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Erythritol derivatives

Coxon and Stoddart have directed their attention to the formation of penta-erythritol-derived cryptands. With these molecules, the strategy was to block one pair of hydroxyl groups as an acetal and form a crown from the remaining diol. In the first of the two reports cited above, this was accomplished by treating the 0-benzylidine derivative of pentaerythritol with base and diethylene glycol ditosylate. The crown was then treated with a mixture of UAIH4 and BF3 which gives partial reduction of the acetal as shown in (8.9), above. The monoprotected diol could now be treated in a fashion similar to that previously described and the benzyloxy cryptand (77) would result. The scheme is illustrated below as Eq. (8.10). [Pg.353]

Chiral alkoxy allenes derived from 1,3-alkylidene-L-erythritol and -D-threitol have been used in cycloaddition reactions to provide the 4-substituted /3-lactams 418 (R = Me, Ph). Intramolecular alkylation at nitrogen was achieved by the action of potassium carbonate and tetrabutylammonium bromide in dry acetonitrile. The absolute stereochemistry of the product 419 (R = Me, Ph) was assigned on the basis of the CD helicity rule (see Section 2.04.3.5) and NMR spectroscopy. The [2+2] cycloaddition of CSI to threitol vinyl ethers was found to have low stereoselectivity in contrast to the findings with erythritol derivatives <2004CH414, 2005EJ0429>. [Pg.296]

This methodology has been used for the preparation of L-threitol (4) (Scheme 9.9) and erythritol derivatives.93 This simple iterative process has been used for the simple alditols,93 94 deoxyalditols,95 and aldoses93 and for all of the L-hexoses.96,97... [Pg.128]

The D-erythritol derivative 26, obtained from L-tartaric acid, was reduced to provide the... [Pg.391]

Figure 2.24 Synthesis of polyamide from erythritol-derived diamine and dicarboxylic acid dichloride. Figure 2.24 Synthesis of polyamide from erythritol-derived diamine and dicarboxylic acid dichloride.
Erythritol-derived diol 8 was acetylated with vinyl acetate and lipase AK (Amano) to give (2S,3R)-9 (Figure 24.5) [8]. This half-acetate 9 was converted to (+)-endo-brevicomin, a male-produced component of the southern pine beetle pheromone. [Pg.588]

More recently Frechet and Gitsov [130] used a similar approach as above and synthesized a novel series of dendritic copolymers derived from a central penta-erythritol core unit. These hybrid star molecules behaved as unimolecular micelles with different core-shell conformational-structures as a response to the polarity of the solvent used. [Pg.57]

Most poly(HA) depolymerases are inhibited by reducing agents, e.g., dithio-erythritol (DTT), which indicates the presence of essential disulfide bonds, and by serine hydrolase inhibitors such as diisopropyl-fluoryl phosphate (DFP) or acylsulfonyl derivates. The latter compounds covalently bind to the active site serine of serine hydrolases and irreversibly inhibit enzyme activity [48]. [Pg.293]

KUZUYAMA, T., TAKAGI, M., KANEDA, K, WATANABE, H, DAIRI, T., SETO, H., Studies on the nonmevalonate pathway conversion of 4-(cytidine 5 -diphospho)-2-C-methyl-D-erythritol to its 2-phospho derivative by 4-(cytidine 5 -diphospho)-2-C-methyl-D-erythritol kinase, Tetrahedron Lett., 2000, 41, 2925-2928. [Pg.162]

Fig. 2 Two possible biosynthetic pathways to pyrethrolone. The [l-13C]D-glucose-derived 13C labels that occur in the mevalonic acid and 2-C-methyl-D-erythritol 4-phosphate (13) pathways are colored in red and green, respectively. The phosphate moiety is indicated as P ... Fig. 2 Two possible biosynthetic pathways to pyrethrolone. The [l-13C]D-glucose-derived 13C labels that occur in the mevalonic acid and 2-C-methyl-D-erythritol 4-phosphate (13) pathways are colored in red and green, respectively. The phosphate moiety is indicated as P ...
In addition to these physical studies at the Bureau, Tipson was able to return to his synthetic interests, both alone and in collaboration with other staff members. He was especially pleased to prepare D-talose in crystalline form, an accomplishment that had eluded Emil Fischer. Pursuing his longstanding interest in the reaction of sulfonic esters with iodide and following an earlier observation that the tetratosyl ester of erythritol is converted into butadiene by the action of sodium iodide and zinc, he demonstrated (with A. Cohen) that nonterminal unsaturation may be conveniently introduced into alditol derivatives by reaction of contiguous secondary sulfonates with sodium iodide and zinc dust in boiling A.A-dimethylformamide. This Tipson-Cohen reaction subsequently proved of great utility in other hands for the conversion of more complex carbohydrate structures into vicinal dideoxy derivatives. [Pg.425]


See other pages where Erythritol derivatives is mentioned: [Pg.575]    [Pg.48]    [Pg.575]    [Pg.78]    [Pg.247]    [Pg.949]    [Pg.921]    [Pg.175]    [Pg.5]    [Pg.178]    [Pg.228]    [Pg.575]    [Pg.48]    [Pg.575]    [Pg.78]    [Pg.247]    [Pg.949]    [Pg.921]    [Pg.175]    [Pg.5]    [Pg.178]    [Pg.228]    [Pg.52]    [Pg.344]    [Pg.819]    [Pg.357]    [Pg.99]    [Pg.306]    [Pg.154]    [Pg.54]    [Pg.237]    [Pg.245]    [Pg.171]    [Pg.221]    [Pg.360]    [Pg.159]    [Pg.173]    [Pg.150]    [Pg.7]    [Pg.45]    [Pg.93]    [Pg.94]    [Pg.94]    [Pg.95]    [Pg.96]    [Pg.97]    [Pg.580]    [Pg.548]   
See also in sourсe #XX -- [ Pg.231 ]




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Erythritols

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