Cyclization of glucose

Eisenberg, F.J., 1967, d-myo inositol 1-phosphate as product of cyclization of glucose 6-phosphate and substrate for a specific phosphatase in rat testis. J. Biol. Chem. 242 1375-1382. 

Eisenberg, F., Bolden, A.H., and Loewus, F.A., 1964, Inositol formation by cyclization of glucose chain in rat testis. Biochem. Biophys. Res. Commun. 14 419-424. 

Chen, I.W., and Charalampous, F.C., 1967, Studies on the mechanism of cyclization of glucose 6-phosphate to D-inositol 1-phosphate. Biochim. Biophys. Acta. 136 568-570. 

Figure 28-10 The cyclization of glucose to form either the a- or the j3-cyclic form, (a) The linear representation of the aldehyde form of glucose, (b) A coiled representation that shows the aldehyde function group near the —OH group of carbon 5. (c) The two cyclic forms of glucose, (d) A stereoview of the a-form of glucose.

The biosynthesis of PI in mycobacteria appears to be similar to that of the eukaryotic cells. " The de novo synthesis of Ino typically involves cyclization of glucose-6-P04, a reaction catalyzed by Ino-1-phosphate synthase (INOl, Rv0046c). " Ino-1-phosphate is then dephosphorylated by an Ino monophosphate phospha-... 

Cyclization of glucose to give a- and p-D-glucose. Note that the carbonyl carbon (C-1) becomes chiral In this process, yielding the a- and p- forms of glucose. 

The cyclization of glucose. Two different rings are possible they differ in the orientation of the hydroxy group and hydrogen on one carbon, as indicated. The two forms are designated a and /3 and are shown here in two representations. 

To help depict the cyclization of glucose in Reaction 7.1, the open-chain structure has been bent around to position the functional groups in closer proximity. Notice the numbering of the carbon atoms that begins at the end of the chain, giving the lowest number to the carbonyl group carbon ... 

Fig. 7.9 Transition states for the cyclization of glucose- and mannose-derived radicals...

The labelings observed in the ring of phenylalanine are incompatible with the following mechanisms of formation of the benzene ring (1) condensation of three C2 units, (2) utilization of intermediates of the citric acid cycle, (3) condensation of two isotope-containing trioses, and (4) direct cyclization of glucose. 

FIGURE 21.4 Glucose in its cyclic pyranose forms. As explained in t)ie text, two anomers are formed by cyclization of glucose. Tlie molecule wliose newly formed -OH group at Ci is cis to tlie oxygen atom on the lowest chirality center (C5) in a Fischer projection is the a anomer. The molecule whose newly formed -OH group is trans to the oxygen atom on the lowest chirality center in a Fischer projection is the (3 anomer. 

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