Stereoselective synthesis of N-benzyl conduramine F-1, N-benzyl ent-conduramine E-1, dihydroconduramine F-1 and ent-dihydroconduramine E-1

A short and stereoselective synthesis of conduramine F-1 and ent-conduramine E-1 derivatives have been achieved starting from d-mannitol using nucleophilic vinylation on imine. A concise sequence of vinylation at both ends of d-mannitol and followed by RCM allowed us to prepare target compound.     

The oxidation of organic substances by compounds of tervalent manganese-I Oxidation of mandelic acid, ethylene glycol, glycerol and d-mannitol by the pyrophosphate complex of manganese(III) and by manganese(III) sulphate

The oxidation of mandelic acid, ethylene glycol, glycerol and d-mannitol by the pyrophosphate complex of manganese(III) and with manganese(III) sulphate was studied. It was shown that benzaldehyde is formed by oxidation of mandelic acid, which undergoes no further oxidation. In the case of ethylene glycol, glycerol and d-mannitol the reactions do not follow a simple course and therefore are not of analytical utility. The effect of acidity and time on the course of the reactions was found and a procedure for the indirect titrimetric determination of mandelic acid with both reagents proposed.     

Synthesis of furan derivatives of cyclic β-amino acid cispentacin via intramolecular nitrile oxide cycloaddition

Two furan derivatives of cispentacin have been synthesized starting from a d-mannitol derived conjugated nitroolefin through intramolecular nitrile oxide cycloaddition (INOC) as a key step.     

Olefin cross-metathesis based approach for the stereoselective total synthesis of (+)-cardiobutanolide

Olefin cross-metathesis approach to (+)-cardiobutanolide has been achieved starting from d-mannitol utilizing Sharpless kinetic resolution and Sharpless asymmetric dihydroxylation.     

Chiron approach for the formal synthesis of (+)-syributin 1

A chiron approach for the formal synthesis of (+)-syributin 1 from d-mannitol has been described. The key steps are a Wittig reaction and RCM.     

Synthesis of diastereoisomeric pairs of novel analogues of d4T having an isochroman glycon moiety; their enzymatic kinetic resolution, their enantiopure synthesis, molecular modeling and NMR structural study

An efficient route, starting from 2-bromobenzaldehyde, is described to synthesize racemic diastereoisomeric thymine derivatives of isochroman, which are aromatic analogues of Stavudine, an approved anti-HIV drug. The relative configurations were determined by NOE proton NMR experiments in connection with molecular modeling. Following the separation of the latter diastereoisomers, kinetic resolution was achieved via a transesterification reaction catalyzed by lipases. Using this method, moderate ee's were obtained (0.74-0.98). Thus, an alternative strategy starting from d-mannitol was proposed to provide pure enantiomers. The attribution of absolute configurations was made by chemical filiation on the basis of the configurations obtained from d-mannitol. The structural attributions were confirmed by studying the behavior of proton NMR shifts of the corresponding isochroman Mosher's esters.     

Interactions in aqueous nonelectrolyte systems. Gibbs energy of interaction of the ether group with the hydroxyl group and the amide group

Freezing temperatures of dilute aqueous solutions of equimolar mixtures of 1,3,5-trioxane with myo-inositol, d-mannitol, cyclohexanol, formamide, and acetamide, and 1,4-dioxane with myo-inositol, d-mannitol, formamide, and acetamide have been measured. These data yield pairwise Gibbs energies of interactions between the molecules in an aqueous solution. Using the group additivity principle, the results also yield the pairwise functional group Gibbs energies of interaction for the ether group with the hydroxyl and amide group. These results have been combined with all available data from the literature to yield the Gibbs energy and enthalpy of interaction of amides, ethers, alcohols, and saccharides in aqueous solution.To whom correspondence should be addressed.     

Formal synthesis of dysiherbaine

A formal synthesis of dysiherbaine was achieved from d-mannitol using Grignard addition on chiral imine, RCM and Michael addition as key steps.     

Stereoselective syntheses of enantiomerically pure 2,5-disubstituted dihydropyrans based on olefin metathesis

A short synthesis of 2,5-disubstituted dihydropyrans starting from d-mannitol as a chiral building block is described. Our synthetic approach combines ruthenium-catalyzed ring closing olefin metathesis and palladium-catalyzed nucleophilic substitution.     

