of the N-oxide (1) and vindoline (2) with trichloroacetic anhydride afforded the quaternary im-monium compound (3), which was converted into (4) by standard methods (reduction with NaBH, rcacclylalion). ... [Pg.194]

The reaction has been considerably improved by several modifications. The initial condensation is accelerated by use of KF and 18-crown-6 isopropanol is a suitable solvent. Acetylation is effected with acetic anhydride at 25° with 4-dimethylamino-pyridine as catalyst (3, 118). The reduction is carried out with NaBH in ethanol. These mild conditions are compatible with various functional groups often present in the synthesis of natural products. ... [Pg.468]

A trisaccharide isolated from milk was completely hydrolyzed by /3-galactosidase to galactose and glucose in a 2 1 ratio. Reduction of the original trisaccharide with NaBH<, followed by exhaustive methylation, acid hydrolysis, then another NaBH< reduction step, and finally acetylation with acetic anhydride yielded three products (a) 2,3,4,6-tetramethyl-1,5-diacetyl-galactitol, (b) 2,3,4-trimethyl-l,5,6-triacetylgalactitol, and (c) 1,2,3,5,6-... [Pg.127]


See other pages where Anhydrides reduction with NaBH is mentioned: [Pg.283]    [Pg.56]    [Pg.182]    [Pg.264]    [Pg.93]    [Pg.47]    [Pg.29]   
See also in sourсe #XX -- [ Pg.4 , Pg.327 ]




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NaBH

With anhydrides

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