Arabinose 1-phosphate preparation

Kdo was prepared on the 38-mmol scale starting from D-arabinose, by the simultaneous operation of three enzymes in the same vessel. One is Kdo synthetase 56 hexokinase catalyzes the phosphorylation57 of D-arabinose by ATP (catalytic), and pyruvate kinase catalyzes58 the regeneration of ATP with enolpyruvate phosphate. Such systems are described in more detail in Section IV. In this preparation, enolpyruvate phosphate serves two very different purposes, acting as a source of high-energy phosphate, and as a three-carbon donor.59... 

Occurrence and preparation. The tetrose (4) participates as D-erythrose 4-phosphate in the pentose phosphate pathway of carbohydrate metabolism.11 D-Erythrose can be prepared using a method of degradation from the pentose, D-arabinose,19 or from D-glucose.20 Synthesis of the 4-phosphate has been reported.21... 

Arabinose-1-phosphate (ara-l-P) has already been isolated as barium salt from the reaction mixture, and the mechanism of trans-arabinosylation has also been investigated. It has been clarified that nucleoside phosphorylases are involved in the trans-arabinosylation reaction, and ara-l-P is the reaction intermediate for arabinoside preparation. ... 

Syringolide 2 (58), a bacterial signal molecule that elicits active defence in resistant plants, has been made (Scheme 11) from the protected ketose 57, itself prepared from D-arabinose (sugar carbons numbered) in nine steps. This sequence can be considerably shortened by use of a chemo-enzymatic approach, in which 57 was made in three steps by condensation of dihydroxyacetone phosphate with 0-Pmb-glycolaldehyde, catalysed by fructose 1,6-diphosphate aldolase, followed by action of phosphatase and formation of the isopropylidene derivative. ... 

Simple chemical syntheses of GDP-fucose (1) and its analogs 2 and 3 were devised which involved the direct reaction of a-pyranosyl bromides with tetrabutylammonium dibenzylphosphate (Figure 2) (22), These displacement reactions were carried out with protected derivatives of the parent L-fucose, 3-deoxy-L-fucose and D-arabinose (the 6-demethyl analog of L-fucos because of the relative ease of preparation of the required glycosyl bromides. The p-phosphates thus obtained were coupled with GMP-morpholidate to yield the GDP derivatives 1-3. 

The 2-fluoro-arabinose derivative (15) has been prepared from the ribose N- gridinyl sulphonate (16) using potassium hydrogen difluoride. The fluoro-sugar phosphates (17) and (18) have been... 

Preparation 52), The ketopentose has been synthesized from D-arabinose by isomerization with pyridine followed by isolation as the crystalline o-nitrophenylhydrazone. The free sugar has not been crystallized. The D-erythro-pentu ose 5-phosphate may be obtained by treatment of D-glu-conic acid 6-phosphate with yeast enzymes (Chapter XIII). 

---