Convergent total synthesis of squamostolide

A convergent total synthesis of the Annonaceous acetogenin squamostolide, in a longest linear sequence of nine steps from d-mannitol, is reported. Central to the efficiency of the synthesis is a highly selective tandem ring-closing/cross metathesis step in which lactone formation and fragment coupling are accomplished.     

Stereoselective total synthesis of cytotoxic sporiolide A

A simple and highly efficient stereoselective total synthesis of cytotoxic agent sporiolide A has been achieved starting from d-mannitol; the strategy of synthesis utilizes stereoselective zinc-mediated allylation, aldol coupling and ring-closing metathesis as key steps.     

Synthesis and applications of chiral bis-THF in asymmetric synthesis

The synthesis of enantiopure bis-THF is described, starting from d-mannitol. Bis-THF is used as chiral ligand for organolithium reagents in four different reactions. The enantioselectivity provided by this ligand is moderate, and the asymmetric induction is in line with the expected model.     

Enantioselective addition of diethylzinc to aldehydes catalyzed by a new chiral β-amino alcohol derived from d-mannitol

A new chiral β-dialkylamino alcohol 1 prepared from d-mannitol has been used as a highly effective chiral catalyst for the enantioselective addition of diethylzinc to unhindered aliphatic aldehydes to afford the product alcohols in up to 94% ee.     

Stereoselective synthesis of (+)-secosyrin 1

A Chiron approach for the synthesis of (+)-secosyrin 1 from d-mannitol has been described. The key steps are a stereoselective Wittig reaction and an intramolecular Michael addition on the disubstituted butenolide, leading to a highly stereoselective formation of the tertiary chiral centre of (+)-secosyrin 1.     

Synthesis and glycosidase inhibitory activity of pseudo-di-(or tri-)saccharides

The synthesis of pseudo-di-(or tri-)saccharides with a d-mannoazepane or a l-gulopiperidine skeleton either N-linked to a d-gluco-C-furanoside or to d-mannitol, and evaluation of their inhibitory activities against α- or β-d-glucosidase, α-d-mannosidase and α-l-fucosidase are described.     

Synthesis of chiral 1,3-calix[4](crown-6) ethers as potential mediators for asymmetric recognition processes

Novel chromogenic 1,3-calix[4](crown-6) derivatives comprised of 1,1′-binaphthyl-, methyl-α-d-glucoside-and d-mannitol moieties in the crown ether ring have been synthesized. UV–vis spectroscopic measurements of the 2,4-dinitrophenylazo chromogenic molecules indicated noticeable chiral discrimination associated with coloration towards primary amine enantiomers.     

Synthesis of (R)-quinuclidine-2-carboxylic acid in enantiomerically pure form

Enantiomerically pure (R)-quinuclidine-2-carboxylic acid has been prepared by following two related 7 step synthetic routes in 16% and 19% overall yield, respectively, from a 1,2,4-trisubstituted piperidine that is easily prepared from inexpensive d-mannitol.     

A facile and stereoselective synthesis of the C-2 epimer of (+)-deacetylanisomycin

A short, simple and efficient synthesis of the C-2 epimer of (+)-deacetylanisomycin starting from d-mannitol, utilizing an epoxide opening with a Grignard reagent and acid catalysed unusual intramolecular 5-endo-tet cyclization as key steps has been reported.     

6,6′-Bis-substituted BINOL boronic acids as enantioselective and chemoselective fluorescent chemosensors for d-sorbitol

A new chiral fluorescent BINOL boronic acid 1 has been synthesized. The chiral recognition properties of 1 are drastically different from BINOL boronic acid c. Sensor 1 shows improved enantioselectivity as well as chemoselectivity toward sugar alcohols, such as d-sorbitol and d-mannitol.The enantioselectivity of sensor 1 toward d-sorbitol (K_R/K_S) is 1:35 (pH 9.0), and the chemoselectivity for d-sorbitol/d-mannitol is 20:1.     

Total synthesis and structural confirmation of the marine natural product Dysinosin A: a novel inhibitor of thrombin and Factor VIIa

The structure and absolute configuration of the marine antithrombotic product dysinosin A was confirmed by total synthesis. The strategy involved disconnections to three subunits, of which two were synthesized from the readily available l-glutamic acid, d-leucine, and d-mannitol. The Grubbs olefin metathesis carbocyclization reaction was utilized to prepare two intermediates.