Monosaccharide natural products

Pyran derivatives, useful intermediates in the total synthesis of many monosaccharides and other natural products, have been synthesized by hetero-Dish-Alder reaction by using carbonyl compounds as dienophiles [9, 23]. 

P. M. Collins and R. J. Ferrier, Monosaccharides Their Chemistry and Their Role in Natural Products, John Wiley Sons, New York, 1995, p. 115. 

Aldonolactones are useful starting materials for the synthesis of modified sugars. They have also been used as chiral templates in synthesis of natural products. Some of them are inexpensive, commercially available products or they may be obtained readily from the respective monosaccharides. The purpose of this chapter is to survey the main reactions of aldonolactones. Previous reviews on the subject include articles on gulono-1,4-lactones (1) and D-ribonolactone (2). Methods of synthesis, conformational analysis, and biological properties are not discussed in this chapter. 

The hetero-Diels-Alder cyclization reaction of tra s-l-methoxy-3-trimethylsilyloxy-1,3-butadiene (Si) (= Danishefsky s diene) with benzaldehyde (S ) (Scheme 12.23) [217-221] is a promising reaction for evaluating the catalytic properties of Lewis acidic lanthanide centers, and has enormous potential for asymmetric synthesis of natural products (e.g., monosaccharides) [222-225]. 

Our strategy for synthesis of the oligosaccharide chains,27.28 calls for 2,6-dideoxyhexoses or the corresponding glycals to serve as precursors for both a- and p-glycosidation reactions. It a selective p-glycosidation protocol can be developed, then in principle any structural isomer or analogue of the natural product can be assembled from a common set of monosaccharide precursors.29... 

The example of a total extract composition of a tropical soil from the Amazon, Brazil, shows mycose as the major compound, numerous other monosaccharides, lipid components such as fatty acids and fatty alcohols, and natural product biomarkers (Fig. 9a). The mycose and elevated levels of the other saccharides reflect the efficient fungal/microbial degradation of plant detritus in the tropics. This can be compared to the saccharides in the soil from an almond orchard in California, where glucose and mycose are the main sugars with lipids, sterols and triterpenoids (Fig. 9b, ). 

Collins PM, Ferrier RJ (1995) Oxidations monosaccharides their chemistry and their role in natural products. Wiley, New York... 

The chiral synthesis,219-221 by the use of monosaccharides, of optically active natural products having mainly branches of the B-type has now become common in organic chemistry. The reduction of alkylidene derivatives was actually used for the synthesis of thromboxane B2,222 cana-densolide,223 and a degradation product from boromycin.224... 

For reviews see (a) R. J. Fenier and S. Middleton, The conversion of carbohydrates into functionalized cyclopentanes and cyclohexanes, Chem. Rev. 95 2779 (1993) (b) K. J. Hale, Monosaccharides Use in asymmetric synthesis of natural products, Rodd s Chemistry of Carbon Compounds. Second Supplement to the 2nd ed. (M. Sainsbury, ed.), Elsevier, Amsterdam, 1993, Vol. 1E/F/G, pp. 315-435 (c) T. D. Inch, Formation of convenient chiral intermediates from carbohydrates and their use in synthesis, Tetrahedron 40 3161 (1984) (d) S. Hanessian, Total Synthesis of Natural Products The Chiron Approach Pergamon, New York, 1983. 

K. J. Hale, Monosaccharides Use in the asymmetric synthesis of natural products, Rodd s Chemistry of Carbon Compounds, 2nd ed., Vol. 1 EFG Second Suppl. (M. Sainsbury, ed.), Elsevier Science Publishers, Amsterdam, 1993, p. 315, and references therein. 

Collins, P.M. and Ferrier, R.J. (1995) Monosaccharides Their Chemistry and Their Roles in Natural Products. Wiley-Interscience, New York. 

Fructose 1,6-biphosphate aldolase from rabbit muscle in nature reversibly catalyzes the addition of dihydroxyacetone phosphate (DHAP) to D-glyceraldehyde 3-phosphate. The tolerance of this DHAP-dependent enzyme towards various aldehyde acceptors made it a versatile tool in the synthesis of monosaccharides and sugar analogs [188], but also of alkaloids [189] and other natural products. For example, the enzyme-mediated aldol reaction of DHAP and an aldehyde is a key step in the total synthesis of the microbial elicitor (—)-syringolide 2 (Fig. 35a) [190]. 

Part B discusses enantioselective natural product synthesis from monosaccharides. Nowadays, most natural product syntheses are performed in an asymmetric manner. This development is due principally to the realisation... 

In Part B, we analyse and discuss some recent enantiospecific natural product syntheses that have utilised monosaccharides as chiral starting materials. The coverage is not meant to be exhaustive or extensive but, rather, illustrative of the way in which monosaccharides are currently being used in asymmetric natural product synthesis. For more exhaustive coverage of this field, the reader is referred to several fine monographs and reviews.18... 

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