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Conjugate addition of lithium methylcyanocuprate to the titlealdehydes proceeded with high diastereoselectivity (d.e. 94%). Methyl lithium 1,2-addition, followed by Swern oxidation of the resultingalcohols, gave benzyl botryodiplodin and benzyl epi-botryodiplodin.Hydrogenolysis of the benzyl groups gave the enantiomeric pairs ofbotryodiplodin 10r and 10s and epi-botryodiplodin (9r and 9s).

1,2-Addition of 3,4-methylenedioxymagnesium bromide to 2-(R) and (S)-benzyloxy-2,5-dihydro-4-furancarboxaldehyde, followed by oxidation, gave the title ketones (3r and 3s). Conjugate addition of the anions of 3,4,5-trimethoxy- and 3,4-methylenedioxybenzaldehyde diphenylthioacetal to 3r and 3s and Raney-nickel desulfurisation, followed by hydrogenolysis under various conditions, gave the title lign

The chiral aldehydes (-)-(2S,5S)- and (-)-(2S,5R)-2-[[[dimethyl( 1,1,2-trimethylpropyl)silyl]oxy]methyl]-5-methoxy-2,5-dihydrofuran-3-carbaldehyde (2 and 4) were synthesized in 60 and 15% yield, respectively, by lithium bromide induced rearrangement of 6-O-silylated methyl 2,3- and 3,4-anhydro-a- and -d-D-hexopyranosides, obtained in two steps from methyl α- and β-D-glucopyranoside. Rearrangement

The title aldehydes (lr, 1s, 2, and 3) underwent virtually diastereospecific conjugate addition by lithium methylcyanocuprate. The bulkiness of the anomeric benzyloxy or methoxy groups direct the attacking nucleophile to the less hindered side of the furanosidic ring. The stereochemical outcome of the Diels-Alder additions of cyclopentadiene to lr and 1s was governed almost completely by the bulki

Baker's yeast phosphatases induced regioselective hydrolysis on phytic acid leading to D-myo-inositol 1,2,6-tris(phosphate) which was transformed in optically active (+)-D-3,4,5-tri-O-phenylcarbamoyl-myo-inositol.

4-Deoxy-4-fluoro-myo-inositol was prepared by means of DAST with retention of configuration due to the assistance of a neighbouring benzyl ether.

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Phosphorylation of 6-O-tritylated methyl α-D-mannopyranosidc followed by deprotection gives an analogue of α-trinositol having virtually similar orientation of the phosphate groups. Biological testing showed the analogue to be inferior with respect to pharmacological effects.

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Periodate oxidation of 1D-myo-inositol 1,2,6-trisphosphate pentasodium salt (α-trinositol) gives the expected cyclic D-arabino-pentodialdose as a mixture of anomers. Reaction with a primary amine and subsequent reduction with sodium borohydride gives the title compounds.

The acylation of α-trinositol is very sensitive to reaction conditions. Competing condensation reactions may give pyrophosphates and cyclic phosphates. Treatment of a tert-ammonium salt corresponding to α-trinositol with carboxylic acid anhydride and DMAP gives a good yield of the expected esters.

Acyloxymethylation of an acylated silver salt of α-trinositol gives, after deprotection, membrane permeable 1D-myo-inositol 1,2,6-tris(ethoxycarbonyloxymethyl sodium phosphate). The acyl groups, 3-(4,5-methylenedioxy-2-nitrophenyl)propanoyl, are cleaved by hydrogenolysis.

Acylation of 1D-myo-inositol 1,2,6-trisphosphate (α-trinositol) followed by alkylation of the phosphate groups with benzyl bromoacetate or 2-benzyloxyethyl iodide and deprotection provides a route to analogues with modified phosphate groups. The modifications made alter steric and ionisation properties but the possibility to participate in hydrogen bonding and ionic interaction is retained.

Phytic acid treated with Baker's yeast gave D-myo-inositol-1,2,6-tris(phosphate) (α-trinositol) which was transformed into (+)-D-1,2-O-isopropylidene-myo-inositol and (-)-D-4,5-tri- O-benzyl-myo-inositol, two key intermediates in the synthesis of optically active myo-inositol derivatives and related compounds.

The reaction of perbenzylated (±)-myo-inositol 1,2-bis- and 1,2,6-tris-phosphites with benzyl bromoacetate, followed by catalytic (Pd/C) hydrogenolysis affords (±)-myo-inositol 1,2-bis- and 1,2,6-tris(carboxymethylphosphonate). The same procedure is used for the synthesis methyl α-D-mannopyranoside 2,3,4-tris(carboxymethylphosphonate).

α-Trinositol analogues, including methyl ethers, deoxy, oxa and aza derivatives were prepared. The parent compound possesses weak analgesic and anti-inflammatory properties. Removal of the non-phosphorylated hydroxyls generates a compound devoid of analgesic activity but which retains the anti-inflammatory property of the parent compound. The protection of these hydroxyls as methyl ethers lends to

D-(-)-Quinic acid was appropriately protected to permit the phosphorylation of the three vicinal hydroxyl groups. Final deprotection lead to tris(phosphates) possessing the same configuration as the parent α-trinositol and an arm suitable for the attachement of a photoactivable group.