Synthetic monosaccharide

The above example demonstrates the potentialities of mass spectrometry as a method for elucidating the position of isopropylidene groupings. This problem has often to be solved in synthetic monosaccharide chemistry, especially when the compound may form several isomeric isopropylidene derivatives and the chemical methods are tedious and, sometimes, unreliable. 

Biopolymers are the naturally occurring macromolecular materials that are the components of all living systems. There are three principal categories of biopolymers, each of which is the topic of a separate article in the Eniyclopedia proteins (qv) nucleic acids (qv) and polysaccharides (see Carbohydrates Microbial polysaccharides). Biopolymers are formed through condensation of monomeric units ie, the corresponding monomers are amino acids (qv), nucleotides, and monosaccharides, for proteins, nucleic acids, and polysaccharides, respectively. The term biopolymers is also used to describe synthetic polymers prepared from the same or similar monomer units as are the natural molecules. 

Traditionally, the glycosidases used for synthetic purposes are exoglyco-sidases, which transfer only the non-reducing terminal monosaccharide unit... 

In connection with the synthetic work directed towards the total synthesis of polyene macrolide antibiotics -such as amphotericin B (i)- Sharpless and Masamune [1] on one hand, and Nicolaou and Uenishi on the other [2], have developed alternative methods for the enantioselective synthesis of 1,3-diols and, in general, 1, 3, 5...(2n + 1) polyols. One of these methods is based on the Sharpless asymmetric epoxidation of allylic alcohols [3] and regioselective reductive ring opening of epoxides by metal hydrides, such as Red-Al and DIBAL. The second method uses available monosaccharides from the "chiral pool" [4], such as D-glucose. 

Tables V-LVII detail H and F shift and coupling information, and Tables LVIII to LXXI incorporate the C-n.m.r. data. The data within this compilation are arranged according to the following outline hexoses prior to pentoses, followed by anhydro sugars, sugar acids and lactones, amino sugars (and their synthetic, A -containing precursors), mono-, di-, and tri-deoxy sugars, branched derivatives, ketoses, polyfluorinated monosaccharides, and, finally, difluorinated amino sugars. Within this compilation, and even within each table, pyranoid derivatives are listed prior to their furanoid counterparts, hexoses prior to pentoses, functionalized prior to deoxy compounds the arrangement within each sub-table is made alphabetically.

Besides stereoselective synthesis of various monosaccharides, stereoselective reaction for the preparation of glycosides is an important problem in the synthetic field of carbohydrate chemistry. However, the classical methods, which require the assistance of heavy metal salts or drastic reaction conditions, are still employed by and large in the synthesis of such compounds. Taking these disadvantages into consideration, new glycosylation reactions, which proceed under mild reaction conditions with high selectivity, have been developed and exploited. 

For the preparation of optically active polyhydroxy compounds, such as synthetic intermediates of monosaccharides, the asymmetric aldol reaction of 1,3-dimethoxy-2-propane (Table 3) by... 

As shown in chapter, Synthetic polymers from readily available monosaccharides by J, A, Galbis and M,G, Garcia-Martin, aldonolactones are useful monomeric materials for the synthesis of biodegradable polymers and bio-compatible polymers for medicinal applications. 

Aldonolactones serve as suitable monomers for the generation of homo- and copolymers, especially through ring-opening polymerization (ROP). Among them are the carbohydrate-analogs of s-caprolactone, i.e., aldono-1,6-lactones. The first example of such derivatives and further ROP was reported by Galbis and co-workers [61], see also chapter, Synthetic polymers from readily available monosaccharides ... 

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