Erythritol, synthesis

NMR, 4, 575 Erythritol, 1,4-anhydro-structure, 4, 546 Erythromycin antibacterial veterinary use, 1, 206 as pharmaceutical, 1, 153 synthesis, 1, 480 Erythropterin biosynthesis, 3, 321 occurence, 3, 323 structure, 3, 276 synthesis, 3, 289 Erythropterin, 3,5-dimethyl-methyl ester synthesis, 3, 303 Erythrosine application, 3, 879 Esculetin... 

We have noted above (Sect. 8.3) that certain substituted benzoic acids have been used in the synthesis of endolipophilic cryptands but it is the glycerol and penta-erythritol units which have been used most commonly in this application. These are discussed separately, below. 

Erlenmeyer synthesis org chem Preparation of cyclic ethers by the condensation of an aldehyde with an a-acylamino acid in the presence of acetic anhydride and sodium acetate. 3r-l3n,mT-3r sin-th3-s3s erucic acid org chem C22H42O2 A monoethenoid acid that is the cis isomer of bras-sidic acid and makes up 40 to 50% of the total fatty acid in rapeseed, wallflower seed, and mustard seed crystallizes as needles from alcohol solution, insoluble in water, soluble in ethanol and methanol. o rus ik as ad erythrite See erythritol. er o.thrTt ... 

In a series of papers, Kent and coworkers reported on the synthesis of the racemic 2-fluorotetritols and 2-fluoropentitols, and related carbohydrates from simple, non-carbohydrate precursors containing a fluorine atom in the carbon chain. Thus, synthesis of 2-deoxy-2-fluoro-DL-erythritol (537) and its threo isomer (538) was accomplished303 by vigorous reduction of ethyl ethoxalylfluoroacetate (536) with lithium... 

Wide practical application of erythritol tetranitrate has been prevented by the lack of readily available raw material. The main sources of erythritol are certain kinds of moss and sea-weeds, though chemical synthesis from acetylene, according to the following scheme, has been suggested by Reppe [2] ... 

One of the more exciting and recent advances in the field of plant biochemistry has been the discovery of the mevalonate-independent pathway for the biosynthesis of isoprenoids (Fig. 10.4). This new pathway, referred to a the methyl-erythritol-phosphate or MEP pathway for the first intermediate committed solely to the biosynthesis of isoprenoids, was first discovered in prokaryotes capable of accumulating hopenes, the equivalent of eukaryotic sterols. 6,17 The MEP pathway has since been confirmed in plants and, not surprisingly, has been localized to chloroplasts.18 Operation of the MEP pathway is intimately related to the reactions of CO2 fixation and photosynthesis, as evidenced by the two immediate precursors pyruvate and phosphoglyceraldehyde for this pathway. Two important features of this pathway are that mevalonate is not an intermediate in the plastidic synthesis of isopentenyl (IPP) and dimethylallyl diphosphate, (DMAPP), and this pathway... 

Standard synthetic methods are used to couple partially protected penta-erythritol to the core cell and subsequent dendrimer surfaces [82, 133]. Synthesis of the first generation involves displacement of bromide from C(CH2Br)4 with a masked pentaerythritol (bicyclic orthoester). One obtains three hydroxyl groups per terminal group after deprotection (Scheme 24). Therefore, a series that triples both its surface hydroxyl groups and its molar mass is obtained (see Table 5). 

Scheme 4.331 provides a further illustration of the power of enzymatic methods for the selective synthesis of either member of an enantiomeric pair on a preparative scale.621-622 Pseudomonas cepacia lipase (PCL) hydrolysed the meso-diacetate 331.1 to give (25,3/ )-2 3-0-cyclohexylidene-erythritol monoacetate (331 4) in 91% chemical yield and >99% ee whereas transesterification using vinyl acetate accomplished the conversion of the diol 3313 to the (2/ ,35)-antipode 331.4 in diminished yield (78%) but comparable ee. Vinyl or propenyl acetate ensures a favourable equilibrium owing to tautomerisation of the enol generated during the transesterification.623 624... 

For an early example of photochemical asymmetric synthesis in irradiation of L-erythritol 1,4-dicinnamate derivatives see B. S. Green, A. T. Hagler, Y. Rabinsohn and M. RejtO, Isr. J. Chem., 916ITI, 15, 124. 

Erythritol 1 is a tetraol with a central eryf/rro-conflgured diol group. In combination with the terminal hydroxyl functions there are several conformations to act as a chelate ligand. In most of its characterized solid-state stmctures, erythritol is coordinated to two central atoms by acting as a bis-l,2-diolato ligand, at which the deprotonation of the hydroxyl groups is a consequence of the synthesis from alkaline solutions and/or complexation of more or less Lewis acidic central atoms. A complex of this type is obtained upon the reaction of erythritol with two equivalents of [(NH3)2Pd(OH)2] in aqueous solution which leads to the centrosymmetric structure of 9 (O Fig. 1) [18],... 

Optically active C4-building blocks of type 1 are versatile starting compounds in organic synthesis. Important members of this class, among numerous others, are derivatives of threose8-9 and erythrose, respectively, such as 2,4-O-ethylidene-D erythrose 2, the corresponding "Horner enoate" 3, or the erythritol 4. 

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